[libc++] Only include <setjmp.h> from the C library if it exists #81887
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llvmbot added the libc++ 
| @llvm/pr-subscribers-libcxx Author: Louis Dionne (ldionne) ChangesIn 2cea1ba, we removed the <setjmp.h> header provided by libc++. However, we did not conditionally include the underlying <setjmp.h> header only if the C library provides one, which we otherwise do consistently (see e.g. 647ddc0). rdar://122978778 Full diff: https://github.com/llvm/llvm-project/pull/81887.diff 1 Files Affected:
diff --git a/libcxx/include/csetjmp b/libcxx/include/csetjmp index d219c8e6cb2250..9012cad22ebe74 100644 --- a/libcxx/include/csetjmp +++ b/libcxx/include/csetjmp @@ -33,7 +33,13 @@ void longjmp(jmp_buf env, int val); #include <__assert> // all public C++ headers provide the assertion handler #include <__config> -#include <setjmp.h> +// <setjmp.h> is not provided by libc++ +#if __has_include(<setjmp.h>) +# include <setjmp.h> +# ifdef _LIBCPP_SETJMP_H +# error "If libc++ starts defining <setjmp.h>, the __has_include check should move to libc++'s <setjmp.h>" +# endif +#endif #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER) # pragma GCC system_header |
| This broke some code downstream and we think this could have a negative impact on freestanding users (who are most likely not to have a |
| Does this need to be backported to the release branch? |
Yes, sorry I am going OOO and I forgot to merge this one. Merged from my phone just now. /cherry-pick d8278b6 |
| /pull-request #82045 |
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In 2cea1ba, we removed the <setjmp.h> header provided by libc++. However, we did not conditionally include the underlying <setjmp.h> header only if the C library provides one, which we otherwise do consistently (see e.g. 647ddc0).
rdar://122978778