Slang successfully compiles to invalid shaders when duplicate or overlapping system value names are used

[fairywreath]

Slang successfully compiles shader with duplicate built-in decorations, for example:

float4 main(uint vertexID : SV_VertexID, uint anotherVertexID : SV_VertexID) : SV_Position {
    return float4(vertexID * 0.1, 0, 0, 1);
}

This compiles successfully to invalid shaders such as:

struct vertexOutput_0
{
    @builtin(position) output_0 : vec4<f32>,
};

@vertex
fn main(@builtin(vertex_index) vertexID_0 : u32, @builtin(vertex_index) anotherVertexID_0 : u32) -> vertexOutput_0
{
    var _S1 : vertexOutput_0 = vertexOutput_0( vec4<f32>(f32(vertexID_0) * 0.10000000149011612f, 0.0f, 0.0f, 1.0f) );
    return _S1;
}

Built-in/system values cannot be duplicated in the entry point parameter list for HLSL, WGSL and Metal. Slang either needs to error out or transform the duplicated system values to a single param.

[fairywreath]

I cannot assign myself this issue but I will be working on it.