[clang] [CIR] Upstream __builtin_creal for ComplexType (PR #146927)

[Erich Keane via cfe-commits]

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@@ -192,6 +196,13 @@ RValue CIRGenFunction::emitBuiltinExpr(const GlobalDecl &gd, unsigned builtinID,
   }
   }
 
+  // If this is an alias for a lib function (e.g. __builtin_sin), emit
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erichkeane wrote:

We should have @andykaylor take a look at this, this was a good way to get a bunch of stuff passing by ignoring the above code for most of these, so I don't know how much this will harm us.  But overall it looks reasonable to me.

https://github.com/llvm/llvm-project/pull/146927