Summary:
This diff adds a false positive test that is introduced imprecise loop
invariant detection.
In the example, `i` and a temp variable `$irvar = get_size(arr)` are
all included in the control variables, so the complexity becomes
quadratic. The problem is that `$irvar` is not addressed as a loop
invariant:
* `is.read` is analyzed as modifying a global
* all return variables, including `$irvar`, of unmodeled functions are invalidated
Reviewed By: ezgicicek
Differential Revision: D23051414
fbshipit-source-id: 011fd086b
Summary: To avoid dead store false positives we skip initialization of a variable that has an `unused` attribute. However, this causes uninitialized value false positives when the variable is later used in macros. To fix this, instead of skipping initialization we record the information about `unused` attribute in local variable data that we can later use for filtering out dead store issues.
Reviewed By: jvillard
Differential Revision: D22868050
fbshipit-source-id: 4a2d0e680
Summary:
In the current implementation, we record 3 states: modelled internally,
modelled intenally, not modelled.
The follow up diffs will need to distinct first- and third- party, given
annotated signature. This diff makes it possible.
Reviewed By: artempyanykh
Differential Revision: D22977962
fbshipit-source-id: b8f3616b5
Summary:
We get duplicated variable declaration instruction for primitive type variable initialized using list initializer, e.g.
```
int* p{nullptr};
```
This happens because we add variable declaration instruction when we translate both `DeclStmt` and `InitListExpr`. To fix this, we do not add the duplicated variable declaration when we translate `InitListExpr`.
Reviewed By: jvillard
Differential Revision: D22844726
fbshipit-source-id: 422806924
Summary:
Synthetic/autogenerated methods/fields usually contain `$` in their names.
Reporting nullability violations on such code doesn't make much sense
since the violations are not actionable for users and likely need to be
resolved on another level.
This diff contributes:
1. Several test cases that involve synthetic code of different
complexity.
2. Code that handles some particular types of errors (but not all!).
Reviewed By: mityal
Differential Revision: D22984578
fbshipit-source-id: d25806209
Summary:
Use `Typ.t` for parameter types in procnames, instead of `JavaSplitName.t`. This allows more precise and usable types stored in procnames, as well as not using the string-based representation of `JavaSplitName` which meant parsing strings whenever one needed a `Typ.t`.
This also makes `JavaSplitName` dead code, so it is removed.
Reviewed By: skcho
Differential Revision: D20500423
fbshipit-source-id: a72728e3f
Summary: Since types from the java frontend are a subtype of `Typ.t` provide the means to check and enforce that for return types in procnames.
Reviewed By: ezgicicek
Differential Revision: D20495527
fbshipit-source-id: b99c784af
Summary:
`java_type` aka `JavaSplitName.t` is a pair of strings. It's used in a procname to store the return type. Replace that with `Typ.t`.
This is step one of deleting `JavaSplitName`. Step two will be to replace parameters with `Typ.t`.
Reviewed By: skcho
Differential Revision: D20323748
fbshipit-source-id: f0029c3ca
Summary:
This diff adds an option `max-jobs` that restrict the number of jobs
running simultaneously.
Reviewed By: ngorogiannis
Differential Revision: D22978328
fbshipit-source-id: 544153c1c
Summary:
Currently, the notion of a third party method signature (corresponding to
a single record in a .sig file) is scattered between unique_repr and
nullability.
Logically, ThirdPartyMethod.t should not "know" about unique_repr
because this is a detail needed only for searching for a method
definition in `.sig` storage.
This diff:
1. Introduces ThirdPartyMethod.t which exposes exactly information
stored in .sig file. We are going to use this abstraction more in follow
up diffs.
2. Moves functionality operating with `unique_repr` to the module
responsible for searching in the repository.
3. Deletes `ThirdPartyMethod.nullability` abstraction - we don't need it as we can just store ThirdPartyMethod.t where was previously `nullability` stored.
4. Introduces `to_canonical_string` method that prints back third party
method in a format needed for `.sig` file, and a test ensuring that
parsing works back and forth consistently. We are going to use this
method in follow up diffs as well.
Reviewed By: artempyanykh
Differential Revision: D22950706
fbshipit-source-id: a0e72ccdb
Summary: As per title. Eases next diffs by making Summary the only source of truth for how spec files are accessed/stored.
Reviewed By: ezgicicek
Differential Revision: D22794742
fbshipit-source-id: 0ee20ec1c
Summary: New, experimental for now, integration with buck on Java using the `#infer-java-capture` flavor.
Reviewed By: artempyanykh
Differential Revision: D22187748
fbshipit-source-id: 62cdafe6b
Summary:
This diff removes a dead field `Struct.subs`, which was used in
heuristics finding methods from sub-classes.
