From cc8f29a1e60030dc81099c40a99a1f8731bbf114 Mon Sep 17 00:00:00 2001
From: "Salvador E. Tropea" <salvador@inti.gob.ar>
Date: Thu, 13 Oct 2016 17:51:14 -0300
Subject: [PATCH] Allow to overwrite ABCEXTERNAL from the environment. In this
 way Debian scripts can define it as berkeley-abc from the shell.

---
 Makefile | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/Makefile b/Makefile
index 4534d619e..9f16a4fb7 100644
--- a/Makefile
+++ b/Makefile
@@ -90,7 +90,7 @@ ABCMKARGS = CC="$(CXX)" CXX="$(CXX)"
 
 # set ABCEXTERNAL = <abc-command> to use an external ABC instance
 # Note: The in-tree ABC (yosys-abc) will not be installed when ABCEXTERNAL is set.
-ABCEXTERNAL =
+ABCEXTERNAL ?=
 
 define newline
 
-- 
2.30.2