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

45 files changed, 135 insertions, 45 deletions

diff --git a/libcxx/test/std/containers/sequences/vector.bool/assign_copy.pass.cpp b/libcxx/test/std/containers/sequences/vector.bool/assign_copy.pass.cpp
index cffc3bfff0f..5aa86839ff4 100644
--- a/libcxx/test/std/containers/sequences/vector.bool/assign_copy.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector.bool/assign_copy.pass.cpp
@@ -15,7 +15,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         std::vector<bool, test_allocator<bool> > l(3, true, test_allocator<bool>(5));
@@ -40,4 +40,6 @@ int main()
         assert(l2.get_allocator() == min_allocator<bool>());
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector.bool/assign_initializer_list.pass.cpp b/libcxx/test/std/containers/sequences/vector.bool/assign_initializer_list.pass.cpp
index 36d32c73c73..bbd980bd325 100644
--- a/libcxx/test/std/containers/sequences/vector.bool/assign_initializer_list.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector.bool/assign_initializer_list.pass.cpp
@@ -17,7 +17,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     std::vector<bool> d;
@@ -37,4 +37,6 @@ int main()
     assert(d[2] == false);
     assert(d[3] == true);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector.bool/assign_move.pass.cpp b/libcxx/test/std/containers/sequences/vector.bool/assign_move.pass.cpp
index 59fb08fbf23..b70e9cde65b 100644
--- a/libcxx/test/std/containers/sequences/vector.bool/assign_move.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector.bool/assign_move.pass.cpp
@@ -17,7 +17,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         std::vector<bool, test_allocator<bool> > l(test_allocator<bool>(5));
@@ -75,4 +75,6 @@ int main()
         assert(l.empty());
         assert(l2.get_allocator() == lo.get_allocator());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector.bool/capacity.pass.cpp b/libcxx/test/std/containers/sequences/vector.bool/capacity.pass.cpp
index 14ebc6c1e63..e24ebe00c6a 100644
--- a/libcxx/test/std/containers/sequences/vector.bool/capacity.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector.bool/capacity.pass.cpp
@@ -16,7 +16,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         std::vector<bool> v;
@@ -40,4 +40,6 @@ int main()
         assert(v.capacity() >= 101);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector.bool/construct_default.pass.cpp b/libcxx/test/std/containers/sequences/vector.bool/construct_default.pass.cpp
index e481ece9f71..3fd2bf8d195 100644
--- a/libcxx/test/std/containers/sequences/vector.bool/construct_default.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector.bool/construct_default.pass.cpp
@@ -59,7 +59,7 @@ test1(const typename C::allocator_type& a)
     assert(c.get_allocator() == a);
 }
 
-int main()
+int main(int, char**)
 {
     {
     test0<std::vector<bool> >();
@@ -75,4 +75,6 @@ int main()
     test1<std::vector<bool, explicit_allocator<bool> > >(explicit_allocator<bool>());
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector.bool/construct_iter_iter.pass.cpp b/libcxx/test/std/containers/sequences/vector.bool/construct_iter_iter.pass.cpp
index 44931a75c6a..e20f300982c 100644
--- a/libcxx/test/std/containers/sequences/vector.bool/construct_iter_iter.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector.bool/construct_iter_iter.pass.cpp
@@ -30,7 +30,7 @@ test(Iterator first, Iterator last)
         assert(*i == *first);
 }
 
-int main()
+int main(int, char**)
 {
     bool a[] = {0, 1, 0, 0, 1, 1, 1, 0, 0, 1, 0, 0, 0, 1, 1, 0, 1, 0};
     bool* an = a + sizeof(a)/sizeof(a[0]);
@@ -46,4 +46,6 @@ int main()
     test<std::vector<bool, min_allocator<bool>> >(random_access_iterator<const bool*>(a), random_access_iterator<const bool*>(an));
     test<std::vector<bool, min_allocator<bool>> >(a, an);
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector.bool/construct_iter_iter_alloc.pass.cpp b/libcxx/test/std/containers/sequences/vector.bool/construct_iter_iter_alloc.pass.cpp
index 49d2c23e0ea..2aa2b42648f 100644
--- a/libcxx/test/std/containers/sequences/vector.bool/construct_iter_iter_alloc.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector.bool/construct_iter_iter_alloc.pass.cpp
@@ -31,7 +31,7 @@ test(Iterator first, Iterator last, const typename C::allocator_type& a)
         assert(*i == *first);
 }
 
