Summary:
Previously, we would translate `throw` with `return`. However, `throw` in
ObjC/C++ is often used to mean "abort". We now translate `throw` the same as
`exit` to prune these paths.
Reviewed By: akotulski
Differential Revision: D3594156
fbshipit-source-id: 81083bb
Summary:
When analyzing C model in C++, we were seeing some SKIP function triggered by generated constructors/operators= for C structs.
In C they weren't present, but in C++ compiler generates them for us. To avoid this (and future) problems
with models, translate all functions that are needed when computing the model
Reviewed By: dulmarod
Differential Revision: D3561873
fbshipit-source-id: f8ad2a0
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:
To specify a new flag to run some test using our framework, one currently has
to add a new argument to the method that runs Infer and modify existing methods
to give a default value to that argument everywhere. With this diff, it's
possible to just specify extra arguments as parameters to
`createCInferCommand()` et al.
Reviewed By: martinoluca
Differential Revision: D3522161
fbshipit-source-id: 1499fc2
Summary:
When clang instantiates template function with argument pack, it will
give the same name to all parameters coming from the pack. To avoid
name collisions, always add index of argument's position to mangled part
of the variable.
Seemingly unrelated changes are to make existing tests pass (don't use
simple variable name where it matters)
Reviewed By: dulmarod
Differential Revision: D3503608
fbshipit-source-id: 794093a
Summary: Those functions have simple enough implementations for infer to understand them
Reviewed By: jvillard
Differential Revision: D3463084
fbshipit-source-id: f84160f
Summary:
Assume that std::vector::resize will always create nonempty vector. While this is clearly
wrong for resize(0), it removes many FPs for `resize(n)` calls, where value of `n` is unknown.
Without it, infer was thinking that `n` could be 0 and reported empty vector access.
Reviewed By: jvillard
Differential Revision: D3424355
fbshipit-source-id: cb476de
Summary:
Array types where the length is not statically known were represented
using fresh variables. This diff:
- Makes array type length optional, reducing the amount of work needed
for renaming, substitution, and normalization.
- Revises uses of array length so that the length component of a
Tarray type represents only the statically determined constant
length of an array type, and the length component of a Sizeof
expression represents the dynamically determined length of an array
value.
- Restricts the type of static lengths from a general expression
(Sil.exp) to an integer (Sil.Int.t), enforcing that static types are
constant. This in particular ensures that types contain no
variables, and so are invariant under operations such as renaming
and substitution.
- Removes the type substitution and renaming functions typ_sub,
typ_normalize, and typ_captured_ren. Now that array type lengths
are constant integers, all of these functions are the identity.
Reviewed By: cristianoc
Differential Revision: D3387343
fbshipit-source-id: b5db768
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:
Pass object by reference every time struct object is passed by value
in C++. Do it only for C++/objC++ where we have guarantee that the
object which is passed will be temporary one (created by copy constructor).
Reviewed By: jberdine
Differential Revision: D3346271
fbshipit-source-id: d3e5daa
Summary:
Make analyzer find out when null dereference comes from std::vector method.
If it does, it means that it's really empty vector access (due to the
way infer models std::vector)
Reviewed By: sblackshear
Differential Revision: D3327933
fbshipit-source-id: b9e11d6
Summary:
Turns out, analyzer was getting confused with complicated
model and it was reporting empty access in places it
shouldn't. Fixing backend is not trivial (tracing mode is the answer),
but the model can be simplified.
It introduces the problem that get() method doesn't return fresh value
every time, but we should be able to change backend later to deal with it.
Reviewed By: sblackshear
Differential Revision: D3328228
fbshipit-source-id: dddbaf8
Summary:
Create model of C++ std::vector to find occurrences when vector which might be empty is accessed. Do it by triggering null dereference every time empty vector access is performed.
Note: model will be used only when c++11 (or c++14) are used.
Reviewed By: sblackshear
Differential Revision: D3276203
fbshipit-source-id: 420a95a
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