Performing C SOURCE FILE Test CMAKE_HAVE_LIBC_PTHREAD failed with the following output: Change Dir: /home/buildroot/autobuild/run/instance-2/output-1/build/kf5-kcoreaddons-5.47.0/CMakeFiles/CMakeTmp Run Build Command(s):/usr/bin/make cmTC_73932/fast && make[1]: Entering directory `/home/buildroot/autobuild/run/instance-2/output-1/build/kf5-kcoreaddons-5.47.0/CMakeFiles/CMakeTmp' /usr/bin/make -f CMakeFiles/cmTC_73932.dir/build.make CMakeFiles/cmTC_73932.dir/build make[2]: Entering directory `/home/buildroot/autobuild/run/instance-2/output-1/build/kf5-kcoreaddons-5.47.0/CMakeFiles/CMakeTmp' Building C object CMakeFiles/cmTC_73932.dir/src.c.o /home/buildroot/autobuild/run/instance-2/output-1/host/bin/nios2-linux-gcc --sysroot=/home/buildroot/autobuild/run/instance-2/output-1/host/nios2-buildroot-linux-gnu/sysroot -D_GNU_SOURCE -D_LARGEFILE64_SOURCE -D_LARGEFILE_SOURCE -D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64 -Os -D_FORTIFY_SOURCE=2 -std=iso9899:1990 -fno-common -Wall -Wextra -Wcast-align -Wchar-subscripts -Wformat-security -Wno-long-long -Wpointer-arith -Wundef -Wmissing-format-attribute -Wwrite-strings -Werror=implicit-function-declaration -DCMAKE_HAVE_LIBC_PTHREAD -DNDEBUG -o CMakeFiles/cmTC_73932.dir/src.c.o -c /home/buildroot/autobuild/run/instance-2/output-1/build/kf5-kcoreaddons-5.47.0/CMakeFiles/CMakeTmp/src.c Linking C executable cmTC_73932 /home/buildroot/autobuild/run/instance-2/output-1/host/bin/cmake -E cmake_link_script CMakeFiles/cmTC_73932.dir/link.txt --verbose=1 /home/buildroot/autobuild/run/instance-2/output-1/host/bin/nios2-linux-gcc --sysroot=/home/buildroot/autobuild/run/instance-2/output-1/host/nios2-buildroot-linux-gnu/sysroot -D_LARGEFILE_SOURCE -D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64 -Os -D_FORTIFY_SOURCE=2 -std=iso9899:1990 -fno-common -Wall -Wextra -Wcast-align -Wchar-subscripts -Wformat-security -Wno-long-long -Wpointer-arith -Wundef -Wmissing-format-attribute -Wwrite-strings -Werror=implicit-function-declaration -DCMAKE_HAVE_LIBC_PTHREAD -DNDEBUG CMakeFiles/cmTC_73932.dir/src.c.o -o cmTC_73932 /home/buildroot/autobuild/run/instance-2/output-1/host/opt/ext-toolchain/bin/../lib/gcc/nios2-buildroot-linux-gnu/8.3.0/../../../../nios2-buildroot-linux-gnu/bin/ld: CMakeFiles/cmTC_73932.dir/src.c.o: in function `main': src.c:(.text.startup+0x28): undefined reference to `pthread_create' /home/buildroot/autobuild/run/instance-2/output-1/host/opt/ext-toolchain/bin/../lib/gcc/nios2-buildroot-linux-gnu/8.3.0/../../../../nios2-buildroot-linux-gnu/bin/ld: src.c:(.text.startup+0x30): undefined reference to `pthread_detach' /home/buildroot/autobuild/run/instance-2/output-1/host/opt/ext-toolchain/bin/../lib/gcc/nios2-buildroot-linux-gnu/8.3.0/../../../../nios2-buildroot-linux-gnu/bin/ld: src.c:(.text.startup+0x3c): undefined reference to `pthread_join' collect2: error: ld returned 1 exit status make[2]: *** [cmTC_73932] Error 1 make[2]: Leaving directory `/home/buildroot/autobuild/run/instance-2/output-1/build/kf5-kcoreaddons-5.47.0/CMakeFiles/CMakeTmp' make[1]: *** [cmTC_73932/fast] Error 2 make[1]: Leaving directory `/home/buildroot/autobuild/run/instance-2/output-1/build/kf5-kcoreaddons-5.47.0/CMakeFiles/CMakeTmp' Source file was: #include void* test_func(void* data) { return data; } int main(void) { pthread_t thread; pthread_create(&thread, NULL, test_func, NULL); pthread_detach(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/buildroot/autobuild/run/instance-2/output-1/build/kf5-kcoreaddons-5.47.0/CMakeFiles/CMakeTmp Run Build Command(s):/usr/bin/make cmTC_a82f5/fast && make[1]: Entering directory `/home/buildroot/autobuild/run/instance-2/output-1/build/kf5-kcoreaddons-5.47.0/CMakeFiles/CMakeTmp' /usr/bin/make -f CMakeFiles/cmTC_a82f5.dir/build.make CMakeFiles/cmTC_a82f5.dir/build make[2]: Entering directory `/home/buildroot/autobuild/run/instance-2/output-1/build/kf5-kcoreaddons-5.47.0/CMakeFiles/CMakeTmp' Building C object CMakeFiles/cmTC_a82f5.dir/CheckFunctionExists.c.o /home/buildroot/autobuild/run/instance-2/output-1/host/bin/nios2-linux-gcc --sysroot=/home/buildroot/autobuild/run/instance-2/output-1/host/nios2-buildroot-linux-gnu/sysroot -D_GNU_SOURCE -D_LARGEFILE64_SOURCE -D_LARGEFILE_SOURCE -D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64 -Os -D_FORTIFY_SOURCE=2 -std=iso9899:1990 -fno-common -Wall -Wextra -Wcast-align -Wchar-subscripts -Wformat-security -Wno-long-long -Wpointer-arith -Wundef -Wmissing-format-attribute -Wwrite-strings -Werror=implicit-function-declaration -DCHECK_FUNCTION_EXISTS=pthread_create -DNDEBUG -o CMakeFiles/cmTC_a82f5.dir/CheckFunctionExists.c.o -c /home/buildroot/autobuild/run/instance-2/output-1/host/share/cmake-3.15/Modules/CheckFunctionExists.c Linking C executable cmTC_a82f5 /home/buildroot/autobuild/run/instance-2/output-1/host/bin/cmake -E cmake_link_script CMakeFiles/cmTC_a82f5.dir/link.txt --verbose=1 /home/buildroot/autobuild/run/instance-2/output-1/host/bin/nios2-linux-gcc --sysroot=/home/buildroot/autobuild/run/instance-2/output-1/host/nios2-buildroot-linux-gnu/sysroot -D_LARGEFILE_SOURCE -D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64 -Os -D_FORTIFY_SOURCE=2 -std=iso9899:1990 -fno-common -Wall -Wextra -Wcast-align -Wchar-subscripts -Wformat-security -Wno-long-long -Wpointer-arith -Wundef -Wmissing-format-attribute -Wwrite-strings -Werror=implicit-function-declaration -DCHECK_FUNCTION_EXISTS=pthread_create -DNDEBUG CMakeFiles/cmTC_a82f5.dir/CheckFunctionExists.c.o -o cmTC_a82f5 -lpthreads /home/buildroot/autobuild/run/instance-2/output-1/host/opt/ext-toolchain/bin/../lib/gcc/nios2-buildroot-linux-gnu/8.3.0/../../../../nios2-buildroot-linux-gnu/bin/ld: cannot find -lpthreads collect2: error: ld returned 1 exit status make[2]: *** [cmTC_a82f5] Error 1 make[2]: Leaving directory `/home/buildroot/autobuild/run/instance-2/output-1/build/kf5-kcoreaddons-5.47.0/CMakeFiles/CMakeTmp' make[1]: *** [cmTC_a82f5/fast] Error 2 make[1]: Leaving directory `/home/buildroot/autobuild/run/instance-2/output-1/build/kf5-kcoreaddons-5.47.0/CMakeFiles/CMakeTmp'