771027 - Assertion failure: isObject(), at ../../jsapi.h:474 or Opt Crash [@ js_IteratorMore]

Status: RESOLVED FIXED

(Core :: JavaScript Engine, defect)

Description

[Christian Holler (:decoder)]

The following test asserts/crashes on mozilla-central revision b6aa44d8f11f (options -m -n -a):


Array.prototype.iterator = (function() { { while(0) function Uint8ClampedArray() {  } } });
assertEq(Set(["testing", "testing", 123]).size(), 2);


Opt-crash trace:

==35441== Invalid read of size 4
==35441==    at 0x80CE74F: js_IteratorMore(JSContext*, JS::Handle<JSObject*>, JS::Value*) (jsiter.cpp:1762)
==35441==    by 0xFFFFFF81: ???
==35441==  Address 0x0 is not stack'd, malloc'd or (recently) free'd

Comment 1

[Jesse Ruderman]

The first bad revision is:
changeset:   cb49c3730a97
user:        Jason Orendorff
date:        Tue Jul 03 16:34:56 2012 -0500
summary:     Bug 725907 - for-of improvements, part 2: Make for-of loops just call .iterator() instead of using the magic iteratorObject hook with an extra flag. r=bhackett.

The first good revision is:
changeset:   aadf6091245b
user:        Ehsan Akhgari
date:        Wed Jul 04 19:26:20 2012 -0400
summary:     Backout changeset cb49c3730a97 (bug 725907 part 2) under the suspicion of breaking Linux32 mochitest-chrome without framepointers

Comment 2

[Jason Orendorff [:jorendorff]]

Reproduced. Even without -m -n -a. Taking.

Comment 3

[Jason Orendorff [:jorendorff]]

Attachment: v1

Yup. Easy fix. Right on, fuzzers.

Comment 4

[Gary Kwong [:gkw] [:nth10sd] (NOT official MoCo now)]

(In reply to Jason Orendorff [:jorendorff] from comment #3)
> Created attachment 639693 [details] [diff] [review]
> v1
> 
> Yup. Easy fix. Right on, fuzzers.

Unfortunately, I think the patch now has a little bit of bitrot to land on mozilla-inbound.

Comment 5

[Jason Orendorff [:jorendorff]]

No worries. The Map/Set iterators were backed out due to unrelated brain damage, but when I reland them, I'll land this fix along with them.

Comment 6

[Ed Morley [:emorley]]

https://hg.mozilla.org/mozilla-central/rev/a04de3c84630

Comment 7

[Christian Holler (:decoder)]

Automatically extracted testcase for this bug was committed:

https://hg.mozilla.org/mozilla-central/rev/efaf8960a929