1 files changed, 3 insertions, 2 deletions

diff --git a/lobject.c b/lobject.c
index 68566a2b..57fc6a91 100644
--- a/lobject.c
+++ b/lobject.c
@@ -382,7 +382,7 @@ size_t luaO_str2num (const char *s, TValue *o) {
 }
 
 
-int luaO_utf8esc (char *buff, unsigned long x) {
+int luaO_utf8esc (char *buff, l_uint32 x) {
   int n = 1;  /* number of bytes put in buffer (backwards) */
   lua_assert(x <= 0x7FFFFFFFu);
   if (x < 0x80)  /* ascii? */
@@ -637,7 +637,8 @@ const char *luaO_pushvfstring (lua_State *L, const char *fmt, va_list argp) {
       }
       case 'U': {  /* an 'unsigned long' as a UTF-8 sequence */
         char bf[UTF8BUFFSZ];
-        int len = luaO_utf8esc(bf, va_arg(argp, unsigned long));
+        unsigned long arg = va_arg(argp, unsigned long);
+        int len = luaO_utf8esc(bf, cast(l_uint32, arg));
         addstr2buff(&buff, bf + UTF8BUFFSZ - len, cast_uint(len));
         break;
       }