http: -Wdate-time warning appeared first in gcc5, not exits before

net/http/civetweb/civetweb.c

@@ -19046,9 +19046,11 @@ mg_get_system_info_impl(char *buffer, int buflen)
 	/* Build date */
 	{
 #if defined(GCC_DIAGNOSTIC)
+#if GCC_VERSION >= 50000
 #pragma GCC diagnostic push
 /* Disable bogus compiler warning -Wdate-time */
 #pragma GCC diagnostic ignored "-Wdate-time"
+#endif
 #endif
 		mg_snprintf(NULL,
 		            NULL,
@@ -19059,7 +19061,9 @@ mg_get_system_info_impl(char *buffer, int buflen)
 		            eol);
 #if defined(GCC_DIAGNOSTIC)
+#if GCC_VERSION >= 50000
 #pragma GCC diagnostic pop
+#endif
 #endif
 		system_info_length += (int)strlen(block);