[clang] [HLSL] Add ByteAddressBuffer definition to HLSLExternalSemaSource #113477 (PR #116699)

[Helena Kotas via cfe-commits]

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@@ -1474,6 +1474,11 @@ DeclContext *DeclContext::getPrimaryContext() {
   case Decl::ObjCCategoryImpl:
     return this;
 
+  case Decl::CXXRecord:
+    if (auto *OPD = dyn_cast<CXXRecordDecl>(this))
+      if (auto *Def = OPD->getDefinition())
+        return Def;
+    return this;
   default:
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hekota wrote:

Why is this necessary?

https://github.com/llvm/llvm-project/pull/116699