[libcxx-commits] [libcxx] efae317 - [CMake] Unify llvm_check_linker_flag and llvm_check_compiler_linker_flag
Petr Hosek via libcxx-commits
libcxx-commits at lists.llvm.org
Tue Feb 21 20:25:11 PST 2023
Author: Petr Hosek
Date: 2023-02-22T04:24:49Z
New Revision: efae3174f09560353fb0f3d528bcbffe060d5438
URL: https://github.com/llvm/llvm-project/commit/efae3174f09560353fb0f3d528bcbffe060d5438
DIFF: https://github.com/llvm/llvm-project/commit/efae3174f09560353fb0f3d528bcbffe060d5438.diff
LOG: [CMake] Unify llvm_check_linker_flag and llvm_check_compiler_linker_flag
These have the same purposes but two different implementations.
llvm_check_compiler_linker_flag uses CMAKE_REQUIRED_FLAGS which affects
flags used both for compilation and linking which is problematic because
some flags may be link-only and trigger unused argument warning when set
during compilation. llvm_check_linker_flag does not have this issue so
we chose it as the prevailaing implementation.
Differential Revision: https://reviews.llvm.org/D143052
Added:
cmake/Modules/LLVMCheckLinkerFlag.cmake
Modified:
compiler-rt/cmake/config-ix.cmake
libcxx/cmake/config-ix.cmake
libunwind/cmake/config-ix.cmake
runtimes/CMakeLists.txt
Removed:
cmake/Modules/LLVMCheckCompilerLinkerFlag.cmake
llvm/cmake/modules/LLVMCheckLinkerFlag.cmake
################################################################################
diff --git a/cmake/Modules/LLVMCheckCompilerLinkerFlag.cmake b/cmake/Modules/LLVMCheckCompilerLinkerFlag.cmake
deleted file mode 100644
index f61ec0585f9a4..0000000000000
--- a/cmake/Modules/LLVMCheckCompilerLinkerFlag.cmake
+++ /dev/null
@@ -1,35 +0,0 @@
-include(CMakePushCheckState)
-
-include(CheckCompilerFlag OPTIONAL)
-
-if(NOT COMMAND check_compiler_flag)
- include(CheckCCompilerFlag)
- include(CheckCXXCompilerFlag)
-endif()
-
-function(llvm_check_compiler_linker_flag lang flag out_var)
- # If testing a flag with check_c_compiler_flag, it gets added to the compile
- # command only, but not to the linker command in that test. If the flag
- # is vital for linking to succeed, the test would fail even if it would
- # have succeeded if it was included on both commands.
- #
- # Therefore, try adding the flag to CMAKE_REQUIRED_FLAGS, which gets
- # added to both compiling and linking commands in the tests.
-
- cmake_push_check_state()
- set(CMAKE_REQUIRED_FLAGS "${CMAKE_REQUIRED_FLAGS} ${flag}")
- if(COMMAND check_compiler_flag)
- check_compiler_flag("${lang}" "" ${out_var})
- else()
- # Until the minimum CMAKE version is 3.19
- # cmake builtin compatible, except we assume lang is C or CXX
- if("${lang}" STREQUAL "C")
- check_c_compiler_flag("" ${out_var})
- elseif("${lang}" STREQUAL "CXX")
- check_cxx_compiler_flag("" ${out_var})
- else()
- message(FATAL_ERROR "\"${lang}\" is not C or CXX")
- endif()
- endif()
- cmake_pop_check_state()
-endfunction()
diff --git a/llvm/cmake/modules/LLVMCheckLinkerFlag.cmake b/cmake/Modules/LLVMCheckLinkerFlag.cmake
similarity index 100%
rename from llvm/cmake/modules/LLVMCheckLinkerFlag.cmake
rename to cmake/Modules/LLVMCheckLinkerFlag.cmake
diff --git a/compiler-rt/cmake/config-ix.cmake b/compiler-rt/cmake/config-ix.cmake
index 5f51befc1973f..f029a1ff57869 100644
--- a/compiler-rt/cmake/config-ix.cmake
+++ b/compiler-rt/cmake/config-ix.cmake
@@ -1,10 +1,10 @@
include(CMakePushCheckState)
-include(LLVMCheckCompilerLinkerFlag)
+include(LLVMCheckLinkerFlag)
include(CheckCCompilerFlag)
include(CheckCXXCompilerFlag)
include(CheckIncludeFiles)
include(CheckLibraryExists)
-include(LLVMCheckCompilerLinkerFlag)
+include(LLVMCheckLinkerFlag)
include(CheckSymbolExists)
include(TestBigEndian)
@@ -15,7 +15,7 @@ include(TestBigEndian)
