Multi-viewport memory leak with GLFW/OpenGL3 on W10

[altaitai]

Version/Branch of Dear ImGui:

Version: 1.89.2 WIP (18916)
Branch: docking

Back-end/Renderer/Compiler/OS

Back-ends: imgui_impl_glfw.cpp + imgui_impl_opengl3.cpp
Compiler: VS2019 SDK 10.0 (v142)
Operating System: Windows 10

My Issue/Question:

I noticed a memory leak on the stack when running the multi-viewport branch in my project. It's currently reproducible in the example_glfw_opengl3 project in the official VS solution. The leak happens in ImGui_ImplOpenGL3_RenderDrawData and ImGui::RenderPlatformWindowsDefault specifically when we move a window outside of the main viewport. When the window is moved in, the leak stops and the memory usage comes back to the idle state.

Screenshots/Video

Standalone, minimal, complete and verifiable example:

GLFW/OpenGL3 Example

[ocornut]

We've circled around this forever and it seems to be a bug in Intel GPU drivers that apparently was fixed last year?

• Please confirm/provide GPU and Driver Version + after please try to update drivers?

• Reference: see b8b0f9d (issues Memory leak with with viewports when using OpenGL3 backend #4468, multi-viewport memory leaks #4504, Memory leak on resize of secondary viewport #3381, Possible memory leak. opengl3 #2981, Access violation on the line of glBufferSubData() #4825, Multi-viewports rendering artifacts with OpenGL backend on 1.86 #4832, Windows Blinking On OpenGL3 Problem #5127)

• Try to change bd->UseBufferSubData = false; to = true in imgui_impl_opengl3.cpp.

[altaitai]

We've circled around this forever and it seems to be a bug in Intel GPU drivers that apparently was fixed last year?

• Please confirm/provide GPU and Driver Version + after please try to update drivers?
• Reference: see b8b0f9d (issues Memory leak with with viewports when using OpenGL3 backend #4468, multi-viewport memory leaks #4504, Memory leak on resize of secondary viewport #3381, Possible memory leak. opengl3 #2981, Access violation on the line of glBufferSubData() #4825, Multi-viewports rendering artifacts with OpenGL backend on 1.86 #4832, Windows Blinking On OpenGL3 Problem #5127)

Thanks for the quick reply, this is most likely the issue. Drivers on the test machine are outdated (January 2021) and I cannot update them, but fortunately I was able to re-test on another GPU which worked fine. Closing as a duplicate of the mentioned issue.