Support tests in freestanding

Summary:
Freestanding is *weird*. The standard allows it to differ in a bunch of odd
manners from regular C++, and the committee would like to improve that
situation. I'd like to make libc++ behave better with what freestanding should
be, so that it can be a tool we use in improving the standard. To do that we
need to try stuff out, both with "freestanding the language mode" and
"freestanding the library subset".

Let's start with the super basic: run the libc++ tests in freestanding, using
clang as the compiler, and see what works. The easiest hack to do this:

In utils/libcxx/test/config.py add:

  self.cxx.compile_flags += ['-ffreestanding']

Run the tests and they all fail.

Why? Because in freestanding `main` isn't special. This "not special" property
has two effects: main doesn't get mangled, and main isn't allowed to omit its
`return` statement. The first means main gets mangled and the linker can't
create a valid executable for us to test. The second means we spew out warnings
(ew) and the compiler doesn't insert the `return` we omitted, and main just
falls of the end and does whatever undefined behavior (if you're luck, ud2
leading to non-zero return code).

Let's start my work with the basics. This patch changes all libc++ tests to
declare `main` as `int main(int, char**` so it mangles consistently (enabling us
to declare another `extern "C"` main for freestanding which calls the mangled
one), and adds `return 0;` to all places where it was missing. This touches 6124
files, and I apologize.

The former was done with The Magic Of Sed.

The later was done with a (not quite correct but decent) clang tool:

  https://gist.github.com/jfbastien/793819ff360baa845483dde81170feed

This works for most tests, though I did have to adjust a few places when e.g.
the test runs with `-x c`, macros are used for main (such as for the filesystem
tests), etc.

Once this is in we can create a freestanding bot which will prevent further
regressions. After that, we can start the real work of supporting C++
freestanding fairly well in libc++.

<rdar://problem/47754795>

Reviewers: ldionne, mclow.lists, EricWF

Subscribers: christof, jkorous, dexonsmith, arphaman, miyuki, libcxx-commits

Differential Revision: https://reviews.llvm.org/D57624

llvm-svn: 353086

308 files changed, 924 insertions, 308 deletions

diff --git a/libcxx/test/std/localization/c.locales/clocale.pass.cpp b/libcxx/test/std/localization/c.locales/clocale.pass.cpp
index 8217dd74da8..d8bd81b2ba3 100644
--- a/libcxx/test/std/localization/c.locales/clocale.pass.cpp
+++ b/libcxx/test/std/localization/c.locales/clocale.pass.cpp
@@ -43,7 +43,7 @@
 #error NULL not defined
 #endif
 
-int main()
+int main(int, char**)
 {
     std::lconv lc;
     ((void)lc); // Prevent unused warning
@@ -51,4 +51,6 @@ int main()
     static_assert((std::is_same<decltype(std::setlocale(0, "")), char*>::value), "");
 #endif
     static_assert((std::is_same<decltype(std::localeconv()), std::lconv*>::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.collate/locale.collate.byname/compare.pass.cpp b/libcxx/test/std/localization/locale.categories/category.collate/locale.collate.byname/compare.pass.cpp
index 33a94f9900d..1d76fa6094f 100644
--- a/libcxx/test/std/localization/locale.categories/category.collate/locale.collate.byname/compare.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.collate/locale.collate.byname/compare.pass.cpp
@@ -32,7 +32,7 @@
 
 #include "platform_support.h" // locale name macros
 
-int main()
+int main(int, char**)
 {
     {
         std::locale l(LOCALE_en_US_UTF_8);
@@ -68,4 +68,6 @@ int main()
                              s3.data(), s3.data() + s3.size()) == 1);
         }
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.collate/locale.collate.byname/hash.pass.cpp b/libcxx/test/std/localization/locale.categories/category.collate/locale.collate.byname/hash.pass.cpp
index 21cf03681ee..40c15d6e9f4 100644
--- a/libcxx/test/std/localization/locale.categories/category.collate/locale.collate.byname/hash.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.collate/locale.collate.byname/hash.pass.cpp
@@ -22,7 +22,7 @@
 
 #include "platform_support.h" // locale name macros
 
-int main()
+int main(int, char**)
 {
     std::locale l(LOCALE_en_US_UTF_8);
     {
@@ -39,4 +39,6 @@ int main()
         assert(f.hash(x1.data(), x1.data() + x1.size())
             != f.hash(x2.data(), x2.data() + x2.size()));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.collate/locale.collate.byname/transform.pass.cpp b/libcxx/test/std/localization/locale.categories/category.collate/locale.collate.byname/transform.pass.cpp
index 7cd3d0fe5e2..0b86979f55d 100644
--- a/libcxx/test/std/localization/locale.categories/category.collate/locale.collate.byname/transform.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.collate/locale.collate.byname/transform.pass.cpp
@@ -25,7 +25,7 @@
 
 #include "platform_support.h" // locale name macros
 
-int main()
+int main(int, char**)
 {
     {
         std::locale l(LOCALE_en_US_UTF_8);
@@ -53,4 +53,6 @@ int main()
             assert(f.transform(x.data(), x.data() + x.size()) == x);
         }
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.collate/locale.collate.byname/types.pass.cpp b/libcxx/test/std/localization/locale.categories/category.collate/locale.collate.byname/types.pass.cpp
index f00c8fd959d..f4dfd652227 100644
--- a/libcxx/test/std/localization/locale.categories/category.collate/locale.collate.byname/types.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.collate/locale.collate.byname/types.pass.cpp
@@ -30,7 +30,7 @@
 
 #include "platform_support.h" // locale name macros
 
-int main()
+int main(int, char**)
 {
     std::locale l(LOCALE_en_US_UTF_8);
     {
@@ -43,4 +43,6 @@ int main()
         assert(&std::use_facet<std::collate<wchar_t> >(l)
             == &std::use_facet<std::collate_byname<wchar_t> >(l));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.collate/locale.collate/ctor.pass.cpp b/libcxx/test/std/localization/locale.categories/category.collate/locale.collate/ctor.pass.cpp
index ded9ebae3ad..856074d391b 100644
--- a/libcxx/test/std/localization/locale.categories/category.collate/locale.collate/ctor.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.collate/locale.collate/ctor.pass.cpp
@@ -31,7 +31,7 @@ public:
 
 template <class C> int my_facet<C>::count = 0;
 
-int main()
+int main(int, char**)
 {
     {
         std::locale l(std::locale::classic(), new my_facet<char>);
@@ -63,4 +63,6 @@ int main()
         assert(my_facet<wchar_t>::count == 1);
     }
     assert(my_facet<wchar_t>::count == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.collate/locale.collate/locale.collate.members/compare.pass.cpp b/libcxx/test/std/localization/locale.categories/category.collate/locale.collate/locale.collate.members/compare.pass.cpp
index ff5aa4bddc4..bfbbebe3985 100644
--- a/libcxx/test/std/localization/locale.categories/category.collate/locale.collate/locale.collate.members/compare.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.collate/locale.collate/locale.collate.members/compare.pass.cpp
@@ -16,7 +16,7 @@
 #include <locale>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     {
@@ -45,4 +45,6 @@ int main()
         assert(f.compare(ib+1, ib+3, ia, ia+sa) == 1);
         assert(f.compare(ia, ia+3, ib, ib+3) == 0);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.collate/locale.collate/locale.collate.members/hash.pass.cpp b/libcxx/test/std/localization/locale.categories/category.collate/locale.collate/locale.collate.members/hash.pass.cpp
index 61d5a640f36..07e29b17f61 100644
--- a/libcxx/test/std/localization/locale.categories/category.collate/locale.collate/locale.collate.members/hash.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.collate/locale.collate/locale.collate.members/hash.pass.cpp
@@ -18,7 +18,7 @@
 #include <string>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     {
@@ -35,4 +35,6 @@ int main()
         assert(f.hash(x1.data(), x1.data() + x1.size())
             != f.hash(x2.data(), x2.data() + x2.size()));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.collate/locale.collate/locale.collate.members/transform.pass.cpp b/libcxx/test/std/localization/locale.categories/category.collate/locale.collate/locale.collate.members/transform.pass.cpp
index 7b8c9915f28..7588a82be41 100644
--- a/libcxx/test/std/localization/locale.categories/category.collate/locale.collate/locale.collate.members/transform.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.collate/locale.collate/locale.collate.members/transform.pass.cpp
@@ -16,7 +16,7 @@
 #include <string>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     {
@@ -29,4 +29,6 @@ int main()
         const std::collate<wchar_t>& f = std::use_facet<std::collate<wchar_t> >(l);
         assert(f.transform(x.data(), x.data() + x.size()) == x);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.collate/locale.collate/locale.collate.virtuals/tested_elsewhere.pass.cpp b/libcxx/test/std/localization/locale.categories/category.collate/locale.collate/locale.collate.virtuals/tested_elsewhere.pass.cpp
index f77636c8475..1f764da05d6 100644
--- a/libcxx/test/std/localization/locale.categories/category.collate/locale.collate/locale.collate.virtuals/tested_elsewhere.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.collate/locale.collate/locale.collate.virtuals/tested_elsewhere.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.collate/locale.collate/types.pass.cpp b/libcxx/test/std/localization/locale.categories/category.collate/locale.collate/types.pass.cpp
index 45957c3be28..63e2739f4e6 100644
--- a/libcxx/test/std/localization/locale.categories/category.collate/locale.collate/types.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.collate/locale.collate/types.pass.cpp
@@ -22,7 +22,7 @@
 #include <type_traits>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     {
@@ -47,4 +47,6 @@ int main()
         static_assert((std::is_same<std::collate<wchar_t>::string_type, std::wstring>::value), "");
         static_assert((std::is_base_of<std::locale::facet, std::collate<wchar_t> >::value), "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.collate/nothing_to_do.pass.cpp b/libcxx/test/std/localization/locale.categories/category.collate/nothing_to_do.pass.cpp
index f77636c8475..1f764da05d6 100644
--- a/libcxx/test/std/localization/locale.categories/category.collate/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.collate/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/ctype_base.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/ctype_base.pass.cpp
index 92024149c08..b7da91b4686 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/ctype_base.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/ctype_base.pass.cpp
@@ -38,7 +38,7 @@
 template <class T>
 void test(const T &) {}
 
-int main()
+int main(int, char**)
 {
     assert(std::ctype_base::space);
     assert(std::ctype_base::print);
@@ -74,4 +74,6 @@ int main()
     test(std::ctype_base::blank);
     test(std::ctype_base::alnum);
     test(std::ctype_base::graph);
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.dtor/dtor.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.dtor/dtor.pass.cpp
index 5ba7a67e40c..e38af450f7f 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.dtor/dtor.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.dtor/dtor.pass.cpp
@@ -17,7 +17,7 @@
 
 #include "count_new.hpp"
 
-int main()
+int main(int, char**)
 {
     {
         std::locale l(std::locale::classic(), new std::ctype<char>);
@@ -36,4 +36,6 @@ int main()
         assert(globalMemCounter.checkDeleteArrayCalledEq(0));
     }
     assert(globalMemCounter.checkDeleteArrayCalledEq(1));
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.members/ctor.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.members/ctor.pass.cpp
index 20eef3354c5..4ec37db021a 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.members/ctor.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.members/ctor.pass.cpp
@@ -29,7 +29,7 @@ public:
 
 int my_facet::count = 0;
 
-int main()
+int main(int, char**)
 {
     {
         std::locale l(std::locale::classic(), new my_facet);
@@ -46,4 +46,6 @@ int main()
         assert(my_facet::count == 1);
     }
     assert(my_facet::count == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.members/is_1.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.members/is_1.pass.cpp
index c4561f7964f..562f6c25e6b 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.members/is_1.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.members/is_1.pass.cpp
@@ -15,7 +15,7 @@
 #include <locale>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     {
@@ -55,4 +55,6 @@ int main()
         assert(f.is(F::graph, '.'));
         assert(!f.is(F::graph,  '\x07'));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.members/is_many.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.members/is_many.pass.cpp
index 9415d8b5a7d..c073a955e78 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.members/is_many.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.members/is_many.pass.cpp
@@ -19,7 +19,7 @@
 
 #include <stdio.h>
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     {
@@ -114,4 +114,6 @@ int main()
         assert( (m[5] & F::alnum));
         assert( (m[5] & F::graph));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.members/narrow_1.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.members/narrow_1.pass.cpp
index b0fa41a2f3d..d2fa02201a3 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.members/narrow_1.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.members/narrow_1.pass.cpp
@@ -15,7 +15,7 @@
 #include <locale>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     {
@@ -29,4 +29,6 @@ int main()
         assert(f.narrow('a', '*') == 'a');
         assert(f.narrow('1', '*') == '1');
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.members/narrow_many.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.members/narrow_many.pass.cpp
index 01bb8053456..48146954035 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.members/narrow_many.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.members/narrow_many.pass.cpp
@@ -17,7 +17,7 @@
 #include <vector>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     {
@@ -34,4 +34,6 @@ int main()
         assert(v[4] == 'a');
         assert(v[5] == '1');
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.members/scan_is.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.members/scan_is.pass.cpp
index 3f4f0490205..043ca679608 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.members/scan_is.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.members/scan_is.pass.cpp
@@ -19,7 +19,7 @@
 
 #include <stdio.h>
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     {
@@ -40,4 +40,6 @@ int main()
         assert(f.scan_is(F::alnum, in.data(), in.data() + in.size()) - in.data() == 1);
         assert(f.scan_is(F::graph, in.data(), in.data() + in.size()) - in.data() == 1);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.members/scan_not.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.members/scan_not.pass.cpp
index 6cd24a82e07..066a06a7f4c 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.members/scan_not.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.members/scan_not.pass.cpp
@@ -19,7 +19,7 @@
 
 #include <stdio.h>
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     {
@@ -40,4 +40,6 @@ int main()
         assert(f.scan_not(F::alnum, in.data(), in.data() + in.size()) - in.data() == 0);
         assert(f.scan_not(F::graph, in.data(), in.data() + in.size()) - in.data() == 0);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.members/table.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.members/table.pass.cpp
index 9d815196b18..6a0fea0b1fd 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.members/table.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.members/table.pass.cpp
@@ -15,7 +15,7 @@
 #include <locale>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     typedef std::ctype<char> F;
     {
@@ -29,4 +29,6 @@ int main()
         const F& f = std::use_facet<F>(l);
         assert(f.table() == table);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.members/tolower_1.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.members/tolower_1.pass.cpp
index 2b817002ce7..ddf4fbdb057 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.members/tolower_1.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.members/tolower_1.pass.cpp
@@ -15,7 +15,7 @@
 #include <locale>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     {
@@ -29,4 +29,6 @@ int main()
         assert(f.tolower('a') == 'a');
         assert(f.tolower('1') == '1');
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.members/tolower_many.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.members/tolower_many.pass.cpp
index 036ed25c6a3..b307d462735 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.members/tolower_many.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.members/tolower_many.pass.cpp
@@ -16,7 +16,7 @@
 #include <string>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     {
@@ -32,4 +32,6 @@ int main()
         assert(in[4] == 'a');
         assert(in[5] == '1');
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.members/toupper_1.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.members/toupper_1.pass.cpp
index c393bb91b8e..8b5505910ee 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.members/toupper_1.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.members/toupper_1.pass.cpp
@@ -15,7 +15,7 @@
 #include <locale>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     {
@@ -29,4 +29,6 @@ int main()
         assert(f.toupper('a') == 'A');
         assert(f.toupper('1') == '1');
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.members/toupper_many.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.members/toupper_many.pass.cpp
index 25af985f7c8..3d1c453cf39 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.members/toupper_many.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.members/toupper_many.pass.cpp
@@ -16,7 +16,7 @@
 #include <string>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     {
@@ -32,4 +32,6 @@ int main()
         assert(in[4] == 'A');
         assert(in[5] == '1');
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.members/widen_1.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.members/widen_1.pass.cpp
index 5b9f74bad91..81c3ab6b3c4 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.members/widen_1.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.members/widen_1.pass.cpp
@@ -15,7 +15,7 @@
 #include <locale>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     {
@@ -29,4 +29,6 @@ int main()
         assert(f.widen('a') == 'a');
         assert(f.widen('1') == '1');
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.members/widen_many.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.members/widen_many.pass.cpp
index ab3a838c087..35d9335c252 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.members/widen_many.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.members/widen_many.pass.cpp
@@ -17,7 +17,7 @@
 #include <vector>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     {
@@ -34,4 +34,6 @@ int main()
         assert(v[4] == 'a');
         assert(v[5] == '1');
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.statics/classic_table.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.statics/classic_table.pass.cpp
index 1aef57d3fb7..7f46238d682 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.statics/classic_table.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.statics/classic_table.pass.cpp
@@ -15,7 +15,7 @@
 #include <locale>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     typedef std::ctype<char> F;
     assert(F::classic_table() != 0);
@@ -55,4 +55,6 @@ int main()
         assert(((p[i] & ~set) & defined) == 0);   // no extra ones
     }
 
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.virtuals/tested_elsewhere.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.virtuals/tested_elsewhere.pass.cpp
index f77636c8475..1f764da05d6 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.virtuals/tested_elsewhere.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/facet.ctype.char.virtuals/tested_elsewhere.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/types.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/types.pass.cpp
index b23f9ef83d8..c46dbb3e6f1 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/types.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/facet.ctype.special/types.pass.cpp
@@ -21,7 +21,7 @@
 #include <type_traits>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     {
@@ -35,4 +35,6 @@ int main()
         static_assert((std::is_base_of<std::ctype_base, std::ctype<char> >::value), "");
         static_assert((std::is_base_of<std::locale::facet, std::ctype<char> >::value), "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt.byname/ctor_char.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt.byname/ctor_char.pass.cpp
index d5cde475453..03d17375e5e 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt.byname/ctor_char.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt.byname/ctor_char.pass.cpp
@@ -36,7 +36,7 @@ public:
 
 int my_facet::count = 0;
 
-int main()
+int main(int, char**)
 {
     {
         std::locale l(std::locale::classic(), new my_facet(LOCALE_en_US));
@@ -68,4 +68,6 @@ int main()
         assert(my_facet::count == 1);
     }
     assert(my_facet::count == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt.byname/ctor_char16_t.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt.byname/ctor_char16_t.pass.cpp
index 4d2803815de..eedf192db26 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt.byname/ctor_char16_t.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt.byname/ctor_char16_t.pass.cpp
@@ -34,7 +34,7 @@ public:
 
 int my_facet::count = 0;
 
-int main()
+int main(int, char**)
 {
     {
         std::locale l(std::locale::classic(), new my_facet("en_US"));
@@ -66,4 +66,6 @@ int main()
         assert(my_facet::count == 1);
     }
     assert(my_facet::count == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt.byname/ctor_char32_t.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt.byname/ctor_char32_t.pass.cpp
index 50bf5834902..8e5d70356ab 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt.byname/ctor_char32_t.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt.byname/ctor_char32_t.pass.cpp
@@ -34,7 +34,7 @@ public:
 
 int my_facet::count = 0;
 
-int main()
+int main(int, char**)
 {
     {
         std::locale l(std::locale::classic(), new my_facet("en_US"));
@@ -66,4 +66,6 @@ int main()
         assert(my_facet::count == 1);
     }
     assert(my_facet::count == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt.byname/ctor_wchar_t.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt.byname/ctor_wchar_t.pass.cpp
index 2379b163151..5503192ca98 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt.byname/ctor_wchar_t.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt.byname/ctor_wchar_t.pass.cpp
@@ -38,7 +38,7 @@ public:
 
 int my_facet::count = 0;
 
-int main()
+int main(int, char**)
 {
     {
         std::locale l(std::locale::classic(), new my_facet(LOCALE_en_US_UTF_8));
@@ -70,4 +70,6 @@ int main()
         assert(my_facet::count == 1);
     }
     assert(my_facet::count == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/codecvt_base.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/codecvt_base.pass.cpp
index f6b94c5f185..c2e40542e0e 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/codecvt_base.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/codecvt_base.pass.cpp
@@ -17,10 +17,12 @@
 #include <locale>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     assert(std::codecvt_base::ok == 0);
     assert(std::codecvt_base::partial == 1);
     assert(std::codecvt_base::error == 2);
     assert(std::codecvt_base::noconv == 3);
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/ctor_char.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/ctor_char.pass.cpp
index e12d301686c..3f0dc9e7cc1 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/ctor_char.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/ctor_char.pass.cpp
@@ -31,7 +31,7 @@ public:
 
 int my_facet::count = 0;
 
-int main()
+int main(int, char**)
 {
     {
         std::locale l(std::locale::classic(), new my_facet);
@@ -48,4 +48,6 @@ int main()
         assert(my_facet::count == 1);
     }
     assert(my_facet::count == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/ctor_char16_t.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/ctor_char16_t.pass.cpp
index e0ed00dfd61..e2df342d4e6 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/ctor_char16_t.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/ctor_char16_t.pass.cpp
@@ -35,7 +35,7 @@ int my_facet::count = 0;
 
 //#endif
 
-int main()
+int main(int, char**)
 {
 //#ifndef _LIBCPP_HAS_NO_UNICODE_CHARS
     {
@@ -54,4 +54,6 @@ int main()
     }
     assert(my_facet::count == 0);
 //#endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/ctor_char32_t.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/ctor_char32_t.pass.cpp
index 56d63764df6..0df7f3515df 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/ctor_char32_t.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/ctor_char32_t.pass.cpp
@@ -35,7 +35,7 @@ int my_facet::count = 0;
 
 //#endif
 
-int main()
+int main(int, char**)
 {
 //#ifndef _LIBCPP_HAS_NO_UNICODE_CHARS
     {
@@ -54,4 +54,6 @@ int main()
     }
     assert(my_facet::count == 0);
 //#endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/ctor_wchar_t.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/ctor_wchar_t.pass.cpp
index 8f4293ee83b..6917e1b7220 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/ctor_wchar_t.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/ctor_wchar_t.pass.cpp
@@ -31,7 +31,7 @@ public:
 
 int my_facet::count = 0;
 
