Determining if the pthread_create exist failed with the following output:
Change Dir: /mnt/f/c++ projects/pistache-test/pistache/build/CMakeFiles/CMakeTmp

Run Build Command:"/usr/bin/make" "cmTC_28bff/fast"
/usr/bin/make -f CMakeFiles/cmTC_28bff.dir/build.make CMakeFiles/cmTC_28bff.dir/build
make[1]: Вход в каталог `/mnt/f/c++ projects/pistache-test/pistache/build/CMakeFiles/CMakeTmp'
Building C object CMakeFiles/cmTC_28bff.dir/CheckSymbolExists.c.o
/usr/bin/gcc-4.9     -o CMakeFiles/cmTC_28bff.dir/CheckSymbolExists.c.o   -c "/mnt/f/c++ projects/pistache-test/pistache/build/CMakeFiles/CMakeTmp/CheckSymbolExists.c"
Linking C executable cmTC_28bff
/usr/local/bin/cmake -E cmake_link_script CMakeFiles/cmTC_28bff.dir/link.txt --verbose=1
/usr/bin/gcc-4.9       CMakeFiles/cmTC_28bff.dir/CheckSymbolExists.c.o  -o cmTC_28bff -rdynamic 
CMakeFiles/cmTC_28bff.dir/CheckSymbolExists.c.o: In function `main':
CheckSymbolExists.c:(.text+0x16): undefined reference to `pthread_create'
collect2: error: ld returned 1 exit status
make[1]: *** [cmTC_28bff] Ошибка 1
make[1]: Выход из каталога `/mnt/f/c++ projects/pistache-test/pistache/build/CMakeFiles/CMakeTmp'
make: *** [cmTC_28bff/fast] Ошибка 2

File /mnt/f/c++ projects/pistache-test/pistache/build/CMakeFiles/CMakeTmp/CheckSymbolExists.c:
/* */
#include <pthread.h>

int main(int argc, char** argv)
{
  (void)argv;
#ifndef pthread_create
  return ((int*)(&pthread_create))[argc];
#else
  (void)argc;
  return 0;
#endif
}

Determining if the function pthread_create exists in the pthreads failed with the following output:
Change Dir: /mnt/f/c++ projects/pistache-test/pistache/build/CMakeFiles/CMakeTmp

Run Build Command:"/usr/bin/make" "cmTC_c8219/fast"
/usr/bin/make -f CMakeFiles/cmTC_c8219.dir/build.make CMakeFiles/cmTC_c8219.dir/build
make[1]: Вход в каталог `/mnt/f/c++ projects/pistache-test/pistache/build/CMakeFiles/CMakeTmp'
Building C object CMakeFiles/cmTC_c8219.dir/CheckFunctionExists.c.o
/usr/bin/gcc-4.9    -DCHECK_FUNCTION_EXISTS=pthread_create   -o CMakeFiles/cmTC_c8219.dir/CheckFunctionExists.c.o   -c /usr/local/share/cmake-3.6/Modules/CheckFunctionExists.c
Linking C executable cmTC_c8219
/usr/local/bin/cmake -E cmake_link_script CMakeFiles/cmTC_c8219.dir/link.txt --verbose=1
/usr/bin/gcc-4.9   -DCHECK_FUNCTION_EXISTS=pthread_create    CMakeFiles/cmTC_c8219.dir/CheckFunctionExists.c.o  -o cmTC_c8219 -rdynamic -lpthreads 
/usr/bin/ld: cannot find -lpthreads
collect2: error: ld returned 1 exit status
make[1]: *** [cmTC_c8219] Ошибка 1
make[1]: Выход из каталога `/mnt/f/c++ projects/pistache-test/pistache/build/CMakeFiles/CMakeTmp'
make: *** [cmTC_c8219/fast] Ошибка 2