From a53a7d6e6a44b74a5426cb906e2d9e149bd23e75 Mon Sep 17 00:00:00 2001
From: Gael Guennebaud <g.gael@free.fr>
Date: Thu, 17 Feb 2011 18:19:28 +0100
Subject: [PATCH] use C linkage for umfpack (might fix some linking issues)

---
 unsupported/Eigen/UmfPackSupport | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/unsupported/Eigen/UmfPackSupport b/unsupported/Eigen/UmfPackSupport
index 82d1d4fef..c49f20145 100644
--- a/unsupported/Eigen/UmfPackSupport
+++ b/unsupported/Eigen/UmfPackSupport
@@ -5,7 +5,9 @@
 
 #include "../../Eigen/src/Core/util/DisableMSVCWarnings.h"
 
+extern "C" {
 #include <umfpack.h>
+}
 
 namespace Eigen {