-int main()
+int main(int, char**)
 {
     {
         std::locale l(std::locale::classic(), new my_facet);
@@ -48,4 +48,6 @@ int main()
         assert(my_facet::count == 1);
     }
     assert(my_facet::count == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char16_t_always_noconv.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char16_t_always_noconv.pass.cpp
index 2f84eb6c92b..e1741aec05e 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char16_t_always_noconv.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char16_t_always_noconv.pass.cpp
@@ -17,9 +17,11 @@
 
 typedef std::codecvt<char16_t, char, std::mbstate_t> F;
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     const F& f = std::use_facet<F>(l);
     assert(!f.always_noconv());
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char16_t_encoding.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char16_t_encoding.pass.cpp
index 4a30c4ee8f9..f4614984ad7 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char16_t_encoding.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char16_t_encoding.pass.cpp
@@ -17,9 +17,11 @@
 
 typedef std::codecvt<char16_t, char, std::mbstate_t> F;
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     const F& f = std::use_facet<F>(l);
     assert(f.encoding() == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char16_t_in.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char16_t_in.pass.cpp
index 6a883d3d44f..2a6a07ef957 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char16_t_in.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char16_t_in.pass.cpp
@@ -21,7 +21,7 @@
 
 typedef std::codecvt<char16_t, char, std::mbstate_t> F;
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     const char from[] = "some text";
@@ -36,4 +36,6 @@ int main()
     assert(to_next - to == 9);
     for (unsigned i = 0; i < 9; ++i)
         assert(to[i] == from[i]);
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char16_t_length.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char16_t_length.pass.cpp
index a48b902e1dd..038ae971136 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char16_t_length.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char16_t_length.pass.cpp
@@ -17,7 +17,7 @@
 
 typedef std::codecvt<char16_t, char, std::mbstate_t> F;
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     const F& f = std::use_facet<F>(l);
@@ -28,4 +28,6 @@ int main()
     assert(f.length(mbs, from, from+10, 9) == 9);
     assert(f.length(mbs, from, from+10, 10) == 10);
     assert(f.length(mbs, from, from+10, 100) == 10);
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char16_t_max_length.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char16_t_max_length.pass.cpp
index 69c711f60a3..bcaa7052876 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char16_t_max_length.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char16_t_max_length.pass.cpp
@@ -17,9 +17,11 @@
 
 typedef std::codecvt<char16_t, char, std::mbstate_t> F;
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     const F& f = std::use_facet<F>(l);
     assert(f.max_length() == 4);
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char16_t_out.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char16_t_out.pass.cpp
index 9b5d0f988ab..cff42b0c054 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char16_t_out.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char16_t_out.pass.cpp
@@ -23,7 +23,7 @@
 
 typedef std::codecvt<char16_t, char, std::mbstate_t> F;
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     const F& f = std::use_facet<F>(l);
@@ -41,4 +41,6 @@ int main()
         for (unsigned i = 0; i < 9; ++i)
             assert(to[i] == from[i]);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char16_t_unshift.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char16_t_unshift.pass.cpp
index bde44c0889a..5b027bae7b5 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char16_t_unshift.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char16_t_unshift.pass.cpp
@@ -20,7 +20,7 @@
 
 typedef std::codecvt<char16_t, char, std::mbstate_t> F;
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     std::vector<char> to(3);
@@ -29,4 +29,6 @@ int main()
     char* to_next = 0;
     assert(f.unshift(mbs, to.data(), to.data() + to.size(), to_next) == F::noconv);
     assert(to_next == to.data());
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char32_t_always_noconv.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char32_t_always_noconv.pass.cpp
index 2ef1e5c657d..2b2f136e3b4 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char32_t_always_noconv.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char32_t_always_noconv.pass.cpp
@@ -17,9 +17,11 @@
 
 typedef std::codecvt<char32_t, char, std::mbstate_t> F;
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     const F& f = std::use_facet<F>(l);
     assert(!f.always_noconv());
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char32_t_encoding.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char32_t_encoding.pass.cpp
index 834bd607689..0d2f35fc2c2 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char32_t_encoding.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char32_t_encoding.pass.cpp
@@ -17,9 +17,11 @@
 
 typedef std::codecvt<char32_t, char, std::mbstate_t> F;
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     const F& f = std::use_facet<F>(l);
     assert(f.encoding() == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char32_t_in.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char32_t_in.pass.cpp
index 8472a569226..eb7c53fcea6 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char32_t_in.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char32_t_in.pass.cpp
@@ -21,7 +21,7 @@
 
 typedef std::codecvt<char32_t, char, std::mbstate_t> F;
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     const char from[] = "some text";
@@ -36,4 +36,6 @@ int main()
     assert(to_next - to == 9);
     for (unsigned i = 0; i < 9; ++i)
         assert(to[i] == static_cast<char32_t>(from[i]));
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char32_t_length.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char32_t_length.pass.cpp
index 6986314e3f4..da853068883 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char32_t_length.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char32_t_length.pass.cpp
@@ -17,7 +17,7 @@
 
 typedef std::codecvt<char32_t, char, std::mbstate_t> F;
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     const F& f = std::use_facet<F>(l);
@@ -28,4 +28,6 @@ int main()
     assert(f.length(mbs, from, from+10, 9) == 9);
     assert(f.length(mbs, from, from+10, 10) == 10);
     assert(f.length(mbs, from, from+10, 100) == 10);
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char32_t_max_length.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char32_t_max_length.pass.cpp
index 921ec18549c..f31dba747c7 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char32_t_max_length.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char32_t_max_length.pass.cpp
@@ -17,9 +17,11 @@
 
 typedef std::codecvt<char32_t, char, std::mbstate_t> F;
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     const F& f = std::use_facet<F>(l);
     assert(f.max_length() == 4);
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char32_t_out.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char32_t_out.pass.cpp
index 210f8c052e5..7ed5609436c 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char32_t_out.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char32_t_out.pass.cpp
@@ -23,7 +23,7 @@
 
 typedef std::codecvt<char32_t, char, std::mbstate_t> F;
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     const F& f = std::use_facet<F>(l);
@@ -41,4 +41,6 @@ int main()
         for (unsigned i = 0; i < 9; ++i)
             assert(static_cast<char32_t>(to[i]) == from[i]);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char32_t_unshift.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char32_t_unshift.pass.cpp
index 26981d3c85c..aaf9a6a20e6 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char32_t_unshift.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char32_t_unshift.pass.cpp
@@ -20,7 +20,7 @@
 
 typedef std::codecvt<char32_t, char, std::mbstate_t> F;
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     std::vector<char> to(3);
@@ -29,4 +29,6 @@ int main()
     char* to_next = 0;
     assert(f.unshift(mbs, to.data(), to.data() + to.size(), to_next) == F::noconv);
     assert(to_next == to.data());
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char_always_noconv.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char_always_noconv.pass.cpp
index 2590c2b0e62..c253bbed72f 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char_always_noconv.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char_always_noconv.pass.cpp
@@ -17,9 +17,11 @@
 
 typedef std::codecvt<char, char, std::mbstate_t> F;
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     const F& f = std::use_facet<F>(l);
     assert(f.always_noconv());
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char_encoding.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char_encoding.pass.cpp
index 571ab84d888..79c26add6ab 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char_encoding.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char_encoding.pass.cpp
@@ -17,9 +17,11 @@
 
 typedef std::codecvt<char, char, std::mbstate_t> F;
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     const F& f = std::use_facet<F>(l);
     assert(f.encoding() == 1);
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char_in.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char_in.pass.cpp
index 2b7c610e461..1f2cdb6be45 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char_in.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char_in.pass.cpp
@@ -21,7 +21,7 @@
 
 typedef std::codecvt<char, char, std::mbstate_t> F;
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     const std::basic_string<F::intern_type> from("some text");
@@ -34,4 +34,6 @@ int main()
                      to.data(), to.data() + to.size(), to_next) == F::noconv);
     assert(from_next == from.data());
     assert(to_next == to.data());
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char_length.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char_length.pass.cpp
index b930009b516..ad45cba5f43 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char_length.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char_length.pass.cpp
@@ -17,7 +17,7 @@
 
 typedef std::codecvt<char, char, std::mbstate_t> F;
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     const F& f = std::use_facet<F>(l);
@@ -28,4 +28,6 @@ int main()
     assert(f.length(mbs, from, from+10, 10) == 10);
     assert(f.length(mbs, from, from+10, 11) == 10);
     assert(f.length(mbs, from, from+10, 100) == 10);
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char_max_length.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char_max_length.pass.cpp
index adc0b1707b1..437e72b94ca 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char_max_length.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char_max_length.pass.cpp
@@ -17,9 +17,11 @@
 
 typedef std::codecvt<char, char, std::mbstate_t> F;
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     const F& f = std::use_facet<F>(l);
     assert(f.max_length() == 1);
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char_out.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char_out.pass.cpp
index 28b4be7455b..be266746cda 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char_out.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char_out.pass.cpp
@@ -21,7 +21,7 @@
 
 typedef std::codecvt<char, char, std::mbstate_t> F;
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     const std::basic_string<F::intern_type> from("some text");
@@ -34,4 +34,6 @@ int main()
                       to.data(), to.data() + to.size(), to_next) == F::noconv);
     assert(from_next == from.data());
     assert(to_next == to.data());
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char_unshift.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char_unshift.pass.cpp
index 56c10aa52e4..a3d9e3d14bd 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char_unshift.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/char_unshift.pass.cpp
@@ -20,7 +20,7 @@
 
 typedef std::codecvt<char, char, std::mbstate_t> F;
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     std::vector<char> to(3);
@@ -29,4 +29,6 @@ int main()
     char* to_next = 0;
     assert(f.unshift(mbs, to.data(), to.data() + to.size(), to_next) == F::noconv);
     assert(to_next == to.data());
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/utf_sanity_check.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/utf_sanity_check.pass.cpp
index 2d338dd8ee0..eaae7b6e97b 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/utf_sanity_check.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/utf_sanity_check.pass.cpp
@@ -20,7 +20,7 @@
 
 #include <stdio.h>
 
-int main()
+int main(int, char**)
 {
     typedef std::codecvt<char32_t, char, std::mbstate_t> F32_8;
     typedef std::codecvt<char16_t, char, std::mbstate_t> F16_8;
@@ -123,4 +123,6 @@ int main()
             assert(c32 == c32x);
         }
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/wchar_t_always_noconv.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/wchar_t_always_noconv.pass.cpp
index df645174767..484b2213d24 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/wchar_t_always_noconv.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/wchar_t_always_noconv.pass.cpp
@@ -17,9 +17,11 @@
 
 typedef std::codecvt<wchar_t, char, std::mbstate_t> F;
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     const F& f = std::use_facet<F>(l);
     assert(!f.always_noconv());
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/wchar_t_encoding.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/wchar_t_encoding.pass.cpp
index ed33018b274..9c075af1372 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/wchar_t_encoding.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/wchar_t_encoding.pass.cpp
@@ -17,9 +17,11 @@
 
 typedef std::codecvt<wchar_t, char, std::mbstate_t> F;
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     const F& f = std::use_facet<F>(l);
     assert(f.encoding() == 1);
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/wchar_t_in.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/wchar_t_in.pass.cpp
index 7ca632e4e5e..bec0e6cb0ac 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/wchar_t_in.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/wchar_t_in.pass.cpp
@@ -22,7 +22,7 @@
 
 typedef std::codecvt<wchar_t, char, std::mbstate_t> F;
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     const std::basic_string<F::extern_type> from("some text");
@@ -39,4 +39,6 @@ int main()
     assert(static_cast<std::size_t>(to_next - to.data()) == expected.size());
     assert(static_cast<std::size_t>(to_next - to.data()) == expected.size());
     assert(to == expected);
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/wchar_t_length.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/wchar_t_length.pass.cpp
index 0fcab1af7ae..4fd5d329386 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/wchar_t_length.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/wchar_t_length.pass.cpp
@@ -17,7 +17,7 @@
 
 typedef std::codecvt<wchar_t, char, std::mbstate_t> F;
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     const F& f = std::use_facet<F>(l);
@@ -28,4 +28,6 @@ int main()
     assert(f.length(mbs, from, from+10, 10) == 10);
     assert(f.length(mbs, from, from+10, 11) == 10);
     assert(f.length(mbs, from, from+10, 100) == 10);
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/wchar_t_max_length.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/wchar_t_max_length.pass.cpp
index fefd11016fe..90d91315197 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/wchar_t_max_length.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/wchar_t_max_length.pass.cpp
@@ -17,9 +17,11 @@
 
 typedef std::codecvt<wchar_t, char, std::mbstate_t> F;
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     const F& f = std::use_facet<F>(l);
     assert(f.max_length() == 1);
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/wchar_t_out.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/wchar_t_out.pass.cpp
index 8769b881469..bc12bdbce64 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/wchar_t_out.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/wchar_t_out.pass.cpp
@@ -23,7 +23,7 @@
 
 typedef std::codecvt<wchar_t, char, std::mbstate_t> F;
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     const F& f = std::use_facet<F>(l);
@@ -67,4 +67,6 @@ int main()
         assert(static_cast<std::size_t>(to_next - to.data()) == to.size()-1);
         assert(to.data() == std::string("some te"));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/wchar_t_unshift.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/wchar_t_unshift.pass.cpp
index 9241c7a4702..e0f7c3c9520 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/wchar_t_unshift.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.members/wchar_t_unshift.pass.cpp
@@ -22,7 +22,7 @@
 
 typedef std::codecvt<wchar_t, char, std::mbstate_t> F;
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     std::vector<F::extern_type> to(3);
@@ -31,4 +31,6 @@ int main()
     F::extern_type* to_next = 0;
     assert(f.unshift(mbs, to.data(), to.data() + to.size(), to_next) == F::ok);
     assert(to_next == to.data());
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.virtuals/tested_elsewhere.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.virtuals/tested_elsewhere.pass.cpp
index f77636c8475..1f764da05d6 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.virtuals/tested_elsewhere.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/locale.codecvt.virtuals/tested_elsewhere.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/types_char.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/types_char.pass.cpp
index 12fee2682da..455cf03ee71 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/types_char.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/types_char.pass.cpp
@@ -24,7 +24,7 @@
 #include <type_traits>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     typedef std::codecvt<char, char, std::mbstate_t> F;
     static_assert((std::is_base_of<std::locale::facet, F>::value), "");
@@ -37,4 +37,6 @@ int main()
     const F& f = std::use_facet<F>(l);
     ((void)f); // Prevent unused warning
     (void)F::id;
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/types_char16_t.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/types_char16_t.pass.cpp
index b01bd5a7abd..f52c60f1bfd 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/types_char16_t.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/types_char16_t.pass.cpp
@@ -24,7 +24,7 @@
 #include <type_traits>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     typedef std::codecvt<char16_t, char, std::mbstate_t> F;
     static_assert((std::is_base_of<std::locale::facet, F>::value), "");
@@ -37,4 +37,6 @@ int main()
     const F& f = std::use_facet<F>(l);
     (void)F::id;
     ((void)f);
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/types_char32_t.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/types_char32_t.pass.cpp
index 6ad4697542d..c75de419c86 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/types_char32_t.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/types_char32_t.pass.cpp
@@ -24,7 +24,7 @@
 #include <type_traits>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     typedef std::codecvt<char32_t, char, std::mbstate_t> F;
     static_assert((std::is_base_of<std::locale::facet, F>::value), "");
@@ -37,4 +37,6 @@ int main()
     const F& f = std::use_facet<F>(l);
     (void)F::id;
     ((void)f);
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/types_wchar_t.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/types_wchar_t.pass.cpp
index 6c19e41a8e4..07e25be718c 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/types_wchar_t.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.codecvt/types_wchar_t.pass.cpp
@@ -24,7 +24,7 @@
 #include <type_traits>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     typedef std::codecvt<wchar_t, char, std::mbstate_t> F;
     static_assert((std::is_base_of<std::locale::facet, F>::value), "");
@@ -37,4 +37,6 @@ int main()
     const F& f = std::use_facet<F>(l);
     ((void)f); // Prevent unused warning
     (void)F::id;
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype.byname/is_1.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype.byname/is_1.pass.cpp
index 32acd85d18b..3331c5a67d8 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype.byname/is_1.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype.byname/is_1.pass.cpp
@@ -20,7 +20,7 @@
 
 #include "platform_support.h" // locale name macros
 
-int main()
+int main(int, char**)
 {
     {
         std::locale l(LOCALE_en_US_UTF_8);
@@ -108,4 +108,6 @@ int main()
             assert(!f.is(F::upper, L'\x00DA'));
         }
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype.byname/is_many.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype.byname/is_many.pass.cpp
index 1087b88c0c2..6751fd60de0 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype.byname/is_many.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype.byname/is_many.pass.cpp
@@ -23,7 +23,7 @@
 
 #include "platform_support.h" // locale name macros
 
-int main()
+int main(int, char**)
 {
     {
         std::locale l(LOCALE_en_US_UTF_8);
@@ -243,4 +243,6 @@ int main()
             assert( (m[6] & F::graph));
         }
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype.byname/mask.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype.byname/mask.pass.cpp
index 45d90ddd540..3a6360eb9de 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype.byname/mask.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype.byname/mask.pass.cpp
@@ -16,7 +16,7 @@
 #include <type_traits>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         std::locale l("C");
@@ -49,4 +49,6 @@ int main()
             assert( cf.is(CF::alpha,  'a'));
         }
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype.byname/narrow_1.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype.byname/narrow_1.pass.cpp
index 19d751d2995..6d193772501 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype.byname/narrow_1.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype.byname/narrow_1.pass.cpp
@@ -20,7 +20,7 @@
 
 #include "platform_support.h" // locale name macros
 
-int main()
+int main(int, char**)
 {
     {
         std::locale l(std::string(LOCALE_fr_CA_ISO8859_1));
@@ -52,4 +52,6 @@ int main()
             assert(f.narrow(L'\xDA', '*') == '*');
         }
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype.byname/narrow_many.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype.byname/narrow_many.pass.cpp
index c51b97311a1..7ab4874fbcd 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype.byname/narrow_many.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype.byname/narrow_many.pass.cpp
@@ -22,7 +22,7 @@
 
 #include "platform_support.h" // locale name macros
 
-int main()
+int main(int, char**)
 {
     {
         std::locale l(LOCALE_fr_CA_ISO8859_1);
@@ -60,4 +60,6 @@ int main()
             assert(v[6] == '*');
         }
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype.byname/scan_is.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype.byname/scan_is.pass.cpp
index 6c875863fb5..b736dd7862c 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype.byname/scan_is.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype.byname/scan_is.pass.cpp
@@ -23,7 +23,7 @@
 
 #include "platform_support.h" // locale name macros
 
-int main()
+int main(int, char**)
 {
     {
         std::locale l(LOCALE_en_US_UTF_8);
@@ -67,4 +67,6 @@ int main()
             assert(f.scan_is(F::graph, in.data(), in.data() + in.size()) - in.data() == 2);
         }
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype.byname/scan_not.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype.byname/scan_not.pass.cpp
index dbeeae4c699..fa7674a8ca0 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype.byname/scan_not.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype.byname/scan_not.pass.cpp
@@ -23,7 +23,7 @@
 
 #include "platform_support.h" // locale name macros
 
-int main()
+int main(int, char**)
 {
     {
         std::locale l(LOCALE_en_US_UTF_8);
@@ -67,4 +67,6 @@ int main()
             assert(f.scan_not(F::graph, in.data(), in.data() + in.size()) - in.data() == 0);
         }
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype.byname/tolower_1.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype.byname/tolower_1.pass.cpp
index 3f9ab9dce27..ab5daa7aa38 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype.byname/tolower_1.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype.byname/tolower_1.pass.cpp
@@ -19,7 +19,7 @@
 
 #include "platform_support.h" // locale name macros
 
-int main()
+int main(int, char**)
 {
     {
         std::locale l;
@@ -88,4 +88,6 @@ int main()
             assert(f.tolower(L'\xFA') == L'\xFA');
         }
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype.byname/tolower_many.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype.byname/tolower_many.pass.cpp
index 29021e0f4ce..29403cb1010 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype.byname/tolower_many.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype.byname/tolower_many.pass.cpp
@@ -20,7 +20,7 @@
 
 #include "platform_support.h" // locale name macros
 
-int main()
+int main(int, char**)
 {
     {
         std::locale l;
@@ -94,4 +94,6 @@ int main()
             assert(in[6] == L'1');
         }
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype.byname/toupper_1.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype.byname/toupper_1.pass.cpp
index b9c882c9a74..56304a7558a 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype.byname/toupper_1.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype.byname/toupper_1.pass.cpp
@@ -20,7 +20,7 @@
 
 #include "platform_support.h" // locale name macros
 
-int main()
+int main(int, char**)
 {
     {
         std::locale l;
@@ -90,4 +90,6 @@ int main()
             assert(f.toupper(L'\xFA') == L'\xFA');
         }
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype.byname/toupper_many.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype.byname/toupper_many.pass.cpp
index 2b0669cb30e..bfc3bf848ad 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype.byname/toupper_many.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype.byname/toupper_many.pass.cpp
@@ -20,7 +20,7 @@
 
 #include "platform_support.h" // locale name macros
 
-int main()
+int main(int, char**)
 {
     {
         std::locale l;
@@ -94,4 +94,6 @@ int main()
             assert(in[6] == L'1');
         }
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype.byname/types.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype.byname/types.pass.cpp
index 9ec94681611..ce0a0e30ed6 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype.byname/types.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype.byname/types.pass.cpp
@@ -28,7 +28,7 @@
 
