third_party_nghttp2/cmake/ExtractValidFlags.cmake
Peter Wu dad222b8f4 cmake: fix jemalloc, libevent include dirs
Caught with cmake --warn-uninitialized.
2016-03-13 16:42:35 +01:00

32 lines
992 B
CMake

# Convenience function that checks the availability of certain
# C or C++ compiler flags and returns valid ones as a string.
include(CheckCCompilerFlag)
include(CheckCXXCompilerFlag)
function(extract_valid_c_flags varname)
set(valid_flags)
foreach(flag IN LISTS ARGN)
string(REGEX REPLACE "[^a-zA-Z0-9_]+" "_" flag_var ${flag})
set(flag_var "C_FLAG_${flag_var}")
check_c_compiler_flag("${flag}" "${flag_var}")
if(${flag_var})
set(valid_flags "${valid_flags} ${flag}")
endif()
endforeach()
set(${varname} "${valid_flags}" PARENT_SCOPE)
endfunction()
function(extract_valid_cxx_flags varname)
set(valid_flags)
foreach(flag IN LISTS ARGN)
string(REGEX REPLACE "[^a-zA-Z0-9_]+" "_" flag_var ${flag})
set(flag_var "CXX_FLAG_${flag_var}")
check_cxx_compiler_flag("${flag}" "${flag_var}")
if(${flag_var})
set(valid_flags "${valid_flags} ${flag}")
endif()
endforeach()
set(${varname} "${valid_flags}" PARENT_SCOPE)
endfunction()