MobileRead Forums - View Single Post - Sigil "not responding

KevinH · 04-07-2017, 03:38 PM

Interesting. Thanks for the new dmp file. I have passed it on to DiapDealer and so hopefully he will be able to get a backtrace from it.

By studying the current code I have found one potential bug in that drawing the right side Preview window is actually done asynchronously but the current code does not wait for the proper load finished signal from the QWebView.

This can result in reentering the routine that draws that Preview prematurely and that might cause memory corruption. A similar bug was fixed in the ViewEditor code as it caused segfaults in Preview Window and BookView but I fixed that long ago.

I have no idea if this is the root of the problem or not but it certainly can not hurt to fix it to work as it should. I will include these changes into master so that they are fixed in the next release.

BTW: There are many open bug reports at Qt that show almost the exact same backtraces and one hangs indefinitely and one crashes on Windows. Both are related to QFileIconProvider and thumbnails.

For the record, here are two of them that are not closed yet and appear similar to what you are seeing.

https://bugreports.qt.io/browse/QTBUG-45298
https://bugreports.qt.io/browse/QTCREATORBUG-13697?

There are others.

Thanks for sticking this out so we can figure out a way to stop it form happening and improve Sigil.

04-07-2017, 03:38 PM	#112
KevinH Sigil Developer Posts: 8,951 Karma: 6361444 Join Date: Nov 2009 Device: many	Interesting. Thanks for the new dmp file. I have passed it on to DiapDealer and so hopefully he will be able to get a backtrace from it. By studying the current code I have found one potential bug in that drawing the right side Preview window is actually done asynchronously but the current code does not wait for the proper load finished signal from the QWebView. This can result in reentering the routine that draws that Preview prematurely and that might cause memory corruption. A similar bug was fixed in the ViewEditor code as it caused segfaults in Preview Window and BookView but I fixed that long ago. I have no idea if this is the root of the problem or not but it certainly can not hurt to fix it to work as it should. I will include these changes into master so that they are fixed in the next release. BTW: There are many open bug reports at Qt that show almost the exact same backtraces and one hangs indefinitely and one crashes on Windows. Both are related to QFileIconProvider and thumbnails. For the record, here are two of them that are not closed yet and appear similar to what you are seeing. https://bugreports.qt.io/browse/QTBUG-45298 https://bugreports.qt.io/browse/QTCREATORBUG-13697? There are others. Thanks for sticking this out so we can figure out a way to stop it form happening and improve Sigil.