[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:

cuz if we fix the double diagnostic issue by removing the checks and we dont need any more after removing "t" (already being handled by Sema's normal checking) we would have a different diagnostic message that the normal Sema will give us but that will need to update the diagnostic expectation of a lot of checks in many test files here.. 

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