diff -r a0f56d2944ca src/d_dehacked.cpp
--- a/src/d_dehacked.cpp	Mon Jan 07 00:39:28 2013 +0200
+++ b/src/d_dehacked.cpp	Sat Jan 12 14:24:10 2013 +0100
@@ -404,6 +404,10 @@
 	}
 
 	do {
+		// Prevents crashing if contents of DEHACKED lump don't end with
+		// a new line.
+		if (*PatchPt == '\0')
+			break;
 		// Ignore carriage returns
 		if (*PatchPt != '\r')
 			*str++ = *PatchPt;