Fix 3 bugs in filesystem tests and implementation.

This patch fixes the following bugs, all of which were discovered while
testing a 32 bit build on a 64 bit machine.

* path.itr/iterator.pass.cpp has undefined behavior.
  'path::iterator' stashes the value of the element inside the iterator.
  This violates the BiDirIterator requirements but is allowed for path::iterator.
  However this means that using reverse_iterator<path::iterator> has undefined
  behavior because it assumes that 'Iter tmp = it; return *tmp' will not create
  a dangling reference. However it does, and this caused this particular test
  to fail.

* path.native.obs/string_alloc.pass.cpp tested the SSO with a long string.
  On 32 bit builds std::wstring only has the SSO for strings of size 2. The
  test was using a string of size 4.

* fs.op.space/space.pass.cpp had overflows while calculating the expected values.
  The fix here is to convert the statvfs data members to std::uintmax_t before
  multiplying them. The internal implementation already does this but the tests
  needed to do it as well.

llvm-svn: 273078

1 files changed, 6 insertions, 3 deletions

diff --git a/libcxx/test/std/experimental/filesystem/class.path/path.member/path.native.obs/string_alloc.pass.cpp b/libcxx/test/std/experimental/filesystem/class.path/path.member/path.native.obs/string_alloc.pass.cpp
index a4039219d8c..e9832973500 100644
--- a/libcxx/test/std/experimental/filesystem/class.path/path.member/path.native.obs/string_alloc.pass.cpp
+++ b/libcxx/test/std/experimental/filesystem/class.path/path.member/path.native.obs/string_alloc.pass.cpp
@@ -30,7 +30,8 @@
 
 namespace fs = std::experimental::filesystem;
 
-MultiStringType shortString = MKSTR("abc");
+// the SSO is always triggered for strings of size 2.
+MultiStringType shortString = MKSTR("a");
 MultiStringType longString = MKSTR("abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ/123456789/abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ");
 
 template <class CharT>
@@ -43,8 +44,6 @@ void doShortStringTest(MultiStringType const& MS) {
   const path p((const char*)MS);
   {
       DisableAllocationGuard g;
-      if (!std::is_same<CharT, char>::value)
-          g.release();
       Str s = p.string<CharT>();
       assert(s == value);
       Str s2 = p.string<CharT>(Alloc{});
@@ -55,6 +54,7 @@ void doShortStringTest(MultiStringType const& MS) {
   {
       using Traits = std::char_traits<CharT>;
       using AStr = std::basic_string<CharT, Traits, MAlloc>;
+      DisableAllocationGuard g;
       AStr s = p.string<CharT, Traits, MAlloc>();
       assert(s == value);
       assert(MAlloc::alloc_count == 0);
@@ -64,6 +64,7 @@ void doShortStringTest(MultiStringType const& MS) {
   { // Other allocator - provided copy
       using Traits = std::char_traits<CharT>;
       using AStr = std::basic_string<CharT, Traits, MAlloc>;
+      DisableAllocationGuard g;
       MAlloc a;
       // don't allow another allocator to be default constructed.
       MAlloc::disable_default_constructor = true;
@@ -94,6 +95,7 @@ void doLongStringTest(MultiStringType const& MS) {
   { // Other allocator - default construct
       using Traits = std::char_traits<CharT>;
       using AStr = std::basic_string<CharT, Traits, MAlloc>;
+      DisableAllocationGuard g;
       AStr s = p.string<CharT, Traits, MAlloc>();
       assert(s == value);
       assert(MAlloc::alloc_count > 0);
@@ -103,6 +105,7 @@ void doLongStringTest(MultiStringType const& MS) {
   { // Other allocator - provided copy
       using Traits = std::char_traits<CharT>;
       using AStr = std::basic_string<CharT, Traits, MAlloc>;
+      DisableAllocationGuard g;
       MAlloc a;
       // don't allow another allocator to be default constructed.
       MAlloc::disable_default_constructor = true;