From 933e3c14b581f1449b0b15c280daa25bfa8962dd Mon Sep 17 00:00:00 2001
From: Matthew Flatt <mflatt@racket-lang.org>
Date: Sun, 28 Oct 2018 18:50:56 -0600
Subject: [PATCH] bytecode: fix "preserves marks" annotation w.r.t
 call/immediate-mark

A function that uses `call-with-immediate-continuation-mark` in tail
position should not be flagged as "preserves marks", because the JIT
needs to bump the mark stack if the function is called in non-tail
position.

Closes #2333
---
 .../tests/racket/optimize.rktl                | 36 +++++++++++++++++++
 racket/src/racket/src/optimize.c              |  2 ++
 2 files changed, 38 insertions(+)

diff --git a/pkgs/racket-test-core/tests/racket/optimize.rktl b/pkgs/racket-test-core/tests/racket/optimize.rktl
index 78aede26e2..a862deec57 100644
--- a/pkgs/racket-test-core/tests/racket/optimize.rktl
+++ b/pkgs/racket-test-core/tests/racket/optimize.rktl
@@ -6371,4 +6371,40 @@
 
 ;; ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
 
+(module optimizes-to-with-immediate-continuation-mark-in-noninlined racket/base
+  (define (call/icm proc)
+    (call-with-immediate-continuation-mark
+     'x
+     (lambda (v)
+       ;; The constant '(1 2 3) currently prevents inlining
+       (if (proc '(1 2 3))
+           (proc v)
+           #f))))
+
+  (define (call/cm proc)
+    (if (zero? (random 1))
+        (with-continuation-mark
+         'x 'y
+         (proc))
+        ;; disable inline:
+        '(3 4 5)))
+
+  (define result
+    (let ([in? #f]
+          [result #f])
+      (call/cm
+       (lambda ()
+         (set! in? #t)
+         (call/icm
+          (lambda (v)
+            (set! result v)))
+         (set! in? #f)))
+      result))
+
+  (provide result))
+
+(test #f dynamic-require ''optimizes-to-with-immediate-continuation-mark-in-noninlined 'result)
+
+;; ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+
 (report-errs)
diff --git a/racket/src/racket/src/optimize.c b/racket/src/racket/src/optimize.c
index b79e9a992d..150b5564bf 100644
--- a/racket/src/racket/src/optimize.c
+++ b/racket/src/racket/src/optimize.c
@@ -6539,6 +6539,8 @@ with_immed_mark_optimize(Scheme_Object *data, Optimize_Info *info, int context)
   wcm->val = val;
   SCHEME_CDR(wcm->body) = body;
 
+  info->preserves_marks = 0;
+
   return data;
 }