[libc-commits] [libc] [libc][math] implement `signbit` (PR #97791)

[via libc-commits]

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@@ -79,3 +79,13 @@ add_libc_test(
   DEPENDS
     libc.include.llvm-libc-macros.stdckdint_macros
 )
+
+add_libc_test(
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lntue wrote:

In addition to the C++ test to make sure that the implementation is correct, also add a light-weight C test similar to https://github.com/llvm/llvm-project/blob/main/libc/test/include/CMakeLists.txt#L49 to make sure that the macro definitions work in C.

https://github.com/llvm/llvm-project/pull/97791