[clang] Fix issue https://github.com/llvm/llvm-project/issues/98018. (PR #99672)

[Aaron Ballman via cfe-commits]

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@@ -8208,7 +8208,8 @@ void Sema::CheckInfNaNFunction(const CallExpr *Call,
         << 1 << 0 << Call->getSourceRange();
   else if ((IsStdFunction(FDecl, "isinf") ||
             (IsStdFunction(FDecl, "isfinite") ||
-             (FDecl->getIdentifier() && FDecl->getName() == "infinity"))) &&
+             (FDecl->getIdentifier() && FDecl->getName() == "infinity") ||
+             (Call->getBuiltinCallee() == Builtin::BI__builtin_inff))) &&
----------------
AaronBallman wrote:

What about the other `inf` builtins?
```
  case Builtin::BI__builtin_inf:
  case Builtin::BI__builtin_inff:
  case Builtin::BI__builtin_infl:
  case Builtin::BI__builtin_inff16:
  case Builtin::BI__builtin_inff128: {
```

https://github.com/llvm/llvm-project/pull/99672