[clang] [clang][analyzer] Model more getline/getdelim pre and postconditions (PR #83027)

[Balázs Kéri via cfe-commits]

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@@ -1204,6 +1204,20 @@ void StreamChecker::evalGetdelim(const FnDescription *Desc,
         State->BindExpr(E.CE, C.getLocationContext(), RetVal);
     StateNotFailed =
         E.assumeBinOpNN(StateNotFailed, BO_GE, RetVal, E.getZeroVal(Call));
+    // The buffer size `*n` must be enough to hold the whole line, and
+    // greater than the return value, since it has to account for '\0'.
+    auto SizePtrSval = Call.getArgSVal(1);
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balazske wrote:

Probably this should not have type `auto` (it is used only if the real type is visible or the type name is very long).

https://github.com/llvm/llvm-project/pull/83027