[runtimes] remove workaround for old CMake when setting --unwindlib=none

cmake/Modules/LLVMCheckCompilerLinkerFlag.cmake

@@ -1,7 +1,7 @@
 include(CMakePushCheckState)
 include(CheckCompilerFlag)
 
-function(llvm_check_compiler_linker_flag lang flag out_var)
+function(llvm_check_compiler_linker_flag lang reset target_type flag out_var)
   # If testing a flag with check_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
@@ -10,8 +10,32 @@ function(llvm_check_compiler_linker_flag lang flag out_var)
   # 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()
+  # In some cases, we need to disable existing linker options completely;
+  # e.g. due to https://gitlab.kitware.com/cmake/cmake/-/issues/23454, in the
+  # context of CXX_SUPPORTS_UNWINDLIB_EQ_NONE_FLAG, for example. To this end,
+  # we the RESET option of cmake_push_check_state, c.f.
+  # https://cmake.org/cmake/help/latest/module/CMakePushCheckState.html
+  #
+  # Due to the same CMake issue, we need to be able to override the targe type,
+  # as some checks will fail by default for shared libraries. A concrete example
+  # is checking for `-funwind-tables` when building libunwind (e.g. for ARM EHABI).
+  #
+  # This happens because, when performing CMake checks, adding `-funwind-tables`
+  # for a dynamic target causes the check to produce a false negative, because the
+  # compiler compiler generates calls to `__aeabi_unwind_cpp_pr0`, which is defined
+  # in libunwind itself, which isn't built yet, so the linker complains about
+  # undefined symbols. This would lead to libunwind not being built with this flag,
+  # which makes libunwind quite useless in this setup.
+  cmake_push_check_state(${reset})
   set(CMAKE_REQUIRED_FLAGS "${CMAKE_REQUIRED_FLAGS} ${flag}")
+  if (NOT target_type STREQUAL "")
+    set(_previous_CMAKE_TRY_COMPILE_TARGET_TYPE ${CMAKE_TRY_COMPILE_TARGET_TYPE})
+    set(CMAKE_TRY_COMPILE_TARGET_TYPE STATIC_LIBRARY)
+  endif()
+  # run the actual check
   check_compiler_flag("${lang}" "" ${out_var})
+  if (NOT target_type STREQUAL "")
+    set(CMAKE_TRY_COMPILE_TARGET_TYPE ${_previous_CMAKE_TRY_COMPILE_TARGET_TYPE})
+  endif()
   cmake_pop_check_state()
 endfunction()

compiler-rt/cmake/config-ix.cmake

@@ -4,8 +4,8 @@ include(CheckCCompilerFlag)
 include(CheckCXXCompilerFlag)
 include(CheckIncludeFiles)
 include(CheckLibraryExists)
-include(LLVMCheckCompilerLinkerFlag)
 include(CheckSymbolExists)
+include(LLVMCheckCompilerLinkerFlag)
 include(TestBigEndian)
 
 # The compiler driver may be implicitly trying to link against libunwind.
@@ -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 --unwindlib=none. Check if that option works.
-llvm_check_compiler_linker_flag(C "--unwindlib=none" CXX_SUPPORTS_UNWINDLIB_NONE_FLAG)
+llvm_check_compiler_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)
@@ -190,12 +190,13 @@ 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_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)
 
 if(${CMAKE_SYSTEM_NAME} MATCHES "SunOS" AND LLVM_LINKER_IS_SOLARISLD)
   set(VERS_COMPAT_OPTION "-Wl,-z,gnu-version-script-compat")
-  llvm_check_compiler_linker_flag(C "${VERS_COMPAT_OPTION}" COMPILER_RT_HAS_GNU_VERSION_SCRIPT_COMPAT)
+  llvm_check_compiler_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)
@@ -206,10 +207,10 @@ 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_compiler_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_compiler_linker_flag(C "-Wl,-z,global" "" "" COMPILER_RT_HAS_Z_GLOBAL)
   check_library_exists(log __android_log_write "" COMPILER_RT_HAS_LIBLOG)
 endif()
 
@@ -494,7 +495,8 @@ if(APPLE)
     -lc++
     -lc++abi)
 