 #include "platform_support.h" // locale name macros
 
-int main()
+int main(int, char**)
 {
     {
         std::locale l(LOCALE_en_US_UTF_8);
@@ -56,4 +56,6 @@ int main()
                 == &std::use_facet<std::ctype_byname<wchar_t> >(l));
         }
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype.byname/widen_1.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype.byname/widen_1.pass.cpp
index 5752bb82bb8..1dc9b7de805 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype.byname/widen_1.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype.byname/widen_1.pass.cpp
@@ -23,7 +23,7 @@
 
 #include "platform_support.h" // locale name macros
 
-int main()
+int main(int, char**)
 {
     {
         std::locale l;
@@ -61,4 +61,6 @@ int main()
 #endif
         }
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype.byname/widen_many.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype.byname/widen_many.pass.cpp
index 4f5efca1d66..67a97ba6826 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype.byname/widen_many.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype.byname/widen_many.pass.cpp
@@ -23,7 +23,7 @@
 
 #include "platform_support.h" // locale name macros
 
-int main()
+int main(int, char**)
 {
     {
         std::locale l(LOCALE_en_US_UTF_8);
@@ -67,4 +67,6 @@ int main()
 #endif
         }
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/ctor.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/ctor.pass.cpp
index e41b93b78a2..f53d4e9645d 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/ctor.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/ctor.pass.cpp
@@ -30,7 +30,7 @@ public:
 
 template <class C> int my_facet<C>::count = 0;
 
-int main()
+int main(int, char**)
 {
     {
         std::locale l(std::locale::classic(), new my_facet<wchar_t>);
@@ -47,4 +47,6 @@ int main()
         assert(my_facet<wchar_t>::count == 1);
     }
     assert(my_facet<wchar_t>::count == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/locale.ctype.members/is_1.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/locale.ctype.members/is_1.pass.cpp
index a48f75f4f7d..23a1aa9d21a 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/locale.ctype.members/is_1.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/locale.ctype.members/is_1.pass.cpp
@@ -15,7 +15,7 @@
 #include <locale>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     {
@@ -55,4 +55,6 @@ int main()
         assert(f.is(F::graph, L'.'));
         assert(!f.is(F::graph,  L'\x07'));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/locale.ctype.members/is_many.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/locale.ctype.members/is_many.pass.cpp
index f348d208077..d9dd5b58ab4 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/locale.ctype.members/is_many.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/locale.ctype.members/is_many.pass.cpp
@@ -19,7 +19,7 @@
 
 #include <stdio.h>
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     {
@@ -114,4 +114,6 @@ int main()
         assert( (m[5] & F::alnum));
         assert( (m[5] & F::graph));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/locale.ctype.members/narrow_1.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/locale.ctype.members/narrow_1.pass.cpp
index 1e1194bdad8..55e1f378b43 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/locale.ctype.members/narrow_1.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/locale.ctype.members/narrow_1.pass.cpp
@@ -15,7 +15,7 @@
 #include <locale>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     {
@@ -29,4 +29,6 @@ int main()
         assert(f.narrow(L'a', '*') == 'a');
         assert(f.narrow(L'1', '*') == '1');
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/locale.ctype.members/narrow_many.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/locale.ctype.members/narrow_many.pass.cpp
index 523fb250342..47c2b51887e 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/locale.ctype.members/narrow_many.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/locale.ctype.members/narrow_many.pass.cpp
@@ -17,7 +17,7 @@
 #include <vector>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     {
@@ -34,4 +34,6 @@ int main()
         assert(v[4] == 'a');
         assert(v[5] == '1');
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/locale.ctype.members/scan_is.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/locale.ctype.members/scan_is.pass.cpp
index 23718fec18a..1891b155b31 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/locale.ctype.members/scan_is.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/locale.ctype.members/scan_is.pass.cpp
@@ -19,7 +19,7 @@
 
 #include <stdio.h>
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     {
@@ -40,4 +40,6 @@ int main()
         assert(f.scan_is(F::alnum, in.data(), in.data() + in.size()) - in.data() == 1);
         assert(f.scan_is(F::graph, in.data(), in.data() + in.size()) - in.data() == 1);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/locale.ctype.members/scan_not.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/locale.ctype.members/scan_not.pass.cpp
index 22bc1470199..40cc8c0fa0d 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/locale.ctype.members/scan_not.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/locale.ctype.members/scan_not.pass.cpp
@@ -19,7 +19,7 @@
 
 #include <stdio.h>
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     {
@@ -40,4 +40,6 @@ int main()
         assert(f.scan_not(F::alnum, in.data(), in.data() + in.size()) - in.data() == 0);
         assert(f.scan_not(F::graph, in.data(), in.data() + in.size()) - in.data() == 0);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/locale.ctype.members/tolower_1.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/locale.ctype.members/tolower_1.pass.cpp
index b5c402de212..1ae14410c6f 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/locale.ctype.members/tolower_1.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/locale.ctype.members/tolower_1.pass.cpp
@@ -15,7 +15,7 @@
 #include <locale>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     {
@@ -29,4 +29,6 @@ int main()
         assert(f.tolower(L'a') == L'a');
         assert(f.tolower(L'1') == L'1');
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/locale.ctype.members/tolower_many.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/locale.ctype.members/tolower_many.pass.cpp
index 92bbc8ceb43..711343d3c5a 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/locale.ctype.members/tolower_many.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/locale.ctype.members/tolower_many.pass.cpp
@@ -16,7 +16,7 @@
 #include <string>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     {
@@ -32,4 +32,6 @@ int main()
         assert(in[4] == L'a');
         assert(in[5] == L'1');
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/locale.ctype.members/toupper_1.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/locale.ctype.members/toupper_1.pass.cpp
index 0ed6e4504fb..fbc28a1b87c 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/locale.ctype.members/toupper_1.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/locale.ctype.members/toupper_1.pass.cpp
@@ -15,7 +15,7 @@
 #include <locale>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     {
@@ -29,4 +29,6 @@ int main()
         assert(f.toupper(L'a') == L'A');
         assert(f.toupper(L'1') == L'1');
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/locale.ctype.members/toupper_many.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/locale.ctype.members/toupper_many.pass.cpp
index 0510778eb3b..963e894a7e1 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/locale.ctype.members/toupper_many.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/locale.ctype.members/toupper_many.pass.cpp
@@ -16,7 +16,7 @@
 #include <string>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     {
@@ -32,4 +32,6 @@ int main()
         assert(in[4] == L'A');
         assert(in[5] == L'1');
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/locale.ctype.members/widen_1.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/locale.ctype.members/widen_1.pass.cpp
index 1737de8f0f7..c2570a31136 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/locale.ctype.members/widen_1.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/locale.ctype.members/widen_1.pass.cpp
@@ -15,7 +15,7 @@
 #include <locale>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     {
@@ -29,4 +29,6 @@ int main()
         assert(f.widen('a') == L'a');
         assert(f.widen('1') == L'1');
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/locale.ctype.members/widen_many.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/locale.ctype.members/widen_many.pass.cpp
index 3942268ebd2..a43817a25a1 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/locale.ctype.members/widen_many.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/locale.ctype.members/widen_many.pass.cpp
@@ -17,7 +17,7 @@
 #include <vector>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     {
@@ -34,4 +34,6 @@ int main()
         assert(v[4] == L'a');
         assert(v[5] == L'1');
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/locale.ctype.virtuals/tested_elsewhere.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/locale.ctype.virtuals/tested_elsewhere.pass.cpp
index f77636c8475..1f764da05d6 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/locale.ctype.virtuals/tested_elsewhere.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/locale.ctype.virtuals/tested_elsewhere.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/types.pass.cpp b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/types.pass.cpp
index 89ac905a2e5..35b5d3282b9 100644
--- a/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/types.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.ctype/locale.ctype/types.pass.cpp
@@ -21,7 +21,7 @@
 #include <type_traits>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     {
@@ -35,4 +35,6 @@ int main()
         static_assert((std::is_base_of<std::ctype_base, std::ctype<wchar_t> >::value), "");
         static_assert((std::is_base_of<std::locale::facet, std::ctype<wchar_t> >::value), "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.messages/locale.messages.byname/nothing_to_do.pass.cpp b/libcxx/test/std/localization/locale.categories/category.messages/locale.messages.byname/nothing_to_do.pass.cpp
index f77636c8475..1f764da05d6 100644
--- a/libcxx/test/std/localization/locale.categories/category.messages/locale.messages.byname/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.messages/locale.messages.byname/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.messages/locale.messages/ctor.pass.cpp b/libcxx/test/std/localization/locale.categories/category.messages/locale.messages/ctor.pass.cpp
index df42b522c7b..ddbbe66694b 100644
--- a/libcxx/test/std/localization/locale.categories/category.messages/locale.messages/ctor.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.messages/locale.messages/ctor.pass.cpp
@@ -31,7 +31,7 @@ public:
 
 int my_facet::count = 0;
 
-int main()
+int main(int, char**)
 {
     {
         std::locale l(std::locale::classic(), new my_facet);
@@ -48,4 +48,6 @@ int main()
         assert(my_facet::count == 1);
     }
     assert(my_facet::count == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.messages/locale.messages/locale.messages.members/not_testable.pass.cpp b/libcxx/test/std/localization/locale.categories/category.messages/locale.messages/locale.messages.members/not_testable.pass.cpp
index 994a97211a4..c0166f80f34 100644
--- a/libcxx/test/std/localization/locale.categories/category.messages/locale.messages/locale.messages.members/not_testable.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.messages/locale.messages/locale.messages.members/not_testable.pass.cpp
@@ -28,6 +28,8 @@ public:
         : std::messages<CharT>(refs) {}
 };
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.messages/locale.messages/locale.messages.virtuals/tested_elsewhere.pass.cpp b/libcxx/test/std/localization/locale.categories/category.messages/locale.messages/locale.messages.virtuals/tested_elsewhere.pass.cpp
index f77636c8475..1f764da05d6 100644
--- a/libcxx/test/std/localization/locale.categories/category.messages/locale.messages/locale.messages.virtuals/tested_elsewhere.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.messages/locale.messages/locale.messages.virtuals/tested_elsewhere.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.messages/locale.messages/messages_base.pass.cpp b/libcxx/test/std/localization/locale.categories/category.messages/locale.messages/messages_base.pass.cpp
index 7f2e4f9b9ab..ce6d70be728 100644
--- a/libcxx/test/std/localization/locale.categories/category.messages/locale.messages/messages_base.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.messages/locale.messages/messages_base.pass.cpp
@@ -17,7 +17,9 @@
 #include <locale>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     std::messages_base mb;
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.messages/locale.messages/types.pass.cpp b/libcxx/test/std/localization/locale.categories/category.messages/locale.messages/types.pass.cpp
index 454d9b18242..436290698cc 100644
--- a/libcxx/test/std/localization/locale.categories/category.messages/locale.messages/types.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.messages/locale.messages/types.pass.cpp
@@ -20,7 +20,7 @@
 #include <locale>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_base_of<std::locale::facet, std::messages<char> >::value), "");
     static_assert((std::is_base_of<std::messages_base, std::messages<char> >::value), "");
@@ -30,4 +30,6 @@ int main()
     static_assert((std::is_same<std::messages<wchar_t>::char_type, wchar_t>::value), "");
     static_assert((std::is_same<std::messages<char>::string_type, std::string>::value), "");
     static_assert((std::is_same<std::messages<wchar_t>::string_type, std::wstring>::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.messages/nothing_to_do.pass.cpp b/libcxx/test/std/localization/locale.categories/category.messages/nothing_to_do.pass.cpp
index f77636c8475..1f764da05d6 100644
--- a/libcxx/test/std/localization/locale.categories/category.messages/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.messages/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.get/ctor.pass.cpp b/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.get/ctor.pass.cpp
index f70f8eeadd3..360ff3ad61f 100644
--- a/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.get/ctor.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.get/ctor.pass.cpp
@@ -31,7 +31,7 @@ public:
 
 int my_facet::count = 0;
 
-int main()
+int main(int, char**)
 {
     {
         std::locale l(std::locale::classic(), new my_facet);
@@ -48,4 +48,6 @@ int main()
         assert(my_facet::count == 1);
     }
     assert(my_facet::count == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.get/locale.money.get.members/get_long_double_en_US.pass.cpp b/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.get/locale.money.get.members/get_long_double_en_US.pass.cpp
index 94f9bd7a9a6..9fec21f51b9 100644
--- a/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.get/locale.money.get.members/get_long_double_en_US.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.get/locale.money.get.members/get_long_double_en_US.pass.cpp
@@ -43,7 +43,7 @@ public:
         : Fw(refs) {}
 };
 
-int main()
+int main(int, char**)
 {
     std::ios ios(0);
     std::string loc_name(LOCALE_en_US_UTF_8);
@@ -719,4 +719,6 @@ int main()
             assert(err == std::ios_base::failbit);
         }
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.get/locale.money.get.members/get_long_double_fr_FR.pass.cpp b/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.get/locale.money.get.members/get_long_double_fr_FR.pass.cpp
index 27ae11eed57..292f5eaea92 100644
--- a/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.get/locale.money.get.members/get_long_double_fr_FR.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.get/locale.money.get.members/get_long_double_fr_FR.pass.cpp
@@ -76,7 +76,7 @@ static std::wstring convert_thousands_sep(std::wstring const& in) {
 #endif
 }
 
-int main()
+int main(int, char**)
 {
     std::ios ios(0);
     std::string loc_name(LOCALE_fr_FR_UTF_8);
@@ -753,4 +753,6 @@ int main()
             assert(ex == 123456789);
         }
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.get/locale.money.get.members/get_long_double_ru_RU.pass.cpp b/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.get/locale.money.get.members/get_long_double_ru_RU.pass.cpp
index b543799accb..c13849804fc 100644
--- a/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.get/locale.money.get.members/get_long_double_ru_RU.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.get/locale.money.get.members/get_long_double_ru_RU.pass.cpp
@@ -55,7 +55,7 @@ public:
         : Fw(refs) {}
 };
 
-int main()
+int main(int, char**)
 {
     std::ios ios(0);
     std::string loc_name(LOCALE_ru_RU_UTF_8);
@@ -735,4 +735,6 @@ int main()
             assert(ex == -123456789);
         }
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.get/locale.money.get.members/get_long_double_zh_CN.pass.cpp b/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.get/locale.money.get.members/get_long_double_zh_CN.pass.cpp
index 20ba6f4914a..9b006f55b7a 100644
--- a/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.get/locale.money.get.members/get_long_double_zh_CN.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.get/locale.money.get.members/get_long_double_zh_CN.pass.cpp
@@ -49,7 +49,7 @@ public:
         : Fw(refs) {}
 };
 
-int main()
+int main(int, char**)
 {
     std::ios ios(0);
     std::string loc_name(LOCALE_zh_CN_UTF_8);
@@ -725,4 +725,6 @@ int main()
             assert(err == std::ios_base::failbit);
         }
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.get/locale.money.get.members/get_string_en_US.pass.cpp b/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.get/locale.money.get.members/get_string_en_US.pass.cpp
index a5cb05334c4..1b1a471e185 100644
--- a/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.get/locale.money.get.members/get_string_en_US.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.get/locale.money.get.members/get_string_en_US.pass.cpp
@@ -43,7 +43,7 @@ public:
         : Fw(refs) {}
 };
 
-int main()
+int main(int, char**)
 {
     std::ios ios(0);
     std::string loc_name(LOCALE_en_US_UTF_8);
@@ -727,4 +727,6 @@ int main()
             assert(ex == L"");
         }
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.get/locale.money.get.virtuals/tested_elsewhere.pass.cpp b/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.get/locale.money.get.virtuals/tested_elsewhere.pass.cpp
index f77636c8475..1f764da05d6 100644
--- a/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.get/locale.money.get.virtuals/tested_elsewhere.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.get/locale.money.get.virtuals/tested_elsewhere.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.get/types.pass.cpp b/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.get/types.pass.cpp
index 9ad7528c205..7bc04801efa 100644
--- a/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.get/types.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.get/types.pass.cpp
@@ -20,7 +20,7 @@
 #include <locale>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_base_of<std::locale::facet, std::money_get<char> >::value), "");
     static_assert((std::is_base_of<std::locale::facet, std::money_get<wchar_t> >::value), "");
@@ -30,4 +30,6 @@ int main()
     static_assert((std::is_same<std::money_get<wchar_t>::iter_type, std::istreambuf_iterator<wchar_t> >::value), "");
     static_assert((std::is_same<std::money_get<char>::string_type, std::string>::value), "");
     static_assert((std::is_same<std::money_get<wchar_t>::string_type, std::wstring>::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.put/ctor.pass.cpp b/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.put/ctor.pass.cpp
index bdbb0b6cd60..309d26c5d74 100644
--- a/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.put/ctor.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.put/ctor.pass.cpp
@@ -31,7 +31,7 @@ public:
 
 int my_facet::count = 0;
 
-int main()
+int main(int, char**)
 {
     {
         std::locale l(std::locale::classic(), new my_facet);
@@ -48,4 +48,6 @@ int main()
         assert(my_facet::count == 1);
     }
     assert(my_facet::count == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.put/locale.money.put.members/put_long_double_en_US.pass.cpp b/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.put/locale.money.put.members/put_long_double_en_US.pass.cpp
index 28f7451e909..d6e4d6cc1d9 100644
--- a/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.put/locale.money.put.members/put_long_double_en_US.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.put/locale.money.put.members/put_long_double_en_US.pass.cpp
@@ -43,7 +43,7 @@ public:
         : Fw(refs) {}
 };
 
-int main()
+int main(int, char**)
 {
     std::ios ios(0);
     std::string loc_name(LOCALE_en_US_UTF_8);
@@ -490,4 +490,6 @@ int main()
         assert(ios.width() == 0);
     }
 }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.put/locale.money.put.members/put_long_double_fr_FR.pass.cpp b/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.put/locale.money.put.members/put_long_double_fr_FR.pass.cpp
index e9e916a3ce5..72f3f65706f 100644
--- a/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.put/locale.money.put.members/put_long_double_fr_FR.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.put/locale.money.put.members/put_long_double_fr_FR.pass.cpp
@@ -78,7 +78,7 @@ static std::wstring convert_thousands_sep(std::wstring const& in) {
 #endif
 }
 
-int main()
+int main(int, char**)
 {
     std::ios ios(0);
     std::string loc_name(LOCALE_fr_FR_UTF_8);
@@ -524,4 +524,6 @@ int main()
         assert(ios.width() == 0);
     }
 }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.put/locale.money.put.members/put_long_double_ru_RU.pass.cpp b/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.put/locale.money.put.members/put_long_double_ru_RU.pass.cpp
index 1894144db62..36f97b1d816 100644
--- a/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.put/locale.money.put.members/put_long_double_ru_RU.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.put/locale.money.put.members/put_long_double_ru_RU.pass.cpp
@@ -55,7 +55,7 @@ public:
         : Fw(refs) {}
 };
 
-int main()
+int main(int, char**)
 {
     std::ios ios(0);
     std::string loc_name(LOCALE_ru_RU_UTF_8);
@@ -501,4 +501,6 @@ int main()
         assert(ios.width() == 0);
     }
 }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.put/locale.money.put.members/put_long_double_zh_CN.pass.cpp b/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.put/locale.money.put.members/put_long_double_zh_CN.pass.cpp
index 0a3d478ec67..a300ba84752 100644
--- a/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.put/locale.money.put.members/put_long_double_zh_CN.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.put/locale.money.put.members/put_long_double_zh_CN.pass.cpp
@@ -49,7 +49,7 @@ public:
         : Fw(refs) {}
 };
 
-int main()
+int main(int, char**)
 {
     std::ios ios(0);
     std::string loc_name(LOCALE_zh_CN_UTF_8);
@@ -495,4 +495,6 @@ int main()
         assert(ios.width() == 0);
     }
 }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.put/locale.money.put.members/put_string_en_US.pass.cpp b/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.put/locale.money.put.members/put_string_en_US.pass.cpp
index ab4a5c6034b..cd1ff643f83 100644
--- a/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.put/locale.money.put.members/put_string_en_US.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.put/locale.money.put.members/put_string_en_US.pass.cpp
@@ -43,7 +43,7 @@ public:
         : Fw(refs) {}
 };
 
-int main()
+int main(int, char**)
 {
     std::ios ios(0);
     std::string loc_name(LOCALE_en_US_UTF_8);
@@ -490,4 +490,6 @@ int main()
         assert(ios.width() == 0);
     }
 }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.put/locale.money.put.virtuals/tested_elsewhere.pass.cpp b/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.put/locale.money.put.virtuals/tested_elsewhere.pass.cpp
index f77636c8475..1f764da05d6 100644
--- a/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.put/locale.money.put.virtuals/tested_elsewhere.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.put/locale.money.put.virtuals/tested_elsewhere.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.put/types.pass.cpp b/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.put/types.pass.cpp
index 27c2ff5d6b3..bd797313c85 100644
--- a/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.put/types.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.monetary/locale.money.put/types.pass.cpp
@@ -20,7 +20,7 @@
 #include <locale>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_base_of<std::locale::facet, std::money_put<char> >::value), "");
     static_assert((std::is_base_of<std::locale::facet, std::money_put<wchar_t> >::value), "");
@@ -30,4 +30,6 @@ int main()
     static_assert((std::is_same<std::money_put<wchar_t>::iter_type, std::ostreambuf_iterator<wchar_t> >::value), "");
     static_assert((std::is_same<std::money_put<char>::string_type, std::string>::value), "");
     static_assert((std::is_same<std::money_put<wchar_t>::string_type, std::wstring>::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct.byname/curr_symbol.pass.cpp b/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct.byname/curr_symbol.pass.cpp
index f04ff4fb614..43a2fbc173d 100644
--- a/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct.byname/curr_symbol.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct.byname/curr_symbol.pass.cpp
@@ -75,7 +75,7 @@ static bool glibc_version_less_than(char const* version) {
 }
 #endif
 