# libunwind (and the compiler implicit -lunwind wouldn't succeed as the newly
# built libunwind isn't installed yet). For those cases, it'd be good to
# link with --uwnindlib=none. Check if that option works.
-llvm_check_compiler_linker_flag(C "--unwindlib=none" CXX_SUPPORTS_UNWINDLIB_NONE_FLAG)
+llvm_check_linker_flag(C "--unwindlib=none" CXX_SUPPORTS_UNWINDLIB_NONE_FLAG)
check_library_exists(c fopen "" COMPILER_RT_HAS_LIBC)
if (COMPILER_RT_USE_BUILTINS_LIBRARY)
@@ -195,12 +195,12 @@ check_library_exists(c++ __cxa_throw "" COMPILER_RT_HAS_LIBCXX)
check_library_exists(stdc++ __cxa_throw "" COMPILER_RT_HAS_LIBSTDCXX)
# Linker flags.
-llvm_check_compiler_linker_flag(C "-Wl,-z,text" COMPILER_RT_HAS_Z_TEXT)
-llvm_check_compiler_linker_flag(C "-fuse-ld=lld" COMPILER_RT_HAS_FUSE_LD_LLD_FLAG)
+llvm_check_linker_flag(C "-Wl,-z,text" COMPILER_RT_HAS_Z_TEXT)
+llvm_check_linker_flag(C "-fuse-ld=lld" COMPILER_RT_HAS_FUSE_LD_LLD_FLAG)
if(${CMAKE_SYSTEM_NAME} MATCHES "SunOS")
set(VERS_COMPAT_OPTION "-Wl,-z,gnu-version-script-compat")
- llvm_check_compiler_linker_flag(C "${VERS_COMPAT_OPTION}" COMPILER_RT_HAS_GNU_VERSION_SCRIPT_COMPAT)
+ llvm_check_linker_flag(C "${VERS_COMPAT_OPTION}" COMPILER_RT_HAS_GNU_VERSION_SCRIPT_COMPAT)
endif()
set(DUMMY_VERS ${CMAKE_BINARY_DIR}${CMAKE_FILES_DIRECTORY}/CMakeTmp/dummy.vers)
@@ -211,10 +211,10 @@ if(COMPILER_RT_HAS_GNU_VERSION_SCRIPT_COMPAT)
# -z gnu-version-script-compat.
string(APPEND VERS_OPTION " ${VERS_COMPAT_OPTION}")
endif()
-llvm_check_compiler_linker_flag(C "${VERS_OPTION}" COMPILER_RT_HAS_VERSION_SCRIPT)
+llvm_check_linker_flag(C "${VERS_OPTION}" COMPILER_RT_HAS_VERSION_SCRIPT)
if(ANDROID)
- llvm_check_compiler_linker_flag(C "-Wl,-z,global" COMPILER_RT_HAS_Z_GLOBAL)
+ llvm_check_linker_flag(C "-Wl,-z,global" COMPILER_RT_HAS_Z_GLOBAL)
check_library_exists(log __android_log_write "" COMPILER_RT_HAS_LIBLOG)
endif()
@@ -478,7 +478,7 @@ if(APPLE)
-lc++
-lc++abi)
- llvm_check_compiler_linker_flag(C "-fapplication-extension" COMPILER_RT_HAS_APP_EXTENSION)
+ llvm_check_linker_flag(C "-fapplication-extension" COMPILER_RT_HAS_APP_EXTENSION)
if(COMPILER_RT_HAS_APP_EXTENSION)
list(APPEND DARWIN_COMMON_LINK_FLAGS "-fapplication-extension")
endif()
diff --git a/libcxx/cmake/config-ix.cmake b/libcxx/cmake/config-ix.cmake
index 3bae536436835..ffc17dff74121 100644
--- a/libcxx/cmake/config-ix.cmake
+++ b/libcxx/cmake/config-ix.cmake
@@ -1,6 +1,6 @@
include(CMakePushCheckState)
include(CheckLibraryExists)
-include(LLVMCheckCompilerLinkerFlag)
+include(LLVMCheckLinkerFlag)
include(CheckCCompilerFlag)
include(CheckCXXCompilerFlag)
include(CheckCSourceCompiles)
@@ -12,7 +12,7 @@ include(CheckCSourceCompiles)
