Determining if the pthread_create exist failed with the following output: Change Dir: /accts/mlweber1/instance-1/output/build/gnuradio-3.7.13.3/buildroot-build/CMakeFiles/CMakeTmp Run Build Command:"/usr/bin/make" "cmTC_41a48/fast" make[1]: Entering directory `/accts/mlweber1/instance-1/output/build/gnuradio-3.7.13.3/buildroot-build/CMakeFiles/CMakeTmp' /usr/bin/make -f CMakeFiles/cmTC_41a48.dir/build.make CMakeFiles/cmTC_41a48.dir/build make[2]: Entering directory `/accts/mlweber1/instance-1/output/build/gnuradio-3.7.13.3/buildroot-build/CMakeFiles/CMakeTmp' Building C object CMakeFiles/cmTC_41a48.dir/CheckSymbolExists.c.o /accts/mlweber1/instance-1/output/host/bin/arm-none-linux-gnueabi-gcc --sysroot=/accts/mlweber1/instance-1/output/host/arm-buildroot-linux-gnueabi/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_41a48.dir/CheckSymbolExists.c.o -c /accts/mlweber1/instance-1/output/build/gnuradio-3.7.13.3/buildroot-build/CMakeFiles/CMakeTmp/CheckSymbolExists.c Linking C executable cmTC_41a48 /accts/mlweber1/instance-1/output/host/bin/cmake -E cmake_link_script CMakeFiles/cmTC_41a48.dir/link.txt --verbose=1 /accts/mlweber1/instance-1/output/host/bin/arm-none-linux-gnueabi-gcc --sysroot=/accts/mlweber1/instance-1/output/host/arm-buildroot-linux-gnueabi/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_41a48.dir/CheckSymbolExists.c.o -o cmTC_41a48 CMakeFiles/cmTC_41a48.dir/CheckSymbolExists.c.o: In function `main': CheckSymbolExists.c:(.text.startup+0xc): undefined reference to `pthread_create' collect2: error: ld returned 1 exit status make[2]: *** [cmTC_41a48] Error 1 make[2]: Leaving directory `/accts/mlweber1/instance-1/output/build/gnuradio-3.7.13.3/buildroot-build/CMakeFiles/CMakeTmp' make[1]: *** [cmTC_41a48/fast] Error 2 make[1]: Leaving directory `/accts/mlweber1/instance-1/output/build/gnuradio-3.7.13.3/buildroot-build/CMakeFiles/CMakeTmp' File /accts/mlweber1/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: /accts/mlweber1/instance-1/output/build/gnuradio-3.7.13.3/buildroot-build/CMakeFiles/CMakeTmp Run Build Command:"/usr/bin/make" "cmTC_5c363/fast" make[1]: Entering directory `/accts/mlweber1/instance-1/output/build/gnuradio-3.7.13.3/buildroot-build/CMakeFiles/CMakeTmp' /usr/bin/make -f CMakeFiles/cmTC_5c363.dir/build.make CMakeFiles/cmTC_5c363.dir/build make[2]: Entering directory `/accts/mlweber1/instance-1/output/build/gnuradio-3.7.13.3/buildroot-build/CMakeFiles/CMakeTmp' Building C object CMakeFiles/cmTC_5c363.dir/CheckFunctionExists.c.o /accts/mlweber1/instance-1/output/host/bin/arm-none-linux-gnueabi-gcc --sysroot=/accts/mlweber1/instance-1/output/host/arm-buildroot-linux-gnueabi/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_5c363.dir/CheckFunctionExists.c.o -c /accts/mlweber1/instance-1/output/host/share/cmake-3.8/Modules/CheckFunctionExists.c Linking C executable cmTC_5c363 /accts/mlweber1/instance-1/output/host/bin/cmake -E cmake_link_script CMakeFiles/cmTC_5c363.dir/link.txt --verbose=1 /accts/mlweber1/instance-1/output/host/bin/arm-none-linux-gnueabi-gcc --sysroot=/accts/mlweber1/instance-1/output/host/arm-buildroot-linux-gnueabi/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_5c363.dir/CheckFunctionExists.c.o -o cmTC_5c363 -lpthreads /accts/mlweber1/instance-1/output/host/opt/ext-toolchain/bin/../lib/gcc/arm-none-linux-gnueabi/4.8.3/../../../../arm-none-linux-gnueabi/bin/ld: cannot find -lpthreads collect2: error: ld returned 1 exit status make[2]: *** [cmTC_5c363] Error 1 make[2]: Leaving directory `/accts/mlweber1/instance-1/output/build/gnuradio-3.7.13.3/buildroot-build/CMakeFiles/CMakeTmp' make[1]: *** [cmTC_5c363/fast] Error 2 make[1]: Leaving directory `/accts/mlweber1/instance-1/output/build/gnuradio-3.7.13.3/buildroot-build/CMakeFiles/CMakeTmp'