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Re: [PATCH] PR libstdc++/80446 cope with libc defining __has_builtin

On 19/04/17 11:49 +0100, Jonathan Wakely wrote:
Both newlib and FreeBSD have this in libc headers:

#ifndef __has_builtin
#define __has_builtin(x) 0

This means our attempts to use #ifdef __has_builtin aren't reliable,
so we need a different approach. With this patch we don't care whether
it's defined or not, only its value.

	PR libstdc++/80446
	* include/std/type_traits (is_aggregate): Change __has_builtin checks.
	* libsupc++/new (launder): Likewise.

Tested ppc64le-linux and x86_64-freebsd11.0, committed to trunk.

Jakub pointed out I forgot to update the macro name in a comment.

Smoke-tested and committed to trunk.

commit be2fd5feb898fefac9f97ffca6691b232d18fa5b
Author: Jonathan Wakely <>
Date:   Wed Apr 19 16:11:34 2017 +0100

    	* libsupc++/new: Update comment on #endif directive.

diff --git a/libstdc++-v3/libsupc++/new b/libstdc++-v3/libsupc++/new
index 2de7752..04f172c 100644
--- a/libstdc++-v3/libsupc++/new
+++ b/libstdc++-v3/libsupc++/new
@@ -209,7 +209,7 @@ namespace std
   void launder(volatile void*) = delete;
   void launder(const volatile void*) = delete;
 #endif // C++17

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