[PATCH] D54814: Move internal usages of `alignof`/`__alignof` to use `_LIBCPP_ALIGNOF`.

[Louis Dionne via Phabricator]

ldionne added a comment.

Please hold off with committing this until we've agreed on the ABI part. That'll take at least until next week when people are back from Thanksgiving.



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Comment at: include/__config:1285
+#ifndef _LIBCPP_CXX03_LANG
+#define _LIBCPP_ALIGNOF(_Tp) alignof(_Tp)
+#elif defined(_LIBCPP_COMPILER_CLANG)
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Can you indent nested `#define`s? I find it very difficult to read our PP code because it often lacks indentation.


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Comment at: test/libcxx/libcpp_alignof.pass.cpp:29
+#ifdef TEST_COMPILER_CLANG
+  static_assert(_LIBCPP_ALIGNOF(T) == _Alignof(T), "");
+#endif
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Why is this test useful? Isn't the previous one (for C++11) sufficient?


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Comment at: test/support/test_macros.h:118
 #else
-#define TEST_ALIGNOF(...) __alignof(__VA_ARGS__)
+#if defined(TEST_COMPILER_CLANG)
+# define TEST_ALIGNOF(...) _Alignof(__VA_ARGS__)
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Why not always just `alignof`? Shouldn't we only use that macro in C++11 and above anyway?


Repository:
  rCXX libc++

https://reviews.llvm.org/D54814