0.pre7.86.flaky7.19:

	(bootstraps itself and gets through many regression tests,
		but dies in clocc-ansi-test :SECTION5-LEGACY-699)
	The obvious version of scavenging closure-over relationships
		still wanders into deleted lambdas, and when I stop
		it from wandering into deleted lambdas, the compiler
		fails in UNCONVERT-TAIL-CALLS when cross-compiling
		pprint.lisp. The problem is that a CONTINUATION-DEST
		is NIL when UNCONVERT-TAIL-CALLS is expecting it to
		be a NODE. So I looked at the description of DEST in
		DEFSTRUCT CONTINUATION, and looking at the way that the
		CONTINUATION-DEST is used in UNCONVERT-TAIL-CALLS and...
	...made UNCONVERT-TAIL-CALLS handle null values of THIS-CALL
		(treating them as "can't possibly be one of the
		matches that I'm looking for")

diff --git a/src/compiler/dfo.lisp b/src/compiler/dfo.lisp
index 325bdfa..68469c8 100644 (file)
--- a/src/compiler/dfo.lisp
+++ b/src/compiler/dfo.lisp
@@ -263,13 +263,24 @@
          (dolist (call calls)
            (let ((call-home (lambda-home call)))
              (setf res (dfo-scavenge-dependency-graph call-home res)))))
-       ;; TO DO: Scavenge closure-over relationships.
-       (values)
+       ;; Scavenge closure-over relationships: if FUN refers to a
+       ;; variable whose home lambda is not FUN, then the home lambda
+       ;; should be in the same component as FUN. (sbcl-0.6.13, and
+       ;; CMU CL, didn't do this, leading to the occasional failure
+       ;; when physenv analysis, which is local to each component,
+       ;; would bogusly conclude that a closed-over variable was
+       ;; unused and thus delete it. See e.g. cmucl-imp 2001-11-29.)
+       (dolist (var (lambda-refers-to-vars clambda))
+         (unless (null (lambda-var-refs var)) ; i.e. unless deleted
+           (let ((var-home-home (lambda-home (lambda-var-home var))))
+             (unless (eql (lambda-kind var-home-home) :deleted)
+               (setf res
+                     (dfo-scavenge-dependency-graph var-home-home res))))))
        ;; Voila.
        res)))))
 
-;;; Return true if CLAMBDA either is an XEP or has EXITS to some of its
-;;; ENTRIES.
+;;; Return true if CLAMBDA either is an XEP or has EXITS to some of
+;;; its ENTRIES.
 (defun has-xep-or-nlx (clambda)
   (declare (type clambda clambda))
   (or (eq (functional-kind clambda) :external)

diff --git a/src/compiler/locall.lisp b/src/compiler/locall.lisp
index 8cab2c5..d031161 100644 (file)
--- a/src/compiler/locall.lisp
+++ b/src/compiler/locall.lisp
@@ -861,7 +861,8 @@
   (dolist (called (lambda-calls fun))
     (dolist (ref (leaf-refs called))
       (let ((this-call (continuation-dest (node-cont ref))))
-       (when (and (node-tail-p this-call)
+       (when (and this-call
+                  (node-tail-p this-call)
                   (eq (node-home-lambda this-call) fun))
          (setf (node-tail-p this-call) nil)
          (ecase (functional-kind called)

diff --git a/version.lisp-expr b/version.lisp-expr
index f924f19..e45fbb1 100644 (file)
--- a/version.lisp-expr
+++ b/version.lisp-expr
@@ -18,4 +18,4 @@
 ;;; for internal versions, especially for internal versions off the
 ;;; main CVS branch, it gets hairier, e.g. "0.pre7.14.flaky4.13".)
 
-"0.pre7.86.flaky7.18"
+"0.pre7.86.flaky7.19"