-int main()
+int main(int, char**)
 {
     {
         Fnf f("C", 1);
@@ -179,4 +179,6 @@ int main()
         Fwt f(LOCALE_zh_CN_UTF_8, 1);
         assert(f.curr_symbol() == L"CNY ");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct.byname/decimal_point.pass.cpp b/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct.byname/decimal_point.pass.cpp
index a64388ca5ce..bec52e6abc0 100644
--- a/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct.byname/decimal_point.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct.byname/decimal_point.pass.cpp
@@ -56,7 +56,7 @@ public:
         : std::moneypunct_byname<wchar_t, true>(nm, refs) {}
 };
 
-int main()
+int main(int, char**)
 {
     {
         Fnf f("C", 1);
@@ -153,4 +153,6 @@ int main()
         Fwt f(LOCALE_zh_CN_UTF_8, 1);
         assert(f.decimal_point() == L'.');
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct.byname/frac_digits.pass.cpp b/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct.byname/frac_digits.pass.cpp
index 9bbc76868a8..07d78229a4f 100644
--- a/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct.byname/frac_digits.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct.byname/frac_digits.pass.cpp
@@ -55,7 +55,7 @@ public:
         : std::moneypunct_byname<wchar_t, true>(nm, refs) {}
 };
 
-int main()
+int main(int, char**)
 {
     {
         Fnf f("C", 1);
@@ -141,4 +141,6 @@ int main()
         Fwt f(LOCALE_zh_CN_UTF_8, 1);
         assert(f.frac_digits() == 2);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct.byname/grouping.pass.cpp b/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct.byname/grouping.pass.cpp
index 7ff50db737f..2c2da48642e 100644
--- a/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct.byname/grouping.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct.byname/grouping.pass.cpp
@@ -60,7 +60,7 @@ public:
         : std::moneypunct_byname<wchar_t, true>(nm, refs) {}
 };
 
-int main()
+int main(int, char**)
 {
     // Monetary grouping strings may be terminated with 0 or CHAR_MAX, defining
     // how the grouping is repeated.
@@ -149,4 +149,6 @@ int main()
         Fwt f(LOCALE_zh_CN_UTF_8, 1);
         assert(f.grouping() == "\3");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct.byname/neg_format.pass.cpp b/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct.byname/neg_format.pass.cpp
index 6cd00de657c..f3f637b60df 100644
--- a/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct.byname/neg_format.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct.byname/neg_format.pass.cpp
@@ -60,7 +60,7 @@ public:
         : std::moneypunct_byname<wchar_t, true>(nm, refs) {}
 };
 
-int main()
+int main(int, char**)
 {
     {
         Fnf f("C", 1);
@@ -226,4 +226,6 @@ int main()
         assert(p.field[2] == std::money_base::none);
         assert(p.field[3] == std::money_base::value);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct.byname/negative_sign.pass.cpp b/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct.byname/negative_sign.pass.cpp
index 6857810bd03..5567fc08eb5 100644
--- a/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct.byname/negative_sign.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct.byname/negative_sign.pass.cpp
@@ -55,7 +55,7 @@ public:
         : std::moneypunct_byname<wchar_t, true>(nm, refs) {}
 };
 
-int main()
+int main(int, char**)
 {
     {
         Fnf f("C", 1);
@@ -141,4 +141,6 @@ int main()
         Fwt f(LOCALE_zh_CN_UTF_8, 1);
         assert(f.negative_sign() == L"-");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct.byname/pos_format.pass.cpp b/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct.byname/pos_format.pass.cpp
index ff3cdcdb2fd..f7d396a6625 100644
--- a/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct.byname/pos_format.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct.byname/pos_format.pass.cpp
@@ -60,7 +60,7 @@ public:
         : std::moneypunct_byname<wchar_t, true>(nm, refs) {}
 };
 
-int main()
+int main(int, char**)
 {
     {
         Fnf f("C", 1);
@@ -226,4 +226,6 @@ int main()
         assert(p.field[2] == std::money_base::none);
         assert(p.field[3] == std::money_base::value);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct.byname/positive_sign.pass.cpp b/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct.byname/positive_sign.pass.cpp
index 50a7ca939ba..43dfa2a2f18 100644
--- a/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct.byname/positive_sign.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct.byname/positive_sign.pass.cpp
@@ -55,7 +55,7 @@ public:
         : std::moneypunct_byname<wchar_t, true>(nm, refs) {}
 };
 
-int main()
+int main(int, char**)
 {
     {
         Fnf f("C", 1);
@@ -141,4 +141,6 @@ int main()
         Fwt f(LOCALE_zh_CN_UTF_8, 1);
         assert(f.positive_sign() == L"");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct.byname/thousands_sep.pass.cpp b/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct.byname/thousands_sep.pass.cpp
index e0bfd88a8bf..c789c4e5b1b 100644
--- a/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct.byname/thousands_sep.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct.byname/thousands_sep.pass.cpp
@@ -59,7 +59,7 @@ public:
         : std::moneypunct_byname<wchar_t, true>(nm, refs) {}
 };
 
-int main()
+int main(int, char**)
 {
     {
         Fnf f("C", 1);
@@ -170,4 +170,6 @@ int main()
         Fwt f(LOCALE_zh_CN_UTF_8, 1);
         assert(f.thousands_sep() == L',');
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct/ctor.pass.cpp b/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct/ctor.pass.cpp
index 4717d4c0f1d..3b52f7afc74 100644
--- a/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct/ctor.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct/ctor.pass.cpp
@@ -31,7 +31,7 @@ public:
 
 int my_facet::count = 0;
 
-int main()
+int main(int, char**)
 {
     {
         std::locale l(std::locale::classic(), new my_facet);
@@ -48,4 +48,6 @@ int main()
         assert(my_facet::count == 1);
     }
     assert(my_facet::count == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct/locale.moneypunct.members/curr_symbol.pass.cpp b/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct/locale.moneypunct.members/curr_symbol.pass.cpp
index 57732242586..7b3b75a19c2 100644
--- a/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct/locale.moneypunct.members/curr_symbol.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct/locale.moneypunct.members/curr_symbol.pass.cpp
@@ -53,7 +53,7 @@ public:
         : std::moneypunct<wchar_t, true>(refs) {}
 };
 
-int main()
+int main(int, char**)
 {
     {
         Fnf f(1);
@@ -71,4 +71,6 @@ int main()
         Fwt f(1);
         assert(f.curr_symbol() == std::wstring());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct/locale.moneypunct.members/decimal_point.pass.cpp b/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct/locale.moneypunct.members/decimal_point.pass.cpp
index 206f325354d..34d02032cc9 100644
--- a/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct/locale.moneypunct.members/decimal_point.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct/locale.moneypunct.members/decimal_point.pass.cpp
@@ -53,7 +53,7 @@ public:
         : std::moneypunct<wchar_t, true>(refs) {}
 };
 
-int main()
+int main(int, char**)
 {
     {
         Fnf f(1);
@@ -71,4 +71,6 @@ int main()
         Fwt f(1);
         assert(f.decimal_point() == std::numeric_limits<wchar_t>::max());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct/locale.moneypunct.members/frac_digits.pass.cpp b/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct/locale.moneypunct.members/frac_digits.pass.cpp
index b27ecd6df9f..50365584d24 100644
--- a/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct/locale.moneypunct.members/frac_digits.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct/locale.moneypunct.members/frac_digits.pass.cpp
@@ -53,7 +53,7 @@ public:
         : std::moneypunct<wchar_t, true>(refs) {}
 };
 
-int main()
+int main(int, char**)
 {
     {
         Fnf f(1);
@@ -71,4 +71,6 @@ int main()
         Fwt f(1);
         assert(f.frac_digits() == 0);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct/locale.moneypunct.members/grouping.pass.cpp b/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct/locale.moneypunct.members/grouping.pass.cpp
index e959ad8abad..9e12e322044 100644
--- a/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct/locale.moneypunct.members/grouping.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct/locale.moneypunct.members/grouping.pass.cpp
@@ -53,7 +53,7 @@ public:
         : std::moneypunct<wchar_t, true>(refs) {}
 };
 
-int main()
+int main(int, char**)
 {
     {
         Fnf f(1);
@@ -71,4 +71,6 @@ int main()
         Fwt f(1);
         assert(f.grouping() == std::string());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct/locale.moneypunct.members/neg_format.pass.cpp b/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct/locale.moneypunct.members/neg_format.pass.cpp
index e9950b1a78e..cb511990959 100644
--- a/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct/locale.moneypunct.members/neg_format.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct/locale.moneypunct.members/neg_format.pass.cpp
@@ -50,7 +50,7 @@ public:
         : std::moneypunct<wchar_t, true>(refs) {}
 };
 
-int main()
+int main(int, char**)
 {
     {
         Fnf f(1);
@@ -84,4 +84,6 @@ int main()
         assert(p.field[2] == std::money_base::none);
         assert(p.field[3] == std::money_base::value);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct/locale.moneypunct.members/negative_sign.pass.cpp b/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct/locale.moneypunct.members/negative_sign.pass.cpp
index 3ef5e84fc05..6f134e7847e 100644
--- a/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct/locale.moneypunct.members/negative_sign.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct/locale.moneypunct.members/negative_sign.pass.cpp
@@ -54,7 +54,7 @@ public:
         : std::moneypunct<wchar_t, true>(refs) {}
 };
 
-int main()
+int main(int, char**)
 {
     {
         Fnf f(1);
@@ -72,4 +72,6 @@ int main()
         Fwt f(1);
         assert(f.negative_sign() == L"-");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct/locale.moneypunct.members/pos_format.pass.cpp b/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct/locale.moneypunct.members/pos_format.pass.cpp
index 3c3034bbe9d..bff44a69d88 100644
--- a/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct/locale.moneypunct.members/pos_format.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct/locale.moneypunct.members/pos_format.pass.cpp
@@ -50,7 +50,7 @@ public:
         : std::moneypunct<wchar_t, true>(refs) {}
 };
 
-int main()
+int main(int, char**)
 {
     {
         Fnf f(1);
@@ -84,4 +84,6 @@ int main()
         assert(p.field[2] == std::money_base::none);
         assert(p.field[3] == std::money_base::value);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct/locale.moneypunct.members/positive_sign.pass.cpp b/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct/locale.moneypunct.members/positive_sign.pass.cpp
index dbe3e4ba786..8686e20051b 100644
--- a/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct/locale.moneypunct.members/positive_sign.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct/locale.moneypunct.members/positive_sign.pass.cpp
@@ -53,7 +53,7 @@ public:
         : std::moneypunct<wchar_t, true>(refs) {}
 };
 
-int main()
+int main(int, char**)
 {
     {
         Fnf f(1);
@@ -71,4 +71,6 @@ int main()
         Fwt f(1);
         assert(f.positive_sign() == std::wstring());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct/locale.moneypunct.members/thousands_sep.pass.cpp b/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct/locale.moneypunct.members/thousands_sep.pass.cpp
index 7b24c6dc9ed..42d28d09656 100644
--- a/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct/locale.moneypunct.members/thousands_sep.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct/locale.moneypunct.members/thousands_sep.pass.cpp
@@ -53,7 +53,7 @@ public:
         : std::moneypunct<wchar_t, true>(refs) {}
 };
 
-int main()
+int main(int, char**)
 {
     {
         Fnf f(1);
@@ -71,4 +71,6 @@ int main()
         Fwt f(1);
         assert(f.thousands_sep() == std::numeric_limits<wchar_t>::max());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct/locale.moneypunct.virtuals/tested_elsewhere.pass.cpp b/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct/locale.moneypunct.virtuals/tested_elsewhere.pass.cpp
index f77636c8475..1f764da05d6 100644
--- a/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct/locale.moneypunct.virtuals/tested_elsewhere.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct/locale.moneypunct.virtuals/tested_elsewhere.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct/money_base.pass.cpp b/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct/money_base.pass.cpp
index d02c3b43e8a..58f04905a0a 100644
--- a/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct/money_base.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct/money_base.pass.cpp
@@ -18,7 +18,7 @@
 #include <locale>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::money_base mb; ((void)mb);
     static_assert(std::money_base::none == 0, "");
@@ -29,4 +29,6 @@ int main()
     static_assert(sizeof(std::money_base::pattern) == 4, "");
     std::money_base::pattern p;
     p.field[0] = std::money_base::none;
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct/types.pass.cpp b/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct/types.pass.cpp
index 439f8c31f73..24ddadfb3a7 100644
--- a/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct/types.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct/types.pass.cpp
@@ -29,7 +29,7 @@
 template <class T>
 void test(const T &) {}
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_base_of<std::locale::facet, std::moneypunct<char> >::value), "");
     static_assert((std::is_base_of<std::locale::facet, std::moneypunct<wchar_t> >::value), "");
@@ -44,4 +44,6 @@ int main()
     test(std::moneypunct<char, true>::intl);
     test(std::moneypunct<wchar_t, false>::intl);
     test(std::moneypunct<wchar_t, true>::intl);
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.monetary/nothing_to_do.pass.cpp b/libcxx/test/std/localization/locale.categories/category.monetary/nothing_to_do.pass.cpp
index f77636c8475..1f764da05d6 100644
--- a/libcxx/test/std/localization/locale.categories/category.monetary/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.monetary/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.numeric/locale.nm.put/ctor.pass.cpp b/libcxx/test/std/localization/locale.categories/category.numeric/locale.nm.put/ctor.pass.cpp
index afb58d5e214..5a3af4b9536 100644
--- a/libcxx/test/std/localization/locale.categories/category.numeric/locale.nm.put/ctor.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.numeric/locale.nm.put/ctor.pass.cpp
@@ -31,7 +31,7 @@ public:
 
 int my_facet::count = 0;
 
-int main()
+int main(int, char**)
 {
     {
         std::locale l(std::locale::classic(), new my_facet);
@@ -48,4 +48,6 @@ int main()
         assert(my_facet::count == 1);
     }
     assert(my_facet::count == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.numeric/locale.nm.put/facet.num.put.members/put_bool.pass.cpp b/libcxx/test/std/localization/locale.categories/category.numeric/locale.nm.put/facet.num.put.members/put_bool.pass.cpp
index 0c71a735473..79aa68dde8b 100644
--- a/libcxx/test/std/localization/locale.categories/category.numeric/locale.nm.put/facet.num.put.members/put_bool.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.numeric/locale.nm.put/facet.num.put.members/put_bool.pass.cpp
@@ -39,7 +39,7 @@ protected:
     virtual string_type do_falsename() const {return "no";}
 };
 
-int main()
+int main(int, char**)
 {
     const my_facet f(1);
     {
@@ -96,4 +96,6 @@ int main()
             assert(ex == "yes");
         }
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.numeric/locale.nm.put/facet.num.put.members/put_double.pass.cpp b/libcxx/test/std/localization/locale.categories/category.numeric/locale.nm.put/facet.num.put.members/put_double.pass.cpp
index 0d30bbf7096..062d5cfd404 100644
--- a/libcxx/test/std/localization/locale.categories/category.numeric/locale.nm.put/facet.num.put.members/put_double.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.numeric/locale.nm.put/facet.num.put.members/put_double.pass.cpp
@@ -17876,7 +17876,7 @@ void test8()
     }
 }
 
-int main()
+int main(int, char**)
 {
     test1();
     test2();
@@ -17886,4 +17886,6 @@ int main()
     test6();
     test7();
     test8();
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.numeric/locale.nm.put/facet.num.put.members/put_long.pass.cpp b/libcxx/test/std/localization/locale.categories/category.numeric/locale.nm.put/facet.num.put.members/put_long.pass.cpp
index 5cf9bfa1f7a..1aee8bdfe86 100644
--- a/libcxx/test/std/localization/locale.categories/category.numeric/locale.nm.put/facet.num.put.members/put_long.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.numeric/locale.nm.put/facet.num.put.members/put_long.pass.cpp
@@ -39,7 +39,7 @@ protected:
     virtual std::string do_grouping() const {return std::string("\1\2\3");}
 };
 
-int main()
+int main(int, char**)
 {
     const my_facet f(1);
     {
@@ -340,4 +340,6 @@ int main()
         assert(ex == "-***1_00_0");
         assert(ios.width() == 0);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.numeric/locale.nm.put/facet.num.put.members/put_long_double.pass.cpp b/libcxx/test/std/localization/locale.categories/category.numeric/locale.nm.put/facet.num.put.members/put_long_double.pass.cpp
index 5fcc0e4646b..3e71a1dfbfb 100644
--- a/libcxx/test/std/localization/locale.categories/category.numeric/locale.nm.put/facet.num.put.members/put_long_double.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.numeric/locale.nm.put/facet.num.put.members/put_long_double.pass.cpp
@@ -26206,7 +26206,7 @@ void test12()
 #endif
 }
 
-int main()
+int main(int, char**)
 {
     test1();
     test2();
@@ -26246,4 +26246,6 @@ int main()
     {
         long double v = std::nan(""); ((void)v);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.numeric/locale.nm.put/facet.num.put.members/put_long_long.pass.cpp b/libcxx/test/std/localization/locale.categories/category.numeric/locale.nm.put/facet.num.put.members/put_long_long.pass.cpp
index 18d96754be7..a3c49d36ae6 100644
--- a/libcxx/test/std/localization/locale.categories/category.numeric/locale.nm.put/facet.num.put.members/put_long_long.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.numeric/locale.nm.put/facet.num.put.members/put_long_long.pass.cpp
@@ -39,7 +39,7 @@ protected:
     virtual std::string do_grouping() const {return std::string("\1\2\3");}
 };
 
-int main()
+int main(int, char**)
 {
     const my_facet f(1);
     {
@@ -340,4 +340,6 @@ int main()
         assert(ex == "-***1_00_0");
         assert(ios.width() == 0);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.numeric/locale.nm.put/facet.num.put.members/put_pointer.pass.cpp b/libcxx/test/std/localization/locale.categories/category.numeric/locale.nm.put/facet.num.put.members/put_pointer.pass.cpp
index f4fdf762067..d366c3842bf 100644
--- a/libcxx/test/std/localization/locale.categories/category.numeric/locale.nm.put/facet.num.put.members/put_pointer.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.numeric/locale.nm.put/facet.num.put.members/put_pointer.pass.cpp
@@ -28,7 +28,7 @@ public:
         : F(refs) {}
 };
 
-int main()
+int main(int, char**)
 {
     const my_facet f(1);
     {
@@ -45,4 +45,6 @@ int main()
         assert(rc > 0);
         assert(ex == expected_str);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.numeric/locale.nm.put/facet.num.put.members/put_unsigned_long.pass.cpp b/libcxx/test/std/localization/locale.categories/category.numeric/locale.nm.put/facet.num.put.members/put_unsigned_long.pass.cpp
index 98aba106cc1..420d22fb028 100644
--- a/libcxx/test/std/localization/locale.categories/category.numeric/locale.nm.put/facet.num.put.members/put_unsigned_long.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.numeric/locale.nm.put/facet.num.put.members/put_unsigned_long.pass.cpp
@@ -39,7 +39,7 @@ protected:
     virtual std::string do_grouping() const {return std::string("\1\2\3");}
 };
 
-int main()
+int main(int, char**)
 {
     const my_facet f(1);
     {
@@ -343,4 +343,6 @@ int main()
                                                  : "18_446_744_073_709_550_61_6"));
         assert(ios.width() == 0);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.numeric/locale.nm.put/facet.num.put.members/put_unsigned_long_long.pass.cpp b/libcxx/test/std/localization/locale.categories/category.numeric/locale.nm.put/facet.num.put.members/put_unsigned_long_long.pass.cpp
index ccebb6ce1a4..1ad3065c074 100644
--- a/libcxx/test/std/localization/locale.categories/category.numeric/locale.nm.put/facet.num.put.members/put_unsigned_long_long.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.numeric/locale.nm.put/facet.num.put.members/put_unsigned_long_long.pass.cpp
@@ -39,7 +39,7 @@ protected:
     virtual std::string do_grouping() const {return std::string("\1\2\3");}
 };
 
-int main()
+int main(int, char**)
 {
     const my_facet f(1);
     {
@@ -340,4 +340,6 @@ int main()
         assert(ex == "18_446_744_073_709_550_61_6");
         assert(ios.width() == 0);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.numeric/locale.nm.put/facet.num.put.virtuals/tested_elsewhere.pass.cpp b/libcxx/test/std/localization/locale.categories/category.numeric/locale.nm.put/facet.num.put.virtuals/tested_elsewhere.pass.cpp
index f77636c8475..1f764da05d6 100644
--- a/libcxx/test/std/localization/locale.categories/category.numeric/locale.nm.put/facet.num.put.virtuals/tested_elsewhere.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.numeric/locale.nm.put/facet.num.put.virtuals/tested_elsewhere.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.numeric/locale.nm.put/types.pass.cpp b/libcxx/test/std/localization/locale.categories/category.numeric/locale.nm.put/types.pass.cpp
index 19e8ceeb025..6011c75c1fe 100644
--- a/libcxx/test/std/localization/locale.categories/category.numeric/locale.nm.put/types.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.numeric/locale.nm.put/types.pass.cpp
@@ -20,7 +20,7 @@
 #include <iterator>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_base_of<std::locale::facet, std::num_put<char> >::value), "");
     static_assert((std::is_base_of<std::locale::facet, std::num_put<wchar_t> >::value), "");
@@ -28,4 +28,6 @@ int main()
     static_assert((std::is_same<std::num_put<wchar_t>::char_type, wchar_t>::value), "");
     static_assert((std::is_same<std::num_put<char>::iter_type, std::ostreambuf_iterator<char> >::value), "");
     static_assert((std::is_same<std::num_put<wchar_t>::iter_type, std::ostreambuf_iterator<wchar_t> >::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/ctor.pass.cpp b/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/ctor.pass.cpp
index 2929fb05e1f..096939d0842 100644
--- a/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/ctor.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/ctor.pass.cpp
@@ -31,7 +31,7 @@ public:
 
 int my_facet::count = 0;
 
