From: Chris Hanson <org/chris-hanson/cph>
Date: Sat, 23 Mar 1996 06:17:00 +0000 (+0000)
Subject: Fix bug: the computed indentation could be negative, which caused
X-Git-Tag: 20090517-FFI~5639
X-Git-Url: https://birchwood-abbey.net/git?a=commitdiff_plain;h=c77d959928b53406f2ab0e9279fedd78a2cb5f8a;p=mit-scheme.git

Fix bug: the computed indentation could be negative, which caused
Scheme to die with a SIGSEGV.
---

diff --git a/v7/src/edwin/cinden.scm b/v7/src/edwin/cinden.scm
index 5582a767c..ec506d1ef 100644
--- a/v7/src/edwin/cinden.scm
+++ b/v7/src/edwin/cinden.scm
@@ -1,8 +1,8 @@
 ;;; -*-Scheme-*-
 ;;;
-;;;	$Id: cinden.scm,v 1.12 1995/02/07 23:50:20 cph Exp $
+;;;	$Id: cinden.scm,v 1.13 1996/03/23 06:17:00 cph Exp $
 ;;;
-;;;	Copyright (c) 1986, 1989-95 Massachusetts Institute of Technology
+;;;	Copyright (c) 1986, 1989-96 Massachusetts Institute of Technology
 ;;;
 ;;;	This material was developed by the Scheme project at the
 ;;;	Massachusetts Institute of Technology, Department of
@@ -126,10 +126,10 @@ This is in addition to c-continued-statement-offset."
 	   start
 	   (backward-definition-start start 1 'LIMIT))))
 	((char-match-forward #\} start)
-	 (- indentation (ref-variable c-indent-level start)))
+	 (max 0 (- indentation (ref-variable c-indent-level start))))
 	((char-match-forward #\{ start)
-	 (+ indentation (ref-variable c-brace-offset start)))
-	(else indentation)))
+	 (max 0 (+ indentation (ref-variable c-brace-offset start))))
+	(else (max 0 indentation))))
 
 (define (calculate-indentation mark parse-start)
   (let ((indent-point (line-start mark 0)))