Summary:
Our model of unique_ptr and shared_ptr relied on the fact that we could C-style cast a pointer to the internal pointer type used in the smart pointer.
This is wrong when the smart pointer is used with a custom deleter that declares its own pointer type whose is not constructible from just a single pointer.
Reviewed By: dulmarod
Differential Revision: D6496203
fbshipit-source-id: 1305137
Summary:
We would previously skip any function that had one of these.
A no-op translation is sufficient to fix this issue (see new E2E test).
Reviewed By: mbouaziz
Differential Revision: D6317323
fbshipit-source-id: 0855bd8
Summary: This check is deprecated and will be replaced by a dedicated checker to detect unitialized values.
Reviewed By: mbouaziz
Differential Revision: D6133108
fbshipit-source-id: 1c0e9ac
Summary:
Attempting to translate these will not go well as the declaration still depends
on some template arguments. Added a test that was previously crashing the
frontend.
Also extend the catching of "Unimplemented" and other errors to `translate_one_decl` as it was useful to debug this issue. In particular, reraise all exceptions and log some additional context when doing so.
update-submodule: facebook-clang-plugins
Reviewed By: mbouaziz
Differential Revision: D5976357
fbshipit-source-id: fca8e38
Summary:
This diff does two things:
# Infer no longer add the contrains that the return value of a skip function is never null. This was leading to false negatives and is not necessary as those return value are treated angelically
# Infer now support `Nonnull` on the return value of skip functions.
Reviewed By: jberdine, sblackshear
Differential Revision: D5840324
fbshipit-source-id: bbd8d82
Summary: Will then be easier to understand if some changes in the test results is legit or not.
Reviewed By: sblackshear
Differential Revision: D5863961
fbshipit-source-id: 7eb3f33
Summary:
We need to make sure that destructors of virtual base classes are called only once. Similarly to what clang does, we have two destructors for a class: a destructor wrapper and an inner destructor.
Destructor wrapper is called from outside, i.e., when variables go out of scope or when destructors of fields are being called.
Destructor wrappers have calls to inner destructors of all virtual base classes in the inheritance as their bodies.
Inner destructors have destructor bodies and calls to destructor wrappers of fields and inner destructors of non-virtual base classes.
Reviewed By: dulmarod
Differential Revision: D5834555
fbshipit-source-id: 51db238
Summary:
The "placement new" operator `new (e) T` constructs a `T` in the pre-allocated memory address `e`.
We weren't translating the `e` part, which was leading to false positives in the dead store analysis.
Reviewed By: dulmarod
Differential Revision: D5814191
fbshipit-source-id: 05c6fa9
Summary:
Simple instance of the problem: analyzing the following program times out.
```
#include <tuple>
void foo() {
std::tuple<std::tuple<int>> x;
}
```
Replacing `std::tuple<std::tuple<int>>` by `std::tuple<int>` makes the analysis
terminate.
In the AST, both tuple<tuple<int>> and tuple<int> have the same template
specialization type: "Pack" (which means we're supposed to go look into the
arguments of the template to get their values). This is not information enough
and that's the plugin fault.
On the backend side, this means that two types have the same Typ.Name.t, namely
"std::tuple<_>", so they collide in the tenv. The definition of
tuple<tuple<int>> is the one making it into the tenv. One of the fields of the
corresponding CxxRecord is of type "tuple<int>", which we see as the same
"tuple<_>", which causes the loop.
update-submodule: facebook-clang-plugins
Reviewed By: mbouaziz
Differential Revision: D5775840
fbshipit-source-id: 0528604
Summary:
Not translating these properly was causing false positives for the dead store analysis in cases like
```
int i = 0;
return [j = i]() { return j; }();
```
Reviewed By: da319
Differential Revision: D5731562
fbshipit-source-id: ae79ac8
Summary: This makes the traces more readable when involving skipped functions.
Reviewed By: sblackshear
Differential Revision: D5731683
fbshipit-source-id: 49d363b
Summary:
With current model, there are issues with cxx range loop. It looks like
it comes from std::vector::size model.
example of such FP:
```
int t = vec.size();
for(auto& elem : vec) {
auto x = elem
}
```
Reviewed By: jvillard
Differential Revision: D5545914
fbshipit-source-id: fbe55b3
Summary: Those are not particularly relevant for the biabduction analysis. It would be easy to have a dedicated checker for this if we happen to need one day.
