[libc++] Disable -Wattributes in GCC

Currently GCC produces lots of warnings. Most of them are `-Wattributes`, but these warnings are completly ignored by everybody. So let's disable -Wattributes and make the output cleaner.

Reviewed By: ldionne, #libc

Spies: libcxx-commits, mgorny

Differential Revision: https://reviews.llvm.org/D119140

diff --git a/libcxx/CMakeLists.txt b/libcxx/CMakeLists.txt
index 00fc9b3175158c5eb73ad3d866bb5c4645c0fd10..3c6bd0fbbd0d11a33d4f42d532ab87ab74d4ce93 100644 (file)
--- a/libcxx/CMakeLists.txt
+++ b/libcxx/CMakeLists.txt
@@ -623,6 +623,7 @@ function(cxx_add_warning_flags target)
     endif()
   elseif("${CMAKE_CXX_COMPILER_ID}" MATCHES "GNU")
     target_add_compile_flags_if_supported(${target} PRIVATE
+      -Wno-attributes
       -Wno-literal-suffix
       -Wno-c++14-compat
       -Wno-noexcept-type