Index: cmake/config-ix.cmake =================================================================== --- cmake/config-ix.cmake +++ cmake/config-ix.cmake @@ -1,5 +1,26 @@ include(CheckLibraryExists) include(CheckCXXCompilerFlag) + +check_library_exists(c fopen "" LIBCXX_HAS_C_LIB) +check_library_exists(gcc_s __gcc_personality_v0 "" LIBCXX_HAS_GCC_S_LIB) + +# libc++ is built with -nodefaultlibs, so we want all our checks to also +# use this option, otherwise we may end up with an inconsistency between +# the flags we think we require during configuration (if the checks are +# performed without -nodefaultlibs) and the flags that are actually +# required during compilation (which has the -nodefaultlibs). libc is +# required for the link to go through. +check_cxx_compiler_flag(-nodefaultlibs LIBCXX_SUPPORTS_NODEFAULTLIBS_FLAG) +if (LIBCXX_SUPPORTS_NODEFAULTLIBS_FLAG) + list(APPEND CMAKE_REQUIRED_LIBRARIES -nodefaultlibs) + if (LIBCXX_HAS_C_LIB) + list(APPEND CMAKE_REQUIRED_LIBRARIES c) + endif () + if (LIBCXX_HAS_GCC_S_LIB) + list(APPEND CMAKE_REQUIRED_LIBRARIES gcc_s) + endif () +endif () + include(CheckLibcxxAtomic) # Check compiler flags @@ -14,7 +35,5 @@ # Check libraries check_library_exists(pthread pthread_create "" LIBCXX_HAS_PTHREAD_LIB) -check_library_exists(c fopen "" LIBCXX_HAS_C_LIB) check_library_exists(m ccos "" LIBCXX_HAS_M_LIB) check_library_exists(rt clock_gettime "" LIBCXX_HAS_RT_LIB) -check_library_exists(gcc_s __gcc_personality_v0 "" LIBCXX_HAS_GCC_S_LIB)