Summary:
Litho uses an idiom as follows. `Component.Builder` has an abstract method `T getThis()` which is supposed to be implemented as `{return this;}`.
I believe the reason it's there is to have covariant return types in subclasses, though this doesn't really matter.
We don't do dynamic dispatch, so instead of summarising `getThis` as having a return ownership of `OwnedIf({ 0 })` we just return `Unowned`.
This is generating many false positives, which are really hard to debug.
Here I'm special-casing any abstract method whose return type is equal to that of it's only argument, to return conditional ownership.
Reviewed By: da319
Differential Revision: D8947992
fbshipit-source-id: 33c7e952d
Summary: Exceptional successors were not meant to be created for return nodes, but they were created if try block had a single return statement.
Reviewed By: jvillard
Differential Revision: D8913371
fbshipit-source-id: 6ac85b21d
Summary:
Currently, some blocking calls are turning up too many false positives. Adjust severities by fix rate/preexisting numbers.
Also, restrict some calls to exact class, as opposed to superclasses.
Reviewed By: mbouaziz
Differential Revision: D8850599
fbshipit-source-id: 47543d04a
Summary:
It adds relational domains to Inferbo: octagon of Apron and polyhedra of Elina.
- Each `Mem` domain value includes one relational value containing relations among *symbols*. The relational values are modified by the `Prune` and `Store` commands.
- Each abstract value includes three *symbols*, which represent integer value, array offset, and array size of an abstract value.
The relational domain is deactivated by default, so this diff should not make any differences in CI.
Use `--bo-relational-domain {oct, poly}` for the activation, though Inferbo with the relational domains does not work at this point because some modifications of Apron and Elina we made has not been applied to their opam repositories yet.
Reviewed By: mbouaziz, jvillard
Differential Revision: D8478542
fbshipit-source-id: 510ff53
Summary:
Do no computation of stability abstract state if not explicitly requested via the command line flag.
Also, simplify the reporting.
Reviewed By: jeremydubreil
Differential Revision: D8614885
fbshipit-source-id: 25dd9de
Summary:
The addresses of global variables do not need initialisation to exist and be valid as they are part of the code or data segment of the program. This means that taking the address of a global is not in itself a danger for SIOF. However, dereferencing such an address would be. In order to avoid false positives but avoid being too unsound, only ignore them when the address is taken only to set another global. The general case would require a more complicated abstract domain.
Fixes#866
Reviewed By: ngorogiannis
Differential Revision: D8055627
fbshipit-source-id: 92307b2
Summary:
These just point to expressions that we know how to translate.
Fixes#950
Reviewed By: mbouaziz
Differential Revision: D8713784
fbshipit-source-id: 9eafa39
Summary: The frontend got better and now `assert` is correctly translated.
Reviewed By: dulmarod
Differential Revision: D8731877
fbshipit-source-id: ba11b0c
Summary:
- Do not add actuals of a call as unstable.
- Replace access trie with simple set of paths, which is easier to debug/argue correct.
- Fix bug where a prefix path was searched, as opposed to a *proper* prefix.
- Restrict interface to the minimum so that alternative implementations are easier.
Reviewed By: ilyasergey
Differential Revision: D8573792
fbshipit-source-id: 4c4e174
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: Trying to convert a large int literal to an OCaml int raises an exception. The use case here actually needed a float anyway, so add an API for that.
Reviewed By: jeremydubreil
Differential Revision: D8550410
fbshipit-source-id: 382495b
Summary: Record that it is not supported: https://github.com/facebook/infer/issues/8
Reviewed By: mbouaziz, dulmarod
Differential Revision: D8442762
fbshipit-source-id: fa271cb
Summary:
I realized that control variable analysis was broken when we had multiple back-edges for the same loop. This is often the case when we have a switch statement combined with continue in a loop (see `test_switch` in `switch_continue.c`) or when we have disjunctive guards in do-while loops.
This diff fixes that by
- defining a loop by its loophead (the target of its backedges) rather than its back-edges. Then it converts back-edge list to a map from loop_head to sources of the loop's back-edges.
- collecting multiple guard nodes that come from potentially multiple exit nodes per loop head
In addition, it also removes the wrong assumption that an exit node belongs to a single loop head.
Reviewed By: mbouaziz
Differential Revision: D8398061
fbshipit-source-id: abaf288
Summary:
We need to report on non-private methods (the opposite even leads to FPs sometimes on deadlocks). To do this, the domain needs to change so that the interpretation of an order pair `a,b` is no longer "lock `a` is taken in the *current method* and held until lock `b` is taken". Instead the meaning is now "lock `a` is taken in some method *of the same class with the current method* and is held until `b` is taken".
These changes are quite drastic because the previous implementation optimised extensively around the previous use case.
Reviewed By: mbouaziz
Differential Revision: D8395351
fbshipit-source-id: a2bd22b
Summary:
The deadlock reports (the actual string) were too low level, in order to avoid bug hash clashes. Now that we deduplicate this is less of an issue, so it's an opportunity to improve readability.
```
Potential deadlock.
Trace 1 (starts at `void Interproc.interproc1Bad(InterprocA)`) first locks `this` in class `Interproc*` (line 9 in `void Interproc.interproc1Bad(InterprocA)`) and then locks `b` in class `InterprocA*` (line 14 in `void Interproc.interproc2Bad(InterprocA)`).
Trace 2 (starts at `void InterprocA.interproc1Bad(Interproc)`), first locks `this` in class `InterprocA*` (line 37 in `void InterprocA.interproc1Bad(Interproc)`) and then locks `d` in class `Interproc*` (line 42 in `void InterprocA.interproc2Bad(Interproc)`).
```
Reviewed By: mbouaziz
Differential Revision: D8394978
fbshipit-source-id: 671ccb0
Summary:
The deadlock reports (the actual string) were too low level, in order to avoid bug hash clashes. Now that we deduplicate this is less of an issue, so it's an opportunity to improve readability.
```
Potential deadlock.
Trace 1 (starts at `void Interproc.interproc1Bad(InterprocA)`) first locks `this` in class `Interproc*` (line 9 in `void Interproc.interproc1Bad(InterprocA)`) and then locks `b` in class `InterprocA*` (line 14 in `void Interproc.interproc2Bad(InterprocA)`).
Trace 2 (starts at `void InterprocA.interproc1Bad(Interproc)`), first locks `this` in class `InterprocA*` (line 37 in `void InterprocA.interproc1Bad(Interproc)`) and then locks `d` in class `Interproc*` (line 42 in `void InterprocA.interproc2Bad(Interproc)`).
```
Reviewed By: mbouaziz
Differential Revision: D8379328
fbshipit-source-id: bc33983
Summary: Deadlocks can be very noisy, so dedup reports on same line by showing only the one with the shortest trace and a count of the suppressed ones.
Reviewed By: mbouaziz
Differential Revision: D8351148
fbshipit-source-id: 8913db2
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