[Guile-commits] 03/03: Fix intmap-add! transient bug

[Andy Wingo]

wingo pushed a commit to branch master
in repository guile.

commit 0f082bd3f7ad4854333728c6d0f71ef7df1fbec3
Author: Andy Wingo <address@hidden>
Date:   Fri May 8 14:09:40 2015 +0200

    Fix intmap-add! transient bug
    
    * module/language/cps/intmap.scm (intmap-add!): Fix a bug creating a
      transient branch out of a persistent branch.
---
 module/language/cps/intmap.scm |    5 ++++-
 1 files changed, 4 insertions(+), 1 deletions(-)

diff --git a/module/language/cps/intmap.scm b/module/language/cps/intmap.scm
index 146b550..9081f33 100644
--- a/module/language/cps/intmap.scm
+++ b/module/language/cps/intmap.scm
@@ -174,7 +174,10 @@
         (#f (let ((v (new-branch edit)))
               (vector-set! root idx v)
               v))
-        (v (writable-branch v edit)))))
+        (v (let ((v* (writable-branch v edit)))
+             (unless (eq? v v*)
+               (vector-set! root idx v*))
+             v*)))))
   (define (adjoin! i shift root)
     (let* ((shift (- shift *branch-bits*))
            (idx (logand (ash i (- shift)) *branch-mask*)))