check_c_source_compiles(
        "#include <vecintrin.h>
        int main(void) {
            unsigned long long a __attribute__((vector_size(16))) = { 0 };
            unsigned long long b __attribute__((vector_size(16))) = { 0 };
            unsigned char c __attribute__((vector_size(16))) = { 0 };
            c = vec_gfmsum_accum_128(a, b, c);
            return c[0];
        }"
        HAVE_VGFMA_INTRIN FAIL_REGEX "not supported")