some newfangled gcc found these 
array out-of-bounds references


Reference: /n/sources/patch/applied/old-n-buggy
Date: Sat May 10 19:25:54 CES 2008
Signed-off-by: rsc@swtch.com

--- /sys/src/cmd/eqn/main.c	Sat May 10 19:25:42 2008
+++ /sys/src/cmd/eqn/main.c	Sat May 10 19:25:41 2008
@@ -4,7 +4,7 @@
 
 char *version = "version Oct 24, 1991";
 
-char	in[MAXLINE];	/* input buffer */
+char	in[MAXLINE+1];	/* input buffer */
 int	noeqn;
 char	*cmdname;
 
--- /sys/src/cmd/jpg/readgif.c	Sat May 10 19:25:43 2008
+++ /sys/src/cmd/jpg/readgif.c	Sat May 10 19:25:42 2008
@@ -351,8 +351,10 @@
 	if(hsize>0 && Bread(h->fd, h->buf, hsize) != hsize)
 		giferror(h, extreaderr);
 	if(!hasdata){
-		if(h->buf[hsize-1] != 0)
-			giferror(h, "ReadGIF: bad extension format");
+		/*
+		 * This code used to check h->buf[hsize-1] != 0
+		 * and giferror if so, but if !hasdata, hsize == 0.
+		 */
 		return;
 	}
 
--- /sys/src/cmd/tapefs/v6fs.c	Sat May 10 19:25:43 2008
+++ /sys/src/cmd/tapefs/v6fs.c	Sat May 10 19:25:43 2008
@@ -85,7 +85,7 @@
 			continue;
 		f = iget(ino);
 		strncpy(name, dp->name, V6NAMELEN);
-		name[V6NAMELEN+1] = '\0';
+		name[V6NAMELEN] = '\0';
 		f.name = name;
 		popfile(r, f);
 	}
--- /sys/src/cmd/tapefs/v10fs.c	Sat May 10 19:25:44 2008
+++ /sys/src/cmd/tapefs/v10fs.c	Sat May 10 19:25:43 2008
@@ -90,7 +90,7 @@
 			continue;
 		f = iget(ino);
 		strncpy(name, dp->name, VNAMELEN);
-		name[VNAMELEN+1] = '\0';
+		name[VNAMELEN] = '\0';
 		f.name = name;
 		popfile(r, f);
 	}
--- /sys/src/cmd/tapefs/32vfs.c	Sat May 10 19:25:44 2008
+++ /sys/src/cmd/tapefs/32vfs.c	Sat May 10 19:25:44 2008
@@ -93,7 +93,7 @@
 			continue;
 		f = iget(ino);
 		strncpy(name, dp->name, VNAMELEN);
-		name[VNAMELEN+1] = '\0';
+		name[VNAMELEN] = '\0';
 		f.name = name;
 		popfile(r, f);
 	}
--- /sys/src/cmd/troff/t10.c	Sat May 10 19:25:45 2008
+++ /sys/src/cmd/troff/t10.c	Sat May 10 19:25:44 2008
@@ -77,7 +77,7 @@
 	ics = EM;	/* insertion character space */
 	for (i = 0; i < (NTAB - 1) && DTAB * (i + 1) < TABMASK; i++)
 		tabtab[i] = DTAB * (i + 1);
-	tabtab[NTAB] = 0;
+	tabtab[NTAB-1] = 0;
 	pl = 11 * INCH;			/* paper length */
 	po = PO;		/* page offset */
 	spacesz = SS;