diff --git a/Objects/unicodeobject.c b/Objects/unicodeobject.c
index 00bfff2..874e80e 100644
--- a/Objects/unicodeobject.c
+++ b/Objects/unicodeobject.c
@@ -13229,7 +13229,7 @@
     if (writer) {
         if (_PyUnicodeWriter_Prepare(writer, len, 127) == -1)
             return -1;
-        memcpy(writer->data + writer->pos * writer->kind,
+        memcpy((char*)writer->data + writer->pos * writer->kind,
                p,
                len);
         writer->pos += len;