-int main()
+int main(int, char**)
 {
     bool a[] = {0, 1, 0, 0, 1, 1, 1, 0, 0, 1, 0, 0, 0, 1, 1, 0, 1, 0};
     bool* an = a + sizeof(a)/sizeof(a[0]);
@@ -53,4 +53,6 @@ int main()
     test<std::vector<bool, min_allocator<bool>> >(a, an, alloc);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector.bool/construct_size.pass.cpp b/libcxx/test/std/containers/sequences/vector.bool/construct_size.pass.cpp
index 8300924b6d0..2763df7e11d 100644
--- a/libcxx/test/std/containers/sequences/vector.bool/construct_size.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector.bool/construct_size.pass.cpp
@@ -56,11 +56,13 @@ test(typename C::size_type n)
     test2<C> ( n );
 }
 
-int main()
+int main(int, char**)
 {
     test<std::vector<bool> >(50);
 #if TEST_STD_VER >= 11
     test<std::vector<bool, min_allocator<bool>> >(50);
     test2<std::vector<bool, test_allocator<bool>> >( 100, test_allocator<bool>(23));
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector.bool/construct_size_value.pass.cpp b/libcxx/test/std/containers/sequences/vector.bool/construct_size_value.pass.cpp
index ecde4267809..068989330a3 100644
--- a/libcxx/test/std/containers/sequences/vector.bool/construct_size_value.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector.bool/construct_size_value.pass.cpp
@@ -28,10 +28,12 @@ test(typename C::size_type n, const typename C::value_type& x)
         assert(*i == x);
 }
 
-int main()
+int main(int, char**)
 {
     test<std::vector<bool> >(50, true);
 #if TEST_STD_VER >= 11
     test<std::vector<bool, min_allocator<bool>> >(50, true);
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector.bool/construct_size_value_alloc.pass.cpp b/libcxx/test/std/containers/sequences/vector.bool/construct_size_value_alloc.pass.cpp
index c9439246560..e19f3c4a9d5 100644
--- a/libcxx/test/std/containers/sequences/vector.bool/construct_size_value_alloc.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector.bool/construct_size_value_alloc.pass.cpp
@@ -30,10 +30,12 @@ test(typename C::size_type n, const typename C::value_type& x,
         assert(*i == x);
 }
 
-int main()
+int main(int, char**)
 {
     test<std::vector<bool> >(50, true, std::allocator<bool>());
 #if TEST_STD_VER >= 11
     test<std::vector<bool, min_allocator<bool>> >(50, true, min_allocator<bool>());
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector.bool/copy.pass.cpp b/libcxx/test/std/containers/sequences/vector.bool/copy.pass.cpp
index 66a15a4c861..618a37faf70 100644
--- a/libcxx/test/std/containers/sequences/vector.bool/copy.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector.bool/copy.pass.cpp
@@ -29,7 +29,7 @@ test(const C& x)
     assert(c == x);
 }
 
-int main()
+int main(int, char**)
 {
     {
         bool a[] = {0, 1, 0, 0, 1, 1, 1, 0, 0, 1, 0, 0, 0, 1, 1, 0, 1, 0};
@@ -61,4 +61,6 @@ int main()
         assert(v2.get_allocator() == v.get_allocator());
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector.bool/copy_alloc.pass.cpp b/libcxx/test/std/containers/sequences/vector.bool/copy_alloc.pass.cpp
index 9a63e5a555d..7970b2c7ed9 100644
--- a/libcxx/test/std/containers/sequences/vector.bool/copy_alloc.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector.bool/copy_alloc.pass.cpp
@@ -28,7 +28,7 @@ test(const C& x, const typename C::allocator_type& a)
     assert(c == x);
 }
 
-int main()
+int main(int, char**)
 {
     {
         bool a[] = {0, 1, 0, 0, 1, 1, 1, 0, 0, 1, 0, 0, 0, 1, 1, 0, 1, 0};
@@ -60,4 +60,6 @@ int main()
         assert(l2.get_allocator() == min_allocator<bool>());
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector.bool/default_noexcept.pass.cpp b/libcxx/test/std/containers/sequences/vector.bool/default_noexcept.pass.cpp
index bffeaf64c74..800bd1b4b1c 100644
--- a/libcxx/test/std/containers/sequences/vector.bool/default_noexcept.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector.bool/default_noexcept.pass.cpp
@@ -30,7 +30,7 @@ struct some_alloc
     some_alloc(const some_alloc&);
 };
 
