In Slang 2025.13.2, with this code:

public interface IBase
{
    public void step(inout float f);
}

public struct Impl : IBase
{
    public void step(inout float f)
    {
        f += 1.0f;
    }
}

When I load the module, ask for the layout, get findTypeByName("Impl") and then findFunctionByNameInType on step, I get a slang::FunctionReflection that returns NULL for getName()