-  llvm_check_compiler_linker_flag(C "-fapplication-extension" COMPILER_RT_HAS_APP_EXTENSION)
+  llvm_check_compiler_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()

libcxx/cmake/Modules/HandleLibcxxFlags.cmake

@@ -6,6 +6,7 @@
 
 include(CheckCXXCompilerFlag)
 include(HandleFlags)
+include(LLVMCheckCompilerLinkerFlag)
 
 unset(add_flag_if_supported)
 
@@ -31,7 +32,8 @@ endmacro()
 macro(add_flags_if_supported)
   foreach(flag ${ARGN})
       mangle_name("${flag}" flagname)
-      check_cxx_compiler_flag("${flag}" "CXX_SUPPORTS_${flagname}_FLAG")
+      llvm_check_compiler_linker_flag(
+          CXX "${flag}" RESET STATIC_LIBRARY "CXX_SUPPORTS_${flagname}_FLAG")
       add_flags_if(CXX_SUPPORTS_${flagname}_FLAG ${flag})
   endforeach()
 endmacro()

libcxx/cmake/config-ix.cmake

@@ -1,10 +1,10 @@
 include(CMakePushCheckState)
 include(CheckLibraryExists)
 include(CheckSymbolExists)
-include(LLVMCheckCompilerLinkerFlag)
 include(CheckCCompilerFlag)
 include(CheckCXXCompilerFlag)
 include(CheckCSourceCompiles)
+include(LLVMCheckCompilerLinkerFlag)
 
 # The compiler driver may be implicitly trying to link against libunwind.
 # This is normally ok (libcxx relies on an unwinder), but if libunwind is
@@ -13,7 +13,8 @@ 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 --unwindlib=none. Check if that option works.
-llvm_check_compiler_linker_flag(C "--unwindlib=none" CXX_SUPPORTS_UNWINDLIB_EQ_NONE_FLAG)
+llvm_check_compiler_linker_flag(
+    C "--unwindlib=none" RESET STATIC_LIBRARY CXX_SUPPORTS_UNWINDLIB_EQ_NONE_FLAG)
 
 if (NOT LIBCXX_USE_COMPILER_RT)
   if(WIN32 AND NOT MINGW)
@@ -27,8 +28,10 @@ if (NOT LIBCXX_USE_COMPILER_RT)
   endif()
 endif()
 
-check_cxx_compiler_flag(-nostdlibinc CXX_SUPPORTS_NOSTDLIBINC_FLAG)
-check_cxx_compiler_flag(-nolibc CXX_SUPPORTS_NOLIBC_FLAG)
+llvm_check_compiler_linker_flag(
+    CXX "-nostdlibinc" RESET STATIC_LIBRARY CXX_SUPPORTS_NOSTDLIBINC_FLAG)
+llvm_check_compiler_linker_flag(
+    CXX "-nolibc" RESET STATIC_LIBRARY CXX_SUPPORTS_NOLIBC_FLAG)
 
 # libc++ is using -nostdlib++ at the link step when available,
 # otherwise -nodefaultlibs is used. We want all our checks to also
@@ -39,11 +42,13 @@ check_cxx_compiler_flag(-nolibc CXX_SUPPORTS_NOLIBC_FLAG)
 # required for the link to go through. We remove sanitizers from the
 # configuration checks to avoid spurious link errors.
 
-check_cxx_compiler_flag(-nostdlib++ CXX_SUPPORTS_NOSTDLIBXX_FLAG)
+llvm_check_compiler_linker_flag(
+    CXX "-nostdlib++" RESET STATIC_LIBRARY CXX_SUPPORTS_NOSTDLIBXX_FLAG)
 if (CXX_SUPPORTS_NOSTDLIBXX_FLAG)
   set(CMAKE_REQUIRED_FLAGS "${CMAKE_REQUIRED_FLAGS} -nostdlib++")
 else()
-  check_c_compiler_flag(-nodefaultlibs C_SUPPORTS_NODEFAULTLIBS_FLAG)
+  llvm_check_compiler_linker_flag(
+      C "-nodefaultlibs" RESET STATIC_LIBRARY C_SUPPORTS_NODEFAULTLIBS_FLAG)
   if (C_SUPPORTS_NODEFAULTLIBS_FLAG)
     set(CMAKE_REQUIRED_FLAGS "${CMAKE_REQUIRED_FLAGS} -nodefaultlibs")
   endif()

libcxxabi/cmake/Modules/HandleLibcxxabiFlags.cmake

@@ -6,6 +6,7 @@
 
 include(CheckCXXCompilerFlag)
 include(HandleFlags)
+include(LLVMCheckCompilerLinkerFlag)
 
 unset(add_flag_if_supported)
 
