Performing C SOURCE FILE Test CMAKE_HAVE_LIBC_PTHREAD failed with the following output: Change Dir: /var/tmp/portage/net-libs/google-cloud-cpp-0.10.0-r1/work/google-cloud-cpp-0.10.0_build/CMakeFiles/CMakeTmp Run Build Command(s):/usr/bin/gmake cmTC_ea2c0/fast && /usr/bin/gmake -f CMakeFiles/cmTC_ea2c0.dir/build.make CMakeFiles/cmTC_ea2c0.dir/build gmake[1]: Entering directory '/var/tmp/portage/net-libs/google-cloud-cpp-0.10.0-r1/work/google-cloud-cpp-0.10.0_build/CMakeFiles/CMakeTmp' Building C object CMakeFiles/cmTC_ea2c0.dir/src.c.o /usr/lib/llvm/10/bin/x86_64-pc-linux-gnu-clang -DNDEBUG -O2 -pipe -march=native -frecord-gcc-switches -fno-diagnostics-color -DCMAKE_HAVE_LIBC_PTHREAD -o CMakeFiles/cmTC_ea2c0.dir/src.c.o -c /var/tmp/portage/net-libs/google-cloud-cpp-0.10.0-r1/work/google-cloud-cpp-0.10.0_build/CMakeFiles/CMakeTmp/src.c Linking C executable cmTC_ea2c0 /usr/bin/cmake -E cmake_link_script CMakeFiles/cmTC_ea2c0.dir/link.txt --verbose=1 /usr/lib/llvm/10/bin/x86_64-pc-linux-gnu-clang -O2 -pipe -march=native -frecord-gcc-switches -fno-diagnostics-color -DCMAKE_HAVE_LIBC_PTHREAD -Wl,-O1 -Wl,--as-needed -Wl,--defsym=__gentoo_check_ldflags__=0 -fuse-ld=lld CMakeFiles/cmTC_ea2c0.dir/src.c.o -o cmTC_ea2c0 ld.lld: error: undefined symbol: pthread_create >>> referenced by src.c >>> CMakeFiles/cmTC_ea2c0.dir/src.c.o:(main) ld.lld: error: undefined symbol: pthread_detach >>> referenced by src.c >>> CMakeFiles/cmTC_ea2c0.dir/src.c.o:(main) ld.lld: error: undefined symbol: pthread_cancel >>> referenced by src.c >>> CMakeFiles/cmTC_ea2c0.dir/src.c.o:(main) ld.lld: error: undefined symbol: pthread_join >>> referenced by src.c >>> CMakeFiles/cmTC_ea2c0.dir/src.c.o:(main) clang-10: error: linker command failed with exit code 1 (use -v to see invocation) gmake[1]: *** [CMakeFiles/cmTC_ea2c0.dir/build.make:106: cmTC_ea2c0] Error 1 gmake[1]: Leaving directory '/var/tmp/portage/net-libs/google-cloud-cpp-0.10.0-r1/work/google-cloud-cpp-0.10.0_build/CMakeFiles/CMakeTmp' gmake: *** [Makefile:140: cmTC_ea2c0/fast] Error 2 Source file was: #include void* test_func(void* data) { return data; } int main(void) { pthread_t thread; pthread_create(&thread, NULL, test_func, NULL); pthread_detach(thread); pthread_cancel(thread); pthread_join(thread, NULL); pthread_atfork(NULL, NULL, NULL); pthread_exit(NULL); return 0; } Determining if the function pthread_create exists in the pthreads failed with the following output: Change Dir: /var/tmp/portage/net-libs/google-cloud-cpp-0.10.0-r1/work/google-cloud-cpp-0.10.0_build/CMakeFiles/CMakeTmp Run Build Command(s):/usr/bin/gmake cmTC_3484b/fast && /usr/bin/gmake -f CMakeFiles/cmTC_3484b.dir/build.make CMakeFiles/cmTC_3484b.dir/build gmake[1]: Entering directory '/var/tmp/portage/net-libs/google-cloud-cpp-0.10.0-r1/work/google-cloud-cpp-0.10.0_build/CMakeFiles/CMakeTmp' Building