diff --git a/unit_test.c b/unit_test.c
index 077aeb3..ed5ca2f 100644
--- a/unit_test.c
+++ b/unit_test.c
@@ -255,12 +255,12 @@ int main(void) {
       "<img src=\"HTTPS://FOO.COM/x?b#c=tab1\"/> "
       "  <a href=\"http://cesanta.com\">some link</a>";
 
-    static const char *regex = "(?i)((https?://)[^\\s/'\"<>]+/?[^\\s'\"<>]*)";
+    static const char *regex = "((https?://)[^\\s/'\"<>]+/?[^\\s'\"<>]*)";
     struct slre_cap caps[2];
     int i, j = 0, str_len = (int) strlen(str);
 
     while (j < str_len &&
-           (i = slre_match(regex, str + j, str_len - j, caps, 2, 0)) > 0) {
+           (i = slre_match(regex, str + j, str_len - j, caps, 2, SLRE_IGNORE_CASE)) > 0) {
       printf("Found URL: [%.*s]\n", caps[0].len, caps[0].ptr);
       j += i;
     }