[clang] [Sema] Check arg count for builtins with CustomTypeChecking (PR #222841)

[via cfe-commits]

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@@ -145,6 +145,16 @@ bool SemaPPC::CheckPPCBuiltinFunctionCall(const TargetInfo &TI,
   //  - IsIntType: enforces any integer type
   // Lambdas centralize type checks for BCD builtin handlers
 
+  // reject calls with more args than the builtin's declared prototype
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im-lunex wrote:

yup sure - if we are allowed to update the diagonstics then this should be butter smooth...

https://github.com/llvm/llvm-project/pull/222841