Summary:
This diff updates the reachability conditions of proof obligations at every function calls.
Depends on D13781124
Reviewed By: mbouaziz
Differential Revision: D13781147
fbshipit-source-id: 3c8768bd9
Summary:
It adds a semantics for evaluation of abstract location of literal
string, which was missing.
Reviewed By: mbouaziz
Differential Revision: D13915265
fbshipit-source-id: 741df843b
Summary:
This diff does not copy callee's parameters on instantiating abstract
memories at call sites. Before this diff, it copied all reachable
values from callee's parameters including the parameters themselves.
However, they are local variables of callees and should not be copied
to callers.
Reviewed By: mbouaziz
Differential Revision: D13877370
fbshipit-source-id: d70c2c317
Summary: We do not want to export unnecessary information from clang plugin, hence, the solution to this false positive would be to annotate with `__unused__` attribute.
Reviewed By: jvillard
Differential Revision: D13861333
fbshipit-source-id: 774009f37
Summary:
This will allow to get the numerical results for Cost, Hoisting, Purity without the Inferbo issues.
For now, I still forced Inferbo issues for Cost and Purity to avoid lots of changes in tests, that will go away soon.
Reviewed By: ezgicicek, skcho
Differential Revision: D13826741
fbshipit-source-id: 796d1a50d
Summary: The goal of this diff is to avoid using reporting (which as side-effects on the reportlog) during the checking pass, and only report everything at the end.
Reviewed By: skcho
Differential Revision: D13825520
fbshipit-source-id: ed2217c11
Summary:
The `oenv` is an option.
This diff ensures that it is `Some` during the analysis and `None` when it is stored in a summary.
It could have been resolved with another type, e.g. `unit`, but an option was needed to avoid duplicating code that is generic up to some point.
The price to pay is a parametric type.
Reviewed By: skcho
Differential Revision: D13825418
fbshipit-source-id: 71824609d
Summary:
In some rare cases, the CFG is broken, the analysis cannot reach the exit node and we won't update the summary for this procedure.
In this diff, the summary is gonna be updated with `Bottom` instead.
Reviewed By: skcho
Differential Revision: D13801731
fbshipit-source-id: 79d412429
Summary:
This diff extends the abstract domain to keep binary conditions on
prunings, so Inferbo can suppress more proof obligations (i.e., false
positives) that are known to be unreachable according to the binary
conditions.
Depends on D13729600
Reviewed By: mbouaziz
Differential Revision: D13749914
fbshipit-source-id: 314f048f1
Summary:
This will allow disjunctive analyzers to return sets of states as a
result instead of always returning one state. More precisely, this will
be needed for pulse when it becomes inter-procedural, if we take
summaries of functions to be disjunctive too (like, e.g., biabduction
does with several specs per function).
Reviewed By: mbouaziz
Differential Revision: D13537601
fbshipit-source-id: f54caf802
Summary:
Printing "N specs" next to function definitions in the HTML debug is
misleading because there are more checkers than just biabduction.
Reviewed By: mbouaziz
Differential Revision: D13572456
fbshipit-source-id: 209b874df
Summary:
`memcpy` should copy the contents of the source to the destination.
Depends on D13634754
Reviewed By: ezgicicek, mbouaziz
Differential Revision: D13668414
fbshipit-source-id: cb0ff2010
Summary: It extends the abstract location for C string length, i.e., the first index of the null character in character array.
Reviewed By: mbouaziz
Differential Revision: D13634241
fbshipit-source-id: d2727d5f5
Summary: Publish solutions to the lab, and a Docker file and image to get started more quickly with infer hacking.
Reviewed By: mbouaziz
Differential Revision: D13648847
fbshipit-source-id: daf48ad03
Summary:
This diff prevents deduplications of issues when they have different
conditions to reach.
Reviewed By: mbouaziz
Differential Revision: D13596220
fbshipit-source-id: 95f802edb
Summary:
In ObjC there are no access modifiers. The strongest alternative is to put methods in the implementation but omit them from the interface declaration.
Put exported ObjC methods in their own field in the class structure and use that in RacerD to decide whether to report on the method.
Reviewed By: mbouaziz
Differential Revision: D13597504
fbshipit-source-id: c4a3d2705
Summary:
It suppresses intended integer overflows that generate hash values or random numbers. For judging that the intention of integer overflow, it applies a heuristics: checking if traces of issues include a whitelisted words, e.g., "rand" or "seed".
