+# for gcc and old Clang compiles we need -latomic for 128-bit atomic ops
+atomic_check_code = '''
+int main(void)
+{
+ __int128 a = 0;
+ __int128 b;
+
+ b = __atomic_load_n(&a, __ATOMIC_RELAXED);
+ __atomic_store(&b, &a, __ATOMIC_RELAXED);
+ __atomic_store_n(&b, a, __ATOMIC_RELAXED);
+ return 0;
+}
+'''
+if not cc.links(atomic_check_code)
+ libatomic_dep = cc.find_library('atomic', required: false)
+ if not libatomic_dep.found()
+ build = false
+ reason = 'missing dependency, "libatomic"'
+ subdir_done()
+ endif