C object CMakeFiles/cmTC_3484b.dir/CheckFunctionExists.c.o /usr/lib/llvm/10/bin/x86_64-pc-linux-gnu-clang -DNDEBUG -O2 -pipe -march=native -frecord-gcc-switches -fno-diagnostics-color -DCHECK_FUNCTION_EXISTS=pthread_create -o CMakeFiles/cmTC_3484b.dir/CheckFunctionExists.c.o -c /usr/share/cmake/Modules/CheckFunctionExists.c Linking C executable cmTC_3484b /usr/bin/cmake -E cmake_link_script CMakeFiles/cmTC_3484b.dir/link.txt --verbose=1 /usr/lib/llvm/10/bin/x86_64-pc-linux-gnu-clang -O2 -pipe -march=native -frecord-gcc-switches -fno-diagnostics-color -DCHECK_FUNCTION_EXISTS=pthread_create -Wl,-O1 -Wl,--as-needed -Wl,--defsym=__gentoo_check_ldflags__=0 -fuse-ld=lld CMakeFiles/cmTC_3484b.dir/CheckFunctionExists.c.o -o cmTC_3484b -lpthreads ld.lld: error: unable to find library -lpthreads clang-10: error: linker command failed with exit code 1 (use -v to see invocation) gmake[1]: *** [CMakeFiles/cmTC_3484b.dir/build.make:106: cmTC_3484b] Error 1 gmake[1]: Leaving directory '/var/tmp/portage/net-libs/google-cloud-cpp-0.10.0-r1/work/google-cloud-cpp-0.10.0_build/CMakeFiles/CMakeTmp' gmake: *** [Makefile:140: cmTC_3484b/fast] Error 2 Determining if the RUSAGE_THREAD exist failed with the following output: Change Dir: /var/tmp/portage/net-libs/google-cloud-cpp-0.10.0-r1/work/google-cloud-cpp-0.10.0_build/CMakeFiles/CMakeTmp Run Build Command(s):/usr/bin/gmake cmTC_1e54e/fast && /usr/bin/gmake -f CMakeFiles/cmTC_1e54e.dir/build.make CMakeFiles/cmTC_1e54e.dir/build gmake[1]: Entering directory '/var/tmp/portage/net-libs/google-cloud-cpp-0.10.0-r1/work/google-cloud-cpp-0.10.0_build/CMakeFiles/CMakeTmp' Building C object CMakeFiles/cmTC_1e54e.dir/CheckSymbolExists.c.o /usr/lib/llvm/10/bin/x86_64-pc-linux-gnu-clang -DNDEBUG -O2 -pipe -march=native -frecord-gcc-switches -fno-diagnostics-color -o CMakeFiles/cmTC_1e54e.dir/CheckSymbolExists.c.o -c /var/tmp/portage/net-libs/google-cloud-cpp-0.10.0-r1/work/google-cloud-cpp-0.10.0_build/CMakeFiles/CMakeTmp/CheckSymbolExists.c /var/tmp/portage/net-libs/google-cloud-cpp-0.10.0-r1/work/google-cloud-cpp-0.10.0_build/CMakeFiles/CMakeTmp/CheckSymbolExists.c:8:19: error: use of undeclared identifier 'RUSAGE_THREAD' return ((int*)(&RUSAGE_THREAD))[argc]; ^ 1 error generated. gmake[1]: *** [CMakeFiles/cmTC_1e54e.dir/build.make:85: CMakeFiles/cmTC_1e54e.dir/CheckSymbolExists.c.o] Error 1 gmake[1]: Leaving directory '/var/tmp/portage/net-libs/google-cloud-cpp-0.10.0-r1/work/google-cloud-cpp-0.10.0_build/CMakeFiles/CMakeTmp' gmake: *** [Makefile:140: cmTC_1e54e/fast] Error 2 File /var/tmp/portage/net-libs/google-cloud-cpp-0.10.0-r1/work/google-cloud-cpp-0.10.0_build/CMakeFiles/CMakeTmp/CheckSymbolExists.c: /* */ #include int main(int argc, char** argv) { (void)argv; #ifndef RUSAGE_THREAD return ((int*)(&RUSAGE_THREAD))[argc]; #else (void)argc; return 0; #endif }