diff --git a/tools/checkwps/checkwps.c b/tools/checkwps/checkwps.c
index 6c4e404800..8549c9c0a0 100644
--- a/tools/checkwps/checkwps.c
+++ b/tools/checkwps/checkwps.c
@@ -326,7 +326,7 @@ int main(int argc, char **argv)
      * flawed wps */
     while (argv[filearg]) {
         const char* name = argv[filearg++];
-        char *ext = strrchr(name, '.');
+        const char *ext = strrchr(name, '.');
         struct skin_stats stats;
         printf("Checking %s...\n", name);
         if (!ext)