config.h is a local header not a system header.
--- src/core/platform.h.orig	2018-03-31 01:05:50.000000000 -0500
+++ src/core/platform.h	2021-05-09 10:23:15.000000000 -0500
@@ -34,7 +34,7 @@
 //
 
 #ifdef HAVE_CONFIG_H
-#include <config.h>
+#include "config.h"
 #endif
 
 #ifndef __PLATFORM_H