summaryrefslogtreecommitdiff
path: root/module/language/tree-il/cse.scm
diff options
context:
space:
mode:
authorLudovic Courtès <ludo@gnu.org>2012-11-21 23:51:16 +0100
committerLudovic Courtès <ludo@gnu.org>2012-11-21 23:51:16 +0100
commit2c7b7e0f214be5ec5184949a94209668775f60bc (patch)
tree031e9ee7a425c91bd562e4b914dd3fa5c5d334aa /module/language/tree-il/cse.scm
parent2d37a9349404c3161d89967c014cbaa1a28e59ea (diff)
downloadguile-2c7b7e0f214be5ec5184949a94209668775f60bc.tar.gz
cse: Fix out-of-bounds access to the database.
Fixes <http://bugs.gnu.org/12883>. * module/language/tree-il/cse.scm (cse)[find-dominating-lexical]: Fix computation of the last argument passed to `unroll'. Patch by Stefan Israelsson Tampe <stefan.itampe@gmail.com>. * test-suite/tests/cse.test ("cse")["http://bugs.gnu.org/12883"]: New test.
Diffstat (limited to 'module/language/tree-il/cse.scm')
-rw-r--r--module/language/tree-il/cse.scm9
1 files changed, 5 insertions, 4 deletions
diff --git a/module/language/tree-il/cse.scm b/module/language/tree-il/cse.scm
index b8e722967..d8c7e3fc9 100644
--- a/module/language/tree-il/cse.scm
+++ b/module/language/tree-il/cse.scm
@@ -330,10 +330,11 @@
(and (< n env-len)
(match (vlist-ref env n)
((#(exp* name sym db-len*) . h*)
- (and (unroll db m (- db-len db-len*))
- (if (and (= h h*) (tree-il=? exp* exp))
- (make-lexical-ref (tree-il-src exp) name sym)
- (lp (1+ n) (- db-len db-len*))))))))))))
+ (let ((niter (- (- db-len db-len*) m)))
+ (and (unroll db m niter)
+ (if (and (= h h*) (tree-il=? exp* exp))
+ (make-lexical-ref (tree-il-src exp) name sym)
+ (lp (1+ n) (- db-len db-len*)))))))))))))
(define (lookup-lexical sym env)
(let ((env-len (vlist-length env)))