While we would be able to suppress all integer overflows of unsigned integers since they have defined behaviors, we don't want to miss unintended integer overflows, e.g., that on unsigned index value.
Depends on D13595958
Reviewed By: mbouaziz
Differential Revision: D13595967
fbshipit-source-id: 8d3aca5a7
Summary:
- `Printer.NodesHtml.start_node` prints the instructions rather than doing it in the callee
- use color class for `<LISTING>` rather than wrapping them in `<span>` (also fixes a wrong nesting between `<LISTING>` and `<span>`)
- `Summary.pp_html` is always `Black`
- New line before `<hr>` and `<LISTING>`
- `Io_infer.Html.create` takes a `SourceFile.t` rather than a `path_kind`
- typo
Reviewed By: jvillard
Differential Revision: D13572247
fbshipit-source-id: 65f57df25
Summary:
Split into:
- `PulseDiagnostic`, formerly `PulseDomain.Diagnostic`
- `PulseOperations`, formerly `PulseDomain.Operations`
This breaks down the now quite large and complex PulseDomain.ml into
more manageable pieces. More importantly, it will allow us to build a
bigger pulse domain later, where elements of the domain are pairs of the
base domain that include a biabductive "footprint".
What's not as nice is that more of the interface of `PulseDomain` is
exposed, in particular `PulseDomain.Memory` and `PulseDomain.Stack`.
We'll have to be careful not to break abstraction barriers and prefer
`PulseOperations` to `PulseDomain` outside of the domain implementation.
OCaml forces us to do that because of the multi-file approach. It could
be solved by introducing pulse domains as a library but who has time for
that...
Sending early because rebasing that diff is painful.
Reviewed By: ngorogiannis
Differential Revision: D13537602
fbshipit-source-id: d211d6e84
Summary:
Record per-location traces. Actually, that doesn't quite make sense as a
location can be accessed in many ways, so associate a trace to each
*edge* in the memory graph. For instance, when doing `x->f = *y`, we
want to take the history of the `<val of y> --*--> ..` edge, add "assigned
at location blah" to it and store this extended history to the edge
`<val of x> --f--> ..`.
Use this machinery to print nicer traces in `infer explore` and better
error messages too (include the last assignment, like biabduction
messages).
Reviewed By: da319
Differential Revision: D13518668
fbshipit-source-id: 0a62fb55f
Summary:
This diff substitutes the conditions of proof obligations strictly, so that the condition of "p!=Null" becomes bottom
when callee's p is Null.
In the non-strict substitution (which is used by default), if p's location is not found it returns the unknown location.
On the other hand, in the strict substitution (which is used only in the substitution of condition of proof obligation),
it returns bottom location.
Depends on D13415366, D13414636
Reviewed By: mbouaziz, jvillard
Differential Revision: D13415377
fbshipit-source-id: 5ae1e888e
Summary: This diff unset powloc and arrayblk values of p when assume(p==Null).
Reviewed By: mbouaziz, jvillard
Differential Revision: D13415366
fbshipit-source-id: a491a957f
Summary:
For abstract values representing one concrete value, create only one symbol instead of two.
Still create two symbols (lb, ub) for abstract values representing multiple concrete values (like array cells).
As a consequence, comparisons of symbolic values are more precise (we can even prove equality). I expect to remove a bunch of FPs.
Another consequence is the disappearance of `.lb` and `.ub` in many reports.
Reviewed By: skcho
Differential Revision: D13072084
fbshipit-source-id: 9bc0b9881
Summary: In the `operator=` case that assigns from a temporary, we want to assign an object of a temporary not it's address (as a comment already says)
Reviewed By: jvillard
Differential Revision: D13518496
fbshipit-source-id: 72bd23623
Summary: Adding a test case for use after destructor for temporaries. At the moment pulse does not find it as frontend does not inject destructors for temporaries.
Reviewed By: jvillard
Differential Revision: D13506229
fbshipit-source-id: 31b9466f7
Summary:
It weakens canonical path in order to avoid an explosion of locations when a struct type has pointers to struct.
