[libc-commits] [libc] [libc] Set default visibility for LLVM functions (PR #116686)

[Nick Desaulniers via libc-commits]

nickdesaulniers wrote:

@jhuber6 thoughts?
```diff
diff --git a/libc/cmake/modules/LLVMLibCCompileOptionRules.cmake b/libc/cmake/modules/LLVMLibCCompileOptionRules.cmake
index 65851f1c8657..2686655f9f0f 100644
--- a/libc/cmake/modules/LLVMLibCCompileOptionRules.cmake
+++ b/libc/cmake/modules/LLVMLibCCompileOptionRules.cmake
@@ -184,7 +184,6 @@ function(_get_common_compile_options output_var flags)
   endif()
   if (LIBC_TARGET_OS_IS_GPU)
     list(APPEND compile_options "-nogpulib")
-    list(APPEND compile_options "-fvisibility=hidden")
     list(APPEND compile_options "-fconvergent-functions")
     list(APPEND compile_options "-flto")
     list(APPEND compile_options "-Wno-multi-gpu")
diff --git a/libc/src/__support/common.h b/libc/src/__support/common.h
index 45ded79f061a..92e985964f8c 100644
--- a/libc/src/__support/common.h
+++ b/libc/src/__support/common.h
@@ -21,10 +21,16 @@
 #define LLVM_LIBC_FUNCTION_ATTR
 #endif
 
+#ifdef LIBC_TARGET_ARCH_IS_GPU
+#define LIBC_PUBLIC_VIS [[gnu::visibility("hidden")]]
+#else
+#define LIBC_PUBLIC_VIS [[gnu::visibility("default")]]
+#endif
+
 // MacOS needs to be excluded because it does not support aliasing.
 #if defined(LIBC_COPT_PUBLIC_PACKAGING) && (!defined(__APPLE__))
 #define LLVM_LIBC_FUNCTION_IMPL(type, name, arglist)                           \
-  [[gnu::visibility("default")]]                                               \
+  LIBC_PUBLIC_VIS                                                              \
   LLVM_LIBC_FUNCTION_ATTR decltype(LIBC_NAMESPACE::name)                       \
       __##name##_impl__ __asm__(#name);                                        \
   decltype(LIBC_NAMESPACE::name) name [[gnu::alias(#name)]];                   \
```

https://github.com/llvm/llvm-project/pull/116686