[PATCH] D140387: [clang][analyzer] Add stream related functions to StdLibraryFunctionsChecker.

[Balázs Kéri via Phabricator via cfe-commits]

balazske marked 5 inline comments as done.
balazske added a comment.

> I suppose the tests are done in the followup patch mostly?

Yes the tests in the next patch should cover the cases.



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Comment at: clang/lib/StaticAnalyzer/Checkers/StdLibraryFunctionsChecker.cpp:838
+  Result += getArgDesc(ArgN);
+  Result += DK == Violation ? " should not be zero" : " is not zero";
+  return Result.c_str();
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Szelethus wrote:
> I don't mean to make you test every single `Case` or `ArgumentConstraint` you added, but `NotZeroConstraint` is brand new, and is not tested anywhere.
This new class is probably not needed at all. It is always possible to use `ReturnValueCondition(WithinRange, SingleValue(0))` or similar for nonzero cases.


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Comment at: clang/lib/StaticAnalyzer/Checkers/StdLibraryFunctionsChecker.cpp:1105-1113
+      // It is possible that the function was evaluated in a checker callback
+      // where the state constraints are already applied, then no change happens
+      // here to the state (if the ErrnoConstraint did not change it either).
+      // If the evaluated function requires a NoteTag for errno change, it is
+      // added here.
+      if (const auto *D = dyn_cast_or_null<FunctionDecl>(Call.getDecl()))
+        if (const NoteTag *NT =
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Szelethus wrote:
> Can you name an example for that? `fgetpos`?
`fgetpos` is a good example, the return value is already bound and a state split for success and failure was performed in the `evalCall` function (in `StreamChecker`) and the previous line `Case.getErrnoConstraint().apply` did not create a new state (this is true for `fgetpos` because it has a `ErrnoUnchanged` condition in the summary).


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Comment at: clang/lib/StaticAnalyzer/Checkers/StdLibraryFunctionsChecker.cpp:1848-1849
+    // int fseek(FILE *stream, long offset, int whence);
+    // FIXME: It is possible to get the 'SEEK_' values (like EOFv) for arg 2
+    // condition.
+    addToFunctionSummaryMap(
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Szelethus wrote:
> Sure, but what should be fixed? We should check whether the the last argument is a `SEEK_*` value?
It could be an improvement to detect possible values for the argument 2 that are the `SEEK_*` values. Now the range [0,2] is used (the `SEEK_*` constants are usually 0,1,2).


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  https://reviews.llvm.org/D140387/new/

https://reviews.llvm.org/D140387