Summary: C/C++ code can, in some cases, generate a large number of temporary (Sil) variables. Since we are already not reporting races on these, not recording them gives some perf back.
Reviewed By: mbouaziz, jvillard
Differential Revision: D8566999
fbshipit-source-id: 148ac46
Summary: We were missing reads of `a` if it was used in void cast, i.e. `(void) a;` This caused dead store false positives: we were not using `exp` that was the result of translating `a`. This diff creates a call to built-in skip function with `exp` as its argument, which causes the analyses to see reads of `exp`.
Reviewed By: mbouaziz
Differential Revision: D8332092
fbshipit-source-id: f3b0e10
Summary: There is a number of dangling pointer dereference false positives coming from our treatment of union in c/cpp. For now, do not treat union fields as uninitialised.
Reviewed By: mbouaziz
Differential Revision: D8279802
fbshipit-source-id: a339b0e
Summary: We get a lot of false positives for union types as union fields are treated as separate memory locations at the moment. For now we do not treat union fields as uninitialised.
Reviewed By: mbouaziz
Differential Revision: D8277363
fbshipit-source-id: efe5b4a
Summary:
It's useful to test that the bucket a given error is classified as doesn't
change over time without notice.
This records the bucket for *all* the tests, even though some never produce a
bucket. This is to be on the safe size instead of risking to forget adding the
bucket information when the test changes, or when copy/pasting from a test that
doesn't have buckets to one that does.
The implementation is pretty crude: it greps the beginning of the qualifier
string for a `[bucket]`.
Reviewed By: mbouaziz
Differential Revision: D8236393
fbshipit-source-id: b3b1eb9
Summary:
Change the license of the source code from BSD + PATENTS to MIT.
Change `checkCopyright` to reflect the new license and learn some new file
types.
Generated with:
```
git grep BSD | xargs -n 1 ./scripts/checkCopyright -i
```
Reviewed By: jeremydubreil, mbouaziz, jberdine
Differential Revision: D8071249
fbshipit-source-id: 97ca23a
Summary:
Moving away from C++ include-based models means that we cannot reliably detect
anymore whether a file includes <iostream> or not. In order not to be too
spammy, let's always assume standard streams are initialized for now when the
include models are off.
Recent versions of libstdc++ make these models redundant so there is hope that in a
bright future the analysis of std streams initialisation will work correctly without infer
having to have its own models anyway.
Reviewed By: mbouaziz
Differential Revision: D8043467
fbshipit-source-id: d118043
Summary: Treat array accesses as initialised if they are passed by reference.
Reviewed By: jvillard
Differential Revision: D8071247
fbshipit-source-id: 5480e90
Summary: Use AccessExpressions instead of AccessPath in uninit analysis. This will allow us to distinguish between pointers and their dereferences.
Reviewed By: jvillard
Differential Revision: D8042359
fbshipit-source-id: 604bcbc
Summary:
Labels inside switch statements were causing havoc (see test), and the translation of switch statements in general could be improved to handle more cases.
It turns out that `case` (and `default`) statements are more or less fancy labels into the code. In other words, if you erase all the `case XXX:` and `default:` strings in the `switch` statement you get the real structure of the program, and `switch` just jumps straight to the first `case` directives (and to the second if the first one is not satisfied, etc. until all `case`/`default` have been considered).
This suggests an alternative implementation: translate the body of the `switch` and simply record the list of switch cases inside that body, along with where they point to. Then post-process this list to construct the control flow of the `switch`, which points into the control-flow of the `body`. In order not to modify every function in `CTrans` to propagate the current list of cases, I created an ugly `ref` inside `SwitchCase` instead (but it cannot be directly accessed and it's guaranteed to be well-parenthesised wrt nested switches by the `SwitchCase` API so it's not too bad).
[unrelated] Also make translation failures output more information about what exactly in the source code is causing the crash, and the ancestors in the AST that lead to the crash site.
