diff --git a/include/rapidjson/internal/regex.h b/include/rapidjson/internal/regex.h
index 6d110bd..e1a2faa 100644
--- a/include/rapidjson/internal/regex.h
+++ b/include/rapidjson/internal/regex.h
@@ -29,8 +29,10 @@ RAPIDJSON_DIAG_OFF(implicit-fallthrough)
 #ifdef __GNUC__
 RAPIDJSON_DIAG_PUSH
 RAPIDJSON_DIAG_OFF(effc++)
+#if __GNUC__ >= 7
 RAPIDJSON_DIAG_OFF(implicit-fallthrough)
 #endif
+#endif
 
 #ifdef _MSC_VER
 RAPIDJSON_DIAG_PUSH