These functions may be available as inlines or as libgcc functions. In the former case, a __GCC_HAVE_SYNC_COMPARE_AND_SWAP_n macro is defined. But we still want to use these functions in the latter case, when we don't have our own implementation.
These functions may be available as inlines or as libgcc functions. In the former case, a __GCC_HAVE_SYNC_COMPARE_AND_SWAP_n macro is defined. But we still want to use these functions in the latter case, when we don't have our own implementation.