From 9d6f0e96ba3fca6c611f463e7172f00a32b61a06 Mon Sep 17 00:00:00 2001
From: Matthew Flatt <mflatt@racket-lang.org>
Date: Thu, 26 Jul 2012 16:31:17 -0600
Subject: [PATCH] fix for bytecode validator

Fix tchecking for a rest argument to a function that
is lifted by closure conversion so that one of its
arguments is a mutable local variable's location.

Also reject bytecode that would pass too many arguments
to a lifted function, since that would trigger an arity
error that might try to use a location as a value.

Merge to v5.3
---
 collects/tests/racket/optimize.rktl | 20 ++++++++++++++++++++
 src/racket/src/validate.c           |  9 +++++++--
 2 files changed, 27 insertions(+), 2 deletions(-)

diff --git a/collects/tests/racket/optimize.rktl b/collects/tests/racket/optimize.rktl
index 50e486183c..44a7346689 100644
--- a/collects/tests/racket/optimize.rktl
+++ b/collects/tests/racket/optimize.rktl
@@ -2123,6 +2123,26 @@
   (parse-string "()"))
 (err/rt-test (do-test-of-lift-fixpoint) exn:fail?)
 
+;; ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+;; generate byecode with a lifted function that has
+;; a boxed argument and rest args, to test that case
+;; of the validator
+
+(parameterize ([current-namespace (make-base-namespace)])
+  (define o (open-output-bytes))
+  (write
+   (compile
+    '(lambda (x)
+       (define (g . y) (if (zero? (random 1))
+                           (reverse (cons x y))
+                           (g y y y y y y y y y)))
+       (set! x x)
+       (g 12 13)))
+   o)
+  (test '(13 12 10)
+        (parameterize ([read-accept-compiled #t])
+          (eval (read (open-input-bytes (get-output-bytes o)))))
+        10))
 
 ;; ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
 
diff --git a/src/racket/src/validate.c b/src/racket/src/validate.c
index 7d006d2edb..18d0372fc3 100644
--- a/src/racket/src/validate.c
+++ b/src/racket/src/validate.c
@@ -242,8 +242,9 @@ static void define_values_validate(Scheme_Object *data, Mz_CPort *port,
         if (SCHEME_CLOSURE_DATA_FLAGS(data) & CLOS_HAS_TYPED_ARGS) {
           int sz;
           sz = data->num_params;
-          new_a = MALLOC_N_ATOMIC(mzshort, (sz + 1));
+          new_a = MALLOC_N_ATOMIC(mzshort, (sz + 2));
           new_a[0] = -sz;
+          new_a[sz+1] = !!(SCHEME_CLOSURE_DATA_FLAGS(data) & CLOS_HAS_REST);
           for (i = 0; i < sz; i++) {
             int bit = ((mzshort)1 << ((2 * i) & (BITS_PER_MZSHORT - 1)));
             if (data->closure_map[data->closure_size + ((2 * i) / BITS_PER_MZSHORT)] & bit)
@@ -623,7 +624,11 @@ int scheme_validate_rator_wants_box(Scheme_Object *app_rator, int pos,
             /* try again */
             p = a[1];
           } else {
-            return a[pos + 1];
+            if (pos >= -a[0]) {
+              /* last slot indicates whether rest args are allowed */
+              return (a[-a[0]+1] ? hope : !hope);
+            } else
+              return a[pos + 1];
           }
         } else
           return 0;