G M: Attached is a patch for libcxx's cmake file.
I've changed it so we don't set highest level warnings (all) for MSVC when building projects using cmake and instead leave the default. That's /W4 on my machine and seems to be ok.
With all warnings on for msvc, we see literally thousands of warnings. 99.99% aren't relevant and just obscure the ones that are.
I think the user can still override things if they want something different from the command line when using cmake.
git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@192010 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/CMakeLists.txt b/CMakeLists.txt
index 1d4375d..15b76d2 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -185,7 +185,9 @@
endmacro()
# Get warning flags
-append_if(LIBCXX_CXX_WARNING_FLAGS LIBCXX_HAS_WALL_FLAG -Wall)
+if (NOT MSVC)
+ append_if(LIBCXX_CXX_WARNING_FLAGS LIBCXX_HAS_WALL_FLAG -Wall)
+endif()
append_if(LIBCXX_CXX_WARNING_FLAGS LIBCXX_HAS_W_FLAG -W)
append_if(LIBCXX_CXX_WARNING_FLAGS LIBCXX_HAS_WNO_UNUSED_PARAMETER_FLAG -Wno-unused-parameter)
append_if(LIBCXX_CXX_WARNING_FLAGS LIBCXX_HAS_WWRITE_STRINGS_FLAG -Wwrite-strings)