diff --git a/format.c b/format.c
index d4af471d..d0090bc8 100644
--- a/format.c
+++ b/format.c
@@ -455,14 +455,18 @@ format_job_tidy(struct format_job_tree *jobs, int force)
 }
 
 /* Work around needless -Wformat-nonliteral gcc warning. */
+#ifdef __GNUC__
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wformat-nonliteral"
+#endif
 static size_t
 format_strftime(char *s, size_t max, const char *fmt, const struct tm *tm)
 {
-#pragma GCC diagnostic push
-#pragma GCC diagnostic ignored "-Wformat-nonliteral"
 	return (strftime(s, max, fmt, tm));
-#pragma GCC diagnostic pop
 }
+#ifdef __GNUC__
+#pragma GCC diagnostic pop
+#endif
 
 /* Tidy old jobs for all clients. */
 void