[clang] [RFC] Initial implementation of P2719 (PR #113510)

[via cfe-commits]

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@@ -3499,15 +3506,35 @@ bool FunctionDecl::isDestroyingOperatorDelete() const {
   //   Within a class C, a single object deallocation function with signature
   //     (T, std::destroying_delete_t, <more params>)
   //   is a destroying operator delete.
-  if (!isa<CXXMethodDecl>(this) || getOverloadedOperator() != OO_Delete ||
-      getNumParams() < 2)
+  if (!isa<CXXMethodDecl>(this) || getOverloadedOperator() != OO_Delete)
+    return false;
+
+  unsigned DestroyingDeleteTagParam = 1;
+  if (isTypeAwareOperatorNewOrDelete())
+    ++DestroyingDeleteTagParam;
+
+  if (getNumParams() <= DestroyingDeleteTagParam)
     return false;
 
-  auto *RD = getParamDecl(1)->getType()->getAsCXXRecordDecl();
+  auto *RD =
+      getParamDecl(DestroyingDeleteTagParam)->getType()->getAsCXXRecordDecl();
   return RD && RD->isInStdNamespace() && RD->getIdentifier() &&
          RD->getIdentifier()->isStr("destroying_delete_t");
 }
 
+bool FunctionDecl::isTypeAwareOperatorNewOrDelete() const {
+  if (getDeclName().getNameKind() != DeclarationName::CXXOperatorName)
+    return false;
+  if (getDeclName().getCXXOverloadedOperator() != OO_New &&
+      getDeclName().getCXXOverloadedOperator() != OO_Delete &&
+      getDeclName().getCXXOverloadedOperator() != OO_Array_New &&
+      getDeclName().getCXXOverloadedOperator() != OO_Array_Delete)
+    return false;
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cor3ntin wrote:

Maybe we should introduce
```
DeclarationName::isOperatorNew
DeclarationName::isOperatorDelete
DeclarationName::isOperatorNewOrDelete
```

to clean that up

https://github.com/llvm/llvm-project/pull/113510