[Development] Backporting the "stop unloading plugins" change to 5.6

[Sergio Martins]

On 2016-10-12 20:59, Thiago Macieira wrote:
> Hello
> 
> We've got a number of issues that got fixed in 5.7 by the change that 
> made
> QFactoryLoader stop unloading plugins (notably, the Network Manager 
> bearer
> plugin). Given that QtDBus in 5.6 is now heavily threaded, a number of 
> new
> issues have cropped up. I've managed to fix some, but reports from 
> Ubuntu
> developers indicate the latest fix only uncovered the next issue.

Hi,


More importantly, this also solves all the QStringLiteral related 
crashes we've been seeing.
We need this in 5.6, but it's too big a behaviour change for an LTS 
release. We need at least a variable to turn it on/off.


Suggestion which me and peppe discussed:

Make it opt-in in 5.6.3 and write in the ChangeLog that there will be a 
behaviour change in 5.6.4.
Make it opt-out in 5.6.4 (bringing it on-par with 5.8).

This gives the user a pre-warning of 3 months, it can still be turned 
off and fixes many crashes.




Regards,
-- 
Sérgio Martins | sergio.martins at kdab.com | Senior Software Engineer
Klarälvdalens Datakonsult AB, a KDAB Group company
Tel: Sweden (HQ) +46-563-540090, USA +1-866-777-KDAB(5322)
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