[clang] [C++20][Modules] Load function body from the module that gives canonical decl (PR #111992)

[Haojian Wu via cfe-commits]

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@@ -798,6 +798,17 @@ void ASTDeclWriter::VisitFunctionDecl(FunctionDecl *D) {
     }
   }
 
+  if (D->getFriendObjectKind()) {
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hokein wrote:

As stated in https://github.com/llvm/llvm-project/issues/122493#issuecomment-2602473058, this is intended. It would be helpful to include comments explaining why this logic is applied exclusively to friend objects.



https://github.com/llvm/llvm-project/pull/111992