311120 - Preferences dialog leakes 220 refcounted strings

Status: RESOLVED WORKSFORME

(Firefox :: Settings UI, defect)

Description

[Henrik Skupin [:whimboo][⌚️UTC+2]]

After stepping throught all preferences tabs I noticed a high leak count when
closing my Firefox debug build Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.9a1)
Gecko/20051004 Firefox/1.6a1

When I start Firefox with about:blank and close it immediately I've following
refcount:

nsStringStats
 => mAllocCount:          18808
 => mReallocCount:         2591
 => mFreeCount:           18807  --  LEAKED 1 !!!
 => mShareCount:          18964
 => mAdoptCount:           1643
 => mAdoptFreeCount:       1616  --  LEAKED 27 !!!

Doing the same but visiting all preferences panels the refcount is increased
impressive:

nsStringStats
 => mAllocCount:          30054
 => mReallocCount:         3152
 => mFreeCount:           29833  --  LEAKED 221 !!!
 => mShareCount:          39829
 => mAdoptCount:           2280
 => mAdoptFreeCount:       2247  --  LEAKED 33 !!!

You can reproduce it by just opening the privacy panel within the preferences.
That's enough to get the high refcount.

Comment 1

[Mike Connor [:mconnor]]

So, something is making us leak the whole window, most likely.

Comment 2

[Adam Guthrie]

Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.9a1) Gecko/20060518 Minefield/3.0a1

I can't reproduce this in a trunk debug build. I did extensive dialog opening and still only leaked 5 windows, which was what was leaked if I just opened up with homepage set to about:config and closed the browser.

Is this an issue on branch?

Comment 3

[Joey Minta]

(In reply to comment #2)
> Is this an issue on branch?
> 
WFM on branch-linux:
 => mAllocCount:          14268
 => mReallocCount:         3172
 => mFreeCount:           14263  --  LEAKED 5 !!!
 => mShareCount:          15108
 => mAdoptCount:           1787
 => mAdoptFreeCount:       1740  --  LEAKED 47 !!!

Comment 4

[Mike Connor [:mconnor]]

same thing with or without prefwindow opening?  if I'm reading that right, please resolve WFM and I'll clear the blocking flag.

Comment 5

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

Does this depend which tab in the preferences window you have?  Note that the preferences window remembers the selected tab, so you could have been hitting tab-specific code that was triggering a leak.  Did you try going through all tabs?

Comment 6

[Adam Guthrie]

Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.9a1) Gecko/20060531 Minefield/3.0a1

I just went through and tried starting up with every tab in the pref. window, (yes, this was tedious) and I still only leaked 5 strings. Granted, I did not try enabling or disabling preferences that could've been calling some other code, but if anyone wants to do this, feel free!

Comment 7

[Michael Wu [:mwu]]

I'm not seeing this on branch. mconnor, this can be removed as a blocking bug for 2.0.

Open about:blank and close.

nsStringStats
 => mAllocCount:          12221
 => mReallocCount:         2770
 => mFreeCount:           12216  --  LEAKED 5 !!!
 => mShareCount:          11515
 => mAdoptCount:           1742
 => mAdoptFreeCount:       1708  --  LEAKED 34 !!!

Open about:blank, open prefs dialog, open all tabs, close prefs dialog, close firefox.

nsStringStats
 => mAllocCount:          21351
 => mReallocCount:         3368
 => mFreeCount:           21346  --  LEAKED 5 !!!
 => mShareCount:          33383
 => mAdoptCount:           2508
 => mAdoptFreeCount:       2461  --  LEAKED 47 !!!

On trunk, open about:blank and close:

nsStringStats
 => mAllocCount:          12219
 => mReallocCount:         2023
 => mFreeCount:           12214  --  LEAKED 5 !!!
 => mShareCount:          11755
 => mAdoptCount:           1587
 => mAdoptFreeCount:       1587

open about:blank, open preferences dialog to privacy, close preferences dialog, close firefox:

nsStringStats
 => mAllocCount:          20154
 => mReallocCount:         2532
 => mFreeCount:           20148  --  LEAKED 6 !!!
 => mShareCount:          17436
 => mAdoptCount:           1861
 => mAdoptFreeCount:       1861

So.. it might still be an issue still on trunk, but it shouldn't be blocking 2.0 since it isn't an issue there.

Comment 8

[Adam Guthrie]

So mwu can reproduce this on trunk, but not in branch. He's using KDE. Henrik, were you using GNOME or KDE when you reproduced this?

Comment 9

[Henrik Skupin [:whimboo][⌚️UTC+2]]

(In reply to comment #8)
> So mwu can reproduce this on trunk, but not in branch. He's using KDE. Henrik,
> were you using GNOME or KDE when you reproduced this?

I were using KDE when I found this leak. Due to my work I had to port to Windows again, so I can't do any tests for myself at the moment. Sorry.

Comment 10

[Mike Connor [:mconnor]]

Thanks Michael/Adam!

Resolving as WFM, please file a new bug if this reappears.