[llvm-branch-commits] [clang] [HLSL] Constant buffers codegen (PR #124886)

[Justin Bogner via llvm-branch-commits]

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@@ -5743,6 +5747,17 @@ HLSLBufferDecl *HLSLBufferDecl::CreateDeserialized(ASTContext &C,
                                     SourceLocation(), SourceLocation());
 }
 
+const CXXRecordDecl *HLSLBufferDecl::getLayoutStruct() const {
+  // Layout struct is the last decl in the HLSLBufferDecl.
+  if (CXXRecordDecl *RD = llvm::dyn_cast_or_null<CXXRecordDecl>(LastDecl)) {
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bogner wrote:

This seems incredibly sketchy. Why is `LastDecl` appropriate here? What would it mean if `LastDecl` was removed from the `DeclarationContext` as the comment near it's definition says it may be? Is this just straight up relying on the order that the decls are created and hoping that that means it's the decl we're looking for?

https://github.com/llvm/llvm-project/pull/124886