[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:

i think removing "t" will get it duplicate diagnostics that's why .. ? yeah this might be cause cuz:

The `isTSBuiltin` branch is unconditional, It runs for every TS builtin regardless of "t". So `CheckPPCBuiltinFunctionCall` always executes and when "t" is absent that normal type-checking is not suppressed, so it emits generic C-like diagnostics.

soo when we had "t" included it didnt apply the prototype-based checks

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