-int main()
+int main(int, char**)
 {
 #if defined(_LIBCPP_VERSION)
     {
@@ -50,4 +50,6 @@ int main()
         static_assert(!std::is_nothrow_default_constructible<C>::value, "");
     }
 #endif // _LIBCPP_VERSION
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector.bool/dtor_noexcept.pass.cpp b/libcxx/test/std/containers/sequences/vector.bool/dtor_noexcept.pass.cpp
index 9d7858b4f8c..949add271a2 100644
--- a/libcxx/test/std/containers/sequences/vector.bool/dtor_noexcept.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector.bool/dtor_noexcept.pass.cpp
@@ -26,7 +26,7 @@ struct some_alloc
     ~some_alloc() noexcept(false);
 };
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::vector<bool> C;
@@ -46,4 +46,6 @@ int main()
         static_assert(!std::is_nothrow_destructible<C>::value, "");
     }
 #endif // _LIBCPP_VERSION
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector.bool/emplace.pass.cpp b/libcxx/test/std/containers/sequences/vector.bool/emplace.pass.cpp
index 26b9039073c..129cbff154e 100644
--- a/libcxx/test/std/containers/sequences/vector.bool/emplace.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector.bool/emplace.pass.cpp
@@ -16,7 +16,7 @@
 #include <cassert>
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::vector<bool> C;
@@ -63,4 +63,6 @@ int main()
         assert(c[1] == true);
         assert(c.back() == true);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector.bool/emplace_back.pass.cpp b/libcxx/test/std/containers/sequences/vector.bool/emplace_back.pass.cpp
index 0ad72100214..974b7c24ac7 100644
--- a/libcxx/test/std/containers/sequences/vector.bool/emplace_back.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector.bool/emplace_back.pass.cpp
@@ -18,7 +18,7 @@
 #include "test_macros.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef std::vector<bool> C;
@@ -87,4 +87,6 @@ int main()
         assert(c[1] == true);
         assert(c.back() == true);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector.bool/empty.fail.cpp b/libcxx/test/std/containers/sequences/vector.bool/empty.fail.cpp
index 0381d7eb24b..0a84eb79d12 100644
--- a/libcxx/test/std/containers/sequences/vector.bool/empty.fail.cpp
+++ b/libcxx/test/std/containers/sequences/vector.bool/empty.fail.cpp
@@ -20,8 +20,10 @@
 
 #include "test_macros.h"
 
-int main ()
+int main(int, char**)
 {
     std::vector<bool> c;
     c.empty();  // expected-error {{ignoring return value of function declared with 'nodiscard' attribute}}
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector.bool/empty.pass.cpp b/libcxx/test/std/containers/sequences/vector.bool/empty.pass.cpp
index e3226a12835..e0c0243e139 100644
--- a/libcxx/test/std/containers/sequences/vector.bool/empty.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector.bool/empty.pass.cpp
@@ -18,7 +18,7 @@
 #include "test_macros.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::vector<bool> C;
@@ -42,4 +42,6 @@ int main()
     assert(c.empty());
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector.bool/enabled_hash.pass.cpp b/libcxx/test/std/containers/sequences/vector.bool/enabled_hash.pass.cpp
index ba8bdf5312a..f6631cf2d49 100644
--- a/libcxx/test/std/containers/sequences/vector.bool/enabled_hash.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector.bool/enabled_hash.pass.cpp
@@ -18,10 +18,12 @@
 #include "poisoned_hash_helper.hpp"
 #include "min_allocator.h"
 
-int main() {
+int main(int, char**) {
   test_library_hash_specializations_available();
   {
     test_hash_enabled_for_type<std::vector<bool> >();
     test_hash_enabled_for_type<std::vector<bool, min_allocator<bool>>>();
   }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector.bool/erase_iter.pass.cpp b/libcxx/test/std/containers/sequences/vector.bool/erase_iter.pass.cpp
index b0a65c9ae27..c3d6bfd5de0 100644
--- a/libcxx/test/std/containers/sequences/vector.bool/erase_iter.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector.bool/erase_iter.pass.cpp
@@ -16,7 +16,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     bool a1[] = {1, 0, 1};
     {
@@ -61,4 +61,6 @@ int main()
     assert(distance(l1.begin(), l1.end()) == 0);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector.bool/erase_iter_iter.pass.cpp b/libcxx/test/std/containers/sequences/vector.bool/erase_iter_iter.pass.cpp
index b574552309a..89763017e97 100644
--- a/libcxx/test/std/containers/sequences/vector.bool/erase_iter_iter.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector.bool/erase_iter_iter.pass.cpp
@@ -16,7 +16,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     bool a1[] = {1, 0, 1};
     {
@@ -81,4 +81,6 @@ int main()
         assert(i == l1.begin());
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector.bool/find.pass.cpp b/libcxx/test/std/containers/sequences/vector.bool/find.pass.cpp
index 265b519de78..883b5b4dbca 100644
--- a/libcxx/test/std/containers/sequences/vector.bool/find.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector.bool/find.pass.cpp
@@ -18,7 +18,7 @@
 #include <cassert>
 #include <cstddef>
 
