From 36b9ee5cf4f03d09f167a26e787319b59de7c746 Mon Sep 17 00:00:00 2001
From: David Seguin <davidseguin@live.ca>
Date: Wed, 7 Sep 2016 23:28:50 -0400
Subject: [PATCH] Added check to rescan zlib and pthread on linux

unset ZLIB_LIBRARY and CMAKE_HAVE_PTHREAD_H to rescan those libs
when arch changes from 32 to 64 (and vis-versa). There may be a
better way to do this.
---
 CMakeLists.txt | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index a55940eff..3eb6a1927 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -274,6 +274,16 @@ endif()
 
 #### expose depends ####
 
+# check for change in arch (32<->64)
+if(UNIX)
+    GET_PROPERTY(DFHACK_CACHED_ARCH CACHE STRING PROPERTY DFHACK_BUILD_ARCH)
+    if("${DFHACK_BUILD_ARCH}" STREQUAL "${DFHACK_CACHED_ARCH}")
+        # no change
+    else()
+        unset(ZLIB_LIBRARY CACHE)
+        unset(CMAKE_HAVE_PTHREAD_H CACHE)
+    endif()
+endif()
 
 # find and make available libz
 if(NOT UNIX) # Windows