Summary: Unknown library returns the unknown pointer as well as the top interval.
Reviewed By: mbouaziz, jvillard
Differential Revision: D5282669
fbshipit-source-id: 34c7e18
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:
- model `exit` as `Bottom`
- model `fgetc` as returning `[-1; 255]` rather than `[-1; +oo]`
- reduced the number of model functions for simple models
Reviewed By: KihongHeo
Differential Revision: D5137485
fbshipit-source-id: 943eeeb
Summary:
This diff fixes unintentional bottoms in pointer arithmetic of inferbo.
The pointer arithmetic on addresses of variables (not array) just returns
the operand.
Reviewed By: jvillard
Differential Revision: D5060424
fbshipit-source-id: 495d8b8
Summary:
Previously all knowledge of the dynamic length of such arrays was lost to infer:
```
void foo(int len) {
int a[len];
}
```
The translation of this program would make no reference to `len` (except as a
param of `foo`).
Translate this "initialization" using the existing `__set_array_length` infer
builtin, as:
```
# Declare local a[_]
n$0 = len;
__set_array_length(a, len);
```
update-submodule: facebook-clang-plugins
Reviewed By: mbouaziz
Differential Revision: D4969446
fbshipit-source-id: dff860f
Summary:
This commit fixes a problem that the buffer overrun checker incorrectly
stops when a global variable (bottom) is involved in control flow.
In the new version, abstract memories return Top for unanalyzed abstract
variables.
Reviewed By: mbouaziz
Differential Revision: D5016447
fbshipit-source-id: 5132448
Summary:
An array has a static or dynamic length (number of elements), but it also has a
stride, determined by the type of the element: `sizeof(element_type)`. We don't
have a good `sizeof()` function available on SIL types, so record that stride
in the array type.
update-submodule: facebook-clang-plugins
Reviewed By: mbouaziz
Differential Revision: D4969697
fbshipit-source-id: 98e0670
Summary:
Now,
infer -a infer -- ...
and
infer -a checkers --biabduction -- ...
will return the same list of errors
Reviewed By: sblackshear
Differential Revision: D5023223
fbshipit-source-id: f52ce5d
Summary:
The bufferoverrun checkers can now be run with:
infer -a checkers --bufferoverrun -- ...
Reviewed By: jeremydubreil
Differential Revision: D5010689
fbshipit-source-id: 2eaa396
Summary:
This gives the option to run the biabduction analysis together with the other Clang-based checkers with the command:
infer -a checkers --biabduction -- ...
The filtering does not work yet because the filtering for the biabduction analysis matches the analyzer `Infer`, and does not filter much when the analyzer is `Checkers`, which is the case here.
Reviewed By: sblackshear
Differential Revision: D4773834
fbshipit-source-id: 16300cc
Summary:
Title.
The way types are printed is completely valid, but little weird for some C++ programmers:
`int const` - same as `const int`
`int * const` - pointer is `const`, value under it is not
`int const *` - pointer is not `const`, but the value is
`int const * const` - both pointer and value are const
Reviewed By: jberdine
Differential Revision: D4962180
fbshipit-source-id: dcb02e3
Summary:
Modify the type of `Exp.Sizeof ...` to include the value that the expression
evaluates to according to the compiler, or None if it cannot be known
statically.
Use this information in inferbo.
Mostly unused in the BiAbduction checker for now, although it could be useful
there too.
update-submodule: facebook-clang-plugins
Reviewed By: mbouaziz
Differential Revision: D4953634
fbshipit-source-id: be0999d
Summary:
- Use Logging for logging
- Add a few extra debug (not ON by default)
- No space before colon
Depends on D4961957
Reviewed By: KihongHeo
Differential Revision: D4961989
fbshipit-source-id: 7c8697d
Summary:
- Bottom-lift abstract memory domain to express unreachable node
- Two cases to make a node unreachable
+ constant: when an evaluation result of condition expression is
bottom or false, e.g., "prune(0)".
+ alias: when the same structure e is compared to itself with "<",
">", and "!=", e.g., "prune(e < e)".
- Add test for the new prune (prune_constant.c, prune_alias.c)
- Debug the semantics of comparison
Reviewed By: mbouaziz
Differential Revision: D4938055
fbshipit-source-id: d0fadf0
Summary:
We want to stop supporting '-multiletter' options altogether in the future as
they are not standard.
For boolean switches, we used to have '-short' for true and '-nshort' for
false, but that second form is necessarily > 1 letters, which doesn't work in
this scheme. Replace these by '-s' for true and '-S' for false.
