cancel
Showing results for 
Search instead for 
Did you mean: 

OpenGL & Vulkan

Pok
Journeyman III

GLSL linking error: "Fail to build reflection info."

Hello,

Based on https://community.amd.com/t5/opengl-vulkan/doesn-t-work-glpixeltransferf-and-error-in-shader-on-open..., I believe you already have an internal ticket for this issue, but I would like to provide some additional background info and I cannot post in the OpenGL community.

I work on an OpenGL-based renderer for Unreal Engine 1 games, and one of our users is reporting a linking failure for the shaders that render level geometry. The error we retrieve using glGetProgramiv/glGetProgramInfoLog simply says: "Fail to build reflection info.".

The shaders in question pass quite a lot of data from the vertex to the fragment shaders, though, as far as we can tell, not enough to hit any of the implementation-defined limits.

After quite extensive debugging, however, we suspect that the 23.7.2 driver supports fewer varying vectors and/or output components than advertised/required by the GL spec.

I have uploaded two zip files with GLSL code. This set of shaders triggers the linking error. After disabling just one feature, the shaders look like this, and the problem disappears. There are other optional features that, when disabled, remove just one or two output variables (usually vec2 typed) from the vertex shader, which then also fixes the problem.

The user has a Radeon RX 570 card and runs on the latest 64-bit Windows 10 with the 23.7.2.230718 drivers. The game we tested was the 64-bit version of Unreal 1 (227k patch).

Thanks

0 Likes
7 Replies
dipak
Big Boss

Hi @Pok ,

Thanks for reporting it. I have whitelisted you and moved the post to the OpenGL forum.

I will forward the issue to the OpenGL team.

Thanks.

0 Likes
dipak
Big Boss

Hi @Pok ,

I have uploaded two zip files with GLSL code. This set of shaders triggers the linking error. After disabling just one feature, the shaders look like this, and the problem disappears. 

The OpenGL team was unable to download the GLSL code using the above links.  When they clicked "this", nothing happened. Could you please check it and provide new download links?

Thanks.

0 Likes
Pok
Journeyman III

Hi @dipak, both links work fine for me. Is there any way I could just send you the files? The forum won't allow me to attach .zip files, but perhaps I could just mail you the files? Their combined size is only 15Kb.

0 Likes

Hi @Pok 

I tried to send you a private message (PM), however it seems the PM option is not yet enabled for you. I have asked our community admin team to enable the PM and file attachment options for you. Will let you know once they enable those options.

Thanks.

0 Likes

The community admin team has enabled those options for you. Now you should be able to attach the zip files using "Drag and drop here or browse files to attach" option as shown below:

attachment_option.jpg

0 Likes

Hi @Pok ,

Thanks for providing the new download links via PM. I was able to download the .zip files using the new links. I have attached the .zip files here: https://community.amd.com/t5/opengl-vulkan/glsl-linking-error-quot-fail-to-build-reflection-info-quo...

Thanks.

0 Likes

Here is the feedback from the OpenGL team:

"We investigated the shaders provided by the end-user. The separate shader DrawComplex.vert failed to compile, because we don't pack on separate mode.  Please try to compile the the shaders through vs-fs pipeline. 

And the limit for the max vertex output component is 64."

Thanks.

0 Likes