Reviewed By: martinoluca
Differential Revision: D8011046
fbshipit-source-id: 8455090
Summary:
This diff:
- translates C++ `catch` blocks
- adds an exceptional control-flow edge from the end of a `try` block to the beginning of a `catch` block
This obviously doesn't reflect the way exceptions actually work, but I think it is better than what we have now. For one thing, we'll see/translate code inside `catch` blocks, which were opaque before. If Clang analyses don't want this behavior, they can simply use `ProcCfg.Normal` (which, up until this diff, behaved identically to `ProcCfg.Exceptional`.
In the future, we can extend `trans_state` to track blocks that might throw an exception, and have each of these blocks transition to `catch` instead.
Reviewed By: jvillard
Differential Revision: D7814521
fbshipit-source-id: 67b86a6
Summary:
Previously, the type of `trans_result` contained a list of SIL expressions.
However, most of the time we expect to get exactly one, and getting a different
number is a soft(!) error, usually returning `-1`.
This splits `trans_result` into `control`, which contains the information
needed for temporary computation (hence when we don't necessarily know the
return value yet), and a new version of `trans_result` that includes `control`,
the previous `exps` list but replaced by a single `return` expression instead,
and a couple other values that made sense to move out of `control`. This allows
some flexibility in the frontend compared to enforcing exactly one return
expression always: if they are not known yet we stick to `control` instead (see
eg `compute_controls_to_parent`).
This creates more garbage temporary identifiers, however they do not show up in
the final cfg. Instead, we see that temporary IDs are now often not
consecutive...
The most painful complication is in the treatment of `DeclRefExpr`, which was
actually returning *two* expressions: the method name and the `this` object.
Now the method name is a separate (optional) field in `trans_result`.
Reviewed By: mbouaziz
Differential Revision: D7881088
fbshipit-source-id: 41ad3b5
Summary:
This is an attempt to make things more consistent, and maybe save some work
from the `Format` module in case flambda doesn't have our backs.
Reviewed By: jberdine
Differential Revision: D7775496
fbshipit-source-id: 59a6314
Summary: std::lock allows for locking multiple lockable objects, while avoiding deadlock. This will fix some FPs in C++.
Reviewed By: da319
Differential Revision: D7844198
fbshipit-source-id: 2b7140a
Summary:
This simplifies the frontends and backends in most cases. Before this diff,
returning `void` could be modelled either with a `None` return, or a dummy
return variable with type `Tvoid`. Now it's always the latter.
Reviewed By: sblackshear, dulmarod
Differential Revision: D7832938
fbshipit-source-id: 0a403d1
Summary: Returning the list of sub-expressions is not right and can cause assertion failures elsewhere in the frontend.
Reviewed By: dulmarod
Differential Revision: D7813493
fbshipit-source-id: 33ac9c1
Summary:
When looking at large CFGs, at least in `xdot`, it's often difficult to find
the procedure you're looking for. Sorting the proc names puts them in
alphabetical order, which makes searching one procedure easier.
Reviewed By: mbouaziz
Differential Revision: D7758521
fbshipit-source-id: 8e9997f
Summary: Currently when we look for already abduced expression and find an assertion [exp|->strexp:typexp], we use typexp rather than strexp.
Reviewed By: sblackshear
Differential Revision: D7617193
fbshipit-source-id: c089720
Summary:
This information is already available in the trace, and can contain absolute
paths to system includes (or infer's own clang runtime), which confuses the
diff analysis.
Reviewed By: mbouaziz
Differential Revision: D7534609
fbshipit-source-id: 5bd8f8b
Summary:
If an aggregate `a` has a field `f` whose type has a constructor (e.g., `std::string`), we translate creating a local aggregate `A { "hi" }` as `string(&(a.f), "hi")`.
This diff makes sure that we recognize this as initializing `a`.
Reviewed By: jeremydubreil
Differential Revision: D7404624
fbshipit-source-id: 0ba90a7
Nikos Gorogiannis
Dulma Churchill
Daiva Naudziuniene
Jules Villard
Sam Blackshear
Oliver Castillo
Ezgi Çiçek
Dino Distefano
Mehdi Bouaziz
Sungkeun Cho