[Qt-interest] qmutex unlock - application waits?

[Gabriel M. Beddingfield]

On Thu, 27 May 2010, caius ligarius wrote:

>> I see something strange happening in my application. When I try to select
>> QComboBox item in my UI it just waits or freezes for a few seconds and
>> doesn't let me do anything. After pausing the code in run-time I noticed
>> that the app is getting stuck in void QMutex::unlock() function.
[snip]
>>
>> To reproduce this problem randomly keep selecting items from the combo-box
>> (top right side) and eventually it will get stuck for a few seconds in
>> the QMutex::unlock() function.

I built with qmake on windows XP (qt 4.5.3).  Not sure if I 
am able to reproduce it.

1. If I always click on the little arrow icon at the right,
    it never pauses.

2. If I click on the text, it /usually/ will pull down the
    box to select something... but /sometimes/ will pause
    briefly.  It's never really long enough to see if the
    whole UI is locked up or not.

I get the same behavior when I do 'Preview' on the form in 
Qt Designer.

-gabriel