For example:
```
struct Tree {
struct Tree *root;
struct Tree *left;
struct Tree *right;
};
```
It was able to generate lots of abstract locations before this diff:
```
t->root
t->left
t->right
t->root->left
t->root->right
t->left->root
t->left->right
t->right->root
t->right->left
t->root->left->right
t->root->right->left
t->left->root->right
t->left->right->root
t->right->root->left
t->right->left->root
```
By this diff, pointer fields that have the same type are (unsoundly) canonicalized to the same one. For example,
```
t->root
t->root->left
t->root->right
t->root->left->right
t->root->right->left
```
are canonicalized to `t->root`. This is definitely unsound but I believe it is better than the location explosion by which analyses do not terminate in a reasonable time or giving a fixed limit of depth to the field access.
Reviewed By: mbouaziz
Differential Revision: D13503808
fbshipit-source-id: 867018712
Summary:
When a C++ temporary goes out of scope, tag its address in the heap with
a new attribute `AddressOfCppTemporary` so that we can later check that
we don't return it.
Reviewed By: da319
Differential Revision: D13466898
fbshipit-source-id: 8808338b4
Summary:
When assign to the special `return` variable, check that the result is
not the address of a local variable, otherwise report.
Reviewed By: ngorogiannis
Differential Revision: D13466896
fbshipit-source-id: 465da7f13
Summary: Naming it `FP_` was a mistake in the original commit that copied the tests over as pulse has never reported on that method.
Reviewed By: da319
Differential Revision: D13465324
fbshipit-source-id: f8b24ebda
Summary:
In order to avoid FPs due to lack of relational info, we apply a heuristic: proof obligations has a latest pruned values,
then it is instantiated at Call statements. If there is a bottom value in the instantiated pruned values, we can say the
program point where the proof obligation is introduced is unreachable with the given parameters of the function.
Depends on D13414441
Reviewed By: mbouaziz
Differential Revision: D13414483
fbshipit-source-id: 61bd34ebb
Summary:
It's ok to take an address of a field / array access of an invalid object.
This diff calculates the inner most dereference for an access expression starting with `&` and does not report on the dereference even if the address is invalid.
Reviewed By: jvillard
Differential Revision: D13450758
fbshipit-source-id: 18c038701
Summary:
When we create Dereference edge, we also create TakeAddress back edge. This causes false positives for stack variables. When we write to a stack variable and then take its address, the resulting address is the one from the back edge of the written value. See example `push_back_value_ok`. To solve this issue, this diff changes stack to denote a map from address of variables rather than from variables.
We still have issue for fields, see example, FP_push_back_value_field_ok. To solve this, we probably need to remove back edges.
Reviewed By: jvillard
Differential Revision: D13432415
fbshipit-source-id: 9254a1a6d
Summary: Mostly a revert of D13190876 once the disjunctive domain is in place.
Reviewed By: da319
Differential Revision: D13432488
fbshipit-source-id: f1e98ef0d
Summary:
Change join/widen policies to more interesting ones and play around to
find a good tradeoff.
Reviewed By: mbouaziz
Differential Revision: D13432492
fbshipit-source-id: 2c3e498dd
Summary:
Introduce machinery to do disjunctive HIL domains and use it for pulse,
but only in a mode that preserves the existing behaviour.
The disjunctive domain is a functor that turns any (HIL for now)
transfer function module into one operating on sets of elements of the
original domain. The behaviour of joins (and widenings, which are equal
to joins) can be chosen when instantiating the functor among 3
behaviours:
- `` `JoinAfter n`: when the set of disjuncts gets bigger than `n` the
underlying domain's join is called to collapse them into one state
- `` `UnderApproximateAfter n`: when the sest of disjuncts gets bigger
than `n` then just stop adding new states to it, drop any further states
on the floor. This corresponds to an under-approximation/bounded
approach.
- `` `NeverJoin`
The widening is always of the form ``
`UnderApproximateAfterNumIterations max_iter` for now since the only
user is pulse and I'm not sure what else would be useful.
Picking `` `JoinAfter 0` gives the same results as the non-disjunctive
domain since the underlying `join` will always be called. Make pulse use
this mode for now, and tune it in a next diff.
Reviewed By: mbouaziz
Differential Revision: D13431375
fbshipit-source-id: b93aa50e7
Summary:
This will be useful to make the analysis more precise. In particular, it
allows a disjunctive version of pulse to deal will deleting vector
elements in a loop: without this, deleting an array element in one
iteration will make the analysis think that the next array element is
invalid too since they are all the same. By keep track of the index, we
can detect when we are sure that two elements are the same and only
report in that case.
Reviewed By: ngorogiannis
Differential Revision: D13431374
fbshipit-source-id: dae82deeb
Summary:
A lot of functors that take a `Make{SIL,HIL}` can take a `{SIL,HIL}`
directly instead. This makes my head hurt a bit less.
