diff --git a/libavformat/rpl.c b/libavformat/rpl.c
index e971d0588f..b30d769efb 100644
--- a/libavformat/rpl.c
+++ b/libavformat/rpl.c
@@ -102,7 +102,7 @@ static AVRational read_fps(const char* line, int* error)
         line++;
     for (; *line>='0' && *line<='9'; line++) {
         // Truncate any numerator too large to fit into an int64_t
-        if (num > (INT64_MAX - 9) / 10 || den > INT64_MAX / 10)
+        if (num > (INT64_MAX - 9) / 10ULL || den > INT64_MAX / 10ULL)
             break;
         num  = 10 * num + (*line - '0');
         den *= 10;