Performing C SOURCE FILE Test CMAKE_HAVE_LIBC_PTHREAD failed with the following output:
Change Dir: /nvmedata/autobuild/instance-29/output-1/build/libcodec2-1.0.1/buildroot-build/src/codec2_native/CMakeFiles/CMakeTmp

Run Build Command(s):/usr/bin/make cmTC_be14e/fast && make[4]: Entering directory '/nvmedata/autobuild/instance-29/output-1/build/libcodec2-1.0.1/buildroot-build/src/codec2_native/CMakeFiles/CMakeTmp'
/usr/bin/make  -f CMakeFiles/cmTC_be14e.dir/build.make CMakeFiles/cmTC_be14e.dir/build
make[5]: Entering directory '/nvmedata/autobuild/instance-29/output-1/build/libcodec2-1.0.1/buildroot-build/src/codec2_native/CMakeFiles/CMakeTmp'
Building C object CMakeFiles/cmTC_be14e.dir/src.c.o
/usr/bin/cc   -Wall -Wno-strict-overflow -std=gnu11 -fPIC -DCMAKE_HAVE_LIBC_PTHREAD -o CMakeFiles/cmTC_be14e.dir/src.c.o -c /nvmedata/autobuild/instance-29/output-1/build/libcodec2-1.0.1/buildroot-build/src/codec2_native/CMakeFiles/CMakeTmp/src.c
Linking C executable cmTC_be14e
/nvmedata/autobuild/instance-29/output-1/host/bin/cmake -E cmake_link_script CMakeFiles/cmTC_be14e.dir/link.txt --verbose=1
/usr/bin/cc  -Wall -Wno-strict-overflow -std=gnu11 -fPIC -DCMAKE_HAVE_LIBC_PTHREAD -rdynamic CMakeFiles/cmTC_be14e.dir/src.c.o -o cmTC_be14e  -lm 
/usr/bin/ld: CMakeFiles/cmTC_be14e.dir/src.c.o: in function `main':
src.c:(.text+0x46): undefined reference to `pthread_create'
/usr/bin/ld: src.c:(.text+0x52): undefined reference to `pthread_detach'
/usr/bin/ld: src.c:(.text+0x5e): undefined reference to `pthread_cancel'
/usr/bin/ld: src.c:(.text+0x6f): undefined reference to `pthread_join'
collect2: error: ld returned 1 exit status
make[5]: *** [CMakeFiles/cmTC_be14e.dir/build.make:106: cmTC_be14e] Error 1
make[5]: Leaving directory '/nvmedata/autobuild/instance-29/output-1/build/libcodec2-1.0.1/buildroot-build/src/codec2_native/CMakeFiles/CMakeTmp'
make[4]: *** [Makefile:140: cmTC_be14e/fast] Error 2
make[4]: Leaving directory '/nvmedata/autobuild/instance-29/output-1/build/libcodec2-1.0.1/buildroot-build/src/codec2_native/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_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: /nvmedata/autobuild/instance-29/output-1/build/libcodec2-1.0.1/buildroot-build/src/codec2_native/CMakeFiles/CMakeTmp

Run Build Command(s):/usr/bin/make cmTC_c3f9b/fast && make[4]: Entering directory '/nvmedata/autobuild/instance-29/output-1/build/libcodec2-1.0.1/buildroot-build/src/codec2_native/CMakeFiles/CMakeTmp'
/usr/bin/make  -f CMakeFiles/cmTC_c3f9b.dir/build.make CMakeFiles/cmTC_c3f9b.dir/build
make[5]: Entering directory '/nvmedata/autobuild/instance-29/output-1/build/libcodec2-1.0.1/buildroot-build/src/codec2_native/CMakeFiles/CMakeTmp'
Building C object CMakeFiles/cmTC_c3f9b.dir/CheckFunctionExists.c.o
/usr/bin/cc   -Wall -Wno-strict-overflow -std=gnu11 -fPIC -DCHECK_FUNCTION_EXISTS=pthread_create -o CMakeFiles/cmTC_c3f9b.dir/CheckFunctionExists.c.o -c /nvmedata/autobuild/instance-29/output-1/host/share/cmake-3.18/Modules/CheckFunctionExists.c
Linking C executable cmTC_c3f9b
/nvmedata/autobuild/instance-29/output-1/host/bin/cmake -E cmake_link_script CMakeFiles/cmTC_c3f9b.dir/link.txt --verbose=1
/usr/bin/cc  -Wall -Wno-strict-overflow -std=gnu11 -fPIC -DCHECK_FUNCTION_EXISTS=pthread_create -rdynamic CMakeFiles/cmTC_c3f9b.dir/CheckFunctionExists.c.o -o cmTC_c3f9b  -lpthreads -lm 
/usr/bin/ld: cannot find -lpthreads
collect2: error: ld returned 1 exit status
make[5]: *** [CMakeFiles/cmTC_c3f9b.dir/build.make:106: cmTC_c3f9b] Error 1
make[5]: Leaving directory '/nvmedata/autobuild/instance-29/output-1/build/libcodec2-1.0.1/buildroot-build/src/codec2_native/CMakeFiles/CMakeTmp'
make[4]: *** [Makefile:140: cmTC_c3f9b/fast] Error 2
make[4]: Leaving directory '/nvmedata/autobuild/instance-29/output-1/build/libcodec2-1.0.1/buildroot-build/src/codec2_native/CMakeFiles/CMakeTmp'