520661 - nsDeque should handle out-of-memory better

Status: RESOLVED FIXED

(Core :: XPCOM, defect, P2)

Description

[David Baron :dbaron: (⌚️UTC-5, no longer working on Mozilla)]

Attachment: patch

peterv and I noticed this while debugging cycle collector crashes; given that the cycle collector creates nsDeque objects that require multi-megabyte allocations, this could actually affect users sometimes.

(The cycle collector, at least, handles silent failure to add to a deque just fine, in that the worst side effect would be failure to collect objects.)

I also made it use memcpy rather than copying the pointers in an array.

Comment 1

[David Baron :dbaron: (⌚️UTC-5, no longer working on Mozilla)]

http://hg.mozilla.org/mozilla-central/rev/95fb146a7337

Comment 2

[David Baron :dbaron: (⌚️UTC-5, no longer working on Mozilla)]

Comment on attachment 404717 [details] [diff] [review]
patch

Want to get this in on the chance that it's responsible for some of the cycle collector crashes.

Comment 3

[David Baron :dbaron: (⌚️UTC-5, no longer working on Mozilla)]

http://hg.mozilla.org/releases/mozilla-1.9.2/rev/d2a814272746

Comment 4

[Daniel Veditz [:dveditz] back 2026-04-08]

Comment on attachment 404717 [details] [diff] [review]
patch

>  * @return  capacity of the deque
>  *          If the deque did not grow,
>  *          and you knew its capacity beforehand,
>  *          then this would be a way to indicate the failure.
>  */
>-PRInt32 nsDeque::GrowCapacity() {
>+PRBool nsDeque::GrowCapacity() {

Could you fix up the comment to match the new return value? Thanks

Approved for 1.9.1.5, a=dveditz for release-drivers

Comment 5

[David Baron :dbaron: (⌚️UTC-5, no longer working on Mozilla)]

Comment fix landed:
http://hg.mozilla.org/mozilla-central/rev/5edfb6dce6e9
http://hg.mozilla.org/releases/mozilla-1.9.2/rev/642185ee31d3

Comment 6

[David Baron :dbaron: (⌚️UTC-5, no longer working on Mozilla)]

http://hg.mozilla.org/releases/mozilla-1.9.1/rev/b3078ea11041
(with comment fix rolled in)