Cannot find EModeSlider referenced in crash stack trace


Does anybody have a clue where or what an EModeSlider might be?

I’m trying to track down a crash and the one and only stack trace I have references an EModeSlider (or possibly just ModeSlider) which I cannot find anywhere in my source, the Rack SDK or any of the other Rack source code (including glfw and nanosvg):

27: ZN4rack3app9SvgSwitch8addFrameESt10shared_ptrINS_6window3SvgEE 0x7feec59a110 
26: ZN11EModeSliderC1Ev 0x7fef62e3516 
25: ZN12SN_VCOWidgetC1EP6SN_VCO 0x7fef62f5890 
24: ZZN4rack11createModelI6SN_VCO12SN_VCOWidgetEEPNS_6plugin5ModelENSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEEEN6TModel18create

Is your code on GitHub for us to look at? Context is everything.

Oh, this is a continuation of Right-click death - #16 by transcriptaze

It would make it much easier to help you if you tie these things together, and provide links to provide the full context, such as:

the full stack trace in the github issue: sn-vcv/res/sn-vco.svg at issue#2 · transcriptaze/sn-vcv (

The stack trace is bizarre, because your module doesn’t have an SvgSwitch, but the crashing code is creating one.

There’s a half a chance this isn’t your module at all and that something else is corrupting memory.

It would interesting to get a list of all the modules that are installed. “sn” doesn’t strike me as a very unique plugin slug, and I wonder if there’s some weird collision happening.

Here’s one hit, note the inheritance.

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I peeked at the sn code. It guards for module null.

I had two comments. In the sm vco channel init yur module to null for good measure and your step should call the parent step

But this stack looks like something clobbered you before you started. Nothing you do constructs an eslider in the code I agree

Yes, it’s unfortunately common for one bad module to corrupt memory such that some other inccocent module crashes.

It seems the 8Mode softSN module has a precedent for crashing the browser on right-click

Here’s what I suspect has happened: the user has added an sn-vco to a blank patch, has then right-clicked to bring up the browser - if they have the modules sorted by Brand then 8Mode is going to be on the first page of the modules that appear. This would create a EModeSlider from a SliderSwitch from a SvgSwitch which is where the crash occurs.

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@Steve_Russell. Oh … that makes total sense! Thanks! I’ve been going through my code with a tooth comb looking for a place where it would cause a crash like that and coming up completely blank.

@baconpaul. Thanks - will fix those. Normally do initialise everything, that one somehow slipped through :-(.

Thanks for the help guys - was tearing my hair out!

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