wgpu::Device::create_shader_module() panics on trivial SPIRV input

[curldivergence]

Hi! Not sure if I should create this issue here or in naga repo, please let me know if I should recreate it there. Anyway, when I compile a trivial GLSL shader

#version 330

void main()
{
}

to spirv using glslangValidator, creating a shader module panics with the following callstack:

thread 'main' panicked at 'called `Result::unwrap()` on an `Err` value: UnsupportedBuiltIn(5)', C:\Users\andrew\.cargo\registry\src\github.com-1ecc6299db9ec823\wgpu-0.12.0\src\backend\direct.rs:1022:45
stack backtrace:
   0: std::panicking::begin_panic_handler
             at /rustc/7737e0b5c4103216d6fd8cf941b7ab9bdbaace7c\/library\std\src\panicking.rs:584
   1: core::panicking::panic_fmt
             at /rustc/7737e0b5c4103216d6fd8cf941b7ab9bdbaace7c\/library\core\src\panicking.rs:143
   2: core::result::unwrap_failed
             at /rustc/7737e0b5c4103216d6fd8cf941b7ab9bdbaace7c\/library\core\src\result.rs:1749
   3: enum$<core::result::Result<naga::Module,enum$<naga::front::spv::error::Error> > >::unwrap<naga::Module,enum$<naga::front::spv::error::Error> >
             at /rustc/7737e0b5c4103216d6fd8cf941b7ab9bdbaace7c\library\core\src\result.rs:1065
   4: wgpu::backend::direct::impl$3::device_create_shader_module
             at C:\Users\andrew\.cargo\registry\src\github.com-1ecc6299db9ec823\wgpu-0.12.0\src\backend\direct.rs:1022
   5: wgpu::Device::create_shader_module
             at C:\Users\andrew\.cargo\registry\src\github.com-1ecc6299db9ec823\wgpu-0.12.0\src\lib.rs:1705
   6: brdf_playground::BrdfPlayground::init
             at .\src\main.rs:231
   7: brdf_playground::main
             at .\src\main.rs:421
   8: core::ops::function::FnOnce::call_once<void (*)(),tuple$<> >
             at /rustc/7737e0b5c4103216d6fd8cf941b7ab9bdbaace7c\library\core\src\ops\function.rs:227

Here is human-readable SPIRV dump (via -H command arg):

// Module Version 10000
// Generated by (magic number): 8000a
// Id's are bound by 6

                              Capability Shader
               1:             ExtInstImport  "GLSL.std.450"
                              MemoryModel Logical GLSL450
                              EntryPoint Vertex 4  "main"
                              Source GLSL 330
                              Name 4  "main"
               2:             TypeVoid
               3:             TypeFunction 2
         4(main):           2 Function None 3
               5:             Label
                              Return
                              FunctionEnd

Output of glslangValidator.exe -v is

Glslang Version: 10:11.8.0
ESSL Version: OpenGL ES GLSL 3.20 glslang Khronos. 11.8.0
GLSL Version: 4.60 glslang Khronos. 11.8.0
SPIR-V Version 0x00010600, Revision 1
GLSL.std.450 Version 100, Revision 1
Khronos Tool ID 8
SPIR-V Generator Version 10
GL_KHR_vulkan_glsl version 100
ARB_GL_gl_spirv version 100

Repro steps

1. Write a trivial GLSL shader
2. Compile it using glslangValidator.exe, full command line is

glslangValidator.exe -S vert test.glsl -o  test.vert.spv -G -e "main"

3. Try to create a shader module from it using

let vs_shader = device.create_shader_module(&include_spirv!("../shaders/test.vert.spv"));

4. Observe the mentioned panic.

Expected vs observed behavior I'm not sure I'd expect such a shader to produce a shader module without any errors (initially I wrote a simple, but non-empty shader and reduced the repro case to the trivial one), but

• I'd expect that something that is required would be missing, but the error tells about something being unsupported (which is surprising in such a trivial example)
• I'd expect an error to be more descriptive since currently I have no clue what exactly is not supported

Platform OS: Windows 11 wgpu version: 0.12

Thanks!

[cwfitzgerald]

I believe the issue is the version of GLSL you're using, try 440 -> 460 and it should work. We could definitely improve the error on this one.