I can't seem to pinpoint the cause

common/debugging/makefile

@@ -1,5 +1,5 @@
 #config
-INCLUDES+=.
+INCLUDES+=. ../map
 LIBS+=
 CXXFLAGS+=-std=c++11 $(addprefix -I,$(INCLUDES))
 

common/debugging/region_checksum.cpp

@@ -0,0 +1,34 @@
+/* Copyright: (c) Kayne Ruse 2013-2015
+ * 
+ * This software is provided 'as-is', without any express or implied
+ * warranty. In no event will the authors be held liable for any damages
+ * arising from the use of this software.
+ * 
+ * Permission is granted to anyone to use this software for any purpose,
+ * including commercial applications, and to alter it and redistribute it
+ * freely, subject to the following restrictions:
+ * 
+ * 1. The origin of this software must not be misrepresented; you must not
+ * claim that you wrote the original software. If you use this software
+ * in a product, an acknowledgment in the product documentation would be
+ * appreciated but is not required.
+ * 
+ * 2. Altered source versions must be plainly marked as such, and must not be
+ * misrepresented as being the original software.
+ * 
+ * 3. This notice may not be removed or altered from any source
+ * distribution.
+*/
+#include "region_checksum.hpp"
+
+int debugRegionSum(Region* const region) {
+	int sum = 0;
+	for(int i = 0; i < REGION_WIDTH; i++) {
+		for (int j = 0; j < REGION_HEIGHT; j++) {
+			for (int k = 0; k < REGION_DEPTH; k++) {
+				sum += region->GetTile(i, j, k);
+			}
+		}
+	}
+	return sum;
+}

common/debugging/region_checksum.hpp

@@ -0,0 +1,30 @@
+/* Copyright: (c) Kayne Ruse 2013-2015
+ * 
+ * This software is provided 'as-is', without any express or implied
+ * warranty. In no event will the authors be held liable for any damages
+ * arising from the use of this software.
+ * 
+ * Permission is granted to anyone to use this software for any purpose,
+ * including commercial applications, and to alter it and redistribute it
+ * freely, subject to the following restrictions:
+ * 
+ * 1. The origin of this software must not be misrepresented; you must not
+ * claim that you wrote the original software. If you use this software
+ * in a product, an acknowledgment in the product documentation would be
+ * appreciated but is not required.
+ * 
+ * 2. Altered source versions must be plainly marked as such, and must not be
+ * misrepresented as being the original software.
+ * 
+ * 3. This notice may not be removed or altered from any source
+ * distribution.
+*/
+#ifndef REGIONCHECKSUM_HPP_
+#define REGIONCHECKSUM_HPP_
+
+#include "region.hpp"
+
+//fails if the result is 0
+int debugRegionSum(Region* const);
+
+#endif

common/map/makefile

@@ -1,5 +1,5 @@
 #config
-INCLUDES+=. ../utilities
+INCLUDES+=. ../debugging ../utilities
 LIBS+=
 CXXFLAGS+=-std=c++11 $(addprefix -I,$(INCLUDES))
 

common/map/region.cpp

@@ -25,6 +25,8 @@
 #include <cstring>
 #include <stdexcept>
 
+#include <iostream>
+
 int snapToBase(int base, int x) {
 	return floor((double)x / base) * base;
 }
@@ -39,6 +41,9 @@ Region::Region(int argX, int argY): x(argX), y(argY) {
 Region::Region(Region const& rhs): x(rhs.x), y(rhs.y) {
 	memcpy(tiles, rhs.tiles, REGION_WIDTH*REGION_HEIGHT*REGION_DEPTH*sizeof(type_t));
 	solid = rhs.solid;
+
+	//debugging
+	std::cout << "Moved: (" << x << ", " << y << "): " << int(***tiles) << ", " << int(***rhs.tiles) << std::endl;
 }
 
 Region::type_t Region::SetTile(int x, int y, int z, type_t v) {

common/map/region_pager_base.cpp

@@ -21,6 +21,8 @@
 */
 #include "region_pager_base.hpp"
 
+#include "region_checksum.hpp"
+
 #include <stdexcept>
 #include <algorithm>
 
@@ -70,7 +72,11 @@ Region* RegionPagerBase::FindRegion(int x, int y) {
 }
 
 Region* RegionPagerBase::PushRegion(Region* const ptr) {
+	//BUG: Lists seem to not work properly
 	regionList.push_front(*ptr);
+	if (debugRegionSum(&regionList.front())) {
+		throw(std::runtime_error("Checksum fail; RegionPagerBase::PushRegion()"));
+	}
 	return &regionList.front();
 }