Crash when using Edit mode during playback of a song containing a Sampletrack

[Sauerstoffdioxid]

When using the edit mode to move large parts of a song containing a Sampletrack, the square indicating what area is being selected seems quite frail. Eventually, after moving the selected parts a couple of seconds, LMMS may crash.

The selection:

And, after about 20 seconds of moving it around, the crash:

After that, LMMS closes. (Interestingly, apart from the stuttering audio, it's still fully responsive as long as the box is shown.)

I read somewhere there were issues with large Sampletracks of 100MB+. However, the sample I had loaded was an ~7MB FLAC, so this shouldn't be related.

Win10 64bit, LMMS-rc5 x64

[tresf]

@Sauerstoffdioxid thanks. Yeah, there's a lot going on there that could trigger a crash, you have multiple events happening at once.

The fact that the audio keeps playing is suggestive that it's a bug in the UI, but we'll see if we can reproduce on a platform with a full backtrace and escalate as needed.

Note, for you or anyone interested in helping squash bugs like this, we have a stellar tutorial for building and debugging on Linux and Mac. Linux runs great inside VirtualBox atop Windows and we can help you get it all setup in #support on Discord. I say this because we're 100% volunteer based and we need all of the help we can get, even if it's just reproducing and providing a backtrace. :)

[Sauerstoffdioxid]

I won't be able to install Linux anytime soon but I can test the bug a bit more on Windows.

Firstly, I wanted to clearify the statement about the sound still playing: it's a short (~1 second) loop which is kinda what I'd expect from a music programme crashing. However, as long as the text box isn't closed, the UI of LMMS is still responsive, i. e. I can still drag around/move note patterns.

Secondly, after some more testing, it turns out this are actually two different bugs which aren't related much to each other:

• First, there's the bug of the resizing square becoming very frail. The effect is much worse when I load the WAVE version instead of the FLAC (tested on the default project). If I disable the Sample Track, the selection works perfectly.

• ... and second, there's the crash. I recreated it with just a bunch of empty BB tracks (in this case 6 B+B lines with 32 patterns each). The less patterns are moved, the longer it will take for the crash to happen.

[PhysSong]

Reproduced. It looks like #3956 though I'm not sure. I'll post a test build with a potential fix in a couple of days.

[PhysSong]

@Sauerstoffdioxid Can you still reproduce this issue? If so, could you test this version?
https://github.com/PhysSong/lmms/releases/download/vdummy/lmms-1.2.0-rc5.61-win64.exe

[Sauerstoffdioxid]

@PhysSong Seems to be fixed. 👍

[PhysSong]

Then I'll open a pull request soon.