[clang] [Clang] Introduce OverflowBehaviorType for fine-grained overflow control (PR #148914)

[Eli Friedman via cfe-commits]

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@@ -1480,6 +1480,14 @@ class DeclRefExpr final
     return DeclRefExprBits.IsImmediateEscalating;
   }
 
+  bool isOverflowBehaviorDiscarded() const {
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efriedma-quic wrote:

Is there some description of what this bit is supposed to mean?  As far as I can tell, it tweaks the wording of one diagnostic?

https://github.com/llvm/llvm-project/pull/148914