Hang when destroying viewports in example_sdl2_opengl3 (only when vsync is deactivated) about imgui HOT 4 OPEN

It looks like it's actually stuck within SDL_GL_DeleteContext. I imagine if you enabled showing external code in the stack trace that you'd see it's stuck in your graphics driver. You should try updating it. It'd also be helpful to know what GPU you have

from imgui.

You are right!

So, I have a Radeon RX 5500M and an Integrated AMD Ryzen 7 4800H with Radeon graphics (I assume that means it's just an integrated card. Sad to say I don't know much about Graphic card numbers or types. Also, aren't both cards integrated when they are inside a laptop?). The drivers are up to date.

Just for curiosity's sake, I tried to force the example to use the dedicated card. This seems to take care of the issue for some reason. Although the problem persists on the integrated graphics card.
extern "C" { __declspec(dllexport) int AmdPowerXpressRequestHighPerformance = 1; }

from imgui.

I use neither SDL nor OpenGL, but this sounds a lot like the backend trying to release resources that are still in use by the graphics hardware. Basically a synchronization issue, which means that the crash depends on timing and GPU load. In that case it should happen even with VSync enabled if you saturate your GPU with work and it didn't have enough time to catch up yet when destroying the context. Depending on the guarantees OpenGL makes this could be an error in the backend implementation (improper synchronization) or a driver bug.

from imgui.

I assume that means it's just an integrated card.

Correct. The Ryzen GPU is your iGPU and the Radeon one is your dGPU.

Also, aren't both cards integrated when they are inside a laptop?

In modern times "integrated GPUs" refers to GPUs integrated with the CPU. (As opposed to GPUs integrated into the motherboard like you used to see on desktops eons ago.)

The drivers are up to date.

That is unfortunate because this smells like a driver bug.

Could you see if the issue happens with example_glfw_opengl3? I imagine it does, but in the off chance it doesn't that might mean a workaround exists for us.

Just for curiosity's sake, I tried to force the example to use the dedicated card. This seems to take care of the issue for some reason. Although the problem persists on the integrated graphics card.

Good test!

Yeah, the issue applying specifically to the iGPU probably part of the bug from AMD's perspective.

this sounds a lot like the backend trying to release resources that are still in use by the graphics hardware.

@GamingMinds-DanielC Good theory, but in OpenGL object lifetimes are managed by the driver so even if this is the case it's still a driver bug.

from imgui.