Reviewed By: mbouaziz
Differential Revision: D13416967
fbshipit-source-id: eb0b33bc4
Summary:
When a lambda gets created, record the abstract addresses it captures, then
complain if we see some of them be invalidated before it is called.
Add a notion of "allocator" for reporting better messages. The messages are
still a bit sucky, will need to improve them more generally at some point.
```
jul lambda ~ infer 1 infer -g --pulse-only -- clang -std=c++11 -c infer/tests/codetoanalyze/cpp/pulse/closures.cpp
Logs in /home/jul/infer.fb/infer-out/logs
Capturing in make/cc mode...
Found 1 source file to analyze in /home/jul/infer.fb/infer-out
Found 2 issues
infer/tests/codetoanalyze/cpp/pulse/closures.cpp:21: error: USE_AFTER_DESTRUCTOR
`&(f)` accesses address `s` captured by `&(f)` as `s` invalidated by destructor call `S_~S(s)` at line 20, column 3 past its lifetime (debug: 5).
19. f = [&s] { return s.f; };
20. } // destructor for s called here
21. > return f(); // s used here
22. }
23.
infer/tests/codetoanalyze/cpp/pulse/closures.cpp:30: error: USE_AFTER_DESTRUCTOR
`&(f)` accesses address `s` captured by `&(f)` as `s` invalidated by destructor call `S_~S(s)` at line 29, column 3 past its lifetime (debug: 8).
28. f = [&] { return s.f; };
29. }
30. > return f();
31. }
32.
Summary of the reports
USE_AFTER_DESTRUCTOR: 2
```
Reviewed By: da319
Differential Revision: D13400074
fbshipit-source-id: 3c68ff4ea
Summary: Model more `std::vector` functions that can potentially invalidate references to vector's elements (https://en.cppreference.com/w/cpp/container/vector).
Reviewed By: mbouaziz
Differential Revision: D13399161
fbshipit-source-id: 95cf2cae6
Summary:
Some code calls `this->~Obj()` then proceeds to use fields in the current
object, which previously we would report as invalid uses. Assume people know
what they are doing and ignore destructor calls to `this`.
Reviewed By: mbouaziz
Differential Revision: D13401145
fbshipit-source-id: f6b0fb6ec
Summary:
`AccessExpression.t` represents array accesses as `ArrayOffset of t * Typ.t * t
list`, i.e. the index is represented by a list of access expressions. This is
not precise enough when indices cannot be represented as such. In fact, in
general any `HilExp.t` can be an array index but this type was an approximation
that was good enough for existing checkers based on HIL.
This diff changes the type of access expressions to be parametric in the type
of array offsets, and uses this to record `HilExp.t` into them when translating
from SIL to HIL.
To accomodate the option of not caring about array offsets
(`include_array_indexes=false`), the type of array offsets is an option type.
Reviewed By: mbouaziz
Differential Revision: D13360944
fbshipit-source-id: b01442459
Summary:
`AccessExpression.t` and `HilExp.t` are about to become mutually
recursive, this will help distinguish the actual changes from the moving
of code around.
This deletes the file left around in the previous commit to preserve
callers of `AccessExpression`.
Reviewed By: mbouaziz
Differential Revision: D13377645
fbshipit-source-id: 71338d1f3
Summary:
`AccessExpression.t` and `HilExp.t` are about to become mutually
recursive, this will help distinguish the actual changes from the moving
of code around.
Reviewed By: mbouaziz
Differential Revision: D13377644
fbshipit-source-id: 9d6f290b6
Summary:
This will be useful for proper support of array indexes in pulse and in
HIL in general.
Reviewed By: mbouaziz
Differential Revision: D13377642
fbshipit-source-id: e431121fb
Summary: It weakly updates array when there are more than two contents.
Reviewed By: mbouaziz
Differential Revision: D13318443
fbshipit-source-id: fa740d8b1
Summary:
It materializes symbolic values of function parameters on-demand. The on-demand materialization is triggered when finding a value from an abstract memory and joining/widening abstract memories.
Depends on D13294630
Main idea:
* Symbolic values are on-demand-ly generated by a symbol path and its type
* In order to avoid infinite generation of symbolic values, symbol paths are canonicalized by structure types and field names (which means they are abstracted to the same value). For example, in a linked list, a symbolic value `x->next->next` is canonicalized to `x->next` when the structures (`*x` and `*x->next`) have the same structure type and the same field name (`next`).
