error: Flags must match usage.

This shader causes an error.

[numthreads(8, 8, 1)]
void computeRTAO(
	uint3 groupId : SV_GroupID,
	uint3 groupThreadId : SV_GroupThreadID,
	uint3 dispatchThreadId : SV_DispatchThreadID,
	uint groupIndex : SV_GroupIndex )
{
  RayQuery<RAY_FLAG_CULL_NON_OPAQUE |
             RAY_FLAG_SKIP_PROCEDURAL_PRIMITIVES |
             RAY_FLAG_ACCEPT_FIRST_HIT_AND_END_SEARCH |
			 RAY_FLAG_CULL_BACK_FACING_TRIANGLES> rq;
}

error: validation errors
error: Flags must match usage.
note: Flags declared=33554432, actual=0
Validation failed.

Compiler command line:

dxc /nologo /all_resources_bound /Ges /WX /O3 /T cs_6_6 /E computeRTAO /Fo shader.cso shader.hlsl

I tested with June 2021 DXC release.

Reproduce the failure with the provided HLSL shader and the dxc command line using the June 2021 DXC release. Start by tracing validation for RayQuery flags and compare the declared and actual values shown in the diagnostic. Done means the reported shader is validated without the erroneous “Flags must match usage” failure, with regression coverage for this case.