cmake HAVE_DECL___BUILTIN_CLZLL examples

HDFGroup/hdf5 config/cmake/LIBAEC/CMakeLists.txt :31 

check_c_source_compiles(
  "int main(void)\n{return __builtin_clzll(1LL);}"
  HAVE_DECL___BUILTIN_CLZLL)

InsightSoftwareConsortium/ITK Modules/ThirdParty/HDF5/src/itkhdf5/config/cmake/LIBAEC/CMakeLists.txt :31 

check_c_source_compiles(
  "int main(void)\n{return __builtin_clzll(1LL);}"
  HAVE_DECL___BUILTIN_CLZLL)