[clang] Reland [C++20] [Modules] [Itanium ABI] Generate the vtable in the mod… (PR #102287)

[Chuanqi Xu via cfe-commits]

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@@ -1081,29 +1081,41 @@ llvm::GlobalVariable::LinkageTypes
 CodeGenModule::getVTableLinkage(const CXXRecordDecl *RD) {
   if (!RD->isExternallyVisible())
     return llvm::GlobalVariable::InternalLinkage;
-
-  // We're at the end of the translation unit, so the current key
-  // function is fully correct.
-  const CXXMethodDecl *keyFunction = Context.getCurrentKeyFunction(RD);
-  if (keyFunction && !RD->hasAttr<DLLImportAttr>()) {
+  
+  // In windows, the linkage of vtable is not related to modules.
+  bool IsInNamedModule = !getTarget().getCXXABI().isMicrosoft() &&
+        RD->isInNamedModule();
+  // If the CXXRecordDecl are not in a module unit, we need to get
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ChuanqiXu9 wrote:

Done

https://github.com/llvm/llvm-project/pull/102287