@@ -31,7 +32,8 @@ endmacro()
 macro(add_flags_if_supported)
   foreach(flag ${ARGN})
       mangle_name("${flag}" flagname)
-      check_cxx_compiler_flag("${flag}" "CXX_SUPPORTS_${flagname}_FLAG")
+      llvm_check_compiler_linker_flag(
+          CXX "${flag}" RESET STATIC_LIBRARY "CXX_SUPPORTS_${flagname}_FLAG")
       add_flags_if(CXX_SUPPORTS_${flagname}_FLAG ${flag})
   endforeach()
 endmacro()

libcxxabi/cmake/config-ix.cmake

@@ -3,6 +3,7 @@ include(CheckLibraryExists)
 include(CheckCCompilerFlag)
 include(CheckCXXCompilerFlag)
 include(CheckCSourceCompiles)
+include(LLVMCheckCompilerLinkerFlag)
 
 check_library_exists(c fopen "" LIBCXXABI_HAS_C_LIB)
 if (NOT LIBCXXABI_USE_COMPILER_RT)
@@ -23,11 +24,13 @@ endif ()
 # required for the link to go through. We remove sanitizers from the
 # configuration checks to avoid spurious link errors.
 
-check_cxx_compiler_flag(-nostdlib++ CXX_SUPPORTS_NOSTDLIBXX_FLAG)
+llvm_check_compiler_linker_flag(
+    CXX "-nostdlib++" RESET STATIC_LIBRARY CXX_SUPPORTS_NOSTDLIBXX_FLAG)
 if (CXX_SUPPORTS_NOSTDLIBXX_FLAG)
   set(CMAKE_REQUIRED_FLAGS "${CMAKE_REQUIRED_FLAGS} -nostdlib++")
 else()
-  check_c_compiler_flag(-nodefaultlibs C_SUPPORTS_NODEFAULTLIBS_FLAG)
+  llvm_check_compiler_linker_flag(
+      C "-nodefaultlibs" RESET STATIC_LIBRARY C_SUPPORTS_NODEFAULTLIBS_FLAG)
   if (C_SUPPORTS_NODEFAULTLIBS_FLAG)
     set(CMAKE_REQUIRED_FLAGS "${CMAKE_REQUIRED_FLAGS} -nodefaultlibs")
   endif()
@@ -92,7 +95,8 @@ int main(void) { return 0; }
 endif()
 
 # Check compiler flags
-check_cxx_compiler_flag(-nostdinc++ CXX_SUPPORTS_NOSTDINCXX_FLAG)
+llvm_check_compiler_linker_flag(
+    CXX "-nostdinc++" RESET STATIC_LIBRARY CXX_SUPPORTS_NOSTDINCXX_FLAG)
 
 # Check libraries
 if(FUCHSIA)

libunwind/CMakeLists.txt

@@ -215,23 +215,7 @@ endif()
 add_cxx_compile_flags_if_supported(-fstrict-aliasing)
 add_cxx_compile_flags_if_supported(-EHsc)
 
-# Don't run the linker in this CMake check.
-#
-# The reason why this was added is that when building libunwind for
-# ARM Linux, we need to pass the -funwind-tables flag in order for it to
-# work properly with ARM EHABI.
-#
-# However, when performing CMake checks, adding this flag causes the check
-# to produce a false negative, because the compiler generates calls
-# to __aeabi_unwind_cpp_pr0, which is defined in libunwind itself,
-# which isn't built yet, so the linker complains about undefined symbols.
-#
-# This leads to libunwind not being built with this flag, which makes
-# libunwind quite useless in this setup.
-set(_previous_CMAKE_TRY_COMPILE_TARGET_TYPE ${CMAKE_TRY_COMPILE_TARGET_TYPE})
-set(CMAKE_TRY_COMPILE_TARGET_TYPE STATIC_LIBRARY)
 add_compile_flags_if_supported(-funwind-tables)
-set(CMAKE_TRY_COMPILE_TARGET_TYPE ${_previous_CMAKE_TRY_COMPILE_TARGET_TYPE})
 
 if (LIBUNWIND_USES_ARM_EHABI AND NOT CXX_SUPPORTS_FUNWIND_TABLES_FLAG)
   message(SEND_ERROR "The -funwind-tables flag must be supported "

libunwind/cmake/Modules/HandleLibunwindFlags.cmake

@@ -7,6 +7,7 @@
 include(CheckCCompilerFlag)
 include(CheckCXXCompilerFlag)
 include(HandleFlags)
+include(LLVMCheckCompilerLinkerFlag)
 
 unset(add_flag_if_supported)
 
