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
Summary: Our C++ model magic didn't work when instantiating smart pointers with volatile types. Fix it
Reviewed By: jvillard
Differential Revision: D4313271
fbshipit-source-id: 55ffb98
Summary:
Dealing with symbolic links in project root is tricky. To avoid it, always normalize all paths to sources with `realpath`.
Changes to tests are expected - infer started to resolve symbolic links which screws up with our testing mechanism.
Reviewed By: jberdine
Differential Revision: D4237587
fbshipit-source-id: fe1cb01
Summary:
Run all clang tests with project-root at `infer/tests`. I need it because we'll start resolving symbolic links
soon and some tests would lead outside of project root which means we'd start seeing absolute paths in recorded tests.
Diff that does same thing for java tests: D4233236
Reviewed By: jberdine
Differential Revision: D4233194
fbshipit-source-id: c261a2b
Summary:
Record an abstraction of the bug traces in the tests. The abstraction of a
trace is the sequence of descriptions. In practice, descriptions are either
empty, or of the form "start/end/return from/call to procedure X". They seem
pretty stable.
Motivation: there is nothing testing the traces reported by Infer right now,
even though they are surfaced to developers. For instance, Quandary uses
--issues-txt instead of --issues-tests to make sure the traces do not regress.
This change would make this approach more widespread.
Reviewed By: sblackshear
Differential Revision: D4159597
fbshipit-source-id: 9c83952
Summary:
Instead of the custom filtering done by `InferPrint --issues-tests`, use the
filtering done by `infer` and run without filtering for our e2e tests. We still
test the filtering for our build systems integration tests, and this diff
restores that behaviour for the ant test (hence the bugs removed from
ant/issues.exp).
Also add internal exceptions to most tests to get more signal out of them (eg,
knowing when we add assertion failures and the like).
Retire the old `--issues-tests` to limit the number of ways we do filtering.
Reviewed By: jeremydubreil
Differential Revision: D4131308
fbshipit-source-id: 35805cc
Daiva Naudziuniene
Sam Blackshear
Jules Villard
Jeremy Dubreil
Jia Chen
Andrzej Kotulski
Martino Luca
Mehdi Bouaziz
Paco Estevez Garcia
Dulma Churchill
Cristiano Calcagno