example-22-windows crashes creating a new window

[baldurk]

On windows, nvidia, with profile set to 4.3 in config. When I hit c to create a new window it crashes:

Output:

..\..\..\src\renderer_gl.cpp(788): BGFX src API, type Error, id 1282, severity High, 'GL_INVALID_OPERATION error generated. Invalid VAO bound.'
..\..\..\src\renderer_gl.cpp(2907): BGFX CHECK glVertexAttribDivisor(loc, 0); GL error 0x502: GL_INVALID_OPERATION

Callstack:

>   example-22-windowsDebug.exe!bgfx::CallbackStub::fatal(bgfx::Fatal::Enum _code, const char * _str)  Line 83  C++
    example-22-windowsDebug.exe!bgfx::fatal(bgfx::Fatal::Enum _code, const char * _format, ...)  Line 264 + 0x20 bytes  C++
    example-22-windowsDebug.exe!bgfx::ProgramGL::bindAttributes(const bgfx::VertexDecl & _vertexDecl, unsigned int _baseVertex)  Line 2907 + 0x74 bytes C++
    example-22-windowsDebug.exe!bgfx::RendererContextGL::submit(bgfx::Frame * _render, bgfx::ClearQuad & _clearQuad, bgfx::TextVideoMemBlitter & _textVideoMemBlitter)  Line 5020   C++
    example-22-windowsDebug.exe!bgfx::Context::renderFrame()  Line 1177 + 0x3d bytes    C++
    example-22-windowsDebug.exe!bgfx::Context::renderThread(void * _userData)  Line 1840 + 0x8 bytes    C++
    example-22-windowsDebug.exe!bx::Thread::threadFunc(void * _arg)  Line 153 + 0x2b bytes  C++

[JoshuaBrookover]

The crash is related to the default VAO going away in 3.2+. ProgramGL::bindAttributes is being called with an unbound (0) VAO in the case of multiple windows which causes glVertexAttribDivisor to throw GL_INVALID_OPERATION. Fixing the one crash leads to more, and after several hours I haven't managed to find an easy fix.

Since OpenGL 3.2 using Vertex Array Objects is mandatory.

https://www.khronos.org/opengl/wiki/Legacy_OpenGL#Removed_functionality

Additionally, we've been having a lot of trouble with clearQuad() crashing on glDrawArrays with multiple windows and multi-render targets. Our current fix is to "|| true" the "if (1 == numMrt)" to fall into the regular glClear which, for our case, works fine.

edit: also we're falling back to 3.1 for now to avoid the default VAO deprecated problem

[JoshuaBrookover]

Managed to get something working. I'm not sure it's an ideal fix, but hopefully it'll help @bkaradzic fix this one.

https://github.com/JoshuaBrookover/bgfx/commit/b04ec484b44c241b6282d778098820e39204c01d

[alemuntoni]

The 22-windows example still crashes with OpenGL backend when pressing c (the first window appears as expected), and this happens both on Windows and Linux.

Windows log:

[...]
bgfx\src\renderer_gl.cpp (1259): BGFX src API, type Error, id 1282, severity High, 'GL_INVALID_OPERATION error generated. Invalid VAO bound.'
bgfx\src\renderer_gl.cpp(5422): ASSERT 0 == gl_err -> glVertexAttribDivisor(loc, 0); GL error 0x502: GL_INVALID_OPERATION
bgfx\src\renderer_gl.cpp (5422): BGFX FATAL 0x00000000: glVertexAttribDivisor(loc, 0); GL error 0x502: GL_INVALID_OPERATION

Linux log:

[...]
/bgfx/src/renderer_gl.cpp(5438): ASSERT 0 == gl_err -> glVertexAttribPointer(loc , num , s_attribType[type] , normalized , _layout.m_stride , (void*)(uintptr_t)baseVertex); GL error 0x502: GL_INVALID_OPERATION
/bgfx/src/renderer_gl.cpp (5438): BGFX FATAL 0x00000000: glVertexAttribPointer(loc , num , s_attribType[type] , normalized , _layout.m_stride , (void*)(uintptr_t)baseVertex); GL error 0x502: GL_INVALID_OPERATION

Does anyone have a clue on how to fix this?

[bkaradzic]

I tried to reproduce locally on Linux but I'm unable, it just works as expected. Try updating your drivers first. If that doesn't work I need more info about your setup.

[alemuntoni]

I am running the 545 nvidia drivers, which are the latest one available on Ubuntu 22.04...
btw, I tried both wayland and x.org, same result.

This is the output of nvidia-smi:

Thu Feb  1 16:52:24 2024       
+---------------------------------------------------------------------------------------+
| NVIDIA-SMI 545.29.06              Driver Version: 545.29.06    CUDA Version: 12.3     |
|-----------------------------------------+----------------------+----------------------+
| GPU  Name                 Persistence-M | Bus-Id        Disp.A | Volatile Uncorr. ECC |
| Fan  Temp   Perf          Pwr:Usage/Cap |         Memory-Usage | GPU-Util  Compute M. |
|                                         |                      |               MIG M. |
|=========================================+======================+======================|
|   0  NVIDIA GeForce GTX 1080        Off | 00000000:27:00.0  On |                  N/A |
|  0%   53C    P0              61W / 180W |    502MiB /  8192MiB |      0%      Default |
|                                         |                      |                  N/A |
+-----------------------------------------+----------------------+----------------------+
                                                                                         
+---------------------------------------------------------------------------------------+
| Processes:                                                                            |
|  GPU   GI   CI        PID   Type   Process name                            GPU Memory |
|        ID   ID                                                             Usage      |
|=======================================================================================|
|    0   N/A  N/A      1500      G   /usr/lib/xorg/Xorg                          339MiB |
|    0   N/A  N/A      1670      G   /usr/bin/gnome-shell                        155MiB |
|    0   N/A  N/A      4622      G   /usr/lib/insync/insync                        2MiB |
|    0   N/A  N/A     14336      G   /opt/Qt/Tools/QtCreator/bin/qtcreator         2MiB |
+---------------------------------------------------------------------------------------+

Let me know if you need some other info!