Performing C++ SOURCE FILE Test CC_HAS_STACK_REALIGN failed with the following output:
Change Dir: /home/buildroot/build/instance-0/output/build/x265-2.8/source/CMakeFiles/CMakeTmp

Run Build Command:"/usr/bin/make" "cmTC_380d7/fast"
make[1]: Entering directory '/home/buildroot/build/instance-0/output/build/x265-2.8/source/CMakeFiles/CMakeTmp'
/usr/bin/make -f CMakeFiles/cmTC_380d7.dir/build.make CMakeFiles/cmTC_380d7.dir/build
make[2]: Entering directory '/home/buildroot/build/instance-0/output/build/x265-2.8/source/CMakeFiles/CMakeTmp'
Building CXX object CMakeFiles/cmTC_380d7.dir/src.cxx.o
/home/buildroot/build/instance-0/output/host/bin/arm-linux-g++ --sysroot=/home/buildroot/build/instance-0/output/host/arm-buildroot-linux-musleabihf/sysroot    -D_LARGEFILE_SOURCE -D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64 -Os -DCC_HAS_STACK_REALIGN  -DNDEBUG   -mstackrealign -o CMakeFiles/cmTC_380d7.dir/src.cxx.o -c /home/buildroot/build/instance-0/output/build/x265-2.8/source/CMakeFiles/CMakeTmp/src.cxx
arm-linux-g++.br_real: error: unrecognized command line option '-mstackrealign'
CMakeFiles/cmTC_380d7.dir/build.make:65: recipe for target 'CMakeFiles/cmTC_380d7.dir/src.cxx.o' failed
make[2]: *** [CMakeFiles/cmTC_380d7.dir/src.cxx.o] Error 1
make[2]: Leaving directory '/home/buildroot/build/instance-0/output/build/x265-2.8/source/CMakeFiles/CMakeTmp'
Makefile:126: recipe for target 'cmTC_380d7/fast' failed
make[1]: *** [cmTC_380d7/fast] Error 2
make[1]: Leaving directory '/home/buildroot/build/instance-0/output/build/x265-2.8/source/CMakeFiles/CMakeTmp'

Source file was:
int main() { return 0; }