test-tool regex: call regfree(), fix memory leaks

Fix memory leaks in "test-tool regex" which have been there since
c91841594c (test-regex: Add a test to check for a bug in the regex
routines, 2012-09-01), as a result we can mark a test as passing with
SANITIZE=leak using "TEST_PASSES_SANITIZE_LEAK=true".

We could regfree() on the die() paths here, which would make some
invocations of valgrind(1) happy, but let's just target SANITIZE=leak
for now. Variables that are still reachable when we die() are not
reported as leaks.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

t/helper/test-regex.c

@@ -34,6 +34,7 @@ static int test_regex_bug(void)
 	if (m[0].rm_so == 3) /* matches '\n' when it should not */
 		die("regex bug confirmed: re-build git with NO_REGEX=1");
 
+	regfree(&r);
 	return 0;
 }
 
@@ -94,18 +95,20 @@ int cmd__regex(int argc, const char **argv)
 		die("failed regcomp() for pattern '%s' (%s)", pat, errbuf);
 	}
 	if (!str)
-		return 0;
+		goto cleanup;
 
 	ret = regexec(&r, str, 1, m, 0);
 	if (ret) {
 		if (silent || ret == REG_NOMATCH)
-			return ret;
+			goto cleanup;
 
 		regerror(ret, &r, errbuf, sizeof(errbuf));
 		die("failed regexec() for subject '%s' (%s)", str, errbuf);
 	}
 
-	return 0;
+cleanup:
+	regfree(&r);
+	return ret;
 usage:
 	usage("\ttest-tool regex --bug\n"
 	      "\ttest-tool regex [--silent] <pattern>\n"

t/t7812-grep-icase-non-ascii.sh

@@ -2,6 +2,7 @@
 
 test_description='grep icase on non-English locales'
 
+TEST_PASSES_SANITIZE_LEAK=true
 . ./lib-gettext.sh
 
 doalarm () {