-int main()
+int main(int, char**)
 {
     {
         std::locale l(std::locale::classic(), new my_facet);
@@ -48,4 +48,6 @@ int main()
         assert(my_facet::count == 1);
     }
     assert(my_facet::count == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.members/get_bool.pass.cpp b/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.members/get_bool.pass.cpp
index 8b4a33e8471..b577d96b73c 100644
--- a/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.members/get_bool.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.members/get_bool.pass.cpp
@@ -51,7 +51,7 @@ protected:
     virtual string_type do_falsename() const {return "ab";}
 };
 
-int main()
+int main(int, char**)
 {
     const my_facet f(1);
     std::ios ios(0);
@@ -226,4 +226,6 @@ int main()
         assert(err == ios.goodbit);
         assert(b == true);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.members/get_double.pass.cpp b/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.members/get_double.pass.cpp
index 7e896f705c0..3980d488d96 100644
--- a/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.members/get_double.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.members/get_double.pass.cpp
@@ -48,7 +48,7 @@ protected:
     virtual std::string do_grouping() const {return std::string("\1\2\3");}
 };
 
-int main()
+int main(int, char**)
 {
     const my_facet f(1);
     std::ios ios(0);
@@ -278,4 +278,6 @@ int main()
         assert(err == ios.goodbit);
         assert(std::abs(v - 3.14159265358979e+10)/3.14159265358979e+10 < 1.e-8);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.members/get_float.pass.cpp b/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.members/get_float.pass.cpp
index aa7ffcb7809..1ac313f7d7a 100644
--- a/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.members/get_float.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.members/get_float.pass.cpp
@@ -35,7 +35,7 @@ public:
 };
 
 
-int main()
+int main(int, char**)
 {
     const my_facet f(1);
     std::ios ios(0);
@@ -208,4 +208,6 @@ int main()
         assert(err == ios.goodbit);
         assert(v == 2);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.members/get_long.pass.cpp b/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.members/get_long.pass.cpp
index 02f2ba6dcb1..13511728678 100644
--- a/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.members/get_long.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.members/get_long.pass.cpp
@@ -41,7 +41,7 @@ protected:
     virtual std::string do_grouping() const {return std::string("\1\2\3");}
 };
 
-int main()
+int main(int, char**)
 {
     const my_facet f(1);
     std::ios ios(0);
@@ -517,4 +517,6 @@ int main()
         assert(err == ios.failbit);
         assert(v == std::numeric_limits<long>::max());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.members/get_long_double.pass.cpp b/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.members/get_long_double.pass.cpp
index 89fa436a909..49e8ae750d9 100644
--- a/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.members/get_long_double.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.members/get_long_double.pass.cpp
@@ -35,7 +35,7 @@ public:
 };
 
 
-int main()
+int main(int, char**)
 {
     const my_facet f(1);
     std::ios ios(0);
@@ -267,4 +267,6 @@ int main()
         assert(err == ios.goodbit);
         assert(v == 2);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.members/get_long_long.pass.cpp b/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.members/get_long_long.pass.cpp
index 9f8153c6b28..c3a66a9836a 100644
--- a/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.members/get_long_long.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.members/get_long_long.pass.cpp
@@ -40,7 +40,7 @@ protected:
     virtual std::string do_grouping() const {return std::string("\1\2\3");}
 };
 
-int main()
+int main(int, char**)
 {
     const my_facet f(1);
     std::ios ios(0);
@@ -102,4 +102,6 @@ int main()
         const long long expect = 0x8000000000000000LL;
         assert(v == expect);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.members/get_pointer.pass.cpp b/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.members/get_pointer.pass.cpp
index 2388dce5fb7..23b6ad932d6 100644
--- a/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.members/get_pointer.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.members/get_pointer.pass.cpp
@@ -29,7 +29,7 @@ public:
         : F(refs) {}
 };
 
-int main()
+int main(int, char**)
 {
     const my_facet f(1);
     std::ios ios(0);
@@ -57,4 +57,6 @@ int main()
         assert(err == ios.goodbit);
         assert(p == (void*)0x73);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.members/get_unsigned_int.pass.cpp b/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.members/get_unsigned_int.pass.cpp
index 36aafc2f484..8a1ee3914f7 100644
--- a/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.members/get_unsigned_int.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.members/get_unsigned_int.pass.cpp
@@ -40,7 +40,7 @@ protected:
     virtual std::string do_grouping() const {return std::string("\1\2\3");}
 };
 
-int main()
+int main(int, char**)
 {
     const my_facet f(1);
     std::ios ios(0);
@@ -79,4 +79,6 @@ int main()
         assert(err == ios.goodbit);
         assert(v == 0xFFFFFFFF);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.members/get_unsigned_long.pass.cpp b/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.members/get_unsigned_long.pass.cpp
index 47b58b34eed..e97c460c7e4 100644
--- a/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.members/get_unsigned_long.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.members/get_unsigned_long.pass.cpp
@@ -40,7 +40,7 @@ protected:
     virtual std::string do_grouping() const {return std::string("\1\2\3");}
 };
 
-int main()
+int main(int, char**)
 {
     const my_facet f(1);
     std::ios ios(0);
@@ -79,4 +79,6 @@ int main()
         assert(err == ios.goodbit);
         assert(v == 0xFFFFFFFF);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.members/get_unsigned_long_long.pass.cpp b/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.members/get_unsigned_long_long.pass.cpp
index 3518c30a038..a5d57df05cc 100644
--- a/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.members/get_unsigned_long_long.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.members/get_unsigned_long_long.pass.cpp
@@ -40,7 +40,7 @@ protected:
     virtual std::string do_grouping() const {return std::string("\1\2\3");}
 };
 
-int main()
+int main(int, char**)
 {
     const my_facet f(1);
     std::ios ios(0);
@@ -79,4 +79,6 @@ int main()
         assert(err == ios.goodbit);
         assert(v == 0xFFFFFFFFFFFFFFFFULL);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.members/get_unsigned_short.pass.cpp b/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.members/get_unsigned_short.pass.cpp
index f83148a1d50..261cac3725f 100644
--- a/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.members/get_unsigned_short.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.members/get_unsigned_short.pass.cpp
@@ -40,7 +40,7 @@ protected:
     virtual std::string do_grouping() const {return std::string("\1\2\3");}
 };
 
-int main()
+int main(int, char**)
 {
     const my_facet f(1);
     std::ios ios(0);
@@ -79,4 +79,6 @@ int main()
         assert(err == ios.goodbit);
         assert(v == 0xFFFF);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.members/test_min_max.pass.cpp b/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.members/test_min_max.pass.cpp
index 5c6de9709b2..92cbeda61bb 100644
--- a/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.members/test_min_max.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.members/test_min_max.pass.cpp
@@ -51,7 +51,7 @@ void check_limits()
     }
 }
 
-int main()
+int main(int, char**)
 {
     check_limits<short>();
     check_limits<unsigned short>();
@@ -61,4 +61,6 @@ int main()
     check_limits<unsigned long>();
     check_limits<long long>();
     check_limits<unsigned long long>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.members/test_neg_one.pass.cpp b/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.members/test_neg_one.pass.cpp
index 4faa4155e48..07a22cb6e55 100644
--- a/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.members/test_neg_one.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.members/test_neg_one.pass.cpp
@@ -148,7 +148,7 @@ void test_negate() {
     }
 }
 
-int main()
+int main(int, char**)
 {
     test_neg_one<long>();
     test_neg_one<long long>();
@@ -161,4 +161,6 @@ int main()
     test_negate<unsigned int>();
     test_negate<unsigned long>();
     test_negate<unsigned long long>();
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.virtuals/tested_elsewhere.pass.cpp b/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.virtuals/tested_elsewhere.pass.cpp
index f77636c8475..1f764da05d6 100644
--- a/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.virtuals/tested_elsewhere.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.virtuals/tested_elsewhere.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/types.pass.cpp b/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/types.pass.cpp
index ab8c00edeb6..42f210d3958 100644
--- a/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/types.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/types.pass.cpp
@@ -20,7 +20,7 @@
 #include <iterator>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_base_of<std::locale::facet, std::num_get<char> >::value), "");
     static_assert((std::is_base_of<std::locale::facet, std::num_get<wchar_t> >::value), "");
@@ -28,4 +28,6 @@ int main()
     static_assert((std::is_same<std::num_get<wchar_t>::char_type, wchar_t>::value), "");
     static_assert((std::is_same<std::num_get<char>::iter_type, std::istreambuf_iterator<char> >::value), "");
     static_assert((std::is_same<std::num_get<wchar_t>::iter_type, std::istreambuf_iterator<wchar_t> >::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.numeric/nothing_to_do.pass.cpp b/libcxx/test/std/localization/locale.categories/category.numeric/nothing_to_do.pass.cpp
index f77636c8475..1f764da05d6 100644
--- a/libcxx/test/std/localization/locale.categories/category.numeric/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.numeric/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get.byname/date_order.pass.cpp b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get.byname/date_order.pass.cpp
index b779be50f47..30624ecc891 100644
--- a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get.byname/date_order.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get.byname/date_order.pass.cpp
@@ -33,7 +33,7 @@ public:
         : F(nm, refs) {}
 };
 
-int main()
+int main(int, char**)
 {
     {
         const my_facet f(LOCALE_en_US_UTF_8, 1);
@@ -51,4 +51,6 @@ int main()
         const my_facet f(LOCALE_zh_CN_UTF_8, 1);
         assert(f.date_order() == std::time_base::ymd);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get.byname/date_order_wide.pass.cpp b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get.byname/date_order_wide.pass.cpp
index 62ca1978488..d62071b94e2 100644
--- a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get.byname/date_order_wide.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get.byname/date_order_wide.pass.cpp
@@ -33,7 +33,7 @@ public:
         : F(nm, refs) {}
 };
 
-int main()
+int main(int, char**)
 {
     {
         const my_facet f(LOCALE_en_US_UTF_8, 1);
@@ -51,4 +51,6 @@ int main()
         const my_facet f(LOCALE_zh_CN_UTF_8, 1);
         assert(f.date_order() == std::time_base::ymd);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get.byname/get_date.pass.cpp b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get.byname/get_date.pass.cpp
index 5c0a5ff59a2..e5b5913256d 100644
--- a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get.byname/get_date.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get.byname/get_date.pass.cpp
@@ -44,7 +44,7 @@ public:
         : F(nm, refs) {}
 };
 
-int main()
+int main(int, char**)
 {
     std::ios ios(0);
     std::ios_base::iostate err;
@@ -98,4 +98,6 @@ int main()
         assert(t.tm_year == 109);
         assert(err == std::ios_base::eofbit);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get.byname/get_date_wide.pass.cpp b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get.byname/get_date_wide.pass.cpp
index 7dd82ed63ac..5506e4cace8 100644
--- a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get.byname/get_date_wide.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get.byname/get_date_wide.pass.cpp
@@ -44,7 +44,7 @@ public:
         : F(nm, refs) {}
 };
 
-int main()
+int main(int, char**)
 {
     std::ios ios(0);
     std::ios_base::iostate err;
@@ -97,4 +97,6 @@ int main()
         assert(t.tm_year == 109);
         assert(err == std::ios_base::eofbit);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get.byname/get_monthname.pass.cpp b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get.byname/get_monthname.pass.cpp
index 787d4a00e9f..5311a856508 100644
--- a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get.byname/get_monthname.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get.byname/get_monthname.pass.cpp
@@ -36,7 +36,7 @@ public:
         : F(nm, refs) {}
 };
 
-int main()
+int main(int, char**)
 {
     std::ios ios(0);
     std::ios_base::iostate err;
@@ -71,4 +71,6 @@ int main()
         assert(t.tm_mon == 5);
         assert(err == std::ios_base::eofbit);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get.byname/get_monthname_wide.pass.cpp b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get.byname/get_monthname_wide.pass.cpp
index a975bc96293..e45260a6690 100644
--- a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get.byname/get_monthname_wide.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get.byname/get_monthname_wide.pass.cpp
@@ -45,7 +45,7 @@ public:
         : F2(nm, refs) {}
 };
 
-int main()
+int main(int, char**)
 {
     std::ios ios(0);
     std::ios_base::iostate err;
@@ -80,4 +80,6 @@ int main()
         assert(t.tm_mon == 5);
         assert(err == std::ios_base::eofbit);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get.byname/get_one.pass.cpp b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get.byname/get_one.pass.cpp
index c63fab2aa74..bda40c56d27 100644
--- a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get.byname/get_one.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get.byname/get_one.pass.cpp
@@ -42,7 +42,7 @@ public:
         : F(nm, refs) {}
 };
 
-int main()
+int main(int, char**)
 {
     std::ios ios(0);
     std::ios_base::iostate err;
@@ -167,4 +167,6 @@ int main()
         assert(t.tm_hour == 23);
         assert(err == std::ios_base::eofbit);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get.byname/get_one_wide.pass.cpp b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get.byname/get_one_wide.pass.cpp
index 6c8d86e12ac..d8715f825d0 100644
--- a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get.byname/get_one_wide.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get.byname/get_one_wide.pass.cpp
@@ -42,7 +42,7 @@ public:
         : F(nm, refs) {}
 };
 
-int main()
+int main(int, char**)
 {
     std::ios ios(0);
     std::ios_base::iostate err;
@@ -169,4 +169,6 @@ int main()
         assert(t.tm_hour == 23);
         assert(err == std::ios_base::eofbit);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get.byname/get_time.pass.cpp b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get.byname/get_time.pass.cpp
index bdb61c66d81..a007415d034 100644
--- a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get.byname/get_time.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get.byname/get_time.pass.cpp
@@ -37,7 +37,7 @@ public:
         : F(nm, refs) {}
 };
 
-int main()
+int main(int, char**)
 {
     std::ios ios(0);
     std::ios_base::iostate err;
@@ -90,4 +90,6 @@ int main()
         assert(t.tm_sec == 15);
         assert(err == std::ios_base::eofbit);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get.byname/get_time_wide.pass.cpp b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get.byname/get_time_wide.pass.cpp
index b0e8b1c39c5..0e2481d6a84 100644
--- a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get.byname/get_time_wide.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get.byname/get_time_wide.pass.cpp
@@ -37,7 +37,7 @@ public:
         : F(nm, refs) {}
 };
 
-int main()
+int main(int, char**)
 {
     std::ios ios(0);
     std::ios_base::iostate err;
@@ -90,4 +90,6 @@ int main()
         assert(t.tm_sec == 15);
         assert(err == std::ios_base::eofbit);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get.byname/get_weekday.pass.cpp b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get.byname/get_weekday.pass.cpp
index 342c87a48bf..308b08529ea 100644
--- a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get.byname/get_weekday.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get.byname/get_weekday.pass.cpp
@@ -40,7 +40,7 @@ public:
         : F(nm, refs) {}
 };
 
-int main()
+int main(int, char**)
 {
     std::ios ios(0);
     std::ios_base::iostate err;
@@ -87,4 +87,6 @@ int main()
         assert(t.tm_wday == 1);
         assert(err == std::ios_base::eofbit);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get.byname/get_weekday_wide.pass.cpp b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get.byname/get_weekday_wide.pass.cpp
index c2566095f73..c52462e37c2 100644
--- a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get.byname/get_weekday_wide.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get.byname/get_weekday_wide.pass.cpp
@@ -40,7 +40,7 @@ public:
         : F(nm, refs) {}
 };
 
-int main()
+int main(int, char**)
 {
     std::ios ios(0);
     std::ios_base::iostate err;
@@ -85,4 +85,6 @@ int main()
         assert(t.tm_wday == 1);
         assert(err == std::ios_base::eofbit);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get.byname/get_year.pass.cpp b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get.byname/get_year.pass.cpp
index a53cd059b98..09df423719a 100644
--- a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get.byname/get_year.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get.byname/get_year.pass.cpp
@@ -36,7 +36,7 @@ public:
         : F(nm, refs) {}
 };
 
-int main()
+int main(int, char**)
 {
     std::ios ios(0);
     std::ios_base::iostate err;
@@ -81,4 +81,6 @@ int main()
         assert(t.tm_year == 109);
         assert(err == std::ios_base::eofbit);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get.byname/get_year_wide.pass.cpp b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get.byname/get_year_wide.pass.cpp
index 93ae51e5559..78c35e969bd 100644
--- a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get.byname/get_year_wide.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get.byname/get_year_wide.pass.cpp
@@ -36,7 +36,7 @@ public:
         : F(nm, refs) {}
 };
 
-int main()
+int main(int, char**)
 {
     std::ios ios(0);
     std::ios_base::iostate err;
@@ -81,4 +81,6 @@ int main()
         assert(t.tm_year == 109);
         assert(err == std::ios_base::eofbit);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/ctor.pass.cpp b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/ctor.pass.cpp
index a920c5cb903..6fb9899de7b 100644
--- a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/ctor.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/ctor.pass.cpp
@@ -31,7 +31,7 @@ public:
 
 int my_facet::count = 0;
 
-int main()
+int main(int, char**)
 {
     {
         std::locale l(std::locale::classic(), new my_facet);
@@ -48,4 +48,6 @@ int main()
         assert(my_facet::count == 1);
     }
     assert(my_facet::count == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/locale.time.get.members/date_order.pass.cpp b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/locale.time.get.members/date_order.pass.cpp
index e14d1c57f37..47b06e9df04 100644
--- a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/locale.time.get.members/date_order.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/locale.time.get.members/date_order.pass.cpp
@@ -26,8 +26,10 @@ public:
         : F(refs) {}
 };
 
-int main()
+int main(int, char**)
 {
     const my_facet f(1);
     assert(f.date_order() == std::time_base::mdy);
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/locale.time.get.members/get_date.pass.cpp b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/locale.time.get.members/get_date.pass.cpp
index 3f95fd3b4cb..1a1dae754f0 100644
--- a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/locale.time.get.members/get_date.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/locale.time.get.members/get_date.pass.cpp
@@ -30,7 +30,7 @@ public:
         : F(refs) {}
 };
 
-int main()
+int main(int, char**)
 {
     const my_facet f(1);
     std::ios ios(0);
@@ -47,4 +47,6 @@ int main()
         assert(t.tm_year == 105);
         assert(err == std::ios_base::eofbit);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/locale.time.get.members/get_date_wide.pass.cpp b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/locale.time.get.members/get_date_wide.pass.cpp
index e7f19a5dad2..1fe184bea2f 100644
--- a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/locale.time.get.members/get_date_wide.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/locale.time.get.members/get_date_wide.pass.cpp
@@ -30,7 +30,7 @@ public:
         : F(refs) {}
 };
 
-int main()
+int main(int, char**)
 {
     const my_facet f(1);
     std::ios ios(0);
@@ -47,4 +47,6 @@ int main()
         assert(t.tm_year == 105);
         assert(err == std::ios_base::eofbit);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/locale.time.get.members/get_many.pass.cpp b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/locale.time.get.members/get_many.pass.cpp
index 22b2825c865..2416f6275d7 100644
--- a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/locale.time.get.members/get_many.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/locale.time.get.members/get_many.pass.cpp
@@ -30,7 +30,7 @@ public:
         : F(refs) {}
 };
 
-int main()
+int main(int, char**)
 {
     const my_facet f(1);
     std::ios ios(0);
@@ -64,4 +64,6 @@ int main()
         assert(t.tm_min == 27);
         assert(err == std::ios_base::eofbit);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/locale.time.get.members/get_monthname.pass.cpp b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/locale.time.get.members/get_monthname.pass.cpp
index e7b86c79106..8e61dcca876 100644
--- a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/locale.time.get.members/get_monthname.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/locale.time.get.members/get_monthname.pass.cpp
@@ -30,7 +30,7 @@ public:
         : F(refs) {}
 };
 
-int main()
+int main(int, char**)
 {
     const my_facet f(1);
     std::ios ios(0);
@@ -261,4 +261,6 @@ int main()
         assert(t.tm_mon == 0);
         assert(err == std::ios_base::failbit);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/locale.time.get.members/get_monthname_wide.pass.cpp b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/locale.time.get.members/get_monthname_wide.pass.cpp
index 78d32ece4f1..a8eb4864ecb 100644
--- a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/locale.time.get.members/get_monthname_wide.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/locale.time.get.members/get_monthname_wide.pass.cpp
@@ -30,7 +30,7 @@ public:
         : F(refs) {}
 };
 
-int main()
+int main(int, char**)
 {
     const my_facet f(1);
     std::ios ios(0);
@@ -261,4 +261,6 @@ int main()
         assert(t.tm_mon == 0);
         assert(err == std::ios_base::failbit);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/locale.time.get.members/get_one.pass.cpp b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/locale.time.get.members/get_one.pass.cpp
index fb8b4980817..0c6d9085b57 100644
--- a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/locale.time.get.members/get_one.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/locale.time.get.members/get_one.pass.cpp
@@ -29,7 +29,7 @@ public:
         : F(refs) {}
 };
 
-int main()
+int main(int, char**)
 {
     const my_facet f(1);
     std::ios ios(0);
@@ -301,4 +301,6 @@ int main()
         assert(i.base() == in+sizeof(in)-1);
         assert(err == std::ios_base::eofbit);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/locale.time.get.members/get_time.pass.cpp b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/locale.time.get.members/get_time.pass.cpp
index c2523dc5d2e..ca0227973dd 100644
--- a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/locale.time.get.members/get_time.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/locale.time.get.members/get_time.pass.cpp
@@ -30,7 +30,7 @@ public:
         : F(refs) {}
 };
 
-int main()
+int main(int, char**)
 {
     const my_facet f(1);
     std::ios ios(0);
@@ -113,4 +113,6 @@ int main()
 //         assert(t.tm_sec == 0);
         assert(err == std::ios_base::failbit);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/locale.time.get.members/get_time_wide.pass.cpp b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/locale.time.get.members/get_time_wide.pass.cpp
index f78359c918b..98f2a8570ef 100644
--- a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/locale.time.get.members/get_time_wide.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/locale.time.get.members/get_time_wide.pass.cpp
@@ -30,7 +30,7 @@ public:
         : F(refs) {}
 };
 
