[clang] [C++20] [Modules] [Itanium ABI] Generate the vtable in the module unit of dynamic classes (PR #75912)

[Eli Friedman via cfe-commits]

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@@ -3219,7 +3219,8 @@ void CodeGenModule::EmitVTablesOpportunistically() {
   for (const CXXRecordDecl *RD : OpportunisticVTables) {
     assert(getVTables().isVTableExternal(RD) &&
            "This queue should only contain external vtables");
-    if (getCXXABI().canSpeculativelyEmitVTable(RD))
+    if (getCXXABI().canSpeculativelyEmitVTable(RD) &&
+        !RD->shouldEmitInExternalSource())
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efriedma-quic wrote:

Can you sink this check into canSpeculativelyEmitVTable()?  If we're not going to do available_externally vtables, I think the other callers of canSpeculativelyEmitVTable also want this check.

https://github.com/llvm/llvm-project/pull/75912