Reviewed By: ezgicicek
Differential Revision: D22945346
fbshipit-source-id: 4b3bf0093
Summary: This diff is on par with this change, with the same motivation
Reviewed By: artempyanykh
Differential Revision: D22924891
fbshipit-source-id: 578ca5869
Summary:
This change will simplify the further refactoring I am doing in follow
up diffs.
Logically, AssignmentRule is about passing actual value to the declared
one, and the proper abstactions for this is exactly AnnotatedNullability
and InferredNullability.
This will also make the client less error prone (no way to call if you
don't have a declaration and actual value to compare).
In the next diff, we will do the same in DereferenceRule.
Reviewed By: artempyanykh
Differential Revision: D22923779
fbshipit-source-id: 5f8f0931c
Summary: Before, `NSCollection` are modelled like array, but this will have issue when we want to say add object to array. This diff changes `NSCollection`'s model to use Java's Collection model.
Reviewed By: ezgicicek
Differential Revision: D22840079
fbshipit-source-id: b944b743b
Summary:
In Cost/Inferbo checkers, it tried to find a subclass with heuristics when a method of interface or
abstract class is called. While it makes preciser analysis results in general, sometimes introduced
tricky FPs since the behavior of the heuristics depends on targets. This diff revert the heuristics
to suppress the FPs.
Reviewed By: ngorogiannis
Differential Revision: D22924485
fbshipit-source-id: 9f151231f
Summary: Implement `alloc` and implement initialisation method that uses the return value of `alloc`, i.e. `NSString.init`.
Reviewed By: ezgicicek
Differential Revision: D22840080
fbshipit-source-id: 47a7523e3
Summary:
This diff translates for-in block in objc as a simple for-loop. For example,
`for (item_type item in items) { body }` is translated to
```
NSEnumerator *enumerator = [items objectEnumerator];
item_type item;
while (item = [enumerator nextObject]) { body }
```
Reviewed By: ezgicicek
Differential Revision: D22841524
fbshipit-source-id: 296ee84df
Summary:
Capture of certain Kotlin files fails at the javalib level (probably,
some unanticipated bytecode pattern). We however can't just completely
skip Kotlin class-files during capture as those have NotNull/Nullable
annotations on methods/params that are important for Java <- Kotlin
interop (using Kt classes from Java).
Instead we can skip translation of concrete methods from Kotlin classes
while retaining method signatures with annots in the TEnv.
Reviewed By: ngorogiannis
Differential Revision: D22897638
fbshipit-source-id: 67909aa43
Summary:
There are two ways to suppress it.
1. Field level suppression annotation (was already tested). This will
apply to all constructors.
2. Constructor level annotation (this is what this test does). Sometimes
there are "fake" constructors that are not intended to be called in
prod, they might leave some fields not initialized.
Note that there are two ways to add a suppression; one has a known
problem that is documented here.
Reviewed By: artempyanykh
Differential Revision: D22864869
fbshipit-source-id: f95aaa26a
Summary: `alloc` actually allocates the array, not the `init`. Let's reflect that in our models.
Reviewed By: roro47
Differential Revision: D22864198
fbshipit-source-id: 687f9f247
Summary:
It's typically used inside another ~fold argument and it gets too
verbose.
Reviewed By: da319
Differential Revision: D22846501
fbshipit-source-id: 2fdd4271f
Summary: `Array.copyOf` model has nothing to do with Collections. Refactor it to the appropriate place
Reviewed By: roro47
Differential Revision: D22844638
fbshipit-source-id: 48dde4d53
Summary:
When expressions use generics or typecasts, CFG contains intermediate `_fun_cast` nodes which break some nullsafe heuristics and lead to false positives.
This affects different types of checks (null-check on assignment expressions, `map.containsKey` checks in assignment expressions, regular typecasts, etc.
See added tests for examples.
Reviewed By: mityal
Differential Revision: D22815631
fbshipit-source-id: 80d444b1c
Summary:
We check for supertypes in Java. Why not ObjC?
Would be good to get dulmarod's input here.
Reviewed By: roro47
Differential Revision: D22817126
fbshipit-source-id: 52c1c3f3c
Summary: This diff adds an option to shard spec files in `infer-out/specs`. For some big analysis targets, there can be too many of spec files in the one directory, which slows down IO speed for reading the spec files.
Reviewed By: jvillard
Differential Revision: D20002128
fbshipit-source-id: bd7722883
Summary: There used to be `JoinAfter n` mode where we would try to join `n` states instead of always making disjunctions. It got deleted in D14258485 and Pulse's underlying (pre-disjuncts) domain doesn't even have a join operation. `NeverJoin` mode is not useful in Pulse anymore: pulse will diverge or OOM if we don't limit the number of disjuncts. It is also not used by any other analyzer. Let's remove it.
Reviewed By: jvillard
Differential Revision: D22817425
fbshipit-source-id: 1e658f11d
Summary: This diff refactors Java specific `PatternMatch` functions into its own module. When `PatternMatch.ml` was originally created, it was mainly for Java but now it also supports ObjC. Let's refactor it to reflect the Java/ObjC separation: move all functions that operate on Java procnames into Java submodule.