Changes from the previous code:
* `Symbol.t` does not include `id` and `pname` for distinguishing symbols. Now, all symbols are compared by `path:SymbolPath.partial` and `bound_end`.
* `SymbolTable` is no longer used, which was used for generating symbolic values with new `id`s.
Reviewed By: mbouaziz
Differential Revision: D13294635
fbshipit-source-id: fa422f084
Summary:
`eval_locs` is like `eval |> get_all_locs` but avoids computing things that aren't necessary.
The goal was not to be an optimization but is needed for Java where array blocks don't have offsets.
Reviewed By: skcho
Differential Revision: D13190939
fbshipit-source-id: 1cc0e6338
Summary: Similarly as `std::vector::push_back`, `std::vector::reserve` can invalidate the references to elements if the new size is bigger than the existing one. More info on `std::vector::reserve`: https://en.cppreference.com/w/cpp/container/vector/reserve
Reviewed By: jvillard
Differential Revision: D13340324
fbshipit-source-id: bf99b6923
Summary: Moving all the files related to nullable type checking under the same directory. The goal is to merge everything into the same backend based on the AI framework and access expressions.
Reviewed By: ngorogiannis
Differential Revision: D13350880
fbshipit-source-id: 8ab3cf81b
Summary: Instead of variable having the value of a single location on stack, we now allow variables to have multiple locations. Consequently, we also allow a memory location to point to a set of locations in the heap. We enforce a limit on a maximum number of locations in a set (currently 5).
Reviewed By: jvillard
Differential Revision: D13190876
fbshipit-source-id: 5cb5ba9a6
Summary:
At function calls, it copies callee's values that are reachable from parameters.
Depends on D13231291
Reviewed By: mbouaziz
Differential Revision: D13231711
fbshipit-source-id: 1e8aed1c4
Summary: It instantiates not only symbols for bound but also symbols for locations at function calls.
Reviewed By: mbouaziz
Differential Revision: D13231291
fbshipit-source-id: ce23a943b
Summary: Recent improvements in join fixed `FP_allocate_in_branch_ok` because the variable was not read after the join.
Reviewed By: mbouaziz
Differential Revision: D13233441
fbshipit-source-id: 89b701e12
Summary:
It adds symbolic locations for paramters, which will be used for fixing instantiations of parameters in the
following diffs.
Reviewed By: mbouaziz, jvillard
Differential Revision: D13214293
fbshipit-source-id: f016ea4c3
Summary: Delete function that would get a linter warning or not depending on the version of Xcode.
Reviewed By: martintrojer
Differential Revision: D13215750
fbshipit-source-id: 886ce397d
Summary: It is not used yet and still manages to cause false positives.
Reviewed By: mbouaziz
Differential Revision: D13102948
fbshipit-source-id: 2122666c2
Summary:
It's useful for checkers to know when variables go out of scope to
perform garbage collection in their domains, especially for complex
domains with non-trivial joins. This makes the analyses more precise at
little cost.
This could have been added as a custom function call to a builtin, but I
decided against it because this instruction doesn't have the semantics
of any function call. It's better for each checker to explicitly not
deal with the custom instruction instead.
Reviewed By: jberdine
Differential Revision: D13102951
fbshipit-source-id: 33be22fab
Summary:
Before, the liveness pre-analysis would place extra instructions in the
CFG for either:
1. marking an `Ident.t` as dead, or
2. marking a `Pvar.t` as `= 0`
But we have no way of marking pvars dead without setting them to 0. This
is bad because setting pvars to 0 is not possible everywhere they are
dead. Indeed, we only do it when we haven't seen their address being
taken anyway. This prevents the following situation, recorded in our tests:
```
int address_taken() {
int** x;
int* y;
int i = 7;
y = &i;
x = &y;
// if we don't reason about taken addresses while adding nullify instructions,
// we'll add
// `nullify(y)` here and report a false NPE on the next line
return **x;
}
```
So we want to mark pvars as dead without nullifying them. This diff
extends the `Remove_temps` SIL instruction to accept pvars as well, and
so renames it to `ExitScope`.
Reviewed By: da319
Differential Revision: D13102953
fbshipit-source-id: aa7f03a52
Summary:
Switches from opam 1 to opam 2.
Opam2 has some cool new features that simplify some of the scripting.
