Summary:
Assume that std::vector::resize will always create nonempty vector. While this is clearly
wrong for resize(0), it removes many FPs for `resize(n)` calls, where value of `n` is unknown.
Without it, infer was thinking that `n` could be 0 and reported empty vector access.
Reviewed By: jvillard
Differential Revision: D3424355
fbshipit-source-id: cb476de
Summary:
Array types where the length is not statically known were represented
using fresh variables. This diff:
- Makes array type length optional, reducing the amount of work needed
for renaming, substitution, and normalization.
- Revises uses of array length so that the length component of a
Tarray type represents only the statically determined constant
length of an array type, and the length component of a Sizeof
expression represents the dynamically determined length of an array
value.
- Restricts the type of static lengths from a general expression
(Sil.exp) to an integer (Sil.Int.t), enforcing that static types are
constant. This in particular ensures that types contain no
variables, and so are invariant under operations such as renaming
and substitution.
- Removes the type substitution and renaming functions typ_sub,
typ_normalize, and typ_captured_ren. Now that array type lengths
are constant integers, all of these functions are the identity.
Reviewed By: cristianoc
Differential Revision: D3387343
fbshipit-source-id: b5db768
Summary:
The extra dereference in stmtexpr was wrong. When a dereference is needed, we have a cast.
This was causing one dereference too many, and creating wrong results.
Reviewed By: akotulski
Differential Revision: D3393294
fbshipit-source-id: 7a1ec8e
Summary:
Pass object by reference every time struct object is passed by value
in C++. Do it only for C++/objC++ where we have guarantee that the
object which is passed will be temporary one (created by copy constructor).
Reviewed By: jberdine
Differential Revision: D3346271
fbshipit-source-id: d3e5daa
Summary:
Make analyzer find out when null dereference comes from std::vector method.
If it does, it means that it's really empty vector access (due to the
way infer models std::vector)
Reviewed By: sblackshear
Differential Revision: D3327933
fbshipit-source-id: b9e11d6
Summary:
Turns out, analyzer was getting confused with complicated
model and it was reporting empty access in places it
shouldn't. Fixing backend is not trivial (tracing mode is the answer),
but the model can be simplified.
It introduces the problem that get() method doesn't return fresh value
every time, but we should be able to change backend later to deal with it.
Reviewed By: sblackshear
Differential Revision: D3328228
fbshipit-source-id: dddbaf8
Summary:
Create model of C++ std::vector to find occurrences when vector which might be empty is accessed. Do it by triggering null dereference every time empty vector access is performed.
Note: model will be used only when c++11 (or c++14) are used.
Reviewed By: sblackshear
Differential Revision: D3276203
fbshipit-source-id: 420a95a
Summary:
The philosophy of the tracing mode reporting is to not report the errors in a method if reaching this error does depend on information that can be false at call site. Typically with:
void foo(Object obj, int x) {
if (x == 3) {
obj.toString();
}
}
it may be that we always call `foo` with a non-null parameter or `x != 3`.
Thechnically, the reporting code matches the pairs of the form (precondition, error) and filtering out the cases where the precondtions was not imposing constraints on the calling context, and report the other cases. So the NPE could be reported in the following case:
void bar() {
foo(null, 3);
}
However, we were missing the case where there was anyway no way to call a method in a safe way, i.e. all the preconditions were of the form: (precondition, error), for example:
void baz(boolean b) {
if (b) {
foo(null, 3);
} else {
foo(null, 3);
}
}
In that case, the summary is of the form
PRE (1): b = false
POST: NullPointerException
PRE (2): b = true
POST: NullPointerException
In which case it is legit to report `NullPointerException` in `baz`.
Reviewed By: sblackshear, jberdine
Differential Revision: D3220501
fb-gh-sync-id: 7fb7d70
fbshipit-source-id: 7fb7d70
Summary: Example of dynamic dispatch with interfaces were already working. Adding some tests now so that we don't break this.
Reviewed By: sblackshear
Differential Revision: D3220360
fb-gh-sync-id: 11395dd
fbshipit-source-id: 11395dd
Summary: For performance critical sections of the code, this checker detects memory allocations or calls to methods annotated as expensive. However, such cases of memory allocations or expensive calls are acceptable is occuring in rare cases. This diff adds supports for the "unlikely" branch prediction method and does not track expensive calls in unlikely branches.
Reviewed By: sblackshear
Differential Revision: D3193473
fb-gh-sync-id: ea87e49
fbshipit-source-id: ea87e49
Summary:BinaryConditionalOperator should evaluate condition expression once, but we used to evaluate it twice.