-int main()
+int main(int, char**)
 {
     {
         for (unsigned i = 1; i < 256; ++i)
@@ -38,4 +38,6 @@ int main()
             assert(b.end() == j);
         }
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector.bool/initializer_list.pass.cpp b/libcxx/test/std/containers/sequences/vector.bool/initializer_list.pass.cpp
index 9f99675896f..d510b86fed0 100644
--- a/libcxx/test/std/containers/sequences/vector.bool/initializer_list.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector.bool/initializer_list.pass.cpp
@@ -17,7 +17,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     std::vector<bool> d = {true, false, false, true};
@@ -35,4 +35,6 @@ int main()
     assert(d[2] == false);
     assert(d[3] == true);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector.bool/initializer_list_alloc.pass.cpp b/libcxx/test/std/containers/sequences/vector.bool/initializer_list_alloc.pass.cpp
index 29164b598e6..27d8420a6df 100644
--- a/libcxx/test/std/containers/sequences/vector.bool/initializer_list_alloc.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector.bool/initializer_list_alloc.pass.cpp
@@ -18,7 +18,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     std::vector<bool, test_allocator<bool>> d({true, false, false, true}, test_allocator<bool>(3));
@@ -38,4 +38,6 @@ int main()
     assert(d[2] == false);
     assert(d[3] == true);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector.bool/insert_iter_initializer_list.pass.cpp b/libcxx/test/std/containers/sequences/vector.bool/insert_iter_initializer_list.pass.cpp
index 3760a9611bb..519752da103 100644
--- a/libcxx/test/std/containers/sequences/vector.bool/insert_iter_initializer_list.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector.bool/insert_iter_initializer_list.pass.cpp
@@ -17,7 +17,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     std::vector<bool> d(10, true);
@@ -59,4 +59,6 @@ int main()
     assert(d[12] == true);
     assert(d[13] == true);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector.bool/insert_iter_iter_iter.pass.cpp b/libcxx/test/std/containers/sequences/vector.bool/insert_iter_iter_iter.pass.cpp
index 7180bb8c28b..b9a92189169 100644
--- a/libcxx/test/std/containers/sequences/vector.bool/insert_iter_iter_iter.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector.bool/insert_iter_iter_iter.pass.cpp
@@ -20,7 +20,7 @@
 #include "test_iterators.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         std::vector<bool> v(100);
@@ -125,4 +125,6 @@ int main()
             assert(v[j] == 0);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector.bool/insert_iter_size_value.pass.cpp b/libcxx/test/std/containers/sequences/vector.bool/insert_iter_size_value.pass.cpp
index 9e13af2ac7d..5774ab5f6ca 100644
--- a/libcxx/test/std/containers/sequences/vector.bool/insert_iter_size_value.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector.bool/insert_iter_size_value.pass.cpp
@@ -17,7 +17,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         std::vector<bool> v(100);
@@ -78,4 +78,6 @@ int main()
             assert(v[j] == 0);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector.bool/insert_iter_value.pass.cpp b/libcxx/test/std/containers/sequences/vector.bool/insert_iter_value.pass.cpp
index 1c0e8ed03a8..2502865c78e 100644
--- a/libcxx/test/std/containers/sequences/vector.bool/insert_iter_value.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector.bool/insert_iter_value.pass.cpp
@@ -17,7 +17,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         std::vector<bool> v(100);
@@ -74,4 +74,6 @@ int main()
             assert(v[j] == 0);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector.bool/iterators.pass.cpp b/libcxx/test/std/containers/sequences/vector.bool/iterators.pass.cpp
index 0780d1dd093..7714e53b2cd 100644
--- a/libcxx/test/std/containers/sequences/vector.bool/iterators.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector.bool/iterators.pass.cpp
@@ -22,7 +22,7 @@
 #include "test_macros.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         typedef bool T;
@@ -120,4 +120,6 @@ int main()
         assert (ii1 - cii == 0);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector.bool/move.pass.cpp b/libcxx/test/std/containers/sequences/vector.bool/move.pass.cpp
index e5752e08437..4de0604c6a7 100644
--- a/libcxx/test/std/containers/sequences/vector.bool/move.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector.bool/move.pass.cpp
@@ -18,7 +18,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         std::vector<bool, test_allocator<bool> > l(test_allocator<bool>(5));
@@ -89,4 +89,6 @@ int main()
         assert(a.get_data() == 42);
       }
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector.bool/move_alloc.pass.cpp b/libcxx/test/std/containers/sequences/vector.bool/move_alloc.pass.cpp
index bcf57b6c2c3..f2ff5303b0f 100644
--- a/libcxx/test/std/containers/sequences/vector.bool/move_alloc.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector.bool/move_alloc.pass.cpp
@@ -17,7 +17,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         std::vector<bool, test_allocator<bool> > l(test_allocator<bool>(5));
@@ -71,4 +71,6 @@ int main()
         assert(l.empty());
         assert(l2.get_allocator() == min_allocator<bool>());
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector.bool/move_assign_noexcept.pass.cpp b/libcxx/test/std/containers/sequences/vector.bool/move_assign_noexcept.pass.cpp
index 60517e20653..6c7fcfca75c 100644
--- a/libcxx/test/std/containers/sequences/vector.bool/move_assign_noexcept.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector.bool/move_assign_noexcept.pass.cpp
@@ -56,7 +56,7 @@ struct some_alloc3
     typedef std::false_type is_always_equal;
 };
 
