[libcxx] r339431 - [libc++] Enable aligned allocation based on feature test macro, irrespective of standard

Louis Dionne via cfe-commits cfe-commits at lists.llvm.org
Fri Aug 10 06:24:57 PDT 2018


Author: ldionne
Date: Fri Aug 10 06:24:56 2018
New Revision: 339431

URL: http://llvm.org/viewvc/llvm-project?rev=339431&view=rev
Log:
[libc++] Enable aligned allocation based on feature test macro, irrespective of standard

Summary:
The current code enables aligned allocation functions when compiling in C++17
and later. This is a problem because aligned allocation functions might not
be supported on the target platform, which leads to an error at link time.

Since r338934, Clang knows not to define __cpp_aligned_new when it's not
available on the target platform -- this commit takes advantage of that to
only use aligned allocation functions when they are available.

Reviewers: vsapsai, EricWF

Subscribers: christof, dexonsmith, cfe-commits, EricWF, mclow.lists

Differential Revision: https://reviews.llvm.org/D50344

Added:
    libcxx/trunk/test/libcxx/memory/aligned_allocation_macro.pass.cpp
Modified:
    libcxx/trunk/include/__config
    libcxx/trunk/include/new

Modified: libcxx/trunk/include/__config
URL: http://llvm.org/viewvc/llvm-project/libcxx/trunk/include/__config?rev=339431&r1=339430&r2=339431&view=diff
==============================================================================
--- libcxx/trunk/include/__config (original)
+++ libcxx/trunk/include/__config Fri Aug 10 06:24:56 2018
@@ -988,6 +988,11 @@ template <unsigned> struct __static_asse
 #  endif
 #endif // defined(__APPLE__)
 
+#if !defined(_LIBCPP_HAS_NO_ALIGNED_ALLOCATION) && \
+    !defined(_LIBCPP_BUILDING_LIBRARY) && \
+    (!defined(__cpp_aligned_new) || __cpp_aligned_new < 201606)
+#  define _LIBCPP_HAS_NO_ALIGNED_ALLOCATION
+#endif
 
 #if defined(__APPLE__) || defined(__FreeBSD__)
 #define _LIBCPP_HAS_DEFAULTRUNELOCALE

Modified: libcxx/trunk/include/new
URL: http://llvm.org/viewvc/llvm-project/libcxx/trunk/include/new?rev=339431&r1=339430&r2=339431&view=diff
==============================================================================
--- libcxx/trunk/include/new (original)
+++ libcxx/trunk/include/new Fri Aug 10 06:24:56 2018
@@ -108,13 +108,6 @@ void  operator delete[](void* ptr, void*
 # define _LIBCPP_HAS_NO_SIZED_DEALLOCATION
 #endif
 
-#if !defined(_LIBCPP_HAS_NO_ALIGNED_ALLOCATION) && \
-    (!(defined(_LIBCPP_BUILDING_LIBRARY) || _LIBCPP_STD_VER > 14 || \
-    (defined(__cpp_aligned_new) && __cpp_aligned_new >= 201606)))
-# define _LIBCPP_HAS_NO_ALIGNED_ALLOCATION
-#endif
-
-
 #if !__has_builtin(__builtin_operator_new) || \
    __has_builtin(__builtin_operator_new) < 201802L || \
    defined(_LIBCPP_HAS_NO_ALIGNED_ALLOCATION) || \

Added: libcxx/trunk/test/libcxx/memory/aligned_allocation_macro.pass.cpp
URL: http://llvm.org/viewvc/llvm-project/libcxx/trunk/test/libcxx/memory/aligned_allocation_macro.pass.cpp?rev=339431&view=auto
==============================================================================
--- libcxx/trunk/test/libcxx/memory/aligned_allocation_macro.pass.cpp (added)
+++ libcxx/trunk/test/libcxx/memory/aligned_allocation_macro.pass.cpp Fri Aug 10 06:24:56 2018
@@ -0,0 +1,25 @@
+//===----------------------------------------------------------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is dual licensed under the MIT and the University of Illinois Open
+// Source Licenses. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++98, c++03, c++11, c++14
+// XFAIL: with_system_cxx_lib=macosx10.12
+// XFAIL: with_system_cxx_lib=macosx10.11
+// XFAIL: with_system_cxx_lib=macosx10.10
+// XFAIL: with_system_cxx_lib=macosx10.9
+// XFAIL: with_system_cxx_lib=macosx10.8
+// XFAIL: with_system_cxx_lib=macosx10.7
+
+#include <new>
+
+
+#ifdef _LIBCPP_HAS_NO_ALIGNED_ALLOCATION
+#   error "libc++ should have aligned allocation in C++17 and up when targeting a platform that supports it"
+#endif
+
+int main() { }




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