Performing C SOURCE FILE Test CMAKE_HAVE_LIBC_PTHREAD failed with the following output:
Change Dir: /home/naourr/work/instance-1/output-1/build/domoticz-2020.1/CMakeFiles/CMakeTmp

Run Build Command(s):/usr/bin/gmake cmTC_113bd/fast && gmake[1]: Entering directory '/home/naourr/work/instance-1/output-1/build/domoticz-2020.1/CMakeFiles/CMakeTmp'
/usr/bin/gmake  -f CMakeFiles/cmTC_113bd.dir/build.make CMakeFiles/cmTC_113bd.dir/build
gmake[2]: Entering directory '/home/naourr/work/instance-1/output-1/build/domoticz-2020.1/CMakeFiles/CMakeTmp'
Building C object CMakeFiles/cmTC_113bd.dir/src.c.o
/home/naourr/work/instance-1/output-1/host/bin/mips-linux-gnu-gcc --sysroot=/home/naourr/work/instance-1/output-1/host/mips64el-buildroot-linux-gnu/sysroot   -D_LARGEFILE_SOURCE -D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64 -O2 -DCMAKE_HAVE_LIBC_PTHREAD  -DNDEBUG   -o CMakeFiles/cmTC_113bd.dir/src.c.o   -c /home/naourr/work/instance-1/output-1/build/domoticz-2020.1/CMakeFiles/CMakeTmp/src.c
Linking C executable cmTC_113bd
/usr/bin/cmake -E cmake_link_script CMakeFiles/cmTC_113bd.dir/link.txt --verbose=1
/home/naourr/work/instance-1/output-1/host/bin/mips-linux-gnu-gcc --sysroot=/home/naourr/work/instance-1/output-1/host/mips64el-buildroot-linux-gnu/sysroot -D_LARGEFILE_SOURCE -D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64 -O2 -DCMAKE_HAVE_LIBC_PTHREAD  -DNDEBUG    CMakeFiles/cmTC_113bd.dir/src.c.o  -o cmTC_113bd 
CMakeFiles/cmTC_113bd.dir/src.c.o: In function `main':
src.c:(.text.startup+0x18): undefined reference to `pthread_create'
src.c:(.text.startup+0x28): undefined reference to `pthread_create'
src.c:(.text.startup+0x30): undefined reference to `pthread_detach'
src.c:(.text.startup+0x34): undefined reference to `pthread_detach'
src.c:(.text.startup+0x3c): undefined reference to `pthread_cancel'
src.c:(.text.startup+0x40): undefined reference to `pthread_cancel'
src.c:(.text.startup+0x4c): undefined reference to `pthread_join'
src.c:(.text.startup+0x50): undefined reference to `pthread_join'
src.c:(.text.startup+0x58): undefined reference to `pthread_atfork'
src.c:(.text.startup+0x64): undefined reference to `pthread_atfork'
collect2: error: ld returned 1 exit status
gmake[2]: *** [CMakeFiles/cmTC_113bd.dir/build.make:107: cmTC_113bd] Error 1
gmake[2]: Leaving directory '/home/naourr/work/instance-1/output-1/build/domoticz-2020.1/CMakeFiles/CMakeTmp'
gmake[1]: *** [Makefile:141: cmTC_113bd/fast] Error 2
gmake[1]: Leaving directory '/home/naourr/work/instance-1/output-1/build/domoticz-2020.1/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: /home/naourr/work/instance-1/output-1/build/domoticz-2020.1/CMakeFiles/CMakeTmp

Run Build Command(s):/usr/bin/gmake cmTC_1169c/fast && gmake[1]: Entering directory '/home/naourr/work/instance-1/output-1/build/domoticz-2020.1/CMakeFiles/CMakeTmp'
/usr/bin/gmake  -f CMakeFiles/cmTC_1169c.dir/build.make CMakeFiles/cmTC_1169c.dir/build
gmake[2]: Entering directory '/home/naourr/work/instance-1/output-1/build/domoticz-2020.1/CMakeFiles/CMakeTmp'
Building C object CMakeFiles/cmTC_1169c.dir/CheckFunctionExists.c.o
/home/naourr/work/instance-1/output-1/host/bin/mips-linux-gnu-gcc --sysroot=/home/naourr/work/instance-1/output-1/host/mips64el-buildroot-linux-gnu/sysroot   -D_LARGEFILE_SOURCE -D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64 -O2 -DCHECK_FUNCTION_EXISTS=pthread_create  -DNDEBUG   -o CMakeFiles/cmTC_1169c.dir/CheckFunctionExists.c.o   -c /usr/share/cmake/Modules/CheckFunctionExists.c
Linking C executable cmTC_1169c
/usr/bin/cmake -E cmake_link_script CMakeFiles/cmTC_1169c.dir/link.txt --verbose=1
/home/naourr/work/instance-1/output-1/host/bin/mips-linux-gnu-gcc --sysroot=/home/naourr/work/instance-1/output-1/host/mips64el-buildroot-linux-gnu/sysroot -D_LARGEFILE_SOURCE -D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64 -O2 -DCHECK_FUNCTION_EXISTS=pthread_create  -DNDEBUG    CMakeFiles/cmTC_1169c.dir/CheckFunctionExists.c.o  -o cmTC_1169c  -lpthreads 
/home/naourr/work/instance-1/output-1/host/opt/ext-toolchain/bin/../lib/gcc/mips-linux-gnu/5.3.0/../../../../mips-linux-gnu/bin/ld: cannot find -lpthreads
collect2: error: ld returned 1 exit status
gmake[2]: *** [CMakeFiles/cmTC_1169c.dir/build.make:107: cmTC_1169c] Error 1
gmake[2]: Leaving directory '/home/naourr/work/instance-1/output-1/build/domoticz-2020.1/CMakeFiles/CMakeTmp'
gmake[1]: *** [Makefile:141: cmTC_1169c/fast] Error 2
gmake[1]: Leaving directory '/home/naourr/work/instance-1/output-1/build/domoticz-2020.1/CMakeFiles/CMakeTmp'