Segfault when right-clicking hotcues on waveform overview

[jus]

Mixxx" "2.3.0-beta" "(git 2.3 r7414)

macos 10.14.6

Steps to reproduce:

* Load a track
* Create Hotcue
* Right-click hotcue point on waveform overview

Expected:
* Hotcue menu widget opens

What happens:
* Segfault

Backtrace
https://pastebin.com/BDVzAXWT

Note:
I´m running in safemode, because GUI is terrible lagging in regular mode.

./mixxx --developer --resourcePath res --safemode --loglevel debug

[Foss-4 (foss-4)]

last 2.3.0 master build is:
2.3.0-alpha-pre (build master r7367) on http://downloads.mixxx.org/builds/master/release/

No problems here creating a hotcue and then right-clicking that hotcue on the waveform on macOS 10.15.4.

@Jus: Could you retest with that same build and see how it behaves for you?

[jus (jus)]

Thanks for testing.
2.3.0-alpha-pre (build master r7367) is ok for me too, but 2 weeks old

Could you try the newer
http://downloads.mixxx.org/builds/2.3/release/mixxx-2.3.0-beta-2.3-git7414-release-macintel64.dmg

I can reproduce the segfault with this version when starting Mixxx using safemode

/Applications/Mixxx.app/Contents/MacOS/Mixxx --safemode

[Be (be.ing)]

I cannot reproduce this on Fedora 32. Maybe it only happens on macOS?

From the backtrace, the crashing code is:
const auto screenSize = widget.windowHandle()->screen()->size();

It seems QWidget::windowHandle is returning a null pointer so the call to QWindow::screen is crashing. I do not know why QWidgett::windowHandle would return a null pointer. Does it make a difference whether Mixxx is full screen or not?

[Foss-4 (foss-4)]

Sorry I missed this as I am not closely following launchpad.
Retested 2.3.0-beta (build 2.3 r7419)

Normal mode: ok

Safe mode: confirming the crash: set the cue point on the overview-waveform and right clicking it, crashes mix:
https://bin.disroot.org/?ac56580a25237927#EvdQ46SdyuUUQT35nJuA6Y31uZDEMgk9d7CYFMAeSkP

Important sidenode for safe mode: no waveforms are loading and controller not recognized. not sure if that is expected.

tried both fullscreen and window mode: both crash when right clicking hotcue.

This is the terminal output while running in safe mode:

```
/Applications/Mixxx.app/Contents/MacOS/Mixxx --safemode
Warning [Main]: Configuration file is at version "2.1.1-pre" instead of the current 2.3.0-beta
Warning [Main]: ControlDoublePrivate::getControl returning NULL for ( "[AutoDJ]" , "enabled" )
Warning [Main]: Cannot open file 'skin:/buttons_classic/btn__.svg', because: No such file or directory
Warning [Main]: Cannot open file 'skin:/buttons_classic/btn___pressed.svg', because: No such file or directory
Warning [Main]: Cannot open file 'skin:/buttons_classic/btn___active.svg', because: No such file or directory
Warning [Main]: WaveformRenderMark::setup - redefinition of "cue_point"
Warning [Main]: WaveformRenderMark::setup - redefinition of "cue_point"
Warning [Main]: WaveformRenderMark::setup - redefinition of "cue_point"
Warning [Main]: WaveformRenderMark::setup - redefinition of "cue_point"
Warning [Main]: Cannot open file 'skin:/buttons_classic/btn_elevated_.svg', because: No such file or directory
Warning [Main]: Cannot open file 'skin:/buttons_classic/btn_elevated__active.svg', because: No such file or directory
Warning [Main]: WWidgetGroup(0x7f836861b920, name="MicAuxPlayBox") does not have a property named "alignment"
Warning [Main]: WWidgetGroup(0x7f83687213a0, name="MicAuxPlayBox") does not have a property named "alignment"
Warning [Main]: WWidgetGroup(0x7f836864b770, name="MicAuxPlayBox") does not have a property named "alignment"
Warning [Main]: WWidgetGroup(0x7f8367e36e30, name="MicAuxPlayBox") does not have a property named "alignment"
Warning [Main]: WWidgetGroup(0x7f83686a12f0, name="MicAuxPlayBox") does not have a property named "alignment"
Warning [Main]: WWidgetGroup(0x7f836874a900, name="MicAuxPlayBox") does not have a property named "alignment"
Warning [Main]: WWidgetGroup(0x7f83686e5b40, name="MicAuxPlayBox") does not have a property named "alignment"
Warning [Main]: WWidgetGroup(0x7f83685646e0, name="MicAuxPlayBox") does not have a property named "alignment"
Warning [Main]: WWidgetGroup(0x7f8368629190, name="MicAuxAddBox") does not have a property named "alignment"
Warning [Main]: WWidgetGroup(0x7f8368727670, name="MicAuxAddBox") does not have a property named "alignment"
Warning [Main]: WWidgetGroup(0x7f8368651a00, name="MicAuxAddBox") does not have a property named "alignment"
Warning [Main]: WWidgetGroup(0x7f8368658c10, name="MicAuxAddBox") does not have a property named "alignment"
Warning [Main]: WWidgetGroup(0x7f83686c2510, name="MicAuxAddBox") does not have a property named "alignment"
Warning [Main]: WWidgetGroup(0x7f8368755d10, name="MicAuxAddBox") does not have a ...

[Be (be.ing)]

Hack around the crash, but this doesn't solve the underlying problem:
https://github.com/mixxxdj/mixxx/pull/2860

[Swiftb0y (swiftb0y)]

Mixxx now uses GitHub for bug tracking. This bug has been migrated to:
https://github.com/mixxxdj/mixxx/issues/9990