Summary:
This diff tries to achieve the followings: if we have the following C++ codes:
```
bool foo(int x, int y) {
return &x == &y;
}
```
We want the C++ frontend to emit Sil as if the input is written as
```
bool foo(int x, int y) {
if (&x == &y) return 1; else return 0;
}
```
This matches the behavior of our Java frontend.
The reason why we prefer an explicit branch is that it will force the backend to eagerly produce two different specs for `foo`. Without the explicit branch, for the above example the backend would produce one spec with `return = (&x == &y)` as the post condition, which is not ideal because (1) we don't want local variables to escape to the function summary, and (2) with the knowledge that no two local variables may alias each other, the backend could actually determines that `&x == &y` is always false, emitting a more precise postcondition `return = 0`. This is not possible if we do not eagerly resolve the comparison expression.
Reviewed By: akotulski
Differential Revision: D5260745
fbshipit-source-id: 6bbbf99
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: We had a model for `Pools.SimplePool`, but were missing models for `Pools.Pool`. Since `SimplePool` and `SynchronizedPool` both extend `Pool`, modeling it should cover all of the cases.
Reviewed By: ngorogiannis
Differential Revision: D5236280
fbshipit-source-id: 9bbdb25
Summary:
:
No longer use deprecated reporting function for the suggest nullable checker
Depends on D5205009
Reviewed By: grievejia
Differential Revision: D5205843
fbshipit-source-id: f6dd059
Summary:
Read/write race errors should always show one trace for a read and one trace for a write.
We forget to pass the conflicting writes to the reporting function in one case, which prevented us from showing a well-formed trace.
Fixed it by making the `conflicts` parameter non-optional
Reviewed By: jberdine
Differential Revision: D5209332
fbshipit-source-id: 05da01a
Summary: We were almost always using `~report_reachable:true`, and in the cases where we weren't it is fine to do so. In general, a sink could read any state from its parameters, so it makes sense to complain if anything reachable from them is tainted.
Reviewed By: mbouaziz
Differential Revision: D5169067
fbshipit-source-id: ea7d659