[CMake] Don't override required compiler flags in the runtimes build
Ensure that HandleLLVMOptions adds all necessary required flags,
including -Wno-error when building with LLVM_ENABLE_WERROR enabled.
Differential Revision: https://reviews.llvm.org/D58092
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@353790 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/runtimes/CMakeLists.txt b/runtimes/CMakeLists.txt
index a6fe5e3..98f7f0c 100644
--- a/runtimes/CMakeLists.txt
+++ b/runtimes/CMakeLists.txt
@@ -93,23 +93,15 @@
set(LLVM_ENABLE_LIBCXX ON CACHE BOOL "")
endif()
- set(SAFE_CMAKE_REQUIRED_FLAGS ${CMAKE_REQUIRED_FLAGS})
- set(SAFE_CMAKE_REQUIRED_LIBRARIES ${CMAKE_REQUIRED_LIBRARIES})
-
include(CheckLibraryExists)
include(CheckCCompilerFlag)
- check_library_exists(c fopen "" LLVM_HAS_C_LIB)
- check_c_compiler_flag(-nodefaultlibs LLVM_HAS_NODEFAULTLIBS_FLAG)
- if(LLVM_HAS_NODEFAULTLIBS_FLAG)
- set(CMAKE_REQUIRED_FLAGS "${CMAKE_REQUIRED_FLAGS} -nodefaultlibs")
- if(LLVM_HAS_C_LIB)
- list(APPEND CMAKE_REQUIRED_LIBRARIES c)
- endif()
- endif()
+ # We don't have libc++ (yet).
+ set(CMAKE_REQUIRED_FLAGS "${CMAKE_REQUIRED_FLAGS} -nostdlib++")
# Avoid checking whether the compiler is working.
set(LLVM_COMPILER_CHECKED ON)
+ # Mark the compiler as compatible with GCC.
# Enable warnings, otherwise -w gets added to the cflags by HandleLLVMOptions
# resulting in unjustified successes by check_cxx_compiler_flag.
set(LLVM_ENABLE_WARNINGS ON)
@@ -119,8 +111,8 @@
include(HandleLLVMOptions)
include(FindPythonInterp)
- set(CMAKE_REQUIRED_FLAGS ${SAFE_CMAKE_REQUIRED_FLAGS})
- set(CMAKE_REQUIRED_LIBRARIES ${SAFE_CMAKE_REQUIRED_LIBRARIES})
+ # Remove the -nostdlib++ option we've added earlier.
+ string(REPLACE "-nostdlib++" "" CMAKE_REQUIRED_FLAGS "${CMAKE_REQUIRED_FLAGS}")
# This can be used to detect whether we're in the runtimes build.
set(RUNTIMES_BUILD ON)