Notable changes:
1. Use the new `opam lock` *plugin* from https://github.com/AltGr/opam-lock/ instead of https://github.com/rgrinberg/opam-lock. This has a simpler interface for our purposes.
2. Change the way `./build-infer.sh` can be called to use an already existing switch: simply pass `--user-opam-switch` to the script and it won't attempt to create/set the current switch. This can be used to build infer in a local switch for instance.
3. Take advantage of automatic pinning where possible, eg to install infer deps without using opam.locked.
Reviewed By: ngorogiannis
Differential Revision: D13167863
fbshipit-source-id: 1a667c270
Summary:
It removes the `represents_multiple_values` parameters when we can know them from `path` values.
Depends on D12939124
Reviewed By: skcho
Differential Revision: D12939130
fbshipit-source-id: 30ff768b2
Summary:
It modifies sizes and offsets of array values on pointer castings.
Currently, it supports only simple castings of pointer-to-integers.
Reviewed By: mbouaziz
Differential Revision: D12920589
fbshipit-source-id: a5ba831b8
Summary: In this diff, it passes the parameter of integer type widths to evaluation functions. The parameter which will be used for casting in the following diff.
Reviewed By: mbouaziz
Differential Revision: D12920581
fbshipit-source-id: 48bbc802b
Summary:
It enables the translation of casting expression. As of now, it
translates only the castings of pointers to integer types, in order to
avoid too much of change, which may mess the checkers up.
Reviewed By: jvillard
Differential Revision: D12920568
fbshipit-source-id: a5489df24
Summary:
Useful to understand the changes in the pre-analysis, or to inspect the
CFG that checkers actually get.
This means that the pre-analysis always runs when we output the dotty,
but I don't really see a reason why not. In fact, we could probably
*always* store the CFGs as pre-analysed.
Reviewed By: mbouaziz
Differential Revision: D13102952
fbshipit-source-id: 89f3102ec
Summary: It fixes the conditions of the `check` function to address `is_collection_add` cases correctly.
Reviewed By: mbouaziz
Differential Revision: D13081281
fbshipit-source-id: 39ae5ef03
Summary: Experimental feature: Use memcached for summaries as a look-aside cache during analysis.
Reviewed By: jvillard
Differential Revision: D12939311
fbshipit-source-id: 9f78994e2
Summary:
Currently, if there are several reports on the same line, the most important one is reported together with a message containing how many reports were suppressed.
This is sometimes causing the bug hash we use believe that a report is introduced (eg if the number of suppressed reports changes).
Reviewed By: mbouaziz
Differential Revision: D13067306
fbshipit-source-id: 1cc0c6d3a
Summary:
Messages emitted by cost-analysis now look like the following:
Complexity of this function has **increased** from `O(1)` to `O(n)`.
Reviewed By: mbouaziz
Differential Revision: D13058008
fbshipit-source-id: 119037703
Summary:
Update clang plugin which now gives names to variables captured by lambdas that were empty before.
update-submodule: facebook-clang-plugins
Reviewed By: jvillard
Differential Revision: D12979015
fbshipit-source-id: 0b092fb24
Summary:
It turns out keeping attributes (such as invalidation facts) separate
from the memory is a bad idea and leads to loss of precision and false
positives, as seen in the new test (which previously generated a
report).
Allow me to illustrate on this example, which is a stylised version of
the issue in the added test: previously we'd have:
```
state1 = { x = 1; invalids={} }
state2 = { x = 2; invalids ={1} }
join(state1, state2) = { x = {1, 2}; invalids={{1, 2}} }
```
So even though none of the states said that `x` pointed to an invalid
location, the join state says it does because `1` and `2` have been
glommed together. The fact `x=1` from `state1` and the fact "1 is
invalid" from `state2` conspire together and `x` is now invalid even
though it shouldn't.
Instead, if we record attributes as part of the memory we get that `x`
is still valid after the join:
```
state1 = { x = (1, {}) }
state2 = { x = (2, {}) }
join(state1, state2) = { x = ({1, 2}, {}) }
```
Reviewed By: mbouaziz
Differential Revision: D12958130
fbshipit-source-id: 53dc81cc7
Summary:
I hear that this scheduler is better. I want the best scheduler
possible. Also pulse's join is a bit complex so it might matter one day.
whydididothis
Reviewed By: mbouaziz
Differential Revision: D12958131
fbshipit-source-id: 3bd77ccba
Summary: There is a bug on the instantiation of function parameters.
