[clang] [ubsan] Assert that each check only has one SanitizerKind (PR #122392)

[Vitaly Buka via cfe-commits]

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@@ -3603,6 +3603,8 @@ void CodeGenFunction::EmitCheck(
   llvm::Value *TrapCond = nullptr;
   bool NoMerge = false;
   for (int i = 0, n = Checked.size(); i < n; ++i) {
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vitalybuka wrote:

Maybe instead switch SanitizerMask -> SanitizerOrdinal?

https://github.com/llvm/llvm-project/pull/122392