Reviewed By: sblackshear
Differential Revision: D5530834
fbshipit-source-id: 316e60f
Summary:
update-submodule: facebook-clang-plugins
Moving to a newer version of clang, see ffb5dd0114
Reviewed By: jvillard
Differential Revision: D5452529
fbshipit-source-id: 28bc215
Summary:
We keep track of both `beginPtr` and `endPtr` but the modelling was mostly
about `beginPtr` as some sort of approximation I guess. This shouldn't change
much but will be useful later when doing more iterator stuff.
Reviewed By: mbouaziz
Differential Revision: D5255772
fbshipit-source-id: 0f6e3e8
Summary:
:
There are throw wrapper functions like `std::__throw_bad_alloc()` defined in both libstdc++ (https://github.com/gcc-mirror/gcc/blob/master/libstdc%2B%2B-v3/include/bits/functexcept.h) and libc++ (e.g. 907c1196a7/include/new (L145)). Folly actually exports some of them as well (diffusion/FBS/browse/master/fbcode/folly/portability/BitsFunctexcept.h). The function body of those wrappers merely throws the corresponding exception. My understanding is that the primary purpose of the wrappers is to throw the exception if everything goes well and to fall back to something reasonable when exception is disabled (e.g. when `-fno-exceptions` is passed to the compiler).
The problem is that infer doesn't really understand what those functions do, and I've seen some false positives get reported as a result of it. So to remove those FPs we need to either model them or handle them specially. Modeling those wrappers by either whitelisting them or overriding the include files turns out to be difficult, as those wrappers are only declared but not defined in the STL headers. Their implementations are not available to Infer so whitelisting them does nothing, and if I provide custom implementations in the headers then normal compilation process will be disrupted because the linker would complain about duplicated implementation.
What I did here is to replace functions whose name matches one of the throw wrapper's name with a `BuiltinDecls.exit`. I have to admit that this is a bit hacky: initially I was trying to do something more general: replacing functions with `noreturn` attribute with `BuitinDecls.exit`. That did not work because, CMIIW, the current frontend only exports function attributes for functions with actual bodies, not declaration-only functions. I'd love to be informed if there are better ways to handle those wrappers.
Reviewed By: jeremydubreil
Differential Revision: D5266030
fbshipit-source-id: 4580227
Summary: The flakiness is exercised by upgrading the OCaml compiler to 4.04.0.
Reviewed By: jberdine
Differential Revision: D4859904
fbshipit-source-id: 0dd7ff6
Summary:
Make it possible to write one model which will be used by all template instantiations.
There is one big missing piece: infer never tries to do template instantiation by itself. With current code, it's possible to use generic models
as long as header contains `__infer_generic_model` annotation (see the test as an example).
This is not viable to modify all headers with this annotation hence infer will try to do template instantiation for generic models in later diffs.
Reviewed By: jberdine
Differential Revision: D4826365
fbshipit-source-id: 2233e42
Summary: `__attribute__((annotate("")))` is better way of passing information to the frontend
Reviewed By: jberdine
Differential Revision: D4818805
fbshipit-source-id: 6e8add2
Summary:
Adds a new type and branching for a missing path of execution.
closes#575
Reviewed By: jvillard
Differential Revision: D4738681
fbshipit-source-id: f72344c
Summary:
This issue was spotted in the wild. There may be more of those, unfortunately it's hard to predict
More general problem is that types in infer frontend diverge from clang's types for DerivedToBase cast.
Then, infer uses types from clang anyway and that confuses backend. Getting it always right is very hard
Reviewed By: jvillard
Differential Revision: D4754081
fbshipit-source-id: 5fb7069
Summary:
Updated version of the plugin exports some missing `VarDecls`. To make sure it doesn't break again,
add a test that didn't work before.
Reviewed By: dulmarod
Differential Revision: D4674123
fbshipit-source-id: 0c1677a
Summary:
Infer used to report null dereference when field was accessed later:
```
vector<int> v;
int& a = v[0]; // should be EMPTY_VECTOR_ACCESS here, but it wasn't reported
int b = a; // was NULL_DEREFERENCE here
```
To avoid this problem, model all accesses to vector as dereference of its internal `beginPtr` field.
Reviewed By: jberdine
Differential Revision: D4481942
fbshipit-source-id: 2142894
Summary: Access to std::vector shouldn't be treated as SKIP. Implementation is simple enough to use one from std:: headers
Reviewed By: jvillard
Differential Revision: D4339577
fbshipit-source-id: d1fbbee
Mehdi Bouaziz
Sam Blackshear
Jeremy Dubreil
Jules Villard
Daiva Naudziuniene
Jia Chen
Andrzej Kotulski
Martino Luca
Paco Estevez Garcia