[libcxx] r209032 - Merging r201843

[Tom Stellard]

Author: tstellar
Date: Fri May 16 16:31:35 2014
New Revision: 209032

URL: http://llvm.org/viewvc/llvm-project?rev=209032&view=rev
Log:
Merging r201843

------------------------------------------------------------------------
r201843 | chandlerc | 2014-02-21 00:37:30 -0800 (Fri, 21 Feb 2014) | 4 lines

Teach libc++ to use the compiler-provided C-compatible ::max_align_t
rather than its own type for std::max_align_t. This is particularly
relevant as the types may not be ABI compatible despite users expecting
them to be.
------------------------------------------------------------------------

Modified:
    libcxx/branches/release_34/   (props changed)
    libcxx/branches/release_34/include/cstddef

Propchange: libcxx/branches/release_34/
------------------------------------------------------------------------------
--- svn:mergeinfo (original)
+++ svn:mergeinfo Fri May 16 16:31:35 2014
@@ -1,2 +1,2 @@
 /libcxx/branches/apple:136569-137939
-/libcxx/trunk:195136,195143,195693,196058,197061,197314
+/libcxx/trunk:195136,195143,195693,196058,197061,197314,201843

Modified: libcxx/branches/release_34/include/cstddef
URL: http://llvm.org/viewvc/llvm-project/libcxx/branches/release_34/include/cstddef?rev=209032&r1=209031&r2=209032&view=diff
==============================================================================
--- libcxx/branches/release_34/include/cstddef (original)
+++ libcxx/branches/release_34/include/cstddef Fri May 16 16:31:35 2014
@@ -52,7 +52,12 @@ _LIBCPP_BEGIN_NAMESPACE_STD
 using ::ptrdiff_t;
 using ::size_t;
 
+#if defined(__CLANG_MAX_ALIGN_T_DEFINED) || defined(_GCC_MAX_ALIGN_T)
+// Re-use the compiler's <stddef.h> max_align_t where possible.
+using ::max_align_t;
+#else
 typedef long double max_align_t;
+#endif
 
 #ifdef _LIBCPP_HAS_NO_NULLPTR