From 1fc6208ec05af672c7c6b7973b0eba1295bca5f4 Mon Sep 17 00:00:00 2001
From: Clifford Wolf <clifford@clifford.at>
Date: Wed, 15 Oct 2014 01:18:31 +0200
Subject: [PATCH] Check for _YOSYS_ in yosys.h

---
 kernel/yosys.h | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/kernel/yosys.h b/kernel/yosys.h
index 83230cbfb..239146d77 100644
--- a/kernel/yosys.h
+++ b/kernel/yosys.h
@@ -58,6 +58,12 @@
 #include <string.h>
 #include <stdio.h>
 
+#ifndef _YOSYS_
+#  error It looks like you are trying to build Yosys with the config defines set. \
+         When building Yosys with a custom make system, make sure you set all the \
+	 defines the Yosys Makefile would set for your build configuration.
+#endif
+
 #ifdef YOSYS_ENABLE_TCL
 #  include <tcl.h>
 #endif
-- 
2.30.2