Re: SIGSEGV from qwt3diodummy constructor

[Andreas H. <an...@xs...>]

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Hi Micha!

Thanks for your reply!

Micha Bieber schrieb:
|>I am not too familiar with qwt_plot3d and have no experience with labplot,
|>but the type of error looks to me like a typical mismatch of different Qt
|>versions.
|
|
| Perhaps true, but I'll do my guess work too.
| I've introduced the dummy variable in the past, because I received the
| same kind of crash when producing a qwt3d Windows dll in VC6 _without_
| the variable declared. The IO object is a singleton, created on the fly

oh... :-(

| inside 'static Container& wlist()' and I suspect something goes wrong here
| with global object destruction.
| I plan to release a version of qwt3d this weekend and will make an
| attempt again to understand what happens when it comes to dll's.
| I don't like this specific kind of uncertainty (or my missing knowledge)
| anyway, so its a good time to delve in again...
|

Very true.

By removing the variable I managed to eliminate the crash,
but I still do not know why the crash happens in the first
place and that makes me nervous.

There are Linux systems out there where the crash does not
happen at all. And as far as I know there are at least
three different Linux distributions (Slackware as the most
prominent amongst them) where the crash occurs.

And it also seems to be dependent on the application:
for me, the crash occurs with LabPlot only, while the
qwtplot3d example applications like simpleplot or mesh2
work just fine, even with the qwt3diodummy variable in
place. I have yet to find a simple example application
where I can reproduce the problem. This is weird!

- - andreas

- --
Andreas Haumer                     | mailto:an...@xs...
*x Software + Systeme              | http://www.xss.co.at/
Karmarschgasse 51/2/20             | Tel: +43-1-6060114-0
A-1100 Vienna, Austria             | Fax: +43-1-6060114-71
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