diff --git a/runtime/internal/lib/hash/maphash/maphash.go b/runtime/internal/lib/hash/maphash/maphash.go
index a530004c..c590588a 100644
--- a/runtime/internal/lib/hash/maphash/maphash.go
+++ b/runtime/internal/lib/hash/maphash/maphash.go
@@ -23,3 +23,7 @@ func runtime_rand() uint64
 
 //go:linkname runtime_memhash github.com/goplus/llgo/runtime/internal/runtime.memhash
 func runtime_memhash(p unsafe.Pointer, seed, s uintptr) uintptr
+
+func randUint64() uint64 {
+	return runtime_rand()
+}