Fix translation to account for it.
Reviewed By: dulmarod
Differential Revision: D3179803
fb-gh-sync-id: a801a7e
fbshipit-source-id: a801a7e
Summary:This diff translate cpp lambdas. For the moment it does not take care of
captured variables. Captured variables will come in the next diff.
Reviewed By: dulmarod
Differential Revision: D3114790
fb-gh-sync-id: bf36450
fbshipit-source-id: bf36450
Summary:public
When a conditional is the last instruction, there will be a join node leading directly to the exit node.
Some instructions, such as nullification of dead variables, and abstraction, are added to the control flow graph automatically. But, join nodes cannot contain instructions. So when a procedure ends with a conditional, there might be no place to store these instructions.
This diff adds one extra node between the join and the exit node in that situation.
Reviewed By: jvillard
Differential Revision: D3179056
fb-gh-sync-id: 2b9cd7e
fbshipit-source-id: 2b9cd7e
Summary:public
Add modeling of methods that can raise exceptions when parameters are
nil, and that return nil when passed nil.
Reviewed By: dulmarod
Differential Revision: D3101739
fb-gh-sync-id: 76af5a2
fbshipit-source-id: 76af5a2
Summary:public
Create a model of std::unique_ptr in similar fashion to what was done to std::shared_ptr.
For now, we are modeling it as container of raw pointer (no ownership concept).
This time unique_ptr is not derived from std__unique_ptr (unlike shared_ptr, it was easier to not do that) and so we need to provide implementations for all non-member functions per C++ reference:
http://en.cppreference.com/w/cpp/memory/unique_ptr
Reviewed By: dulmarod
Differential Revision: D3048209
fb-gh-sync-id: a9a6455
shipit-source-id: a9a6455
Summary:public
Before this diff, the Java frontend was not adding the definition of the inherited interfaces to the type environment, thus failing to answer questions like "does type X implements Closeable". Infer was therefore missing to detect resource leaks when the resource was indirectly implementing Closeable via an intermediate interface.
Reviewed By: sblackshear
Differential Revision: D3067555
fb-gh-sync-id: 86d0760
shipit-source-id: 86d0760
Summary:public
Implementation of std::move is straightforward and infer understands it without
any problems. To use it, we translate it even though it's coming from system headers.
Reviewed By: jvillard
Differential Revision: D3064019
fb-gh-sync-id: 823ae75
shipit-source-id: 823ae75
Summary:This pull request adds the SuppressViewNullability annotation.
The reasoning behind this is that in libraries, one cannot use Butterknife for view binding, which forces you to do it manually. Basically, this makes a new annotation that infer treats the same way as Bind/InjectView
Closes https://github.com/facebook/infer/pull/301
Reviewed By: jvillard
Differential Revision: D3047235
Pulled By: cristianoc
fb-gh-sync-id: 6286d2b
shipit-source-id: 6286d2b
Summary:public
Create initial model of C++ std::shared_ptr. This means that infer will replace implementation of
shared_ptr and the resulting binary will change. Make sure no one will run it by crashing any binary that includes that code.
Reviewed By: jvillard
Differential Revision: D2999948
fb-gh-sync-id: 5753559
shipit-source-id: 5753559
Summary:public This also required a refactoring of InitListExpr.
The idea is that ImplicitValueInitExpr can stand for initialising a whole struct,
so we translating as a list of zero expressions, according to the struct's fields,
which is then paired with a list of field expressions, such that one get a list of
assignment instructions.
Reviewed By: ddino
Differential Revision: D2999875
fb-gh-sync-id: 7f609a0
shipit-source-id: 7f609a0
Summary:public
Lazy dynamic dispatch handling works as follows:
Assuming a call of the form:
foo(a);
where the static type of `a` is `A`. If during the symbolic execution, the dynamic type of the variable `a` is `B` where `B <: A`, then we create on-demand a copy `foo(B)` of `foo(A)` where all the uses of the typed parameter `a` are replaced with a parameter of type `B`. Especially, if `foo` contains virtual call, say `get` where `a` is the receiver, then the call gets redirected to the overridden method in `B`, which simulates the runtime behavior of Java.
This lazy dynamic dispatch mode is only turn on for the tracing mode for now in order to avoid conflicts with sblackshear's approach for sound dynamic dispatch.