-int main()
+int main(int, char**)
 {
 #if defined(_LIBCPP_VERSION)
     {
@@ -97,4 +97,6 @@ int main()
         static_assert(!std::is_nothrow_move_assignable<C>::value, "");
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector.bool/move_noexcept.pass.cpp b/libcxx/test/std/containers/sequences/vector.bool/move_noexcept.pass.cpp
index 8326e4c4271..a59e1a8eb94 100644
--- a/libcxx/test/std/containers/sequences/vector.bool/move_noexcept.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector.bool/move_noexcept.pass.cpp
@@ -28,7 +28,7 @@ struct some_alloc
     some_alloc(const some_alloc&);
 };
 
-int main()
+int main(int, char**)
 {
 #if defined(_LIBCPP_VERSION)
     {
@@ -56,4 +56,6 @@ int main()
         static_assert(!std::is_nothrow_move_constructible<C>::value, "");
 #endif
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector.bool/op_equal_initializer_list.pass.cpp b/libcxx/test/std/containers/sequences/vector.bool/op_equal_initializer_list.pass.cpp
index 5263fa3bd3a..22384fe8d06 100644
--- a/libcxx/test/std/containers/sequences/vector.bool/op_equal_initializer_list.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector.bool/op_equal_initializer_list.pass.cpp
@@ -17,7 +17,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     std::vector<bool> d;
@@ -37,4 +37,6 @@ int main()
     assert(d[2] == false);
     assert(d[3] == true);
     }
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector.bool/push_back.pass.cpp b/libcxx/test/std/containers/sequences/vector.bool/push_back.pass.cpp
index 2e7d82d961b..438869be16c 100644
--- a/libcxx/test/std/containers/sequences/vector.bool/push_back.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector.bool/push_back.pass.cpp
@@ -17,7 +17,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         bool a[] = {0, 1, 1, 0, 1, 0, 0};
@@ -45,4 +45,6 @@ int main()
         }
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector.bool/reference.swap.pass.cpp b/libcxx/test/std/containers/sequences/vector.bool/reference.swap.pass.cpp
index 22e10914225..c41bac18836 100644
--- a/libcxx/test/std/containers/sequences/vector.bool/reference.swap.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector.bool/reference.swap.pass.cpp
@@ -16,7 +16,7 @@
 
 #include "test_macros.h"
 