# libunwind (and the compiler implicit -lunwind wouldn't succeed as the newly
# built libunwind isn't installed yet). For those cases, it'd be good to
# link with --uwnindlib=none. Check if that option works.
-llvm_check_compiler_linker_flag(C "--unwindlib=none" CXX_SUPPORTS_UNWINDLIB_EQ_NONE_FLAG)
+llvm_check_linker_flag(C "--unwindlib=none" CXX_SUPPORTS_UNWINDLIB_EQ_NONE_FLAG)
if(WIN32 AND NOT MINGW)
# NOTE(compnerd) this is technically a lie, there is msvcrt, but for now, lets
diff --git a/libunwind/cmake/config-ix.cmake b/libunwind/cmake/config-ix.cmake
index d311477f02c69..ae6caebff3dc2 100644
--- a/libunwind/cmake/config-ix.cmake
+++ b/libunwind/cmake/config-ix.cmake
@@ -2,14 +2,14 @@ include(CMakePushCheckState)
include(CheckCCompilerFlag)
include(CheckCXXCompilerFlag)
include(CheckLibraryExists)
-include(LLVMCheckCompilerLinkerFlag)
+include(LLVMCheckLinkerFlag)
include(CheckSymbolExists)
include(CheckCSourceCompiles)
# The compiler driver may be implicitly trying to link against libunwind, which
# might not work if libunwind doesn't exist yet. Try to check if
# --unwindlib=none is supported, and use that if possible.
-llvm_check_compiler_linker_flag(C "--unwindlib=none" CXX_SUPPORTS_UNWINDLIB_EQ_NONE_FLAG)
+llvm_check_linker_flag(C "--unwindlib=none" CXX_SUPPORTS_UNWINDLIB_EQ_NONE_FLAG)
check_library_exists(c fopen "" LIBUNWIND_HAS_C_LIB)
@@ -31,11 +31,11 @@ endif()
# required for the link to go through. We remove sanitizers from the
# configuration checks to avoid spurious link errors.
-llvm_check_compiler_linker_flag(CXX "-nostdlib++" CXX_SUPPORTS_NOSTDLIBXX_FLAG)
+llvm_check_linker_flag(CXX "-nostdlib++" CXX_SUPPORTS_NOSTDLIBXX_FLAG)
if (CXX_SUPPORTS_NOSTDLIBXX_FLAG)
set(CMAKE_REQUIRED_FLAGS "${CMAKE_REQUIRED_FLAGS} -nostdlib++")
else()
- llvm_check_compiler_linker_flag(C "-nodefaultlibs" C_SUPPORTS_NODEFAULTLIBS_FLAG)
+ llvm_check_linker_flag(C "-nodefaultlibs" C_SUPPORTS_NODEFAULTLIBS_FLAG)
if (C_SUPPORTS_NODEFAULTLIBS_FLAG)
set(CMAKE_REQUIRED_FLAGS "${CMAKE_REQUIRED_FLAGS} -nodefaultlibs")
endif()
diff --git a/runtimes/CMakeLists.txt b/runtimes/CMakeLists.txt
index 50f782205ab48..74d540f3fb1e5 100644
--- a/runtimes/CMakeLists.txt
+++ b/runtimes/CMakeLists.txt
@@ -78,7 +78,7 @@ set(LLVM_CMAKE_DIR ${LLVM_MAIN_SRC_DIR}/cmake/modules)
set(LLVM_PATH ${CMAKE_CURRENT_SOURCE_DIR}/../llvm)
include(CheckLibraryExists)
-include(LLVMCheckCompilerLinkerFlag)
+include(LLVMCheckLinkerFlag)
include(CheckCCompilerFlag)
include(CheckCXXCompilerFlag)
@@ -110,7 +110,7 @@ if (NOT LLVM_RUNTIMES_LINKING_WORKS)
# --unwindlib=none is supported, and use that if possible.
# Don't add this if not necessary to fix linking, as it can break using
# e.g. ASAN/TSAN.
- llvm_check_compiler_linker_flag(C "--unwindlib=none" CXX_SUPPORTS_UNWINDLIB_EQ_NONE_FLAG)
+ llvm_check_linker_flag(C "--unwindlib=none" CXX_SUPPORTS_UNWINDLIB_EQ_NONE_FLAG)
if (CXX_SUPPORTS_UNWINDLIB_EQ_NONE_FLAG)
set(ORIG_CMAKE_REQUIRED_FLAGS "${CMAKE_REQUIRED_FLAGS}")
set(CMAKE_REQUIRED_FLAGS "${CMAKE_REQUIRED_FLAGS} --unwindlib=none")
@@ -140,7 +140,7 @@ endif()
# Check for -nostdlib++ first; if there's no C++ standard library yet,
# all check_cxx_compiler_flag commands will fail until we add -nostdlib++
# (or -nodefaultlibs).
-llvm_check_compiler_linker_flag(CXX "-nostdlib++" CXX_SUPPORTS_NOSTDLIBXX_FLAG)
+llvm_check_linker_flag(CXX "-nostdlib++" CXX_SUPPORTS_NOSTDLIBXX_FLAG)
if (CXX_SUPPORTS_NOSTDLIBXX_FLAG)
set(CMAKE_REQUIRED_FLAGS "${CMAKE_REQUIRED_FLAGS} -nostdlib++")
endif()
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