Performing C++ SOURCE FILE Test CMAKE_HAVE_LIBC_PTHREAD failed with the following output: Change Dir: /home/buildroot/autobuild/instance-1/output-1/build/libabseil-cpp-20200225/CMakeFiles/CMakeTmp Run Build Command(s):/usr/bin/make cmTC_fb30f/fast && make[1]: Entering directory '/home/buildroot/autobuild/instance-1/output-1/build/libabseil-cpp-20200225/CMakeFiles/CMakeTmp' /usr/bin/make -f CMakeFiles/cmTC_fb30f.dir/build.make CMakeFiles/cmTC_fb30f.dir/build make[2]: Entering directory '/home/buildroot/autobuild/instance-1/output-1/build/libabseil-cpp-20200225/CMakeFiles/CMakeTmp' Building CXX object CMakeFiles/cmTC_fb30f.dir/src.cxx.o /home/buildroot/autobuild/instance-1/output-1/host/bin/arc-buildroot-linux-gnu-g++ --sysroot=/home/buildroot/autobuild/instance-1/output-1/host/arc-buildroot-linux-gnu/sysroot -D_LARGEFILE_SOURCE -D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64 -Os -DCMAKE_HAVE_LIBC_PTHREAD -DNDEBUG -o CMakeFiles/cmTC_fb30f.dir/src.cxx.o -c /home/buildroot/autobuild/instance-1/output-1/build/libabseil-cpp-20200225/CMakeFiles/CMakeTmp/src.cxx Linking CXX executable cmTC_fb30f /home/buildroot/autobuild/instance-1/output-1/host/bin/cmake -E cmake_link_script CMakeFiles/cmTC_fb30f.dir/link.txt --verbose=1 /home/buildroot/autobuild/instance-1/output-1/host/bin/arc-buildroot-linux-gnu-g++ --sysroot=/home/buildroot/autobuild/instance-1/output-1/host/arc-buildroot-linux-gnu/sysroot -D_LARGEFILE_SOURCE -D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64 -Os -DCMAKE_HAVE_LIBC_PTHREAD -DNDEBUG CMakeFiles/cmTC_fb30f.dir/src.cxx.o -o cmTC_fb30f /home/buildroot/autobuild/instance-1/output-1/host/lib/gcc/arc-buildroot-linux-gnu/9.3.1/../../../../arc-buildroot-linux-gnu/bin/ld: CMakeFiles/cmTC_fb30f.dir/src.cxx.o: in function `main': src.cxx:(.text.startup+0x10): undefined reference to `pthread_create' /home/buildroot/autobuild/instance-1/output-1/host/lib/gcc/arc-buildroot-linux-gnu/9.3.1/../../../../arc-buildroot-linux-gnu/bin/ld: src.cxx:(.text.startup+0x10): undefined reference to `pthread_create' /home/buildroot/autobuild/instance-1/output-1/host/lib/gcc/arc-buildroot-linux-gnu/9.3.1/../../../../arc-buildroot-linux-gnu/bin/ld: src.cxx:(.text.startup+0x16): undefined reference to `pthread_detach' /home/buildroot/autobuild/instance-1/output-1/host/lib/gcc/arc-buildroot-linux-gnu/9.3.1/../../../../arc-buildroot-linux-gnu/bin/ld: src.cxx:(.text.startup+0x16): undefined reference to `pthread_detach' /home/buildroot/autobuild/instance-1/output-1/host/lib/gcc/arc-buildroot-linux-gnu/9.3.1/../../../../arc-buildroot-linux-gnu/bin/ld: src.cxx:(.text.startup+0x1e): undefined reference to `pthread_join' /home/buildroot/autobuild/instance-1/output-1/host/lib/gcc/arc-buildroot-linux-gnu/9.3.1/../../../../arc-buildroot-linux-gnu/bin/ld: src.cxx:(.text.startup+0x1e): undefined reference to `pthread_join' collect2: error: ld returned 1 exit status CMakeFiles/cmTC_fb30f.dir/build.make:86: recipe for target 'cmTC_fb30f' failed make[2]: *** [cmTC_fb30f] Error 1 make[2]: Leaving directory '/home/buildroot/autobuild/instance-1/output-1/build/libabseil-cpp-20200225/CMakeFiles/CMakeTmp' Makefile:121: recipe for target 'cmTC_fb30f/fast' failed make[1]: *** [cmTC_fb30f/fast] Error 2 make[1]: Leaving directory '/home/buildroot/autobuild/instance-1/output-1/build/libabseil-cpp-20200225/CMakeFiles/CMakeTmp' 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_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: /home/buildroot/autobuild/instance-1/output-1/build/libabseil-cpp-20200225/CMakeFiles/CMakeTmp Run Build Command(s):/usr/bin/make cmTC_c17ea/fast && make[1]: Entering directory '/home/buildroot/autobuild/instance-1/output-1/build/libabseil-cpp-20200225/CMakeFiles/CMakeTmp' /usr/bin/make -f CMakeFiles/cmTC_c17ea.dir/build.make CMakeFiles/cmTC_c17ea.dir/build make[2]: Entering directory '/home/buildroot/autobuild/instance-1/output-1/build/libabseil-cpp-20200225/CMakeFiles/CMakeTmp' Building CXX object CMakeFiles/cmTC_c17ea.dir/CheckFunctionExists.cxx.o /home/buildroot/autobuild/instance-1/output-1/host/bin/arc-buildroot-linux-gnu-g++ --sysroot=/home/buildroot/autobuild/instance-1/output-1/host/arc-buildroot-linux-gnu/sysroot -D_LARGEFILE_SOURCE -D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64 -Os -DCHECK_FUNCTION_EXISTS=pthread_create -DNDEBUG -o CMakeFiles/cmTC_c17ea.dir/CheckFunctionExists.cxx.o -c /home/buildroot/autobuild/instance-1/output-1/build/libabseil-cpp-20200225/CMakeFiles/CheckLibraryExists/CheckFunctionExists.cxx Linking CXX executable cmTC_c17ea /home/buildroot/autobuild/instance-1/output-1/host/bin/cmake -E cmake_link_script CMakeFiles/cmTC_c17ea.dir/link.txt --verbose=1 /home/buildroot/autobuild/instance-1/output-1/host/bin/arc-buildroot-linux-gnu-g++ --sysroot=/home/buildroot/autobuild/instance-1/output-1/host/arc-buildroot-linux-gnu/sysroot -D_LARGEFILE_SOURCE -D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64 -Os -DCHECK_FUNCTION_EXISTS=pthread_create -DNDEBUG CMakeFiles/cmTC_c17ea.dir/CheckFunctionExists.cxx.o -o cmTC_c17ea -lpthreads /home/buildroot/autobuild/instance-1/output-1/host/lib/gcc/arc-buildroot-linux-gnu/9.3.1/../../../../arc-buildroot-linux-gnu/bin/ld: cannot find -lpthreads collect2: error: ld returned 1 exit status CMakeFiles/cmTC_c17ea.dir/build.make:86: recipe for target 'cmTC_c17ea' failed make[2]: *** [cmTC_c17ea] Error 1 make[2]: Leaving directory '/home/buildroot/autobuild/instance-1/output-1/build/libabseil-cpp-20200225/CMakeFiles/CMakeTmp' Makefile:121: recipe for target 'cmTC_c17ea/fast' failed make[1]: *** [cmTC_c17ea/fast] Error 2 make[1]: Leaving directory '/home/buildroot/autobuild/instance-1/output-1/build/libabseil-cpp-20200225/CMakeFiles/CMakeTmp'