[clang] [CIR] Upstream support for function/call calling conventions (PR #181170)

[Sirui Mu via cfe-commits]

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@@ -71,7 +71,7 @@ struct MissingFeatures {
   static bool opFuncArmNewAttr() { return false; }
   static bool opFuncArmStreamingAttr() { return false; }
   static bool opFuncAstDeclAttr() { return false; }
-  static bool opFuncCallingConv() { return false; }
+  static bool opFuncCallingConv() { return true; }
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Lancern wrote:

You could directly remove these missing functions.

https://github.com/llvm/llvm-project/pull/181170