[PATCH] bdiff.c: use unsigned arithmetic for hash computation

[Markus F.X.J. Oberhumer]

# HG changeset patch
# User Markus F.X.J. Oberhumer <markus at oberhumer.com>
# Date 1300844003 -3600
# Node ID 4a93cf659875e42c736a7b76ad0397cc8e96b90e
# Parent  5828a08f0eb3155e40f6838fa2e557b7fa3cccc5
bdiff.c: use unsigned arithmetic for hash computation

Signed integer overflow is undefined in C.

diff --git a/mercurial/bdiff.c b/mercurial/bdiff.c
--- a/mercurial/bdiff.c
+++ b/mercurial/bdiff.c
@@ -65,7 +65,8 @@
 
 static int splitlines(const char *a, int len, struct line **lr)
 {
-	int h, i;
+	unsigned h;
+	int i;
 	const char *p, *b = a;
 	const char * const plast = a + len - 1;
 	struct line *l;
@@ -98,7 +99,8 @@
 	}
 
 	/* set up a sentinel */
-	l->h = l->len = 0;
+	l->h = 0;
+	l->len = 0;
 	l->l = a + len;
 	return i - 1;
 }