[llvm] [MSVC][Demangling] Respect MSDF_NoCallingConvention for function pointers (PR #209113)

[Fred Tingaud via llvm-commits]

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@@ -356,6 +356,10 @@ struct DEMANGLE_ABI FunctionSignatureNode : public TypeNode {
   void outputPre(OutputBuffer &OB, OutputFlags Flags) const override;
   void outputPost(OutputBuffer &OB, OutputFlags Flags) const override;
 
+  // Subpart of outputPre directly called by PointerTypeNode, in order to handle
+  // calling convention differently.
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frederic-tingaud-sonarsource wrote:

```suggestion
```

https://github.com/llvm/llvm-project/pull/209113