Reviewed By: jberdine
Differential Revision: D4674079
fbshipit-source-id: 95bacfe
Summary:
All intermediate `.exp` files used for tests can be generated with custom info, based on what is needed for the tests purposes.
This customisation happens via command-line argument `--issues-fields`.
Reviewed By: cristianoc, jvillard
Differential Revision: D4628062
fbshipit-source-id: feaa382
Summary:
Sometimes some instructions were never part of any CFG node and were not written to CFG at all. Add a mechanism that will create node and add them to CFG when they reach compoundStmt translation.
This is step forward to make `*x;` instruction actualy dereference x (it works in C already in C++ AST looks different though)
Reviewed By: dulmarod
Differential Revision: D4469139
fbshipit-source-id: b03b11c
Summary: These direct tests were still mostly relying on PHONY targets.
Reviewed By: jberdine
Differential Revision: D4326469
fbshipit-source-id: 37b2d0a
Summary:
When calling function g_realloc(gpointer mem,gsize n_bytes) one of the spec considers the case
whereby n_bytes is zero. In that case g_realloc would return null.
If we call with sizeof(int), infer would compare sizeof(int) with zero. But the prover would fail to
understand that sizeof(int) != 0.
This diff fix this. We try to convert expression to constant when they can be converted (eg in case of sizeof).
The method currently make a partial set of conversion. This could be extended.
Reviewed By: jberdine
Differential Revision: D4166944
fbshipit-source-id: 3ec4fd7
Summary:
Currently cfg nodes are written into dot files in whatever order they
appear in a hash table. This seems unnecessarily sensitive, so this
diff sorts the nodes.
Reviewed By: dulmarod
Differential Revision: D4232377
fbshipit-source-id: a907cc6
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: These are dangerous if you are trying to compare a type to a string, and they're also unsightly.
Reviewed By: jvillard
Differential Revision: D4189956
fbshipit-source-id: 14ce127
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:
`make` doesn't delay variable evaluation in targets' dependencies, so
`$(OBJECTS)` was always empty. Including clang.make after having defined
`OBJECTS` fixes it.
Reviewed By: jberdine
Differential Revision: D4159522
fbshipit-source-id: 6925f8a
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
Summary:
This makes the tests depend on much fewer phony targets, thus reducing the need
to rerun the tests when nothing has changed.
Reviewed By: jberdine
Differential Revision: D4118457
fbshipit-source-id: 664b6e3
Summary:
In several places the tests were using whatever 'infer' executable was
found in PATH, instead of the one build from the source to be tested.
Reviewed By: jeremydubreil
Differential Revision: D4065019
fbshipit-source-id: 9b65099
Summary:
This also adds `-a compile` support to `InferClang`. This is needed for the
`xcodebuild` integration, which is hard to fold into the same binary as the
rest.
Reviewed By: jberdine
Differential Revision: D4008262
fbshipit-source-id: 0bbd53f
Summary:
Create dummy functions representing the initializers of global variables. This
is so we can implement checks in the backend that can look at the initializer
expressions of global variables. We try not to create these dummy functions
when the initializer is not present, although for some reason we sometimes end
up with empty initializers.
Also add source file info to global variables in the backend (Pvar.re).
Reviewed By: sblackshear
Differential Revision: D3780238
fbshipit-source-id: 2dca87e
Summary:
This diff fixes two issues in the backend that were causing Bad_footprint
errors when abducing pointsto facts for expressions that start in an array
access and follow up with another structured access, eg `x[0].some_field`:
1. array accesses were assumed to come last in these expressions
2. the type of the root exp passed to the function that walks down the list of
offsets to apply to it was wrong in the case of arrays: it was always the
type of the whole expression instead of the root expr (eg the type of
`x[0].some_field` instead of the type of `x`).
Reviewed By: sblackshear, jeremydubreil
Differential Revision: D3800566
fbshipit-source-id: 0511604
Summary:
Infer doesn't go looking into field values when looking for unsigned
expressions, which could cause some unintended reports.
Reviewed By: sblackshear
Differential Revision: D3724232
fbshipit-source-id: 9c4cd97
Summary:
Minor stuff:
- GCCAst -> GCCAsm
- separate constants and mutable global state in cFrontend_config
- alphabetical ordering in cFrontend_config
Reviewed By: akotulski
Differential Revision: D3593858
fbshipit-source-id: 6f4d9c3
Summary:
Backend has the same treatment for all Typ.Int types and so UnaryOperator
should be translated the same for all of them
Reviewed By: jvillard
Differential Revision: D3534277
fbshipit-source-id: 8569b65
Summary:
Call infer with `--unsafe-malloc` or set `unsafe-malloc: true,` in .inferconfig to
have infer assume that `malloc()` never returns null.
closes#389
Reviewed By: jberdine
Differential Revision: D3522169
fbshipit-source-id: 6b88a16
Summary:
The extra dereference in stmtexpr was wrong. When a dereference is needed, we have a cast.
