Performing C++ SOURCE FILE Test CMAKE_HAVE_LIBC_PTHREAD failed with the following output:
Change Dir: /nvme/rc-buildroot-test/scripts/instance-0/output-1/build/host-libabseil-cpp-20200923.2/CMakeFiles/CMakeTmp

Run Build Command(s):/usr/bin/make cmTC_bbc1e/fast && make[1]: Entering directory '/nvme/rc-buildroot-test/scripts/instance-0/output-1/build/host-libabseil-cpp-20200923.2/CMakeFiles/CMakeTmp'
/usr/bin/make -f CMakeFiles/cmTC_bbc1e.dir/build.make CMakeFiles/cmTC_bbc1e.dir/build
make[2]: Entering directory '/nvme/rc-buildroot-test/scripts/instance-0/output-1/build/host-libabseil-cpp-20200923.2/CMakeFiles/CMakeTmp'
Building CXX object CMakeFiles/cmTC_bbc1e.dir/src.cxx.o
/usr/bin/g++    -O2 -I/nvme/rc-buildroot-test/scripts/instance-0/output-1/host/include -DCMAKE_HAVE_LIBC_PTHREAD   -o CMakeFiles/cmTC_bbc1e.dir/src.cxx.o -c /nvme/rc-buildroot-test/scripts/instance-0/output-1/build/host-libabseil-cpp-20200923.2/CMakeFiles/CMakeTmp/src.cxx
Linking CXX executable cmTC_bbc1e
/nvme/rc-buildroot-test/scripts/instance-0/output-1/host/bin/cmake -E cmake_link_script CMakeFiles/cmTC_bbc1e.dir/link.txt --verbose=1
/usr/bin/g++  -O2 -I/nvme/rc-buildroot-test/scripts/instance-0/output-1/host/include -DCMAKE_HAVE_LIBC_PTHREAD  -L/nvme/rc-buildroot-test/scripts/instance-0/output-1/host/lib -Wl,-rpath,/nvme/rc-buildroot-test/scripts/instance-0/output-1/host/lib  CMakeFiles/cmTC_bbc1e.dir/src.cxx.o  -o cmTC_bbc1e 
CMakeFiles/cmTC_bbc1e.dir/src.cxx.o: In function `main':
src.cxx:(.text.startup+0x21): undefined reference to `pthread_create'
src.cxx:(.text.startup+0x2a): undefined reference to `pthread_detach'
src.cxx:(.text.startup+0x35): undefined reference to `pthread_join'
src.cxx:(.text.startup+0x40): undefined reference to `pthread_atfork'
collect2: error: ld returned 1 exit status
CMakeFiles/cmTC_bbc1e.dir/build.make:86: recipe for target 'cmTC_bbc1e' failed
make[2]: *** [cmTC_bbc1e] Error 1
make[2]: Leaving directory '/nvme/rc-buildroot-test/scripts/instance-0/output-1/build/host-libabseil-cpp-20200923.2/CMakeFiles/CMakeTmp'
Makefile:121: recipe for target 'cmTC_bbc1e/fast' failed
make[1]: *** [cmTC_bbc1e/fast] Error 2
make[1]: Leaving directory '/nvme/rc-buildroot-test/scripts/instance-0/output-1/build/host-libabseil-cpp-20200923.2/CMakeFiles/CMakeTmp'


Source file was:
#include <pthread.h>

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: /nvme/rc-buildroot-test/scripts/instance-0/output-1/build/host-libabseil-cpp-20200923.2/CMakeFiles/CMakeTmp

Run Build Command(s):/usr/bin/make cmTC_7e0a6/fast && make[1]: Entering directory '/nvme/rc-buildroot-test/scripts/instance-0/output-1/build/host-libabseil-cpp-20200923.2/CMakeFiles/CMakeTmp'
/usr/bin/make -f CMakeFiles/cmTC_7e0a6.dir/build.make CMakeFiles/cmTC_7e0a6.dir/build
make[2]: Entering directory '/nvme/rc-buildroot-test/scripts/instance-0/output-1/build/host-libabseil-cpp-20200923.2/CMakeFiles/CMakeTmp'
Building CXX object CMakeFiles/cmTC_7e0a6.dir/CheckFunctionExists.cxx.o
/usr/bin/g++    -O2 -I/nvme/rc-buildroot-test/scripts/instance-0/output-1/host/include -DCHECK_FUNCTION_EXISTS=pthread_create   -o CMakeFiles/cmTC_7e0a6.dir/CheckFunctionExists.cxx.o -c /nvme/rc-buildroot-test/scripts/instance-0/output-1/build/host-libabseil-cpp-20200923.2/CMakeFiles/CheckLibraryExists/CheckFunctionExists.cxx
Linking CXX executable cmTC_7e0a6
/nvme/rc-buildroot-test/scripts/instance-0/output-1/host/bin/cmake -E cmake_link_script CMakeFiles/cmTC_7e0a6.dir/link.txt --verbose=1
/usr/bin/g++  -O2 -I/nvme/rc-buildroot-test/scripts/instance-0/output-1/host/include -DCHECK_FUNCTION_EXISTS=pthread_create  -L/nvme/rc-buildroot-test/scripts/instance-0/output-1/host/lib -Wl,-rpath,/nvme/rc-buildroot-test/scripts/instance-0/output-1/host/lib  CMakeFiles/cmTC_7e0a6.dir/CheckFunctionExists.cxx.o  -o cmTC_7e0a6 -lpthreads 
/usr/bin/ld: cannot find -lpthreads
collect2: error: ld returned 1 exit status
CMakeFiles/cmTC_7e0a6.dir/build.make:86: recipe for target 'cmTC_7e0a6' failed
make[2]: *** [cmTC_7e0a6] Error 1
make[2]: Leaving directory '/nvme/rc-buildroot-test/scripts/instance-0/output-1/build/host-libabseil-cpp-20200923.2/CMakeFiles/CMakeTmp'
Makefile:121: recipe for target 'cmTC_7e0a6/fast' failed
make[1]: *** [cmTC_7e0a6/fast] Error 2
make[1]: Leaving directory '/nvme/rc-buildroot-test/scripts/instance-0/output-1/build/host-libabseil-cpp-20200923.2/CMakeFiles/CMakeTmp'