Error while specializing generic functions with more than 1 type

[il1aster]

Hi,

Attempting to use generic functions with more than 1 type causes errors when compiling a slang module with runtime specialization of the component types. I reproduced this with the shader-toy sample by adding unused type parameters to the generic fragment shader function:

[shader("fragment")]
float4 fragmentMain<T : IShaderToyImageShader, U : IShaderToyImageShader, V: IShaderToyImageShader>(
    float4 sv_position : SV_Position)
    : SV_Target

and duplicating the specialization in the argument list passed to specialize():

    Slang::List<slang::SpecializationArg> specializationArgs;
    {
        slang::SpecializationArg effectTypeArg;
        effectTypeArg.kind = slang::SpecializationArg::Kind::Type;
        effectTypeArg.type = effectType;
        specializationArgs.add(effectTypeArg);
        specializationArgs.add(effectTypeArg);
        specializationArgs.add(effectTypeArg);
    }

The above modifications compile and run in debug mode with v2023.1.1 (similar to #3759), but produces the following error in master.

[GraphicsLayer]: INFO: CreateDevice: Debug layer is enabled.
shader-toy.slang(109): error 38005: expected a type as argument for specialization parameter '4'
float4 fragmentMain<T : IShaderToyImageShader, U : IShaderToyImageShader, V: IShaderToyImageShader>(

Thanks