[clang] [clang][analyzer] Model `strxfrm` (PR #156507)

[Alejandro Álvarez Ayllón via cfe-commits]

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@@ -2322,30 +2323,25 @@ void CStringChecker::evalStrxfrm(CheckerContext &C,
       StateSuccess = invalidateDestinationBufferBySize(
           C, StateSuccess, Dest.Expression, Call.getCFGElementRef(), DestVal,
           SizeVal, Size.Expression->getType());
-
-      StateSuccess = StateSuccess->BindExpr(Call.getOriginExpr(), LCtx, RetVal);
-      C.addTransition(StateSuccess);
+      BindReturnAndTransition(StateSuccess);
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alejandro-alvarez-sonarsource wrote:

Makes sense. I have reworked a bit these if/else to make clearer (I hope) the intent.

https://github.com/llvm/llvm-project/pull/156507