-int main()
+int main(int, char**)
 {
     const my_facet f(1);
     std::ios ios(0);
@@ -113,4 +113,6 @@ int main()
 //         assert(t.tm_sec == 0);
         assert(err == std::ios_base::failbit);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/locale.time.get.members/get_weekday.pass.cpp b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/locale.time.get.members/get_weekday.pass.cpp
index f972a63bf20..16e853a4991 100644
--- a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/locale.time.get.members/get_weekday.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/locale.time.get.members/get_weekday.pass.cpp
@@ -30,7 +30,7 @@ public:
         : F(refs) {}
 };
 
-int main()
+int main(int, char**)
 {
     const my_facet f(1);
     std::ios ios(0);
@@ -216,4 +216,6 @@ int main()
         assert(t.tm_wday == 6);
         assert(err == std::ios_base::eofbit);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/locale.time.get.members/get_weekday_wide.pass.cpp b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/locale.time.get.members/get_weekday_wide.pass.cpp
index 3e6e982bd8a..3b7b4e9d83b 100644
--- a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/locale.time.get.members/get_weekday_wide.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/locale.time.get.members/get_weekday_wide.pass.cpp
@@ -30,7 +30,7 @@ public:
         : F(refs) {}
 };
 
-int main()
+int main(int, char**)
 {
     const my_facet f(1);
     std::ios ios(0);
@@ -216,4 +216,6 @@ int main()
         assert(t.tm_wday == 6);
         assert(err == std::ios_base::eofbit);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/locale.time.get.members/get_year.pass.cpp b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/locale.time.get.members/get_year.pass.cpp
index 210112f8e30..8a0b8405914 100644
--- a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/locale.time.get.members/get_year.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/locale.time.get.members/get_year.pass.cpp
@@ -29,7 +29,7 @@ public:
         : F(refs) {}
 };
 
-int main()
+int main(int, char**)
 {
     const my_facet f(1);
     std::ios ios(0);
@@ -134,4 +134,6 @@ int main()
         assert(t.tm_year == 1099);
         assert(err == std::ios_base::goodbit);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/locale.time.get.virtuals/tested_elsewhere.pass.cpp b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/locale.time.get.virtuals/tested_elsewhere.pass.cpp
index f77636c8475..1f764da05d6 100644
--- a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/locale.time.get.virtuals/tested_elsewhere.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/locale.time.get.virtuals/tested_elsewhere.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/time_base.pass.cpp b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/time_base.pass.cpp
index c046a7de6ce..c1b509b40d5 100644
--- a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/time_base.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/time_base.pass.cpp
@@ -17,7 +17,7 @@
 #include <locale>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::time_base::dateorder d = std::time_base::no_order;
     ((void)d); // Prevent unused warning
@@ -26,4 +26,6 @@ int main()
     assert(std::time_base::mdy == 2);
     assert(std::time_base::ymd == 3);
     assert(std::time_base::ydm == 4);
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/types.pass.cpp b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/types.pass.cpp
index ba0dd69e452..bd74f7da8e6 100644
--- a/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/types.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.time/locale.time.get/types.pass.cpp
@@ -27,7 +27,7 @@
 #include <iterator>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_base_of<std::locale::facet, std::time_get<char> >::value), "");
     static_assert((std::is_base_of<std::locale::facet, std::time_get<wchar_t> >::value), "");
@@ -37,4 +37,6 @@ int main()
     static_assert((std::is_same<std::time_get<wchar_t>::char_type, wchar_t>::value), "");
     static_assert((std::is_same<std::time_get<char>::iter_type, std::istreambuf_iterator<char> >::value), "");
     static_assert((std::is_same<std::time_get<wchar_t>::iter_type, std::istreambuf_iterator<wchar_t> >::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.time/locale.time.put.byname/put1.pass.cpp b/libcxx/test/std/localization/locale.categories/category.time/locale.time.put.byname/put1.pass.cpp
index 30f1eef6e8f..cd70133274e 100644
--- a/libcxx/test/std/localization/locale.categories/category.time/locale.time.put.byname/put1.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.time/locale.time.put.byname/put1.pass.cpp
@@ -45,7 +45,7 @@ public:
         : F(nm, refs) {}
 };
 
-int main()
+int main(int, char**)
 {
     char str[200];
     output_iterator<char*> iter;
@@ -77,4 +77,6 @@ int main()
         assert((ex == "Today is Samedi which is abbreviated Sam.")||
                (ex == "Today is samedi which is abbreviated sam." ));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.time/locale.time.put/ctor.pass.cpp b/libcxx/test/std/localization/locale.categories/category.time/locale.time.put/ctor.pass.cpp
index 2010ef4ffd8..9d0ec1ad718 100644
--- a/libcxx/test/std/localization/locale.categories/category.time/locale.time.put/ctor.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.time/locale.time.put/ctor.pass.cpp
@@ -31,7 +31,7 @@ public:
 
 int my_facet::count = 0;
 
-int main()
+int main(int, char**)
 {
     {
         std::locale l(std::locale::classic(), new my_facet);
@@ -48,4 +48,6 @@ int main()
         assert(my_facet::count == 1);
     }
     assert(my_facet::count == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.time/locale.time.put/locale.time.put.members/put1.pass.cpp b/libcxx/test/std/localization/locale.categories/category.time/locale.time.put/locale.time.put.members/put1.pass.cpp
index 24971f48f7c..94faa80f1ef 100644
--- a/libcxx/test/std/localization/locale.categories/category.time/locale.time.put/locale.time.put.members/put1.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.time/locale.time.put/locale.time.put.members/put1.pass.cpp
@@ -27,7 +27,7 @@ public:
         : F(refs) {}
 };
 
-int main()
+int main(int, char**)
 {
     const my_facet f(1);
     char str[200];
@@ -57,4 +57,6 @@ int main()
         std::string ex(str, iter.base());
         assert(ex == "The number of the month is 05.");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.time/locale.time.put/locale.time.put.members/put2.pass.cpp b/libcxx/test/std/localization/locale.categories/category.time/locale.time.put/locale.time.put.members/put2.pass.cpp
index 9bef3e787c4..a3b6cf5b25c 100644
--- a/libcxx/test/std/localization/locale.categories/category.time/locale.time.put/locale.time.put.members/put2.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.time/locale.time.put/locale.time.put.members/put2.pass.cpp
@@ -27,7 +27,7 @@ public:
         : F(refs) {}
 };
 
-int main()
+int main(int, char**)
 {
     const my_facet f(1);
     char str[200];
@@ -328,4 +328,6 @@ int main()
         std::string ex(str, iter.base());
         assert(ex == "%");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.time/locale.time.put/locale.time.put.virtuals/tested_elsewhere.pass.cpp b/libcxx/test/std/localization/locale.categories/category.time/locale.time.put/locale.time.put.virtuals/tested_elsewhere.pass.cpp
index f77636c8475..1f764da05d6 100644
--- a/libcxx/test/std/localization/locale.categories/category.time/locale.time.put/locale.time.put.virtuals/tested_elsewhere.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.time/locale.time.put/locale.time.put.virtuals/tested_elsewhere.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.time/locale.time.put/types.pass.cpp b/libcxx/test/std/localization/locale.categories/category.time/locale.time.put/types.pass.cpp
index c638624d0bb..4361094f4b0 100644
--- a/libcxx/test/std/localization/locale.categories/category.time/locale.time.put/types.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.time/locale.time.put/types.pass.cpp
@@ -20,7 +20,7 @@
 #include <iterator>
 #include <type_traits>
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_base_of<std::locale::facet, std::time_put<char> >::value), "");
     static_assert((std::is_base_of<std::locale::facet, std::time_put<wchar_t> >::value), "");
@@ -28,4 +28,6 @@ int main()
     static_assert((std::is_same<std::time_put<wchar_t>::char_type, wchar_t>::value), "");
     static_assert((std::is_same<std::time_put<char>::iter_type, std::ostreambuf_iterator<char> >::value), "");
     static_assert((std::is_same<std::time_put<wchar_t>::iter_type, std::ostreambuf_iterator<wchar_t> >::value), "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/category.time/nothing_to_do.pass.cpp b/libcxx/test/std/localization/locale.categories/category.time/nothing_to_do.pass.cpp
index f77636c8475..1f764da05d6 100644
--- a/libcxx/test/std/localization/locale.categories/category.time/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/category.time/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/facet.numpunct/locale.numpunct.byname/decimal_point.pass.cpp b/libcxx/test/std/localization/locale.categories/facet.numpunct/locale.numpunct.byname/decimal_point.pass.cpp
index cddc1497e90..f8132872d4c 100644
--- a/libcxx/test/std/localization/locale.categories/facet.numpunct/locale.numpunct.byname/decimal_point.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/facet.numpunct/locale.numpunct.byname/decimal_point.pass.cpp
@@ -20,7 +20,7 @@
 
 #include "platform_support.h" // locale name macros
 
-int main()
+int main(int, char**)
 {
     {
         std::locale l("C");
@@ -61,4 +61,6 @@ int main()
             assert(np.decimal_point() == L',');
         }
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/facet.numpunct/locale.numpunct.byname/grouping.pass.cpp b/libcxx/test/std/localization/locale.categories/facet.numpunct/locale.numpunct.byname/grouping.pass.cpp
index c6e67dbfb27..4dbc7e7b8f2 100644
--- a/libcxx/test/std/localization/locale.categories/facet.numpunct/locale.numpunct.byname/grouping.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/facet.numpunct/locale.numpunct.byname/grouping.pass.cpp
@@ -24,7 +24,7 @@
 #include "test_macros.h"
 #include "platform_support.h" // locale name macros
 
-int main()
+int main(int, char**)
 {
     {
         std::locale l("C");
@@ -70,4 +70,6 @@ int main()
             assert(np.grouping() == group);
         }
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/facet.numpunct/locale.numpunct.byname/thousands_sep.pass.cpp b/libcxx/test/std/localization/locale.categories/facet.numpunct/locale.numpunct.byname/thousands_sep.pass.cpp
index 7d6978a9362..25690024027 100644
--- a/libcxx/test/std/localization/locale.categories/facet.numpunct/locale.numpunct.byname/thousands_sep.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/facet.numpunct/locale.numpunct.byname/thousands_sep.pass.cpp
@@ -26,7 +26,7 @@
 #include "test_macros.h"
 #include "platform_support.h" // locale name macros
 
-int main()
+int main(int, char**)
 {
     {
         std::locale l("C");
@@ -84,4 +84,6 @@ int main()
             assert(np.thousands_sep() == wsep);
         }
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/facet.numpunct/locale.numpunct/ctor.pass.cpp b/libcxx/test/std/localization/locale.categories/facet.numpunct/locale.numpunct/ctor.pass.cpp
index 39d0de2775f..e3a10a5c3a3 100644
--- a/libcxx/test/std/localization/locale.categories/facet.numpunct/locale.numpunct/ctor.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/facet.numpunct/locale.numpunct/ctor.pass.cpp
@@ -30,7 +30,7 @@ public:
 
 template <class C> int my_facet<C>::count = 0;
 
-int main()
+int main(int, char**)
 {
     {
         std::locale l(std::locale::classic(), new my_facet<char>);
@@ -62,4 +62,6 @@ int main()
         assert(my_facet<wchar_t>::count == 1);
     }
     assert(my_facet<wchar_t>::count == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/facet.numpunct/locale.numpunct/facet.numpunct.members/decimal_point.pass.cpp b/libcxx/test/std/localization/locale.categories/facet.numpunct/locale.numpunct/facet.numpunct.members/decimal_point.pass.cpp
index 43385c023e8..5322c8a87f1 100644
--- a/libcxx/test/std/localization/locale.categories/facet.numpunct/locale.numpunct/facet.numpunct.members/decimal_point.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/facet.numpunct/locale.numpunct/facet.numpunct.members/decimal_point.pass.cpp
@@ -15,7 +15,7 @@
 #include <locale>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     {
@@ -28,4 +28,6 @@ int main()
         const std::numpunct<C>& np = std::use_facet<std::numpunct<C> >(l);
         assert(np.decimal_point() == L'.');
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/facet.numpunct/locale.numpunct/facet.numpunct.members/falsename.pass.cpp b/libcxx/test/std/localization/locale.categories/facet.numpunct/locale.numpunct/facet.numpunct.members/falsename.pass.cpp
index 7cbf9b43a0d..d1f20f3bbdb 100644
--- a/libcxx/test/std/localization/locale.categories/facet.numpunct/locale.numpunct/facet.numpunct.members/falsename.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/facet.numpunct/locale.numpunct/facet.numpunct.members/falsename.pass.cpp
@@ -15,7 +15,7 @@
 #include <locale>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     {
@@ -28,4 +28,6 @@ int main()
         const std::numpunct<C>& np = std::use_facet<std::numpunct<C> >(l);
         assert(np.falsename() == std::wstring(L"false"));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/facet.numpunct/locale.numpunct/facet.numpunct.members/grouping.pass.cpp b/libcxx/test/std/localization/locale.categories/facet.numpunct/locale.numpunct/facet.numpunct.members/grouping.pass.cpp
index 2ce956df73d..4c23c51acde 100644
--- a/libcxx/test/std/localization/locale.categories/facet.numpunct/locale.numpunct/facet.numpunct.members/grouping.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/facet.numpunct/locale.numpunct/facet.numpunct.members/grouping.pass.cpp
@@ -15,7 +15,7 @@
 #include <locale>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     {
@@ -28,4 +28,6 @@ int main()
         const std::numpunct<C>& np = std::use_facet<std::numpunct<C> >(l);
         assert(np.grouping() == std::string());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/facet.numpunct/locale.numpunct/facet.numpunct.members/thousands_sep.pass.cpp b/libcxx/test/std/localization/locale.categories/facet.numpunct/locale.numpunct/facet.numpunct.members/thousands_sep.pass.cpp
index cc47edbf23c..2044c98a1df 100644
--- a/libcxx/test/std/localization/locale.categories/facet.numpunct/locale.numpunct/facet.numpunct.members/thousands_sep.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/facet.numpunct/locale.numpunct/facet.numpunct.members/thousands_sep.pass.cpp
@@ -15,7 +15,7 @@
 #include <locale>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     {
@@ -28,4 +28,6 @@ int main()
         const std::numpunct<C>& np = std::use_facet<std::numpunct<C> >(l);
         assert(np.thousands_sep() == L',');
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/facet.numpunct/locale.numpunct/facet.numpunct.members/truename.pass.cpp b/libcxx/test/std/localization/locale.categories/facet.numpunct/locale.numpunct/facet.numpunct.members/truename.pass.cpp
index 96fb3011d63..359c96bef4e 100644
--- a/libcxx/test/std/localization/locale.categories/facet.numpunct/locale.numpunct/facet.numpunct.members/truename.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/facet.numpunct/locale.numpunct/facet.numpunct.members/truename.pass.cpp
@@ -15,7 +15,7 @@
 #include <locale>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     {
@@ -28,4 +28,6 @@ int main()
         const std::numpunct<C>& np = std::use_facet<std::numpunct<C> >(l);
         assert(np.truename() == std::wstring(L"true"));
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/facet.numpunct/locale.numpunct/facet.numpunct.virtuals/tested_elsewhere.pass.cpp b/libcxx/test/std/localization/locale.categories/facet.numpunct/locale.numpunct/facet.numpunct.virtuals/tested_elsewhere.pass.cpp
index f77636c8475..1f764da05d6 100644
--- a/libcxx/test/std/localization/locale.categories/facet.numpunct/locale.numpunct/facet.numpunct.virtuals/tested_elsewhere.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/facet.numpunct/locale.numpunct/facet.numpunct.virtuals/tested_elsewhere.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/facet.numpunct/locale.numpunct/types.pass.cpp b/libcxx/test/std/localization/locale.categories/facet.numpunct/locale.numpunct/types.pass.cpp
index 236d9460d34..212670af402 100644
--- a/libcxx/test/std/localization/locale.categories/facet.numpunct/locale.numpunct/types.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/facet.numpunct/locale.numpunct/types.pass.cpp
@@ -21,7 +21,7 @@
 #include <type_traits>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::locale l = std::locale::classic();
     {
@@ -46,4 +46,6 @@ int main()
         static_assert((std::is_same<std::numpunct<wchar_t>::string_type, std::wstring>::value), "");
         static_assert((std::is_base_of<std::locale::facet, std::numpunct<wchar_t> >::value), "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/facet.numpunct/nothing_to_do.pass.cpp b/libcxx/test/std/localization/locale.categories/facet.numpunct/nothing_to_do.pass.cpp
index f77636c8475..1f764da05d6 100644
--- a/libcxx/test/std/localization/locale.categories/facet.numpunct/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/facet.numpunct/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.categories/facets.examples/nothing_to_do.pass.cpp b/libcxx/test/std/localization/locale.categories/facets.examples/nothing_to_do.pass.cpp
index f77636c8475..1f764da05d6 100644
--- a/libcxx/test/std/localization/locale.categories/facets.examples/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/localization/locale.categories/facets.examples/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.stdcvt/codecvt_mode.pass.cpp b/libcxx/test/std/localization/locale.stdcvt/codecvt_mode.pass.cpp
index 160594850d4..def721c4aac 100644
--- a/libcxx/test/std/localization/locale.stdcvt/codecvt_mode.pass.cpp
+++ b/libcxx/test/std/localization/locale.stdcvt/codecvt_mode.pass.cpp
@@ -18,11 +18,13 @@
 #include <codecvt>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     assert(std::consume_header == 4);
     assert(std::generate_header == 2);
     assert(std::little_endian == 1);
     std::codecvt_mode e = std::consume_header;
     assert(e == 4);
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.stdcvt/codecvt_utf16.pass.cpp b/libcxx/test/std/localization/locale.stdcvt/codecvt_utf16.pass.cpp
index 22be9593bd2..a66129610fe 100644
--- a/libcxx/test/std/localization/locale.stdcvt/codecvt_utf16.pass.cpp
+++ b/libcxx/test/std/localization/locale.stdcvt/codecvt_utf16.pass.cpp
@@ -24,7 +24,7 @@
 
 #include "count_new.hpp"
 
-int main()
+int main(int, char**)
 {
     assert(globalMemCounter.checkOutstandingNewEq(0));
     {
@@ -38,4 +38,6 @@ int main()
         assert(globalMemCounter.checkOutstandingNewNotEq(0));
     }
     assert(globalMemCounter.checkOutstandingNewEq(0));
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.stdcvt/codecvt_utf16_always_noconv.pass.cpp b/libcxx/test/std/localization/locale.stdcvt/codecvt_utf16_always_noconv.pass.cpp
index 91d95af9a04..6bd37789d30 100644
--- a/libcxx/test/std/localization/locale.stdcvt/codecvt_utf16_always_noconv.pass.cpp
+++ b/libcxx/test/std/localization/locale.stdcvt/codecvt_utf16_always_noconv.pass.cpp
@@ -21,7 +21,7 @@
 #include <codecvt>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::codecvt_utf16<wchar_t> C;
@@ -41,4 +41,6 @@ int main()
         bool r = c.always_noconv();
         assert(r == false);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.stdcvt/codecvt_utf16_encoding.pass.cpp b/libcxx/test/std/localization/locale.stdcvt/codecvt_utf16_encoding.pass.cpp
index d3fbea6dc2e..2e8a1833c78 100644
--- a/libcxx/test/std/localization/locale.stdcvt/codecvt_utf16_encoding.pass.cpp
+++ b/libcxx/test/std/localization/locale.stdcvt/codecvt_utf16_encoding.pass.cpp
@@ -21,7 +21,7 @@
 #include <codecvt>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::codecvt_utf16<wchar_t> C;
@@ -41,4 +41,6 @@ int main()
         int r = c.encoding();
         assert(r == 0);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.stdcvt/codecvt_utf16_in.pass.cpp b/libcxx/test/std/localization/locale.stdcvt/codecvt_utf16_in.pass.cpp
index e44783564c1..4ccf933d601 100644
--- a/libcxx/test/std/localization/locale.stdcvt/codecvt_utf16_in.pass.cpp
+++ b/libcxx/test/std/localization/locale.stdcvt/codecvt_utf16_in.pass.cpp
@@ -24,7 +24,7 @@
 #include <codecvt>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::codecvt_utf16<char32_t> C;
@@ -735,4 +735,6 @@ int main()
         assert(np == n+2);
         assert(w == 0x56);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.stdcvt/codecvt_utf16_length.pass.cpp b/libcxx/test/std/localization/locale.stdcvt/codecvt_utf16_length.pass.cpp
index 4e6fdf85849..39ecb8f0ea0 100644
--- a/libcxx/test/std/localization/locale.stdcvt/codecvt_utf16_length.pass.cpp
+++ b/libcxx/test/std/localization/locale.stdcvt/codecvt_utf16_length.pass.cpp
@@ -22,7 +22,7 @@
 #include <codecvt>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::codecvt_utf16<wchar_t> C;
@@ -445,4 +445,6 @@ int main()
         r = c.length(m, n, n+2, 2);
         assert(r == 2);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.stdcvt/codecvt_utf16_max_length.pass.cpp b/libcxx/test/std/localization/locale.stdcvt/codecvt_utf16_max_length.pass.cpp
index 6422d56797b..fa8c3269ad4 100644
--- a/libcxx/test/std/localization/locale.stdcvt/codecvt_utf16_max_length.pass.cpp
+++ b/libcxx/test/std/localization/locale.stdcvt/codecvt_utf16_max_length.pass.cpp
@@ -21,7 +21,7 @@
 #include <codecvt>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::codecvt_utf16<wchar_t> C;
@@ -59,4 +59,6 @@ int main()
         int r = c.max_length();
         assert(r == 6);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.stdcvt/codecvt_utf16_out.pass.cpp b/libcxx/test/std/localization/locale.stdcvt/codecvt_utf16_out.pass.cpp
index afd1e6ad661..beabf842ec3 100644
--- a/libcxx/test/std/localization/locale.stdcvt/codecvt_utf16_out.pass.cpp
+++ b/libcxx/test/std/localization/locale.stdcvt/codecvt_utf16_out.pass.cpp
@@ -346,7 +346,9 @@ void TestHelper<CharT, 4>::test() {
   }
 }
 
