Oh, btw, I forgot to mention, that I was experience that bug even in 5.0.1 (and, maybe, even earlier).

Please add the backtrace using the "Add an attachment" link on this page.

Unfortunatelly, bugzilla throws 500 error when I trying to do so.
I guess, it's due to size of the log (6.7M, since there is very long loop between some functions).

Is it another way to upload it somewhere? Or increase limit/fix bugzilla somehow?

If there is a loop, it should be possible to compress it using 'xz'.

Created attachment 108325 [details]
ktorrent.crash.log.xz

Here it is

Same issue here, on Arch linux, getting it for quite a while now. I think it has been there since ktorrent moved to Plasma 5.

Just a note, when starting ktorrent next time, the downloading order of the file has changed to what was selected (and works flawlessly, automatically changing file download priority as they download).

I've the same issue in KDE neon.

Git commit 722c21e56d9e55d69fb6ab4b75847b577cb197fd by Andrius Štikonas, on behalf of Jacopo Guderzo.
Committed on 30/01/2018 at 14:48.
Pushed by stikonas into branch 'master'.

Fix crash when changing file download order

DownloadOrderDialog::commitDownloadOrder() is connected to the accepted
signal, calling accept() inside it causes a loop.

Differential Revision: https://phabricator.kde.org/D10192

M  +0    -1    plugins/downloadorder/downloadorderdialog.cpp

https://commits.kde.org/ktorrent/722c21e56d9e55d69fb6ab4b75847b577cb197fd

Git commit 623c75b86840eda42609a2319e6a101c12fe347f by Andrius Štikonas, on behalf of Jacopo Guderzo.
Committed on 28/08/2018 at 19:27.
Pushed by stikonas into branch '5.1'.

Fix crash when changing file download order

DownloadOrderDialog::commitDownloadOrder() is connected to the accepted
signal, calling accept() inside it causes a loop.

Differential Revision: https://phabricator.kde.org/D10192

M  +0    -1    plugins/downloadorder/downloadorderdialog.cpp

https://commits.kde.org/ktorrent/623c75b86840eda42609a2319e6a101c12fe347f