@@ -30,7 +31,8 @@ endmacro()
 macro(add_compile_flags_if_supported)
   foreach(flag ${ARGN})
       mangle_name("${flag}" flagname)
-      check_cxx_compiler_flag("${flag}" "CXX_SUPPORTS_${flagname}_FLAG")
+      llvm_check_compiler_linker_flag(
+          CXX "${flag}" RESET STATIC_LIBRARY "CXX_SUPPORTS_${flagname}_FLAG")
       add_compile_flags_if(CXX_SUPPORTS_${flagname}_FLAG ${flag})
   endforeach()
 endmacro()

libunwind/cmake/config-ix.cmake

@@ -9,7 +9,8 @@ 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_compiler_linker_flag(
+    C "--unwindlib=none" RESET STATIC_LIBRARY CXX_SUPPORTS_UNWINDLIB_EQ_NONE_FLAG)
 
 if (HAIKU)
   check_library_exists(root fopen "" LIBUNWIND_HAS_ROOT_LIB)
@@ -35,11 +36,13 @@ 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_compiler_linker_flag(
+    CXX "-nostdlib++" RESET STATIC_LIBRARY CXX_SUPPORTS_NOSTDLIBXX_FLAG)
 if (CXX_SUPPORTS_NOSTDLIBXX_FLAG)
   set(CMAKE_REQUIRED_FLAGS "${CMAKE_REQUIRED_FLAGS} -nostdlib++")
 else()
-  llvm_check_compiler_linker_flag(C "-nodefaultlibs" C_SUPPORTS_NODEFAULTLIBS_FLAG)
+  llvm_check_compiler_linker_flag(
+      C "-nodefaultlibs" RESET STATIC_LIBRARY C_SUPPORTS_NODEFAULTLIBS_FLAG)
   if (C_SUPPORTS_NODEFAULTLIBS_FLAG)
     set(CMAKE_REQUIRED_FLAGS "${CMAKE_REQUIRED_FLAGS} -nodefaultlibs")
   endif()

llvm/cmake/modules/HandleLLVMOptions.cmake

@@ -15,6 +15,7 @@ include(CheckCXXCompilerFlag)
 include(CheckCXXSourceCompiles)
 include(CheckSymbolExists)
 include(CMakeDependentOption)
+include(LLVMCheckCompilerLinkerFlag)
 include(LLVMProcessSources)
 
 if(CMAKE_LINKER MATCHES ".*lld" OR (LLVM_USE_LINKER STREQUAL "lld" OR LLVM_ENABLE_LLD))
@@ -333,9 +334,11 @@ function(append_if condition value)
 endfunction()
 
 macro(add_flag_if_supported flag name)
-  check_c_compiler_flag("-Werror ${flag}" "C_SUPPORTS_${name}")
+  llvm_check_compiler_linker_flag(
+      C "-Werror ${flag}" RESET STATIC_LIBRARY "C_SUPPORTS_${name}")
   append_if("C_SUPPORTS_${name}" "${flag}" CMAKE_C_FLAGS)
-  check_cxx_compiler_flag("-Werror ${flag}" "CXX_SUPPORTS_${name}")
+  llvm_check_compiler_linker_flag(
+      CXX "-Werror ${flag}" RESET STATIC_LIBRARY "CXX_SUPPORTS_${name}")
   append_if("CXX_SUPPORTS_${name}" "${flag}" CMAKE_CXX_FLAGS)
 endmacro()
 

