[libc-commits] [libc] [libc] Add _Returns_twice to C++ code (PR #153602)

[Petr Hosek via libc-commits]

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@@ -47,6 +47,9 @@
 #define __NOEXCEPT throw()
 #endif
 
+#undef _Returns_twice
+#define _Returns_twice [[gnu::returns_twice]]
+
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petrhosek wrote:

The `[[attribute]]` was only introduced in C20 so we shouldn't be using it in C code since we want to make sure our headers are compatible with older C standards.

https://github.com/llvm/llvm-project/pull/153602