Reviewed By: mbouaziz
Differential Revision: D12973691
fbshipit-source-id: ca7fbc4e6
Summary: The aligned width of bool should be 1-byte, while the range of bool [0,1].
Reviewed By: jvillard
Differential Revision: D12932394
fbshipit-source-id: be1a5d6d1
Summary: For a general case of `operator=` we want to create a fresh location for the first parameter as `operator=` behaves as copy assignment.
Reviewed By: jvillard
Differential Revision: D12940635
fbshipit-source-id: 89c6e530d
Summary:
Whenever `vec.reserve(n)` is called, remember that the vector is
"reserved". When doing `vec.push_back(x)` on a reserved vector, assume
enough size has been reserved in advance and do not invalidate the
underlying array.
This gets rid of false positives.
Reviewed By: mbouaziz
Differential Revision: D12939837
fbshipit-source-id: ce6354fc5
Summary:
Instead of keeping at most one invalidation fact for each address, keep
a set of them and call them "attributes". Keeping a set of invalidation
facts is redundant since we always only want the smallest one, but
makes the implementation simpler, especially once we add more kinds of
attributes (used for modelling, see next diffs).
Reviewed By: mbouaziz
Differential Revision: D12939839
fbshipit-source-id: 4a54c2132
Summary:
Copied on the ownership checker logic: return the initial value of the
domain as return. This can probably be improved.
Reviewed By: mbouaziz
Differential Revision: D12888102
fbshipit-source-id: 9e2dac7fc
Summary:
When initialising a variable via semi-exotic means, the frontend loses
the information that the variable was initialised. For instance, it
translates:
```
struct Foo { int i; };
...
Foo s = {42};
```
as:
```
s.i := 42
```
This can be confusing for backends that need to know that `s` actually
got initialised, eg pulse.
The solution implemented here is to insert of dummy call to
`__variable_initiazition`:
```
__variable_initialization(&s);
s.i := 42;
```
Then checkers can recognise that this builtin function does what its
name says.
Reviewed By: mbouaziz
Differential Revision: D12887122
fbshipit-source-id: 6e7214438
Summary:
Now that arrays are dealt with separately (see previous diff), we can
turn the join back into an over-approximation as far as invalid
locations are concerned.
Reviewed By: skcho
Differential Revision: D12881989
fbshipit-source-id: fd85e49c0
Summary:
Arrays are the main source of false positives that prevent us from
having a better (less under-approximate) join in general. The next diff
improves join and I split this off to make it easier to review.
Reviewed By: mbouaziz
Differential Revision: D12881986
fbshipit-source-id: 5f52dea27
Summary:
This prevents the join from wrongly assuming that we haven't seen a
variable on one side of the join.
Reviewed By: skcho
Differential Revision: D12881987
fbshipit-source-id: 42a776adb
Summary:
Smaller numbers are easier to read and abstract addresses should never
be shared across functions anyway.
Reviewed By: da319
Differential Revision: D12881988
fbshipit-source-id: f9bcfa343
Summary:
As explained in the added comment, clang started adding `-faddrsig` at the end
of every `-cc1` command, which trumps our heuristic for finding the file name
(thus we would write debug scripts to `-faddrsig.ast.sh`, do filename-based
filtering on `-faddrsig` instead of the source path, and more...). We rely on
the file name being the last argument in `-cc1` commands because so far that's
always been the case, and we don't want to parse the clang command line and
have to know about all the clang options...
Thanks martinoluca for the trick of simply passing `-fno-addrsig`!
Reviewed By: martinoluca
Differential Revision: D12921987
fbshipit-source-id: 28bebe647
Summary:
The upcoming ocamlformat has the ability to parse and format
docstrings. This requires that the docstrings conform to the ocamldoc
spec a bit more strongly. If a docstring does not parse, it is left
alone, but if it is morally ill-formed but parses by chance, it can be
reformatted incorrectly. This patch fixes the existing instances of
this problem.
Reviewed By: mbouaziz
Differential Revision: D12911937
fbshipit-source-id: 1c2eb590b
Summary:
For more deduplications of issues, this diff loosens the condition of
similar bounds. The previous condition of similar bounds was too
strict, so [0,0] and [0,+oo] were not similar.
Depends on D10851762
Reviewed By: mbouaziz
Differential Revision: D10866127
fbshipit-source-id: 4ba912a88
Summary: For `operator=(lhs, rhs)` we want to model it as an assignment if rhs is materialized temporary created in the constructor.