-int main() {
+int main(int, char**) {
   TestHelper<char32_t>::test();
   TestHelper<wchar_t>::test();
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.stdcvt/codecvt_utf16_unshift.pass.cpp b/libcxx/test/std/localization/locale.stdcvt/codecvt_utf16_unshift.pass.cpp
index 2471ccb1952..2c37e257815 100644
--- a/libcxx/test/std/localization/locale.stdcvt/codecvt_utf16_unshift.pass.cpp
+++ b/libcxx/test/std/localization/locale.stdcvt/codecvt_utf16_unshift.pass.cpp
@@ -23,7 +23,7 @@
 #include <codecvt>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::codecvt_utf16<wchar_t> C;
@@ -52,4 +52,6 @@ int main()
         std::codecvt_base::result r = c.unshift(m, n, n+4, np);
         assert(r == std::codecvt_base::noconv);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8.pass.cpp b/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8.pass.cpp
index f350b62ca6b..450f5250929 100644
--- a/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8.pass.cpp
+++ b/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8.pass.cpp
@@ -24,7 +24,7 @@
 
 #include "count_new.hpp"
 
-int main()
+int main(int, char**)
 {
     assert(globalMemCounter.checkOutstandingNewEq(0));
     {
@@ -38,4 +38,6 @@ int main()
         assert(globalMemCounter.checkOutstandingNewNotEq(0));
     }
     assert(globalMemCounter.checkOutstandingNewEq(0));
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8_always_noconv.pass.cpp b/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8_always_noconv.pass.cpp
index 167521573bd..7d7ba19be8d 100644
--- a/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8_always_noconv.pass.cpp
+++ b/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8_always_noconv.pass.cpp
@@ -21,7 +21,7 @@
 #include <codecvt>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::codecvt_utf8<wchar_t> C;
@@ -41,4 +41,6 @@ int main()
         bool r = c.always_noconv();
         assert(r == false);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8_encoding.pass.cpp b/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8_encoding.pass.cpp
index 324546d9936..d8e689f6235 100644
--- a/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8_encoding.pass.cpp
+++ b/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8_encoding.pass.cpp
@@ -21,7 +21,7 @@
 #include <codecvt>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::codecvt_utf8<wchar_t> C;
@@ -41,4 +41,6 @@ int main()
         int r = c.encoding();
         assert(r == 0);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8_in.pass.cpp b/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8_in.pass.cpp
index 4f5d3d8fbee..611d06305c9 100644
--- a/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8_in.pass.cpp
+++ b/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8_in.pass.cpp
@@ -24,7 +24,7 @@
 #include <codecvt>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::codecvt_utf8<char32_t> C;
@@ -356,4 +356,6 @@ int main()
         assert(np == n+1);
         assert(w == 0x56);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8_length.pass.cpp b/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8_length.pass.cpp
index 4b5e096afa9..2df1c96035c 100644
--- a/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8_length.pass.cpp
+++ b/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8_length.pass.cpp
@@ -22,7 +22,7 @@
 #include <codecvt>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::codecvt_utf8<wchar_t> C;
@@ -240,4 +240,6 @@ int main()
         r = c.length(m, n, n+1, 3);
         assert(r == 1);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8_max_length.pass.cpp b/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8_max_length.pass.cpp
index a353ad6cf56..57e5f5850c6 100644
--- a/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8_max_length.pass.cpp
+++ b/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8_max_length.pass.cpp
@@ -21,7 +21,7 @@
 #include <codecvt>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::codecvt_utf8<wchar_t> C;
@@ -59,4 +59,6 @@ int main()
         int r = c.max_length();
         assert(r == 7);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8_out.pass.cpp b/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8_out.pass.cpp
index 430b5c2548c..f8b56bcb6cf 100644
--- a/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8_out.pass.cpp
+++ b/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8_out.pass.cpp
@@ -318,8 +318,10 @@ void TestHelper<CharT, 4>::test() {
   }
 }
 
-int main() {
+int main(int, char**) {
   TestHelper<wchar_t>::test();
   TestHelper<char32_t>::test();
   TestHelper<char16_t>::test();
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8_unshift.pass.cpp b/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8_unshift.pass.cpp
index 344b3e503cc..a41f997977f 100644
--- a/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8_unshift.pass.cpp
+++ b/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8_unshift.pass.cpp
@@ -23,7 +23,7 @@
 #include <codecvt>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::codecvt_utf8<wchar_t> C;
@@ -52,4 +52,6 @@ int main()
         std::codecvt_base::result r = c.unshift(m, n, n+4, np);
         assert(r == std::codecvt_base::noconv);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8_utf16_always_noconv.pass.cpp b/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8_utf16_always_noconv.pass.cpp
index 6d658624e09..c7fe09caf13 100644
--- a/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8_utf16_always_noconv.pass.cpp
+++ b/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8_utf16_always_noconv.pass.cpp
@@ -21,7 +21,7 @@
 #include <codecvt>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::codecvt_utf8_utf16<wchar_t> C;
@@ -41,4 +41,6 @@ int main()
         bool r = c.always_noconv();
         assert(r == false);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8_utf16_encoding.pass.cpp b/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8_utf16_encoding.pass.cpp
index a392c8a25b6..595f7888e1c 100644
--- a/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8_utf16_encoding.pass.cpp
+++ b/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8_utf16_encoding.pass.cpp
@@ -21,7 +21,7 @@
 #include <codecvt>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::codecvt_utf8_utf16<wchar_t> C;
@@ -41,4 +41,6 @@ int main()
         int r = c.encoding();
         assert(r == 0);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8_utf16_in.pass.cpp b/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8_utf16_in.pass.cpp
index aab52fdf12e..482521032af 100644
--- a/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8_utf16_in.pass.cpp
+++ b/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8_utf16_in.pass.cpp
@@ -234,10 +234,12 @@ void TestHelper<CharT, 4>::test() {
   }
 }
 
-int main() {
+int main(int, char**) {
 #ifndef _WIN32
   TestHelper<wchar_t>::test();
 #endif
   TestHelper<char32_t>::test();
   TestHelper<char16_t>::test();
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8_utf16_length.pass.cpp b/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8_utf16_length.pass.cpp
index 172a8734de6..33a4b5f04bd 100644
--- a/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8_utf16_length.pass.cpp
+++ b/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8_utf16_length.pass.cpp
@@ -22,7 +22,7 @@
 #include <codecvt>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::codecvt_utf8_utf16<wchar_t> C;
@@ -231,4 +231,6 @@ int main()
         r = c.length(m, n, n+1, 2);
         assert(r == 1);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8_utf16_max_length.pass.cpp b/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8_utf16_max_length.pass.cpp
index 247e0ce207a..5d93d929e56 100644
--- a/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8_utf16_max_length.pass.cpp
+++ b/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8_utf16_max_length.pass.cpp
@@ -21,7 +21,7 @@
 #include <codecvt>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::codecvt_utf8_utf16<wchar_t> C;
@@ -59,4 +59,6 @@ int main()
         int r = c.max_length();
         assert(r == 7);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8_utf16_out.pass.cpp b/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8_utf16_out.pass.cpp
index 846df215671..89908eb7756 100644
--- a/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8_utf16_out.pass.cpp
+++ b/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8_utf16_out.pass.cpp
@@ -299,10 +299,12 @@ void TestHelper<CharT, 4>::test() {
   }
 }
 
-int main() {
+int main(int, char**) {
 #ifndef _WIN32
   TestHelper<wchar_t>::test();
 #endif
   TestHelper<char32_t>::test();
   TestHelper<char16_t>::test();
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8_utf16_unshift.pass.cpp b/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8_utf16_unshift.pass.cpp
index 96139bd5b6b..79b670055d5 100644
--- a/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8_utf16_unshift.pass.cpp
+++ b/libcxx/test/std/localization/locale.stdcvt/codecvt_utf8_utf16_unshift.pass.cpp
@@ -23,7 +23,7 @@
 #include <codecvt>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::codecvt_utf8_utf16<wchar_t> C;
@@ -52,4 +52,6 @@ int main()
         std::codecvt_base::result r = c.unshift(m, n, n+4, np);
         assert(r == std::codecvt_base::noconv);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locale.syn/nothing_to_do.pass.cpp b/libcxx/test/std/localization/locale.syn/nothing_to_do.pass.cpp
index f77636c8475..1f764da05d6 100644
--- a/libcxx/test/std/localization/locale.syn/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/localization/locale.syn/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locales/locale.convenience/classification/isalnum.pass.cpp b/libcxx/test/std/localization/locales/locale.convenience/classification/isalnum.pass.cpp
index 68b9b9f1b73..2cf9e4b5749 100644
--- a/libcxx/test/std/localization/locales/locale.convenience/classification/isalnum.pass.cpp
+++ b/libcxx/test/std/localization/locales/locale.convenience/classification/isalnum.pass.cpp
@@ -13,7 +13,7 @@
 #include <locale>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::locale l;
     assert(!std::isalnum(' ', l));
@@ -27,4 +27,6 @@ int main()
     assert( std::isalnum('f', l));
     assert( std::isalnum('9', l));
     assert(!std::isalnum('+', l));
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locales/locale.convenience/classification/isalpha.pass.cpp b/libcxx/test/std/localization/locales/locale.convenience/classification/isalpha.pass.cpp
index 0e5a777b315..800c26cb918 100644
--- a/libcxx/test/std/localization/locales/locale.convenience/classification/isalpha.pass.cpp
+++ b/libcxx/test/std/localization/locales/locale.convenience/classification/isalpha.pass.cpp
@@ -13,7 +13,7 @@
 #include <locale>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::locale l;
     assert(!std::isalpha(' ', l));
@@ -27,4 +27,6 @@ int main()
     assert( std::isalpha('f', l));
     assert(!std::isalpha('9', l));
     assert(!std::isalpha('+', l));
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locales/locale.convenience/classification/iscntrl.pass.cpp b/libcxx/test/std/localization/locales/locale.convenience/classification/iscntrl.pass.cpp
index afca98b70b9..d5cd4a6b962 100644
--- a/libcxx/test/std/localization/locales/locale.convenience/classification/iscntrl.pass.cpp
+++ b/libcxx/test/std/localization/locales/locale.convenience/classification/iscntrl.pass.cpp
@@ -13,7 +13,7 @@
 #include <locale>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::locale l;
     assert(!std::iscntrl(' ', l));
@@ -27,4 +27,6 @@ int main()
     assert(!std::iscntrl('f', l));
     assert(!std::iscntrl('9', l));
     assert(!std::iscntrl('+', l));
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locales/locale.convenience/classification/isdigit.pass.cpp b/libcxx/test/std/localization/locales/locale.convenience/classification/isdigit.pass.cpp
index 35a4540fdd8..2e71bd394ac 100644
--- a/libcxx/test/std/localization/locales/locale.convenience/classification/isdigit.pass.cpp
+++ b/libcxx/test/std/localization/locales/locale.convenience/classification/isdigit.pass.cpp
@@ -13,7 +13,7 @@
 #include <locale>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::locale l;
     assert(!std::isdigit(' ', l));
@@ -27,4 +27,6 @@ int main()
     assert(!std::isdigit('f', l));
     assert( std::isdigit('9', l));
     assert(!std::isdigit('+', l));
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locales/locale.convenience/classification/isgraph.pass.cpp b/libcxx/test/std/localization/locales/locale.convenience/classification/isgraph.pass.cpp
index 3b4d0c55162..406b7cbf973 100644
--- a/libcxx/test/std/localization/locales/locale.convenience/classification/isgraph.pass.cpp
+++ b/libcxx/test/std/localization/locales/locale.convenience/classification/isgraph.pass.cpp
@@ -13,7 +13,7 @@
 #include <locale>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::locale l;
     assert(!std::isgraph(' ', l));
@@ -27,4 +27,6 @@ int main()
     assert( std::isgraph('f', l));
     assert( std::isgraph('9', l));
     assert( std::isgraph('+', l));
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locales/locale.convenience/classification/islower.pass.cpp b/libcxx/test/std/localization/locales/locale.convenience/classification/islower.pass.cpp
index 057b7022608..2fc9ece026d 100644
--- a/libcxx/test/std/localization/locales/locale.convenience/classification/islower.pass.cpp
+++ b/libcxx/test/std/localization/locales/locale.convenience/classification/islower.pass.cpp
@@ -13,7 +13,7 @@
 #include <locale>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::locale l;
     assert(!std::islower(' ', l));
@@ -27,4 +27,6 @@ int main()
     assert( std::islower('f', l));
     assert(!std::islower('9', l));
     assert(!std::islower('+', l));
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locales/locale.convenience/classification/isprint.pass.cpp b/libcxx/test/std/localization/locales/locale.convenience/classification/isprint.pass.cpp
index 990fc03eb82..36fa16cbc74 100644
--- a/libcxx/test/std/localization/locales/locale.convenience/classification/isprint.pass.cpp
+++ b/libcxx/test/std/localization/locales/locale.convenience/classification/isprint.pass.cpp
@@ -13,7 +13,7 @@
 #include <locale>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::locale l;
     assert( std::isprint(' ', l));
@@ -27,4 +27,6 @@ int main()
     assert( std::isprint('f', l));
     assert( std::isprint('9', l));
     assert( std::isprint('+', l));
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locales/locale.convenience/classification/ispunct.pass.cpp b/libcxx/test/std/localization/locales/locale.convenience/classification/ispunct.pass.cpp
index b9fb94a3c4b..db11337805c 100644
--- a/libcxx/test/std/localization/locales/locale.convenience/classification/ispunct.pass.cpp
+++ b/libcxx/test/std/localization/locales/locale.convenience/classification/ispunct.pass.cpp
@@ -13,7 +13,7 @@
 #include <locale>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::locale l;
     assert(!std::ispunct(' ', l));
@@ -27,4 +27,6 @@ int main()
     assert(!std::ispunct('f', l));
     assert(!std::ispunct('9', l));
     assert( std::ispunct('+', l));
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locales/locale.convenience/classification/isspace.pass.cpp b/libcxx/test/std/localization/locales/locale.convenience/classification/isspace.pass.cpp
index b00ba46e630..62e50d2fc25 100644
--- a/libcxx/test/std/localization/locales/locale.convenience/classification/isspace.pass.cpp
+++ b/libcxx/test/std/localization/locales/locale.convenience/classification/isspace.pass.cpp
@@ -13,7 +13,7 @@
 #include <locale>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::locale l;
     assert( std::isspace(' ', l));
@@ -27,4 +27,6 @@ int main()
     assert(!std::isspace('f', l));
     assert(!std::isspace('9', l));
     assert(!std::isspace('+', l));
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locales/locale.convenience/classification/isupper.pass.cpp b/libcxx/test/std/localization/locales/locale.convenience/classification/isupper.pass.cpp
index c5863beb30e..c986c7cdddc 100644
--- a/libcxx/test/std/localization/locales/locale.convenience/classification/isupper.pass.cpp
+++ b/libcxx/test/std/localization/locales/locale.convenience/classification/isupper.pass.cpp
@@ -13,7 +13,7 @@
 #include <locale>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::locale l;
     assert(!std::isupper(' ', l));
@@ -27,4 +27,6 @@ int main()
     assert(!std::isupper('f', l));
     assert(!std::isupper('9', l));
     assert(!std::isupper('+', l));
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locales/locale.convenience/classification/isxdigit.pass.cpp b/libcxx/test/std/localization/locales/locale.convenience/classification/isxdigit.pass.cpp
index 4a77628db94..245f2ed6033 100644
--- a/libcxx/test/std/localization/locales/locale.convenience/classification/isxdigit.pass.cpp
+++ b/libcxx/test/std/localization/locales/locale.convenience/classification/isxdigit.pass.cpp
@@ -13,7 +13,7 @@
 #include <locale>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::locale l;
     assert(!std::isxdigit(' ', l));
@@ -27,4 +27,6 @@ int main()
     assert( std::isxdigit('f', l));
     assert( std::isxdigit('9', l));
     assert(!std::isxdigit('+', l));
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.buffer/ctor.pass.cpp b/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.buffer/ctor.pass.cpp
index c16755e20ed..f28abb934e0 100644
--- a/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.buffer/ctor.pass.cpp
+++ b/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.buffer/ctor.pass.cpp
@@ -21,7 +21,7 @@
 #include "test_macros.h"
 #include "count_new.hpp"
 
-int main()
+int main(int, char**)
 {
     typedef std::wbuffer_convert<std::codecvt_utf8<wchar_t> > B;
 #if TEST_STD_VER > 11
@@ -55,4 +55,6 @@ int main()
         assert(globalMemCounter.checkOutstandingNewNotEq(0));
     }
     assert(globalMemCounter.checkOutstandingNewEq(0));
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.buffer/overflow.pass.cpp b/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.buffer/overflow.pass.cpp
index 66f95df53c7..7c404288596 100644
--- a/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.buffer/overflow.pass.cpp
+++ b/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.buffer/overflow.pass.cpp
@@ -37,7 +37,7 @@ struct test_buf
     virtual int_type overflow(int_type c = traits_type::eof()) {return base::overflow(c);}
 };
 
-int main()
+int main(int, char**)
 {
     {
         std::ofstream bs("overflow.dat");
@@ -96,4 +96,6 @@ int main()
         assert(f.get() == -1);
     }
     std::remove("overflow.dat");
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.buffer/pbackfail.pass.cpp b/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.buffer/pbackfail.pass.cpp
index f268f9a2198..dc4144b159c 100644
--- a/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.buffer/pbackfail.pass.cpp
+++ b/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.buffer/pbackfail.pass.cpp
@@ -37,7 +37,7 @@ struct test_buf
     virtual int_type pbackfail(int_type c = traits_type::eof()) {return base::pbackfail(c);}
 };
 
-int main()
+int main(int, char**)
 {
     {
         std::ifstream bs("underflow.dat");
@@ -55,4 +55,6 @@ int main()
         assert(f.sbumpc() == L'2');
         assert(f.sgetc() == L'3');
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.buffer/rdbuf.pass.cpp b/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.buffer/rdbuf.pass.cpp
index ffd5a0df7ab..b58d1d8eb7b 100644
--- a/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.buffer/rdbuf.pass.cpp
+++ b/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.buffer/rdbuf.pass.cpp
@@ -17,7 +17,7 @@
 #include <sstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     typedef std::wbuffer_convert<std::codecvt_utf8<wchar_t> > B;
     {
@@ -27,4 +27,6 @@ int main()
         b.rdbuf(s.rdbuf());
         assert(b.rdbuf() == s.rdbuf());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.buffer/seekoff.pass.cpp b/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.buffer/seekoff.pass.cpp
index 4494d56c7c3..b50f10cc171 100644
--- a/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.buffer/seekoff.pass.cpp
+++ b/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.buffer/seekoff.pass.cpp
@@ -31,7 +31,7 @@ public:
     ~test_codecvt() {}
 };
 
-int main()
+int main(int, char**)
 {
     {
         wchar_t buf[10];
@@ -54,4 +54,6 @@ int main()
         assert(f.sgetc() == L'l');
     }
     std::remove("seekoff.dat");
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.buffer/state.pass.cpp b/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.buffer/state.pass.cpp
index 1816ad0c775..0541dbfb93b 100644
--- a/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.buffer/state.pass.cpp
+++ b/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.buffer/state.pass.cpp
@@ -17,7 +17,7 @@
 #include <sstream>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     typedef std::wbuffer_convert<std::codecvt_utf8<wchar_t> > B;
     {
@@ -25,4 +25,6 @@ int main()
         std::mbstate_t s = b.state();
         ((void)s);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.buffer/test.pass.cpp b/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.buffer/test.pass.cpp
index c22fb6a14a7..e309f3eb650 100644
--- a/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.buffer/test.pass.cpp
+++ b/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.buffer/test.pass.cpp
@@ -15,7 +15,7 @@
 #include <codecvt>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         std::ofstream bytestream("myfile.txt");
@@ -32,4 +32,6 @@ int main()
         assert(ws == L"Hello");
     }
     std::remove("myfile.txt");
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.buffer/underflow.pass.cpp b/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.buffer/underflow.pass.cpp
index 523778f237f..6d04935b301 100644
--- a/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.buffer/underflow.pass.cpp
+++ b/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.buffer/underflow.pass.cpp
@@ -37,7 +37,7 @@ struct test_buf
     virtual int_type underflow() {return base::underflow();}
 };
 
-int main()
+int main(int, char**)
 {
     {
         std::ifstream bs("underflow.dat");
@@ -80,4 +80,6 @@ int main()
         assert(f.sbumpc() == 0x4E53);
         assert(f.sbumpc() == test_buf::traits_type::eof());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.character/tolower.pass.cpp b/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.character/tolower.pass.cpp
index 72b939dfb5e..9885dca5357 100644
--- a/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.character/tolower.pass.cpp
+++ b/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.character/tolower.pass.cpp
@@ -13,7 +13,7 @@
 #include <locale>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::locale l;
     assert(std::tolower(' ', l) == ' ');
@@ -27,4 +27,6 @@ int main()
     assert(std::tolower('f', l) == 'f');
     assert(std::tolower('9', l) == '9');
     assert(std::tolower('+', l) == '+');
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.character/toupper.pass.cpp b/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.character/toupper.pass.cpp
index dbd936529ef..34f675b0592 100644
--- a/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.character/toupper.pass.cpp
+++ b/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.character/toupper.pass.cpp
@@ -13,7 +13,7 @@
 #include <locale>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     std::locale l;
     assert(std::toupper(' ', l) == ' ');
@@ -27,4 +27,6 @@ int main()
     assert(std::toupper('f', l) == 'F');
     assert(std::toupper('9', l) == '9');
     assert(std::toupper('+', l) == '+');
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.string/converted.pass.cpp b/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.string/converted.pass.cpp
index b52bbc0bbcb..802aaf65d0f 100644
--- a/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.string/converted.pass.cpp
+++ b/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.string/converted.pass.cpp
@@ -61,4 +61,6 @@ void TestHelper<CharT, 4>::test() {
   }
 }
 