Reviewed By: jvillard
Differential Revision: D22816504
fbshipit-source-id: ff6b64b29
Summary:
This avoids wasting potentially large amount of work in some
pathological situations. Suppose `foo()` has D specs/disjuncts in its
Pulse summary, and consider a node that calls `foo()` N times, starting
with just one disjunct:
```
[x]
foo()
[x1, ..., xD]
foo()
[y1, ..., yD^2]
foo()
...
```
At the end we get `D^N` disjuncts. Except, currently (before this diff),
we prune the number of disjuncts to the limit L at each step, so really
what happens is that we (very) quickly reach the L limit, then perform
`L*D` work at each step (where we take "apply one pre/post pair to the
current state" to be one unit of work), thus doing `O(L*D*n)` amount of
work.
Instead, this diff counts how many disjuncts we get after each
instruction is executed, and we already reched the limit L then doesn't
bother accumulating more disjuncts (as they'd get discarded any way),
and crucially also doesn't bother executing the current instruction on
these extra disjuncts. This means we only do `O(L*n)` work now, which is
exactly how we expect pulse to scale: execute each instruction (in
loop-free code) at most L times.
This helps with new arithmetic domains that are more expensive and
exhibit huge slowdowns without this diff but no slowdown with this diff
(at least on a few examples).
Reviewed By: skcho
Differential Revision: D22815241
fbshipit-source-id: ce9928e7c
Summary:
The old --topl-only is now --topl-biabd-only, and there's also
--topl-pulse-only. This is WIP: the latter runs pulse, but it doesn't yet
extract Topl errors from pulse summaries. (The citv part of pulse path
conditions appears to have the necessary information.)
Reviewed By: jvillard
Differential Revision: D22815250
fbshipit-source-id: a01792945
Summary:
This diff:
1. Adds general capability to model any field as nullable /
non-nullable.
2. Uses it for Boolean.TRUE and Boolean.FALSE
Reviewed By: artempyanykh
Differential Revision: D22794226
fbshipit-source-id: 95f586592
Summary: D17500386 had added the ability to give symbolic values on functions returning exceptions. However, this might cause FPs or cryptic complexity reports (especially with subclass heuristics). This diff aims to revert it back.
Reviewed By: skcho
Differential Revision: D22764266
fbshipit-source-id: 1615544d8
Summary: We model internal builtin `__new` function to return a non-null value. This fixes nullptr_dereference false positives where we explicitly check the result of a function call for nullptr when the function returns a newly created object.
Reviewed By: jvillard
Differential Revision: D22772217
fbshipit-source-id: 37d209697
Summary:
This stopped compiling on my Debian and it seems hard to fix. It was
already having compilation issues between osx and Linux but here I don't
know how to detect which type it wants since the OS is Linux too.
Reviewed By: ezgicicek
Differential Revision: D22728282
fbshipit-source-id: 818ae87e6
Summary:
This step does extra normalization so it's useful to see what's going on
when debugging. Log stuff in the html debug of the exit node.
Reviewed By: da319
Differential Revision: D22596248
fbshipit-source-id: cde3bbb6c
Summary:
Pulse has models for iterators that make them use a fake field to
remember the element of the collection they point to. But, not all
methods are modelled, and some of them look at the real field, eg
`operator==`. Since we don't update the real field in the model, this
causes imprecision.
The imprecision was visible in pudge.
Reviewed By: skcho
Differential Revision: D22576003
fbshipit-source-id: 2af6be646
Summary:
The java frontend used an unsound flow insensitive class analysis to devirtualize
some virtual calls. We remove it and let the recent devirtualizer preanalysis do the job.
This unsoudness in the Java frontend may have been here for a long time. Removing it may
modify several analysis results (specially Nullsafe) where virtual calls may look different
now.
Reviewed By: jvillard
Differential Revision: D22662739
fbshipit-source-id: c45296dce
Summary:
Changing the order of the superclasses of a struct exposes a bug in both biabduction and the devirtualiser where a method would be resolved into a still virtual method (an interface method).
The reason is that we don't check whether a super class is an interface before exploring it, and seemingly we assume that there is only one (first) superclass worth exploring. This also ignores multiple inheritance in C++.
To fix this, refactor the resolution to a complete search (not just the first super class!) which ignores Java interface methods. Also moved it to `Tenv` so that both biabduction and the devirtualiser can use it.
Reviewed By: jvillard
Differential Revision: D22357488
fbshipit-source-id: 54b96c1f4
Sungkeun Cho
Daiva Naudziuniene
Mitya Lyubarskiy
Artem Pianykh
Nikos Gorogiannis
Qianyi Shu
Ezgi Çiçek
Jules Villard
Radu Grigore
David Pichardie