Determining if the pthread_create exist failed with the following output: Change Dir: /home/naourr/work/instance-1/output/build/gnuradio-3.7.13.3/buildroot-build/CMakeFiles/CMakeTmp Run Build Command:"/usr/bin/gmake" "cmTC_e7efe/fast" gmake[1]: Entering directory '/home/naourr/work/instance-1/output/build/gnuradio-3.7.13.3/buildroot-build/CMakeFiles/CMakeTmp' /usr/bin/gmake -f CMakeFiles/cmTC_e7efe.dir/build.make CMakeFiles/cmTC_e7efe.dir/build gmake[2]: Entering directory '/home/naourr/work/instance-1/output/build/gnuradio-3.7.13.3/buildroot-build/CMakeFiles/CMakeTmp' Building C object CMakeFiles/cmTC_e7efe.dir/CheckSymbolExists.c.o /home/naourr/work/instance-1/output/host/bin/aarch64_be-linux-gnu-gcc --sysroot=/home/naourr/work/instance-1/output/host/aarch64_be-buildroot-linux-gnu/sysroot -D_LARGEFILE_SOURCE -D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64 -Os -std=gnu99 -fvisibility=hidden -Wsign-compare -Wall -Wno-uninitialized -DNDEBUG -o CMakeFiles/cmTC_e7efe.dir/CheckSymbolExists.c.o -c /home/naourr/work/instance-1/output/build/gnuradio-3.7.13.3/buildroot-build/CMakeFiles/CMakeTmp/CheckSymbolExists.c Linking C executable cmTC_e7efe /usr/bin/cmake -E cmake_link_script CMakeFiles/cmTC_e7efe.dir/link.txt --verbose=1 /home/naourr/work/instance-1/output/host/bin/aarch64_be-linux-gnu-gcc --sysroot=/home/naourr/work/instance-1/output/host/aarch64_be-buildroot-linux-gnu/sysroot -D_LARGEFILE_SOURCE -D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64 -Os -std=gnu99 -fvisibility=hidden -Wsign-compare -Wall -Wno-uninitialized -DNDEBUG -rdynamic CMakeFiles/cmTC_e7efe.dir/CheckSymbolExists.c.o -o cmTC_e7efe CMakeFiles/cmTC_e7efe.dir/CheckSymbolExists.c.o: In function `main': CheckSymbolExists.c:(.text.startup+0x0): undefined reference to `pthread_create' CheckSymbolExists.c:(.text.startup+0x4): undefined reference to `pthread_create' collect2: error: ld returned 1 exit status gmake[2]: *** [CMakeFiles/cmTC_e7efe.dir/build.make:87: cmTC_e7efe] Error 1 gmake[2]: Leaving directory '/home/naourr/work/instance-1/output/build/gnuradio-3.7.13.3/buildroot-build/CMakeFiles/CMakeTmp' gmake[1]: *** [Makefile:126: cmTC_e7efe/fast] Error 2 gmake[1]: Leaving directory '/home/naourr/work/instance-1/output/build/gnuradio-3.7.13.3/buildroot-build/CMakeFiles/CMakeTmp' File /home/naourr/work/instance-1/output/build/gnuradio-3.7.13.3/buildroot-build/CMakeFiles/CMakeTmp/CheckSymbolExists.c: /* */ #include 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: /home/naourr/work/instance-1/output/build/gnuradio-3.7.13.3/buildroot-build/CMakeFiles/CMakeTmp Run Build Command:"/usr/bin/gmake" "cmTC_0691d/fast" gmake[1]: Entering directory '/home/naourr/work/instance-1/output/build/gnuradio-3.7.13.3/buildroot-build/CMakeFiles/CMakeTmp' /usr/bin/gmake -f CMakeFiles/cmTC_0691d.dir/build.make CMakeFiles/cmTC_0691d.dir/build gmake[2]: Entering directory '/home/naourr/work/instance-1/output/build/gnuradio-3.7.13.3/buildroot-build/CMakeFiles/CMakeTmp' Building C object CMakeFiles/cmTC_0691d.dir/CheckFunctionExists.c.o /home/naourr/work/instance-1/output/host/bin/aarch64_be-linux-gnu-gcc --sysroot=/home/naourr/work/instance-1/output/host/aarch64_be-buildroot-linux-gnu/sysroot -D_LARGEFILE_SOURCE -D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64 -Os -std=gnu99 -fvisibility=hidden -Wsign-compare -Wall -Wno-uninitialized -DCHECK_FUNCTION_EXISTS=pthread_create -DNDEBUG -o CMakeFiles/cmTC_0691d.dir/CheckFunctionExists.c.o -c /usr/share/cmake/Modules/CheckFunctionExists.c Linking C executable cmTC_0691d /usr/bin/cmake -E cmake_link_script CMakeFiles/cmTC_0691d.dir/link.txt --verbose=1 /home/naourr/work/instance-1/output/host/bin/aarch64_be-linux-gnu-gcc --sysroot=/home/naourr/work/instance-1/output/host/aarch64_be-buildroot-linux-gnu/sysroot -D_LARGEFILE_SOURCE -D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64 -Os -std=gnu99 -fvisibility=hidden -Wsign-compare -Wall -Wno-uninitialized -DCHECK_FUNCTION_EXISTS=pthread_create -DNDEBUG -rdynamic CMakeFiles/cmTC_0691d.dir/CheckFunctionExists.c.o -o cmTC_0691d -lpthreads /home/naourr/work/instance-1/output/host/opt/ext-toolchain/bin/../lib/gcc/aarch64_be-linux-gnu/7.3.1/../../../../aarch64_be-linux-gnu/bin/ld: cannot find -lpthreads collect2: error: ld returned 1 exit status gmake[2]: *** [CMakeFiles/cmTC_0691d.dir/build.make:87: cmTC_0691d] Error 1 gmake[2]: Leaving directory '/home/naourr/work/instance-1/output/build/gnuradio-3.7.13.3/buildroot-build/CMakeFiles/CMakeTmp' gmake[1]: *** [Makefile:126: cmTC_0691d/fast] Error 2 gmake[1]: Leaving directory '/home/naourr/work/instance-1/output/build/gnuradio-3.7.13.3/buildroot-build/CMakeFiles/CMakeTmp'