Reviewed By: jvillard
Differential Revision: D10462510
fbshipit-source-id: 998341e69
Summary: Do not create a new location for placement new argument if it already exists.
Reviewed By: jvillard
Differential Revision: D12839942
fbshipit-source-id: 758b67a82
Summary:
In order to know whether a global variable is an integral constant
expression in C, this diff adds a field for the results of isInitICE.
The controller you requested could not be found.: facebook-clang-plugins
Reviewed By: mbouaziz
Differential Revision: D12838521
fbshipit-source-id: 388bff1f3
Summary:
This may help running the id map bookkeeping on its own in the future
and makes the code slightly more readable in my opinion.
Reviewed By: mbouaziz
Differential Revision: D12858066
fbshipit-source-id: fea4aea63
Summary:
HIL wanted to do its own HTML printing, causing code duplication and hacks to
avoid double opening/closing files. Instead, pass a hook to print SIL
instructions or not.
This also makes the debug HTML be printed even in case of raised exceptions,
which is invaluable to debug crashes or even just reports in the case of
checkers that can raise `Stop_analysis` (pulse only for now).
This also print intermediate abstract states between instructions instead of
only at the start and end of nodes, for moar debugging.
Reviewed By: mbouaziz
Differential Revision: D12857425
fbshipit-source-id: 4ee6c88d6
Summary:
Get rid of `USE_AFTER_LIFETIME`. This could be useful to deploy pulse
alongside the ownership checker too.
Reviewed By: da319
Differential Revision: D12857477
fbshipit-source-id: 8e2a2a37c
Summary: Make the whole type private, introduce constructors for each variant, and deal with the consequences.
Reviewed By: da319
Differential Revision: D12825810
fbshipit-source-id: a01922812
Summary:
Keep `USE_AFTER_LIFETIME` for unclassified errors (for now it contains
vector invalidation too because I can't think of a good name for
them, and maybe it makes sense to wait until we have more types of them
to decide on a name).
Reviewed By: da319
Differential Revision: D12825060
fbshipit-source-id: bd75ef698
Summary:
Getting this right will be long and complex so for now the easiest is to
underreport and only consider as invalid the addresses we know to be invalid on
both sides of a join. In fact the condition for an address to be invalid after
a join is more complex than this: it is invalid only if *all* the addresses in
its equivalence class as discovered by the join are invalid.
Reviewed By: skcho
Differential Revision: D12823925
fbshipit-source-id: 2ca109356
Summary: Similarly as for destructors, we provide an address of an object as a first parameter to constructors. When constructor is called we want to create a fresh location for a new object.
Reviewed By: jvillard
Differential Revision: D10868433
fbshipit-source-id: b60f32953
Summary:
There were several lists constructed unnecessarily -- replaced them with find_maps
and hopefully simplified the logic.
Reviewed By: mbouaziz, jvillard
Differential Revision: D12823559
fbshipit-source-id: 1f06b20f3
Summary:
Sometimes in debug mode, the condition set is too big to print in the
log file. This diff limits the maximum number of conditions to print
as 30.
Reviewed By: mbouaziz
Differential Revision: D12836661
fbshipit-source-id: 8ddfe64a7
Summary: We provide an address of an object as a parameter to destructor. When destructor is called the object itself is invalidated, but not the address.
Reviewed By: jvillard
Differential Revision: D12824032
fbshipit-source-id: 516eebcf8
Summary:
Seems useful to know when we're printing one instruction only, but not when we
print lots of them for readability.
Reviewed By: mbouaziz
Differential Revision: D12823481
fbshipit-source-id: 2beb339f2
Summary:
It terminates narrowing when new and old states are not comparable.
Since current narrowing does not use meet operations guaranteeing
termination of narrowing, it tries to terminate narrowing more
conservatively.
Reviewed By: mbouaziz
Differential Revision: D12815419
fbshipit-source-id: e8b45199e
Summary: It tries division on minmax value approximately, rather than just returning infinities. For example, `[0,2+min(6,s)] / 2` returns `[0,4]`.
Reviewed By: mbouaziz
Differential Revision: D10867091
fbshipit-source-id: d3f49987b
Summary:
This diff preserves values of offset and index separately, rather than
one value of their addition, because premature addition results in
imprecise FPs by the limited expressiveness of the domain.
Reviewed By: mbouaziz
Differential Revision: D10851393
fbshipit-source-id: 1685ead36