diff --git a/tools/clang/lib/SPIRV/AstTypeProbe.cpp b/tools/clang/lib/SPIRV/AstTypeProbe.cpp
index c933a82c16..a871bd3577 100644
--- a/tools/clang/lib/SPIRV/AstTypeProbe.cpp
+++ b/tools/clang/lib/SPIRV/AstTypeProbe.cpp
@@ -1141,12 +1141,13 @@ bool isOpaqueType(QualType type) {
     if (name == "RaytracingAccelerationStructure")
       return true;
 
-    if (name == "RayQuery")
-      return true;
-
     if (name == "SubpassInput")
       return true;
   }
+
+  if (hlsl::IsHLSLRayQueryType(type))
+    return true;
+
   return false;
 }
 
diff --git a/tools/clang/lib/SPIRV/LowerTypeVisitor.cpp b/tools/clang/lib/SPIRV/LowerTypeVisitor.cpp
index 4c06cd4113..b330d40d85 100644
--- a/tools/clang/lib/SPIRV/LowerTypeVisitor.cpp
+++ b/tools/clang/lib/SPIRV/LowerTypeVisitor.cpp
@@ -965,7 +965,7 @@ LowerTypeVisitor::lowerResourceType(QualType type, SpirvLayoutRule rule,
     return spvContext.getAccelerationStructureTypeNV();
   }
 
-  if (name == "RayQuery")
+  if (hlsl::IsHLSLRayQueryType(type))
     return spvContext.getRayQueryTypeKHR();
 
   if (name == "StructuredBuffer" || name == "RWStructuredBuffer" ||
diff --git a/tools/clang/test/CodeGenSPIRV/type.rayquery.user-defined-shadow.hlsl b/tools/clang/test/CodeGenSPIRV/type.rayquery.user-defined-shadow.hlsl
new file mode 100644
index 0000000000..eddf73a31b
--- /dev/null
+++ b/tools/clang/test/CodeGenSPIRV/type.rayquery.user-defined-shadow.hlsl
@@ -0,0 +1,35 @@
+// RUN: %dxc -T cs_6_6 -E MainRayGenShader -fcgl -spirv %s | FileCheck %s
+
+// A user-defined struct named "RayQuery" that shadows the reserved intrinsic
+// name must be lowered as an ordinary struct, not as the opaque ray query
+// type. Previously this crashed the SPIR-V backend.
+// See https://github.com/microsoft/DirectXShaderCompiler/issues/8601
+
+namespace UnifiedRT {
+struct RayQuery {
+  float4 foo;
+};
+} // namespace UnifiedRT
+
+// The shadowing struct is lowered to an ordinary struct with a float4 field,
+// and the local variable uses that struct type in the Function storage class.
+// CHECK: %RayQuery = OpTypeStruct %v4float
+// CHECK: %_ptr_Function_RayQuery = OpTypePointer Function %RayQuery
+// CHECK: %rayQuery = OpVariable %_ptr_Function_RayQuery Function
+
+// It must not be lowered to the opaque ray query type.
+// CHECK-NOT: OpTypeRayQueryKHR
+
+StructuredBuffer<uint> _UnifiedRT_DispatchDims;
+
+[numthreads(128, 1, 1)]
+void MainRayGenShader(in uint3 gidx : SV_DispatchThreadID,
+                      in uint lidx : SV_GroupIndex) {
+  if (gidx.x >= _UnifiedRT_DispatchDims[0] ||
+      gidx.y >= _UnifiedRT_DispatchDims[1] ||
+      gidx.z >= _UnifiedRT_DispatchDims[2])
+    return;
+
+  UnifiedRT::RayQuery rayQuery;
+  rayQuery.foo = float4(1.0, 1.0, 1.0, 1.0);
+}