[cmake] also do static-vs-linker work-around in runtimes/CMakeLists.txt

Author: h-vetinari

runtimes/CMakeLists.txt

@@ -104,6 +104,17 @@ filter_prefixed("${CMAKE_C_IMPLICIT_INCLUDE_DIRECTORIES}" ${LLVM_BINARY_DIR} CMA
 filter_prefixed("${CMAKE_CXX_IMPLICIT_INCLUDE_DIRECTORIES}" ${LLVM_BINARY_DIR} CMAKE_CXX_IMPLICIT_INCLUDE_DIRECTORIES)
 filter_prefixed("${CMAKE_ASM_IMPLICIT_INCLUDE_DIRECTORIES}" ${LLVM_BINARY_DIR} CMAKE_ASM_IMPLICIT_INCLUDE_DIRECTORIES)
 
+# Disable linker for CMake flag compatibility checks
+#
+# Due to https://gitlab.kitware.com/cmake/cmake/-/issues/23454, we need to
+# disable CMAKE_REQUIRED_LINK_OPTIONS (c.f. CXX_SUPPORTS_UNWINDLIB_EQ_NONE_FLAG),
+# for static targets; cache the target type here, and reset it after the various
+# checks have been performed.
+set(_previous_CMAKE_TRY_COMPILE_TARGET_TYPE ${CMAKE_TRY_COMPILE_TARGET_TYPE})
+set(_previous_CMAKE_REQUIRED_LINK_OPTIONS ${CMAKE_REQUIRED_LINK_OPTIONS})
+set(CMAKE_TRY_COMPILE_TARGET_TYPE STATIC_LIBRARY)
+set(CMAKE_REQUIRED_LINK_OPTIONS)
+
 # The compiler driver may be implicitly trying to link against libunwind,
 # which might not work if libunwind doesn't exist yet. Try to check if
 # --unwindlib=none is supported, and use that if possible.
@@ -132,6 +143,10 @@ if (CXX_SUPPORTS_NOSTDINCXX_FLAG)
   set(CMAKE_REQUIRED_FLAGS "${CMAKE_REQUIRED_FLAGS} -nostdinc++")
 endif()
 
+# reset CMAKE_TRY_COMPILE_TARGET_TYPE & CMAKE_REQUIRED_LINK_OPTIONS after flag checks
+set(CMAKE_TRY_COMPILE_TARGET_TYPE ${_previous_CMAKE_TRY_COMPILE_TARGET_TYPE})
+set(CMAKE_REQUIRED_LINK_OPTIONS ${_previous_CMAKE_REQUIRED_LINK_OPTIONS})
+
 # Avoid checking whether the compiler is working.
 set(LLVM_COMPILER_CHECKED ON)