This was causing one dereference too many, and creating wrong results.
Reviewed By: akotulski
Differential Revision: D3393294
fbshipit-source-id: 7a1ec8e
Summary:
The philosophy of the tracing mode reporting is to not report the errors in a method if reaching this error does depend on information that can be false at call site. Typically with:
void foo(Object obj, int x) {
if (x == 3) {
obj.toString();
}
}
it may be that we always call `foo` with a non-null parameter or `x != 3`.
Thechnically, the reporting code matches the pairs of the form (precondition, error) and filtering out the cases where the precondtions was not imposing constraints on the calling context, and report the other cases. So the NPE could be reported in the following case:
void bar() {
foo(null, 3);
}
However, we were missing the case where there was anyway no way to call a method in a safe way, i.e. all the preconditions were of the form: (precondition, error), for example:
void baz(boolean b) {
if (b) {
foo(null, 3);
} else {
foo(null, 3);
}
}
In that case, the summary is of the form
PRE (1): b = false
POST: NullPointerException
PRE (2): b = true
POST: NullPointerException
In which case it is legit to report `NullPointerException` in `baz`.
Reviewed By: sblackshear, jberdine
Differential Revision: D3220501
fb-gh-sync-id: 7fb7d70
fbshipit-source-id: 7fb7d70
Summary:Local variable created by conditional operator translation is now declared in scope of whole
procedure. Semantically there is no difference, hopefuly backend will not complain about this
change. Also, nullifying that variable is deferred to preanalysis instead of calling it manually
Reviewed By: jvillard
Differential Revision: D3155733
fb-gh-sync-id: 6cec8fc
fbshipit-source-id: 6cec8fc
Summary:BinaryConditionalOperator should evaluate condition expression once, but we used to evaluate it twice.
Fix translation to account for it.
Reviewed By: dulmarod
Differential Revision: D3179803
fb-gh-sync-id: a801a7e
fbshipit-source-id: a801a7e
Summary:public
When a conditional is the last instruction, there will be a join node leading directly to the exit node.
Some instructions, such as nullification of dead variables, and abstraction, are added to the control flow graph automatically. But, join nodes cannot contain instructions. So when a procedure ends with a conditional, there might be no place to store these instructions.
This diff adds one extra node between the join and the exit node in that situation.
Reviewed By: jvillard
Differential Revision: D3179056
fb-gh-sync-id: 2b9cd7e
fbshipit-source-id: 2b9cd7e
Summary:public
Instead of translating code from headers blindly, translate only gets transitively referenced from source code.
It won't translate functions from system headers, but in the future we could do that as well
since most of them aren't used and it shouldn't add much overhead.
For now this functionality is hidden behind --cxx-experimental flag
Reviewed By: dulmarod
Differential Revision: D3163519
fb-gh-sync-id: 0c53b10
fbshipit-source-id: 0c53b10
Summary:public This also required a refactoring of InitListExpr.
The idea is that ImplicitValueInitExpr can stand for initialising a whole struct,
so we translating as a list of zero expressions, according to the struct's fields,
which is then paired with a list of field expressions, such that one get a list of
assignment instructions.
Reviewed By: ddino
Differential Revision: D2999875
fb-gh-sync-id: 7f609a0
shipit-source-id: 7f609a0
Summary:public
Running clang-format on symbolic link replaced it with another file.
This is second diff out of two to fix that problem.
Reviewed By: jvillard
Differential Revision: D2960206
fb-gh-sync-id: 0f21a8f
shipit-source-id: 0f21a8f
Summary:public
Running clang-format on symbolic link replaced it with another file.
This is first diff out of two to fix that problem.
Reviewed By: jvillard
Differential Revision: D2960204
fb-gh-sync-id: aaa3231
shipit-source-id: aaa3231
Summary:
public
It turns out that C-like structs in C++ may have methods generated by clang (constructors for example).
If struct has a method, it needs to have Sil.Class type - make all CXXRecordDecls Sil.Class types by default.
Reviewed By: cristianoc
Differential Revision: D2895567
fb-gh-sync-id: 8eb18c3
Jia Chen
Kihong Heo
Sungkeun Cho
Mehdi Bouaziz
Jules Villard
Jeremy Dubreil
Dulma Churchill
Andrzej Kotulski
Martino Luca
Kihong Heo
Dino Distefano
Josh Berdine
Sam Blackshear
Cristiano Calcagno