0.7.3.6:

[sbcl.git] / src / compiler / ir1util.lisp

diff --git a/src/compiler/ir1util.lisp b/src/compiler/ir1util.lisp
index 2e1d354..df17ebd 100644 (file)
--- a/src/compiler/ir1util.lisp
+++ b/src/compiler/ir1util.lisp
@@ -877,7 +877,14 @@
        (reoptimize-continuation cont)))
 
   (dolist (b (block-pred block))
-    (unlink-blocks b block))
+    (unlink-blocks b block)
+    ;; In bug 147 the almost-all-blocks-have-a-successor invariant was
+    ;; broken when successors were deleted without setting the
+    ;; BLOCK-DELETE-P flags of their predececessors. Make sure that
+    ;; doesn't happen again.
+    (aver (not (and (null (block-succ b))
+                    (not (block-delete-p b))
+                    (not (eq b (component-head (block-component b))))))))
   (dolist (b (block-succ block))
     (unlink-blocks block b))