From 72bd3e28ed2471daad12125b014d90d2bb300a86 Mon Sep 17 00:00:00 2001
From: Monster Iestyn <iestynjealous@ntlworld.com>
Date: Tue, 31 Jan 2017 22:10:31 +0000
Subject: [PATCH] Fix sprtopscreen from getting integer overflows once and for
 all in R_DrawRepeatMaskedColumn

Fixes TD's terminal from freezing the game this time, oh boy
---
 src/r_segs.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/src/r_segs.c b/src/r_segs.c
index 3059860cf..502ff3304 100644
--- a/src/r_segs.c
+++ b/src/r_segs.c
@@ -708,7 +708,10 @@ static void R_DrawRepeatMaskedColumn(column_t *col)
 {
 	while (sprtopscreen < sprbotscreen) {
 		R_DrawMaskedColumn(col);
-		sprtopscreen += dc_texheight*spryscale;
+		if ((INT64)sprtopscreen + dc_texheight*spryscale > (INT64)INT32_MAX) // prevent overflow
+			sprtopscreen = INT32_MAX;
+		else
+			sprtopscreen += dc_texheight*spryscale;
 	}
 }