From 4fe1673475fe2f20c2e95ce04c73ae7d190956ff Mon Sep 17 00:00:00 2001
From: Matthew Flatt <mflatt@racket-lang.org>
Date: Tue, 7 Jan 2014 10:21:38 -0700
Subject: [PATCH] fix (more) closure type tracking for a procedure with only an
 unused rest arg

Fixs the repair in fe12a32dc3

Relevant to PR 14259
---
 .../racket-test/tests/racket/optimize.rktl       | 16 ++++++++++++++++
 racket/src/racket/src/resolve.c                  | 11 +++++++++++
 2 files changed, 27 insertions(+)

diff --git a/pkgs/racket-pkgs/racket-test/tests/racket/optimize.rktl b/pkgs/racket-pkgs/racket-test/tests/racket/optimize.rktl
index ce698e0180..b4deac79d5 100644
--- a/pkgs/racket-pkgs/racket-test/tests/racket/optimize.rktl
+++ b/pkgs/racket-pkgs/racket-test/tests/racket/optimize.rktl
@@ -3207,6 +3207,22 @@
     ;; Should succeed, as opposed to a validation error:
     (eval (read (open-input-bytes (get-output-bytes o))))))
 
+(parameterize ([current-namespace (make-base-namespace)]
+               [read-on-demand-source #f]
+               [read-accept-compiled #t])
+  (let ([o (open-output-bytes)])
+    (write (compile '(module m racket/base
+                       (require racket/fixnum)
+                       (define ident (lambda (x) x))
+                       (set! ident ident)
+                       (define app (lambda (f) (f)))
+                       (set! app app)
+                       (let ([n (fxmax (length '()) 1)])
+                         (app (lambda _ (ident n))))))
+           o)
+    ;; Should succeed, as opposed to a validation error:
+    (eval (read (open-input-bytes (get-output-bytes o))))))
+
 ;; ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
 ;; Check interaciton of 3-D macros, non-empty closures, JIT, and bytecode:
 
diff --git a/racket/src/racket/src/resolve.c b/racket/src/racket/src/resolve.c
index 03faaf1737..a9bc8f71c4 100644
--- a/racket/src/racket/src/resolve.c
+++ b/racket/src/racket/src/resolve.c
@@ -1690,11 +1690,21 @@ static mzshort *allocate_boxmap(int n)
 }
 
 void scheme_boxmap_set(mzshort *boxmap, int j, int bit, int delta)
+/* assumes that existing bits are cleared */
 {
   j *= CLOS_TYPE_BITS_PER_ARG;
   boxmap[delta + (j / BITS_PER_MZSHORT)] |= ((mzshort)bit << (j & (BITS_PER_MZSHORT - 1)));
 }
 
+static void boxmap_clear(mzshort *boxmap, int j, int delta)
+{
+  mzshort v;
+  j *= CLOS_TYPE_BITS_PER_ARG;
+  v = boxmap[delta + (j / BITS_PER_MZSHORT)];
+  v ^= (v & ((mzshort)(((1 << CLOS_TYPE_BITS_PER_ARG) - 1) << (j & (BITS_PER_MZSHORT - 1)))));
+  boxmap[delta + (j / BITS_PER_MZSHORT)] = v;
+}
+
 int scheme_boxmap_get(mzshort *boxmap, int j, int delta)
 {
   j *= CLOS_TYPE_BITS_PER_ARG;
@@ -2020,6 +2030,7 @@ resolve_closure_compilation(Scheme_Object *_data, Resolve_Info *info,
       if (expanded_already) {
         /* shift type map down: */
         for (i = 0; i < closure_size; i++) {
+          boxmap_clear(closure_map, i, closure_size);
           scheme_boxmap_set(closure_map, i, scheme_boxmap_get(closure_map, i + 1, closure_size), closure_size);
         }
         SCHEME_CLOSURE_DATA_FLAGS(data) |= CLOS_HAS_TYPED_ARGS;