offload/CMakeLists.txt

@@ -296,7 +296,9 @@ if(OPENMP_STANDALONE_BUILD OR TARGET omp)
   # Check LIBOMP_HAVE_VERSION_SCRIPT_FLAG
   include(LLVMCheckCompilerLinkerFlag)
   if(NOT APPLE)
-    llvm_check_compiler_linker_flag(C "-Wl,--version-script=${CMAKE_CURRENT_LIST_DIR}/../openmp/runtime/src/exports_test_so.txt" LIBOMP_HAVE_VERSION_SCRIPT_FLAG)
+    llvm_check_compiler_linker_flag(C
+        "-Wl,--version-script=${CMAKE_CURRENT_LIST_DIR}/../openmp/runtime/src/exports_test_so.txt"
+        "" "" LIBOMP_HAVE_VERSION_SCRIPT_FLAG)
   endif()
 endif()
 

openmp/runtime/cmake/config-ix.cmake

@@ -128,13 +128,15 @@ check_symbol_exists(_aligned_malloc "malloc.h" LIBOMP_HAVE__ALIGNED_MALLOC)
 
 # Check linker flags
 if(WIN32)
-  llvm_check_compiler_linker_flag(C /SAFESEH LIBOMP_HAVE_SAFESEH_FLAG)
+  llvm_check_compiler_linker_flag(C "/SAFESEH" "" "" LIBOMP_HAVE_SAFESEH_FLAG)
 elseif(NOT APPLE)
-  llvm_check_compiler_linker_flag(C -Wl,-x LIBOMP_HAVE_X_FLAG)
-  llvm_check_compiler_linker_flag(C -Wl,--as-needed LIBOMP_HAVE_AS_NEEDED_FLAG)
-  llvm_check_compiler_linker_flag(C "-Wl,--version-script=${LIBOMP_SRC_DIR}/exports_test_so.txt" LIBOMP_HAVE_VERSION_SCRIPT_FLAG)
-  llvm_check_compiler_linker_flag(C -static-libgcc LIBOMP_HAVE_STATIC_LIBGCC_FLAG)
-  llvm_check_compiler_linker_flag(C -Wl,-z,noexecstack LIBOMP_HAVE_Z_NOEXECSTACK_FLAG)
+  llvm_check_compiler_linker_flag(C "-Wl,-x" "" "" LIBOMP_HAVE_X_FLAG)
+  llvm_check_compiler_linker_flag(C "-Wl,--as-needed" "" ""  LIBOMP_HAVE_AS_NEEDED_FLAG)
+  llvm_check_compiler_linker_flag(C
+    "-Wl,--version-script=${LIBOMP_SRC_DIR}/exports_test_so.txt"
+    "" "" LIBOMP_HAVE_VERSION_SCRIPT_FLAG)
+  llvm_check_compiler_linker_flag(C "-static-libgcc" "" "" LIBOMP_HAVE_STATIC_LIBGCC_FLAG)
+  llvm_check_compiler_linker_flag(C "-Wl,-z,noexecstack" "" "" LIBOMP_HAVE_Z_NOEXECSTACK_FLAG)
 endif()
 
 # Check Intel(R) C Compiler specific flags
@@ -145,8 +147,8 @@ if(CMAKE_C_COMPILER_ID STREQUAL "Intel" OR CMAKE_C_COMPILER_ID STREQUAL "IntelLL
   check_cxx_compiler_flag(-Qoption,cpp,--extended_float_types LIBOMP_HAVE_EXTENDED_FLOAT_TYPES_FLAG)
   check_cxx_compiler_flag(-falign-stack=maintain-16-byte LIBOMP_HAVE_FALIGN_STACK_FLAG)
   check_cxx_compiler_flag("-opt-streaming-stores never" LIBOMP_HAVE_OPT_STREAMING_STORES_FLAG)
-  llvm_check_compiler_linker_flag(C -static-intel LIBOMP_HAVE_STATIC_INTEL_FLAG)
-  llvm_check_compiler_linker_flag(C -no-intel-extensions LIBOMP_HAVE_NO_INTEL_EXTENSIONS_FLAG)
+  llvm_check_compiler_linker_flag(C "-static-intel" "" "" LIBOMP_HAVE_STATIC_INTEL_FLAG)
+  llvm_check_compiler_linker_flag(C "-no-intel-extensions" "" "" LIBOMP_HAVE_NO_INTEL_EXTENSIONS_FLAG)
   check_library_exists(irc_pic _intel_fast_memcpy "" LIBOMP_HAVE_IRC_PIC_LIBRARY)
 endif()