[libc-commits] [libc] [libc] Move from alias(X) to asm(X) for aliasing (PR #89333)

[Nick Desaulniers via libc-commits]

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@@ -25,7 +25,7 @@
 #define LLVM_LIBC_FUNCTION_IMPL(type, name, arglist)                           \
   LLVM_LIBC_FUNCTION_ATTR decltype(LIBC_NAMESPACE::name)                       \
       __##name##_impl__ __asm__(#name);                                        \
-  decltype(LIBC_NAMESPACE::name) name [[gnu::alias(#name)]];                   \
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nickdesaulniers wrote:

How does this macro result in two symbols in the emitted binary, one non-mangled, and one mangled wrt. the namespace?  If I extract out this macro, I only see the non-mangled name.

https://godbolt.org/z/oedsKxroP

But for full build, if you run `llvm-readelf -s <build dir>/libc/lib/libc.a` you see the pairs of symbol names.

There's something else I'm missing here...

https://github.com/llvm/llvm-project/pull/89333