-int main()
+int main(int, char**)
 {
 
     bool a[] = {false, true, false, true};
@@ -35,4 +35,6 @@ int main()
     v.swap(r1, r2);
     assert( r1);
     assert(!r2);
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector.bool/reserve.pass.cpp b/libcxx/test/std/containers/sequences/vector.bool/reserve.pass.cpp
index b7430453fae..039c1bc18fa 100644
--- a/libcxx/test/std/containers/sequences/vector.bool/reserve.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector.bool/reserve.pass.cpp
@@ -16,7 +16,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         std::vector<bool> v;
@@ -50,4 +50,6 @@ int main()
         assert(v.capacity() >= 150);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector.bool/resize_size.pass.cpp b/libcxx/test/std/containers/sequences/vector.bool/resize_size.pass.cpp
index 3d926910ce7..53e83ac7eff 100644
--- a/libcxx/test/std/containers/sequences/vector.bool/resize_size.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector.bool/resize_size.pass.cpp
@@ -16,7 +16,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         std::vector<bool> v(100);
@@ -46,4 +46,6 @@ int main()
         assert(v.capacity() >= 400);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector.bool/resize_size_value.pass.cpp b/libcxx/test/std/containers/sequences/vector.bool/resize_size_value.pass.cpp
index 061f8a505e4..ef0cb6160c6 100644
--- a/libcxx/test/std/containers/sequences/vector.bool/resize_size_value.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector.bool/resize_size_value.pass.cpp
@@ -16,7 +16,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         std::vector<bool> v(100);
@@ -48,4 +48,6 @@ int main()
             assert(v[i] == 1);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector.bool/shrink_to_fit.pass.cpp b/libcxx/test/std/containers/sequences/vector.bool/shrink_to_fit.pass.cpp
index 988ce6e03bf..59714d5fb5c 100644
--- a/libcxx/test/std/containers/sequences/vector.bool/shrink_to_fit.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector.bool/shrink_to_fit.pass.cpp
@@ -16,7 +16,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         std::vector<bool> v(100);
@@ -34,4 +34,6 @@ int main()
         assert(v.size() >= 101);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector.bool/size.pass.cpp b/libcxx/test/std/containers/sequences/vector.bool/size.pass.cpp
index d8abef9893f..db737c930c3 100644
--- a/libcxx/test/std/containers/sequences/vector.bool/size.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector.bool/size.pass.cpp
@@ -18,7 +18,7 @@
 #include "test_macros.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::vector<bool> C;
@@ -58,4 +58,6 @@ int main()
     assert(c.size() == 0);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector.bool/swap.pass.cpp b/libcxx/test/std/containers/sequences/vector.bool/swap.pass.cpp
index 9aa579d4a6d..9ff11113d82 100644
--- a/libcxx/test/std/containers/sequences/vector.bool/swap.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector.bool/swap.pass.cpp
@@ -16,7 +16,7 @@
 #include "test_allocator.h"
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
         std::vector<bool> v1(100);
@@ -94,4 +94,6 @@ int main()
         assert(v[1] == true);
     }
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector.bool/swap_noexcept.pass.cpp b/libcxx/test/std/containers/sequences/vector.bool/swap_noexcept.pass.cpp
index dbf0f821f13..e346c29983f 100644
--- a/libcxx/test/std/containers/sequences/vector.bool/swap_noexcept.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector.bool/swap_noexcept.pass.cpp
@@ -52,7 +52,7 @@ struct some_alloc2
     typedef std::true_type is_always_equal;
 };
 
-int main()
+int main(int, char**)
 {
 #if defined(_LIBCPP_VERSION)
     {
@@ -89,4 +89,6 @@ int main()
     }
 #endif // _LIBCPP_VERSION
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector.bool/types.pass.cpp b/libcxx/test/std/containers/sequences/vector.bool/types.pass.cpp
index 4736f8ac976..d15973a38b1 100644
--- a/libcxx/test/std/containers/sequences/vector.bool/types.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector.bool/types.pass.cpp
@@ -67,7 +67,7 @@ test()
         std::reverse_iterator<typename C::const_iterator> >::value), "");
 }
 
-int main()
+int main(int, char**)
 {
     test<test_allocator<bool> >();
     test<std::allocator<bool> >();
@@ -76,4 +76,6 @@ int main()
 #if TEST_STD_VER >= 11
     test<min_allocator<bool> >();
 #endif
+
+  return 0;
 }
diff --git a/libcxx/test/std/containers/sequences/vector.bool/vector_bool.pass.cpp b/libcxx/test/std/containers/sequences/vector.bool/vector_bool.pass.cpp
index c0d27e4d294..5f9ae3decb6 100644
--- a/libcxx/test/std/containers/sequences/vector.bool/vector_bool.pass.cpp
+++ b/libcxx/test/std/containers/sequences/vector.bool/vector_bool.pass.cpp
@@ -23,7 +23,7 @@
 
 #include "min_allocator.h"
 
-int main()
+int main(int, char**)
 {
     {
     typedef std::vector<bool> T;
@@ -50,4 +50,6 @@ int main()
     assert(h(vb) != 0);
     }
 #endif
+
+  return 0;
 }