Shader error in Builder

[rolandhill]

Hi Robert,

Running examples that call Builder functions results in shader error messages. I'm using the latest VSG libraries pulled today on Kubuntu 24.04 with Nvidia 3070Ti.

VUID-VkShaderModuleCreateInfo-pCode-08737(ERROR / SPEC): msgNum: -1520283006 - Validation Error: [ VUID-VkShaderModuleCreateInfo-pCode-08737 ] | MessageID = 0xa5625282 | vkCreateShaderModule(): pCreateInfo->pCode (spirv-val produced an error):
Expected Image to have the same type as Result Type Image
%184 = OpSampledImage %183 %177 %181
. The Vulkan spec states: If pCode is a pointer to SPIR-V code, pCode must adhere to the validation rules described by the Validation Rules within a Module section of the SPIR-V Environment appendix (https://vulkan.lunarg.com/doc/view/1.3.290.0/linux/1.3-extensions/vkspec.html#VUID-VkShaderModuleCreateInfo-pCode-08737)
Objects: 0
VUID-VkPipelineShaderStageCreateInfo-pSpecializationInfo-06849(ERROR / SPEC): msgNum: 1132206547 - Validation Error: [ VUID-VkPipelineShaderStageCreateInfo-pSpecializationInfo-06849 ] | MessageID = 0x437c19d3 | vkCreateGraphicsPipelines(): pCreateInfos[0].pStages[1] After specialization was applied, VkShaderModule 0x95a125000000001a[] produces a spirv-val error (stage VK_SHADER_STAGE_FRAGMENT_BIT):
Expected Image to have the same type as Result Type Image
%184 = OpSampledImage %183 %177 %181
. The Vulkan spec states: If a shader module identifier is not specified, the shader code used by the pipeline must be valid as described by the Khronos SPIR-V Specification after applying the specializations provided in pSpecializationInfo, if any, and then converting all specialization constants into fixed constants (https://vulkan.lunarg.com/doc/view/1.3.290.0/linux/1.3-extensions/vkspec.html#VUID-VkPipelineShaderStageCreateInfo-pSpecializationInfo-06849)
Objects: 0
Average frame rate = 116.443

The easiest way to replicate is to run:
vsgbuilder --debug
vsgaxes data/models/teapot.vsgt --debug

As a verification, this runs perfectly with no errors:
vsgviewer data/models/teapot.vsgt --debug

Regards,
Roland

[robertosfield]

I am across this when I upgraded to Kubuntu 24.04 but never found any issues on the VSG setup side, the SPRIR-V code is generated entirely by glslang so the issue likely it stems from there.

Which version of glslang are you building the VSG against?

[rolandhill]

Glslang Version: 11:14.3.0 ESSL Version: OpenGL ES GLSL 3.20 glslang Khronos. 14.3.0 GLSL Version: 4.60 glslang Khronos. 14.3.0 SPIR-V Version 0x00010600, Revision 1 GLSL.std.450 Version 100, Revision 1 Khronos Tool ID 8 SPIR-V Generator Version 11 GL_KHR_vulkan_glsl version 100 ARB_GL_gl_spirv version 100 This is from vulkan SDK 1.3.290.0

…

On Wed, 8 Jan 2025 at 18:13, Robert Osfield ***@***.***> wrote: I am across this when I upgraded to Kubuntu 24.04 but never found any issues on the VSG setup side, the SPRIR-V code is generated entirely by glslang so the issue likely it stems from there. Which version of glslang are you building the VSG against? — Reply to this email directly, view it on GitHub <#1358 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AAPOEQ2GMTWQGL7TZJRG7F32JTFX3AVCNFSM6AAAAABUZGFWEWVHI2DSMVQWIX3LMV43OSLTON2WKQ3PNVWWK3TUHMZDKNZWHEYDGNBTG4> . You are receiving this because you authored the thread.Message ID: ***@***.***>

-- Roland Hill Director Four Winds Technology Pty Ltd Spatial Integration <https://www.spatialintegration.com/>

[robertosfield]

I see the same error when I run vsgbuilder --debug, I don't really know the cause so don't know where to start with trying to resolve it. Nothing has changed with the VSG, it's just recent updates to glslang/drivers appear to resulted in the warning.

Here's my Kubuntu 24.04's glslang details:

$ glslang --version
Glslang Version: 11:15.0.0
ESSL Version: OpenGL ES GLSL 3.20 glslang Khronos. 15.0.0
GLSL Version: 4.60 glslang Khronos. 15.0.0
SPIR-V Version 0x00010600, Revision 1
GLSL.std.450 Version 100, Revision 1
Khronos Tool ID 8
SPIR-V Generator Version 11
GL_KHR_vulkan_glsl version 100
ARB_GL_gl_spirv version 100

[AnyOldName3]

I was running into this yesterday, but thought it was down to the shader optimiser work I was doing. The root cause is basically that the SPIRV-Tools team realised they'd been not forcing the depth parameter of images and samplers to match, so added a check to do that, then it turned out that glslang had been generating shaders with that problem for years, so they rolled the check back and I think they also amended the SPIR-V specification so it was no longer a requirement that it matched.

KhronosGroup/SPIRV-Tools#5781 was the bug report, and KhronosGroup/SPIRV-Tools#5789 was the fix.

Your graphics drivers or Vulkan SDK's validation layer must be using the broken version of SPIRV-Tools. My understanding is that there's nothing that can be changed in the shader to make glslang emit something that will pass validation with the overly-strict version.

[rolandhill]

Today I updated to Vulkan SDK 1.3.296.0 and rebuilt everything. The error messages have gone away! The odd thing is that I now appear to be using exactly the same version as you.

$glslang --version

Glslang Version: 11:15.0.0
ESSL Version: OpenGL ES GLSL 3.20 glslang Khronos. 15.0.0
GLSL Version: 4.60 glslang Khronos. 15.0.0
SPIR-V Version 0x00010600, Revision 1
GLSL.std.450 Version 100, Revision 1
Khronos Tool ID 8
SPIR-V Generator Version 11
GL_KHR_vulkan_glsl version 100
ARB_GL_gl_spirv version 100

[AnyOldName3]

As I said, glslang isn't the problem, it's the validation layer being overly strict due to a SPIRV-Tools bug.

[rolandhill]

Thanks, Chris. I'll close this as it doesn't look like any action is required from the VSG side.