From b56c994b721f7cb5c5bcf09c5d695d4ae07d3052 Mon Sep 17 00:00:00 2001
From: Simon Tatham <anakin@pobox.com>
Date: Sat, 11 Dec 2021 13:56:12 +0000
Subject: [PATCH] Pattern: fix a compile warning about memset bounds.

The argument to memset was being taken from an int variable that not
all compilers are able to prove is non-negative. Adding an assert
convinces them.
---
 pattern.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/pattern.c b/pattern.c
index 278bc33..7c00bf9 100644
--- a/pattern.c
+++ b/pattern.c
@@ -439,6 +439,8 @@ static bool do_row(unsigned char *known, unsigned char *deduced,
     int rowlen, i, freespace;
     bool done_any;
 
+    assert(len >= 0);   /* avoid compile warnings about the memsets below */
+
     freespace = len+1;
     for (rowlen = 0; data[rowlen]; rowlen++) {
 	minpos_done[rowlen] = minpos_ok[rowlen] = len - 1;