[clang] [win][clang] Align scalar deleting destructors with MSABI (PR #139566)

[Tom Honermann via cfe-commits]

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@@ -2886,6 +2887,16 @@ class CXXDestructorDecl : public CXXMethodDecl {
     return getCanonicalDecl()->OperatorDelete;
   }
 
+  const FunctionDecl *getOperatorGlobalDelete() const {
+    return getCanonicalDecl()->OperatorGlobalDelete;
+  }
+
+  void setOperatorGlobalDelete(FunctionDecl *OD) {
+    auto *First = cast<CXXDestructorDecl>(getCanonicalDecl());
+    if (OD && !First->OperatorGlobalDelete)
+      First->OperatorGlobalDelete = OD;
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tahonermann wrote:

Good question. Adding a parallel set of functions seems reasonable to me. It might also be reasonable to tie the updates together, but I think that might unnecessarily increase the serialized AST size for Itanium targets. Perhaps that can be avoided in either case; it isn't obvious to me.

While looking at this some more, I noticed that it looks like updates will be needed to `clang/lib/AST/ASTImporter.cpp` as well; see the call to `setOperatorDelete()` in `ASTNodeImporter::VisitFunctionDecl()`.

https://github.com/llvm/llvm-project/pull/139566