-int main() { TestHelper<wchar_t>::test(); }
+int main(int, char**) { TestHelper<wchar_t>::test(); 
+  return 0;
+}
diff --git a/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.string/ctor_codecvt.pass.cpp b/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.string/ctor_codecvt.pass.cpp
index 578547f8ec2..3efd26fb4ce 100644
--- a/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.string/ctor_codecvt.pass.cpp
+++ b/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.string/ctor_codecvt.pass.cpp
@@ -18,7 +18,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::codecvt_utf8<wchar_t> Codecvt;
@@ -36,4 +36,6 @@ int main()
         static_assert( std::is_constructible<Myconv, Codecvt*>::value, "");
 #endif
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.string/ctor_codecvt_state.pass.cpp b/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.string/ctor_codecvt_state.pass.cpp
index 0e58bc2252e..6e2d5ff5e9c 100644
--- a/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.string/ctor_codecvt_state.pass.cpp
+++ b/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.string/ctor_codecvt_state.pass.cpp
@@ -16,7 +16,7 @@
 #include <codecvt>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::codecvt_utf8<wchar_t> Codecvt;
@@ -24,4 +24,6 @@ int main()
         Myconv myconv(new Codecvt, std::mbstate_t());
         assert(myconv.converted() == 0);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.string/ctor_copy.pass.cpp b/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.string/ctor_copy.pass.cpp
index c1a874dc251..d035c3160eb 100644
--- a/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.string/ctor_copy.pass.cpp
+++ b/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.string/ctor_copy.pass.cpp
@@ -21,10 +21,12 @@
 #include <codecvt>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     typedef std::codecvt_utf8<wchar_t> Codecvt;
     typedef std::wstring_convert<Codecvt> Myconv;
     static_assert(!std::is_copy_constructible<Myconv>::value, "");
     static_assert(!std::is_copy_assignable<Myconv>::value, "");
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.string/ctor_err_string.pass.cpp b/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.string/ctor_err_string.pass.cpp
index 364cfed80c7..e284c13c062 100644
--- a/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.string/ctor_err_string.pass.cpp
+++ b/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.string/ctor_err_string.pass.cpp
@@ -19,7 +19,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
     typedef std::codecvt_utf8<wchar_t> Codecvt;
     typedef std::wstring_convert<Codecvt> Myconv;
@@ -70,4 +70,6 @@ int main()
         std::wstring ws = myconv.from_bytes('\xA5');
         assert(ws == L"wide error");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.string/from_bytes.pass.cpp b/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.string/from_bytes.pass.cpp
index e527f31a1e2..c1a26d05582 100644
--- a/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.string/from_bytes.pass.cpp
+++ b/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.string/from_bytes.pass.cpp
@@ -68,4 +68,6 @@ void TestHelper<CharT, 4>::test() {
   }
 }
 
-int main() { TestHelper<wchar_t>::test(); }
+int main(int, char**) { TestHelper<wchar_t>::test(); 
+  return 0;
+}
diff --git a/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.string/state.pass.cpp b/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.string/state.pass.cpp
index 0fb5b9f342f..a7588dc2522 100644
--- a/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.string/state.pass.cpp
+++ b/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.string/state.pass.cpp
@@ -15,11 +15,13 @@
 #include <locale>
 #include <codecvt>
 
-int main()
+int main(int, char**)
 {
     typedef std::codecvt_utf8<wchar_t> Codecvt;
     typedef std::wstring_convert<Codecvt> Myconv;
     Myconv myconv;
     std::mbstate_t s = myconv.state();
     ((void)s);
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.string/to_bytes.pass.cpp b/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.string/to_bytes.pass.cpp
index 2e4dce8bd72..397ba6494ee 100644
--- a/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.string/to_bytes.pass.cpp
+++ b/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.string/to_bytes.pass.cpp
@@ -68,4 +68,6 @@ void TestHelper<CharT, 4>::test() {
   }
 }
 
-int main() { TestHelper<wchar_t>::test(); }
+int main(int, char**) { TestHelper<wchar_t>::test(); 
+  return 0;
+}
diff --git a/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.string/types.pass.cpp b/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.string/types.pass.cpp
index eb67ecffc11..c2dea9a9067 100644
--- a/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.string/types.pass.cpp
+++ b/libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.string/types.pass.cpp
@@ -22,7 +22,7 @@
 #include <locale>
 #include <codecvt>
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::wstring_convert<std::codecvt_utf8<wchar_t> > myconv;
@@ -31,4 +31,6 @@ int main()
         static_assert((std::is_same<myconv::state_type, std::mbstate_t>::value), "");
         static_assert((std::is_same<myconv::int_type, std::char_traits<wchar_t>::int_type>::value), "");
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locales/locale.convenience/conversions/nothing_to_do.pass.cpp b/libcxx/test/std/localization/locales/locale.convenience/conversions/nothing_to_do.pass.cpp
index f77636c8475..1f764da05d6 100644
--- a/libcxx/test/std/localization/locales/locale.convenience/conversions/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/localization/locales/locale.convenience/conversions/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locales/locale.convenience/nothing_to_do.pass.cpp b/libcxx/test/std/localization/locales/locale.convenience/nothing_to_do.pass.cpp
index f77636c8475..1f764da05d6 100644
--- a/libcxx/test/std/localization/locales/locale.convenience/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/localization/locales/locale.convenience/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locales/locale.global.templates/has_facet.pass.cpp b/libcxx/test/std/localization/locales/locale.global.templates/has_facet.pass.cpp
index a895b1aa107..66539d1eaba 100644
--- a/libcxx/test/std/localization/locales/locale.global.templates/has_facet.pass.cpp
+++ b/libcxx/test/std/localization/locales/locale.global.templates/has_facet.pass.cpp
@@ -21,11 +21,13 @@ struct my_facet
 
 std::locale::id my_facet::id;
 
-int main()
+int main(int, char**)
 {
     std::locale loc;
     assert(std::has_facet<std::ctype<char> >(loc));
     assert(!std::has_facet<my_facet>(loc));
     std::locale loc2(loc, new my_facet);
     assert(std::has_facet<my_facet>(loc2));
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locales/locale.global.templates/use_facet.pass.cpp b/libcxx/test/std/localization/locales/locale.global.templates/use_facet.pass.cpp
index c7f53975d3a..3c2cb604232 100644
--- a/libcxx/test/std/localization/locales/locale.global.templates/use_facet.pass.cpp
+++ b/libcxx/test/std/localization/locales/locale.global.templates/use_facet.pass.cpp
@@ -30,7 +30,7 @@ struct my_facet
 
 std::locale::id my_facet::id;
 
-int main()
+int main(int, char**)
 {
 #ifndef TEST_HAS_NO_EXCEPTIONS
     try
@@ -53,4 +53,6 @@ int main()
         assert(facet_count == 1);
     }
     assert(facet_count == 0);
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locales/locale/locale.cons/assign.pass.cpp b/libcxx/test/std/localization/locales/locale/locale.cons/assign.pass.cpp
index 02b5f109699..369fee4cb19 100644
--- a/libcxx/test/std/localization/locales/locale/locale.cons/assign.pass.cpp
+++ b/libcxx/test/std/localization/locales/locale/locale.cons/assign.pass.cpp
@@ -56,7 +56,7 @@ void check(const std::locale& loc)
     assert((std::has_facet<std::messages<wchar_t> >(loc)));
 }
 
-int main()
+int main(int, char**)
 {
     {
         std::locale loc(LOCALE_ru_RU_UTF_8);
@@ -67,4 +67,6 @@ int main()
         check(loc2);
     }
     assert(globalMemCounter.checkOutstandingNewEq(0));
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locales/locale/locale.cons/char_pointer.pass.cpp b/libcxx/test/std/localization/locales/locale/locale.cons/char_pointer.pass.cpp
index 5424a8b92dd..c324f394c8b 100644
--- a/libcxx/test/std/localization/locales/locale/locale.cons/char_pointer.pass.cpp
+++ b/libcxx/test/std/localization/locales/locale/locale.cons/char_pointer.pass.cpp
@@ -61,7 +61,7 @@ void check(const std::locale& loc)
     assert((std::has_facet<std::messages<wchar_t> >(loc)));
 }
 
-int main()
+int main(int, char**)
 {
     {
         std::locale loc(LOCALE_ru_RU_UTF_8);
@@ -94,4 +94,6 @@ int main()
         std::locale ok("");
     }
     assert(globalMemCounter.checkOutstandingNewEq(0));
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locales/locale/locale.cons/copy.pass.cpp b/libcxx/test/std/localization/locales/locale/locale.cons/copy.pass.cpp
index 885dfea37b7..4f96ab41554 100644
--- a/libcxx/test/std/localization/locales/locale/locale.cons/copy.pass.cpp
+++ b/libcxx/test/std/localization/locales/locale/locale.cons/copy.pass.cpp
@@ -54,7 +54,7 @@ void check(const std::locale& loc)
     assert((std::has_facet<std::messages<wchar_t> >(loc)));
 }
 
-int main()
+int main(int, char**)
 {
     {
         std::locale loc(LOCALE_fr_FR_UTF_8);
@@ -64,4 +64,6 @@ int main()
         check(loc2);
     }
     assert(globalMemCounter.checkOutstandingNewEq(0));
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locales/locale/locale.cons/default.pass.cpp b/libcxx/test/std/localization/locales/locale/locale.cons/default.pass.cpp
index 8f79b184233..5c1e922cbfe 100644
--- a/libcxx/test/std/localization/locales/locale/locale.cons/default.pass.cpp
+++ b/libcxx/test/std/localization/locales/locale/locale.cons/default.pass.cpp
@@ -53,7 +53,7 @@ void check(const std::locale& loc)
     assert((std::has_facet<std::messages<wchar_t> >(loc)));
 }
 
-int main()
+int main(int, char**)
 {
     int ok;
     {
@@ -73,4 +73,6 @@ int main()
         assert(globalMemCounter.checkOutstandingNewEq(ok));
     }
     assert(globalMemCounter.checkOutstandingNewEq(ok));
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locales/locale/locale.cons/locale_char_pointer_cat.pass.cpp b/libcxx/test/std/localization/locales/locale/locale.cons/locale_char_pointer_cat.pass.cpp
index d0ccb8a3405..70f2cb92b79 100644
--- a/libcxx/test/std/localization/locales/locale/locale.cons/locale_char_pointer_cat.pass.cpp
+++ b/libcxx/test/std/localization/locales/locale/locale.cons/locale_char_pointer_cat.pass.cpp
@@ -59,7 +59,7 @@ void check(const std::locale& loc)
     assert((std::has_facet<std::messages<wchar_t> >(loc)));
 }
 
-int main()
+int main(int, char**)
 {
     {
         std::locale loc(LOCALE_ru_RU_UTF_8);
@@ -68,4 +68,6 @@ int main()
         check(loc2);
     }
     assert(globalMemCounter.checkOutstandingNewEq(0));
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locales/locale/locale.cons/locale_facetptr.pass.cpp b/libcxx/test/std/localization/locales/locale/locale.cons/locale_facetptr.pass.cpp
index 498682f2834..35c06ce5040 100644
--- a/libcxx/test/std/localization/locales/locale/locale.cons/locale_facetptr.pass.cpp
+++ b/libcxx/test/std/localization/locales/locale/locale.cons/locale_facetptr.pass.cpp
@@ -65,7 +65,7 @@ struct my_facet
 
 std::locale::id my_facet::id;
 
-int main()
+int main(int, char**)
 {
     {
         std::locale loc(LOCALE_ru_RU_UTF_8);
@@ -85,4 +85,6 @@ int main()
         assert(loc == loc2);
     }
     assert(globalMemCounter.checkOutstandingNewEq(0));
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locales/locale/locale.cons/locale_locale_cat.pass.cpp b/libcxx/test/std/localization/locales/locale/locale.cons/locale_locale_cat.pass.cpp
index 79db6f044ca..ba54e85542e 100644
--- a/libcxx/test/std/localization/locales/locale/locale.cons/locale_locale_cat.pass.cpp
+++ b/libcxx/test/std/localization/locales/locale/locale.cons/locale_locale_cat.pass.cpp
@@ -59,7 +59,7 @@ void check(const std::locale& loc)
     assert((std::has_facet<std::messages<wchar_t> >(loc)));
 }
 
-int main()
+int main(int, char**)
 {
     {
         std::locale loc(LOCALE_ru_RU_UTF_8);
@@ -68,4 +68,6 @@ int main()
         check(loc2);
     }
     assert(globalMemCounter.checkOutstandingNewEq(0));
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locales/locale/locale.cons/locale_string_cat.pass.cpp b/libcxx/test/std/localization/locales/locale/locale.cons/locale_string_cat.pass.cpp
index 5fdde6c67ff..3cb3aadac97 100644
--- a/libcxx/test/std/localization/locales/locale/locale.cons/locale_string_cat.pass.cpp
+++ b/libcxx/test/std/localization/locales/locale/locale.cons/locale_string_cat.pass.cpp
@@ -60,7 +60,7 @@ void check(const std::locale& loc)
     assert((std::has_facet<std::messages<wchar_t> >(loc)));
 }
 
-int main()
+int main(int, char**)
 {
     {
         std::locale loc(LOCALE_ru_RU_UTF_8);
@@ -69,4 +69,6 @@ int main()
         check(loc2);
     }
     assert(globalMemCounter.checkOutstandingNewEq(0));
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locales/locale/locale.cons/string.pass.cpp b/libcxx/test/std/localization/locales/locale/locale.cons/string.pass.cpp
index 449b9fbc2d1..55b2f88c2be 100644
--- a/libcxx/test/std/localization/locales/locale/locale.cons/string.pass.cpp
+++ b/libcxx/test/std/localization/locales/locale/locale.cons/string.pass.cpp
@@ -55,7 +55,7 @@ void check(const std::locale& loc)
     assert((std::has_facet<std::messages<wchar_t> >(loc)));
 }
 
-int main()
+int main(int, char**)
 {
     {
         std::locale loc(std::string(LOCALE_ru_RU_UTF_8));
@@ -69,4 +69,6 @@ int main()
         assert(loc != loc3);
     }
     assert(globalMemCounter.checkOutstandingNewEq(0));
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locales/locale/locale.members/combine.pass.cpp b/libcxx/test/std/localization/locales/locale/locale.members/combine.pass.cpp
index 1a867fbfa6c..fc1f3d33bef 100644
--- a/libcxx/test/std/localization/locales/locale/locale.members/combine.pass.cpp
+++ b/libcxx/test/std/localization/locales/locale/locale.members/combine.pass.cpp
@@ -63,7 +63,7 @@ struct my_facet
 
 std::locale::id my_facet::id;
 
-int main()
+int main(int, char**)
 {
 {
     {
@@ -95,4 +95,6 @@ int main()
     assert(globalMemCounter.checkOutstandingNewEq(0));
 }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locales/locale/locale.members/name.pass.cpp b/libcxx/test/std/localization/locales/locale/locale.members/name.pass.cpp
index 3a6e1b98c53..96ebdf39147 100644
--- a/libcxx/test/std/localization/locales/locale/locale.members/name.pass.cpp
+++ b/libcxx/test/std/localization/locales/locale/locale.members/name.pass.cpp
@@ -17,7 +17,7 @@
 
 #include "platform_support.h" // locale name macros
 
-int main()
+int main(int, char**)
 {
     {
         std::locale loc;
@@ -27,4 +27,6 @@ int main()
         std::locale loc(LOCALE_en_US_UTF_8);
         assert(loc.name() == LOCALE_en_US_UTF_8);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locales/locale/locale.operators/compare.pass.cpp b/libcxx/test/std/localization/locales/locale/locale.operators/compare.pass.cpp
index b42e55ff67c..ea083d1370d 100644
--- a/libcxx/test/std/localization/locales/locale/locale.operators/compare.pass.cpp
+++ b/libcxx/test/std/localization/locales/locale/locale.operators/compare.pass.cpp
@@ -15,7 +15,7 @@
 #include <locale>
 #include <cassert>
 
-int main()
+int main(int, char**)
 {
     {
         std::locale l;
@@ -30,4 +30,6 @@ int main()
             assert(l(s3, s2));
         }
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locales/locale/locale.operators/eq.pass.cpp b/libcxx/test/std/localization/locales/locale/locale.operators/eq.pass.cpp
index aeb87708615..1efb487bc8d 100644
--- a/libcxx/test/std/localization/locales/locale/locale.operators/eq.pass.cpp
+++ b/libcxx/test/std/localization/locales/locale/locale.operators/eq.pass.cpp
@@ -17,7 +17,7 @@
 
 #include "platform_support.h" // locale name macros
 
-int main()
+int main(int, char**)
 {
     std::locale cloc;
     std::locale copy(cloc);
@@ -82,4 +82,6 @@ int main()
     assert(noname2 != noname1);
     assert(noname2 != nonamec);
     assert(noname2 == noname2);
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locales/locale/locale.statics/classic.pass.cpp b/libcxx/test/std/localization/locales/locale/locale.statics/classic.pass.cpp
index 9060ae27d7a..7594edcc2c6 100644
--- a/libcxx/test/std/localization/locales/locale/locale.statics/classic.pass.cpp
+++ b/libcxx/test/std/localization/locales/locale/locale.statics/classic.pass.cpp
@@ -48,11 +48,13 @@ void check(const std::locale& loc)
     assert((std::has_facet<std::messages<wchar_t> >(loc)));
 }
 
-int main()
+int main(int, char**)
 {
     std::locale loc = std::locale::classic();
     assert(loc.name() == "C");
     assert(loc == std::locale("C"));
     check(loc);
     check(std::locale("C"));
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locales/locale/locale.statics/global.pass.cpp b/libcxx/test/std/localization/locales/locale/locale.statics/global.pass.cpp
index 961bb2f4c47..57f55aa1a76 100644
--- a/libcxx/test/std/localization/locales/locale/locale.statics/global.pass.cpp
+++ b/libcxx/test/std/localization/locales/locale/locale.statics/global.pass.cpp
@@ -52,7 +52,7 @@ void check(const std::locale& loc)
     assert((std::has_facet<std::messages<wchar_t> >(loc)));
 }
 
-int main()
+int main(int, char**)
 {
     std::locale loc;
     assert(loc.name() == "C");
@@ -61,4 +61,6 @@ int main()
     std::locale loc2;
     check(loc2);
     assert(loc2 == std::locale(LOCALE_en_US_UTF_8));
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locales/locale/locale.types/locale.category/category.pass.cpp b/libcxx/test/std/localization/locales/locale/locale.types/locale.category/category.pass.cpp
index 7724ffd00ce..11c3de2975f 100644
--- a/libcxx/test/std/localization/locales/locale/locale.types/locale.category/category.pass.cpp
+++ b/libcxx/test/std/localization/locales/locale/locale.types/locale.category/category.pass.cpp
@@ -23,7 +23,7 @@ template <class T>
 void test(const T &) {}
 
 
-int main()
+int main(int, char**)
 {
     static_assert((std::is_same<std::locale::category, int>::value), "");
     assert(std::locale::none == 0);
@@ -55,4 +55,6 @@ int main()
     test(std::locale::time);
     test(std::locale::messages);
     test(std::locale::all);
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locales/locale/locale.types/locale.facet/tested_elsewhere.pass.cpp b/libcxx/test/std/localization/locales/locale/locale.types/locale.facet/tested_elsewhere.pass.cpp
index f77636c8475..1f764da05d6 100644
--- a/libcxx/test/std/localization/locales/locale/locale.types/locale.facet/tested_elsewhere.pass.cpp
+++ b/libcxx/test/std/localization/locales/locale/locale.types/locale.facet/tested_elsewhere.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locales/locale/locale.types/locale.id/tested_elsewhere.pass.cpp b/libcxx/test/std/localization/locales/locale/locale.types/locale.id/tested_elsewhere.pass.cpp
index f77636c8475..1f764da05d6 100644
--- a/libcxx/test/std/localization/locales/locale/locale.types/locale.id/tested_elsewhere.pass.cpp
+++ b/libcxx/test/std/localization/locales/locale/locale.types/locale.id/tested_elsewhere.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locales/locale/locale.types/nothing_to_do.pass.cpp b/libcxx/test/std/localization/locales/locale/locale.types/nothing_to_do.pass.cpp
index f77636c8475..1f764da05d6 100644
--- a/libcxx/test/std/localization/locales/locale/locale.types/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/localization/locales/locale/locale.types/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locales/locale/nothing_to_do.pass.cpp b/libcxx/test/std/localization/locales/locale/nothing_to_do.pass.cpp
index f77636c8475..1f764da05d6 100644
--- a/libcxx/test/std/localization/locales/locale/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/localization/locales/locale/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/locales/nothing_to_do.pass.cpp b/libcxx/test/std/localization/locales/nothing_to_do.pass.cpp
index f77636c8475..1f764da05d6 100644
--- a/libcxx/test/std/localization/locales/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/localization/locales/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }
diff --git a/libcxx/test/std/localization/localization.general/nothing_to_do.pass.cpp b/libcxx/test/std/localization/localization.general/nothing_to_do.pass.cpp
index f77636c8475..1f764da05d6 100644
--- a/libcxx/test/std/localization/localization.general/nothing_to_do.pass.cpp
+++ b/libcxx/test/std/localization/localization.general/nothing_to_do.pass.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-int main()
+int main(int, char**)
 {
+
+  return 0;
 }