Reviewed By: sblackshear
Differential Revision: D2888922
fb-gh-sync-id: 3250c9e
shipit-source-id: 3250c9e
Summary:public
Deprecate the incremental mode.
Several parts of the back-end can be removed.
The options for incremental analysis -i at the python level are now deprecated, and re-routed to --reactive.
The main difference with --reactive is that it does not produce an analysis of the whole project, but is limited to what is reachable via reactive propagation starting from the changed files.
Reviewed By: sblackshear
Differential Revision: D2960078
fb-gh-sync-id: 6e8b46b
shipit-source-id: 6e8b46b
Summary:public
An observer object that registered to a notification center needs to be
unregistered before it is deallocated.
If not, the notification center may send a notification to a gost object.
This diff introduce a checker for this problem.
Reviewed By: dulmarod
Differential Revision: D2949692
fb-gh-sync-id: 1653cec
shipit-source-id: 1653cec
Summary:public
Add extra dereference when accessing fields that have T& type. It is similar
to what is done when accessing variables of T& type.
The only difference is that we need to handle constructor initializer list
separately (this is the only place where the field can be initialized)
Reviewed By: ddino
Differential Revision: D2965887
fb-gh-sync-id: 1b8708b
shipit-source-id: 1b8708b
Summary:public
This just simplifies the end-to-end tests for Dividde By Zero to make the debugging easier when this test fails.
Reviewed By: cristianoc
Differential Revision: D2966296
fb-gh-sync-id: 5eaa1b5
shipit-source-id: 5eaa1b5
Summary:public
Create separate specs for C models compiled in C++. It will allow us to tweak behavior/names of certain
functions based on the compilation language (such as adding `std::` namespace in C++).
Reviewed By: jvillard
Differential Revision: D2938992
fb-gh-sync-id: 73902f8
shipit-source-id: 73902f8
Summary:public
Add to the code to detect violation of the `NoAllocation` annotation. This diff adds the code to detect such issue based on the code of the `PerformanceCritical` checker. In the next diff, I will refine the list of acceptable allocations, like new exceptions, etc, and add the list of corresponding tests.
Reviewed By: sblackshear
Differential Revision: D2938641
fb-gh-sync-id: 9a047dd
shipit-source-id: 9a047dd
Summary:public We model it as the builtin __instanceof which models the instanceof construct of Java.
The behaviour is the same.
Reviewed By: jvillard
Differential Revision: D2938969
fb-gh-sync-id: 2258de3
shipit-source-id: 2258de3
Summary:public
Translate headers every time they are included provided that they are located inside project_root directory.
While this is suboptimal (we might end up translating same header many times), doing it exactly once
is hard due to parallel compilation and template instantiations
Reviewed By: dulmarod
Differential Revision: D2916799
fb-gh-sync-id: 93b72c4
shipit-source-id: 93b72c4
Summary:public
Is seems that automatically inheriting annotations like `PerformanceCritical` or `NoAllocation` is the right thing to do in general. Otherwise, we need to enforce sub-typing rules which in the best case just adds a little bit of documentation, but could miss important issues when the code is not fully annotated. I am simplifying this part to avoid adding boilerplate code for the `NoAllocation` case.
Reviewed By: sblackshear
Differential Revision: D2938627
fb-gh-sync-id: ddb668b
shipit-source-id: ddb668b
Summary:
public
Avoid problems of overwriting good type information with incomplete information
when type declaration happens after its complete definition.
The solution is that we will only time we *update* type information is
when struct declaration has definition as well (which should happen once)
Reviewed By: cristianoc, sblackshear
Differential Revision: D2921811
fb-gh-sync-id: 16baba3
shipit-source-id: 16baba3
Summary:
public
The inductive list predicate was not firing during abstraction because of a type mismatch between C and Java. In Java, the second parameter of the `Sil.Sizeof` constructor is always `Sil.Subtype.exact` in C but is `Sil.Subtype.subtypes` in Java. This diff fixes the confution by comparing the `Sil` types only instead of the type expressions.
Reviewed By: jberdine
Differential Revision: D2912493
fb-gh-sync-id: 3f712a8
shipit-source-id: 3f712a8
Summary:
public
1. Add support for temporary C++ objects.
2. Make constructor calls return constructed objects - it allows us pass them as parameters to another constructs (such as parameters, member expressions etc.)
3. Translate FunctionalCastExpr which sometimes is used instead of CXXTemporaryObjectExpr
Reviewed By: dulmarod
Differential Revision: D2874916
fb-gh-sync-id: d9ac2cc