diff --git a/src/tool_urlglob.c b/src/tool_urlglob.c
index ac13d683d7d1bf98a9a9941063a50ddf6b6ae308..1644077f2876ea22fc5497f25ec63d6d433f2d77 100644
--- a/src/tool_urlglob.c
+++ b/src/tool_urlglob.c
@@ -249,8 +249,8 @@ static GlobCode glob_range(URLGlob *glob, char **patternp,
   else if(ISDIGIT(*pattern)) {
     /* numeric range detected */
     unsigned long min_n;
-    unsigned long max_n;
-    unsigned long step_n;
+    unsigned long max_n = 0;
+    unsigned long step_n = 0;
     char *endp;
 
     pat->type = UPTNumRange;