[cmake] Use lld as a first preference

Like Gold, it doesn't warn about sys_nerr, _sys_errlist, and co.
Unlike Gold, we can use this on all platforms. It's also faster than
both Gold and plain, old ld.
This commit is contained in:
Mahmoud Al-Qudsi 2020-10-26 18:17:53 -05:00
parent 4081d58577
commit 36ed66beda

View file

@ -55,13 +55,20 @@ set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wall -Wextra \
# Disable exception handling.
add_compile_options(-fno-exceptions)
# Prefer the gold linker because it doesn't emit useless warnings about sys_nerr and _sys_errlist.
if (UNIX AND NOT APPLE)
execute_process(COMMAND ${CMAKE_C_COMPILER} -fuse-ld=gold -Wl,--version
ERROR_QUIET OUTPUT_VARIABLE LD_VERSION)
if ("${LD_VERSION}" MATCHES "GNU gold")
set(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} -fuse-ld=gold")
endif()
# Prefer lld or the gold linker because they don't emit useless warnings about sys_nerr and
# _sys_errlist. They're also faster (significantly so in the case of lld).
if (UNIX)
execute_process(COMMAND ${CMAKE_C_COMPILER} -fuse-ld=lld -Wl,--version
ERROR_QUIET OUTPUT_VARIABLE LD_VERSION)
if ("${LD_VERSION}" MATCHES "LLD ")
set(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} -fuse-ld=lld")
elseif (NOT APPLE)
execute_process(COMMAND ${CMAKE_C_COMPILER} -fuse-ld=gold -Wl,--version
ERROR_QUIET OUTPUT_VARIABLE LD_VERSION)
if ("${LD_VERSION}" MATCHES "GNU gold")
set(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} -fuse-ld=gold")
endif()
endif()
endif()
# Hide the CMake Rules directories in Xcode projects.