Summary:
We supported globals as sources before, but we did so by allowing ClangTrace etc. to match against any access path in the footprint of the trace.
This is very powerful/flexible, but it's ultimately not a good idea because it leads to traces that are hard to read.
This is because a footprint source doesn't have any information about its provenance: we might know that the value came from a global, but we don't know where the read occurred.
The mechanism for handling procedure calls as sources already knows how to solve this problem.
This diff implements globals as sources as a special case of procedure call sources instead.
This will give us much nicer traces with full provenance of the read from the global.
Reviewed By: mbouaziz
Differential Revision: D5772299
fbshipit-source-id: 491ae81
Summary:
When a lambda has an `auto` parameter, the inferred type of the parameter because part of the name.
Our heuristic for identifying lambda was checking if the lambda's name was exactly `operator()`, which won't catch this case.
Reviewed By: jvillard
Differential Revision: D5753323
fbshipit-source-id: 85ff75a
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: We inject destructor calls of base classes inside destructor bodies after the destructor calls of fields.
Reviewed By: dulmarod
Differential Revision: D5745499
fbshipit-source-id: 90745ec
Summary: We used to crash whenever we hit these. The simple translation implemented here is not particularly inspiring, but it is better than crashing.
Reviewed By: jvillard
Differential Revision: D5702095
fbshipit-source-id: 3795d43
Summary: This makes the traces more readable when involving skipped functions.
Reviewed By: sblackshear
Differential Revision: D5731683
fbshipit-source-id: 49d363b
Summary:
In looking at summaries that Quandary took a long time to compute, one thing I notice frequently is redundancy in the footprint sources (e.g., I might see `Footprint(x), Footprint(x.f), Footprint(x*)`).
`sudo perf top` indicates that joining big sets of sources is a major performance bottleneck, and a large number of footprint sources is surely a big part of this (since we expect the number of non-footprint sources to be small).
This diff addresses the redundancy issue by using a more complex representation for a set of sources. The "known" sources are still in a set, but the footprint sources are now represented as a set of access paths (via an access trie).
The access path trie is a minimal representation of a set of access paths, so it would represent the example above as a simple `x*`.
This should make join/widen/<= faster and improve performance
Reviewed By: jberdine
Differential Revision: D5663980
fbshipit-source-id: 9fb66f8
Summary:
The previous widening operator added stars to the *end* of paths that existed in `next` but not `prev`. This is not enough to ensure termination in the case where the trie is growing both deeper and wider at the same time.
The newly added test demonstrates this issue. In the code, there's an ever-growing path of the form `tmp.prev.next.prev.next...` that wasn't summarized by the previous widening operator. The new widening is much more aggressive: it replaces *any* node present in `next` but not `prev` with a `*` (rather than trying to tack a star onto the end). This fixes the issue.
This issue was causing divergence on tricky doubly-linked list code in prod.
Reviewed By: jeremydubreil
Differential Revision: D5665719
fbshipit-source-id: 1310a92
Summary:
This makes it easier to test a single checker.
Also refactor the code to make it harder to mess up the list of default/all checkers.
Reviewed By: sblackshear
Differential Revision: D5583209
fbshipit-source-id: 7c919b2
Summary:
Previous version was hard to understand because it was doing many things within same code. New version has different code for Arrays, Structs and others.
There is some copy-paste, but it's easier to follow code (open to suggestions though)
Reviewed By: dulmarod
Differential Revision: D5547999
fbshipit-source-id: 77ecb24
Summary: It wasn't using code from `std::vector::empty` which recently was improved. Instead of inlining `std::vector::empty`, call it to know whether vector is empty or not.
Reviewed By: jvillard
Differential Revision: D5573379
fbshipit-source-id: e024a42
Summary: Useful for identifying user-controlled array accesses that could lead to buffer overflows
Reviewed By: mbouaziz
Differential Revision: D5520985
fbshipit-source-id: 92984f6
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:
Bumps facebook-clang-plugins to a version that outputs sizeof() info in bytes and not bits.
update-submodule: facebook-clang-plugins
Reviewed By: akotulski
Differential Revision: D5526747
fbshipit-source-id: 6019542
Summary: The `--failures-allowed` was doing for the Clang frontend what `--keep-doing` was doing for the backend. This revision merges the two options to simplify the Infer CLI and our tests.
Reviewed By: jvillard
Differential Revision: D5474347
fbshipit-source-id: 09bcea4
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:
Pretty basic: warn when we see an assignment instruction `x = ...` and `x` is not live in the post of the instruction.
Only enabled for Clang at the moment because linters already warn on this for Java. But we can enable it later if we want to (should be fully generic).
Reviewed By: jeremydubreil
Differential Revision: D5450439
fbshipit-source-id: 693514c
Summary:
This commit avoids precision loss on pruning.
// x -> [s$1, s$2]
if(x) { ... }
// x -> ?
before: x -> [min(0, s$1), max(0, s$2)]
because two x values, [0, 0] (true case) and [s$1, s$2] (false case), were joined after the if branch.
after: x -> [s$1, s$2]
Reviewed By: mbouaziz
Differential Revision: D5431009
fbshipit-source-id: 14a9efe
Summary:
Problem: The analyzer did not know that the value of `v.size()` is an alias of `v.infer_size`, so `v.infer_size` is not pruned by the if condition. As a result it raises a false alarm.
void safe_access(std::vector<int> v) {
if (v.size() >= 10) {
v[9] = 1; // error: BUFFER_OVERRUN Offset: [9, 9] Size: [5, 5]
}
}
void call_safe_access_Good() {
std::vector<int> v(5, 0);
safe_access(v);
}
Solution: Adding alias for return value to the abstract domain.
Now Inferbo can prune `v.infer_size` because it knows that the value of `v.size()` is an alias of `v.infer_size`. There is already an alias domain in Inferbo, so we added a specific room for the retrun value.
Reviewed By: jvillard, mbouaziz
Differential Revision: D5396988
fbshipit-source-id: 4a4702c
Summary:
:
because otherwise people would believe they can use the internal representation of these std lib but it fails for our models.
Reviewed By: jvillard
Differential Revision: D5368671
fbshipit-source-id: 4e53d5a