[SPIR-V] `vk::SpirvOpaqueType` as a descriptor , always gets placed in `$Globals`

Description

Suppose

Steps to Reproduce

My custom Godbolt

#include "nbl/builtin/hlsl/spirv_intrinsics/core.hlsl"

namespace nbl
{
namespace hlsl
{
namespace spirv
{
//[[vk::ext_capability(spv::CapabilityRayQueryKHR)]]
using RayQueryKHR = vk::SpirvOpaqueType<spv::OpTypeRayQueryKHR>;

//[[vk::ext_capability(spv::CapabilityRayQueryKHR)]]
using AccelerationStructureKHR = vk::SpirvOpaqueType<spv::OpTypeAccelerationStructureKHR>;

//using RayQueryEXT = pointer_t<>;


[[vk::ext_capability(spv::CapabilityRayQueryKHR)]]
[[vk::ext_instruction(spv::OpRayQueryInitializeKHR)]]
void rayQueryInitializeKHR([[vk::ext_reference]] RayQueryKHR query, [[vk::ext_reference]] AccelerationStructureKHR AS, uint32_t flags, uint32_t cull_mask, float32_t3 origin, float32_t tmin, float32_t3 direction, float32_t tmax);
}
}
}


using namespace nbl::hlsl;

[[vk::binding(0,0)]] spirv::AccelerationStructureKHR topLevelAS;

[numthreads(64,1,1)]
void main()
{
    spirv::RayQueryKHR rq;
    spirv::rayQueryInitializeKHR(rq,topLevelAS,0x0,0x0,float32_t3(1.f,2.f,3.f),0.125f,float32_t3(0.f,0.f,1.f),2048.f);
}

The funny thing is that if I replace with

[[vk::binding(0,0)]] static spirv::AccelerationStructureKHR topLevelAS;

if compiles and codegens completely wrong SPIR-V, (the variable is not in Uniform class, doesn't have the binding decorations, etc.

Actual Behavior

<source>:28:3: error: variable 'topLevelAS' will be placed in $Globals so cannot have vk::binding attribute
[[vk::binding(0,0)]] spirv::AccelerationStructureKHR topLevelAS;
  ^

Compiler returned: 3221225477

Environment

• DXC version: trunk from Novemeber
• Host Operating System: Windows

Start by running the linked Godbolt reproduction and compare the ordinary and static declarations of topLevelAS. Done means the non-static vk::binding declaration no longer reports placement in $Globals, while the generated SPIR-V preserves the Uniform class, binding decorations, and related descriptor behavior.