TODO: support realloc(). Currently it is not possible due to the present realloc() handling. Currently RegionState is not being attached to realloc() in case of a zero Size argument.
llvm-svn: 234889
This is imitating a pre-r228174 state where ivars are not considered tracked by
default, but with the addition that even ivars /with/ retain count information
(e.g. "[_ivar retain]; [ivar _release];") are not being tracked as well. This is
to ensure that we don't regress on values accessed through both properties and
ivars, which is what r228174 was trying to fix.
The issue occurs in code like this:
[_contentView retain];
[_contentView removeFromSuperview];
[self addSubview:_contentView]; // invalidates 'self'
[_contentView release];
In this case, the call to -addSubview: may change the value of self->_contentView,
and so the analyzer can't be sure that we didn't leak the original _contentView.
This is a correct conservative view of the world, but not a useful one. Until we
have a heuristic that allows us to not consider this a leak, not emitting a
diagnostic is our best bet.
This commit disables all of the ivar-related retain count tests, but does not
remove them to ensure that we don't crash trying to evaluate either valid or
erroneous code. The next commit will add a new test for the example above so
that this commit (and the previous one) can be reverted wholesale when a better
solution is implemented.
Rest of rdar://problem/20335433
llvm-svn: 233592
Give up this checking in order to continue tracking that these values came from
direct ivar access, which will be important in the next commit.
Part of rdar://problem/20335433
llvm-svn: 233591
Similarly, don't assume +0 if the property's setter is manually implemented.
In both cases, if the property's ownership is explicitly written, then we /do/
assume the ivar has the same ownership.
rdar://problem/20218183
llvm-svn: 232849
Now that SmallString is a first-class citizen, most SmallString::str()
calls are not required. This patch removes a whole bunch of them, yet
there are lots more.
There are two use cases where str() is really needed:
1) To use one of StringRef member functions which is not available in
SmallString.
2) To convert to std::string, as StringRef implicitly converts while
SmallString do not. We may wish to change this, but it may introduce
ambiguity.
llvm-svn: 232622
They're expensive to compare and we won't sort many of them so std::sort
doesn't give any benefits and causes code bloat. Func fact: clang -O3 didn't
even bother to inline libc++'s std::sort here.
While there validate the predicate a bit harder, the sort is unstable and we
don't want to introduce any non-determinism. I had to spell out the function
pointer type because GCC 4.7 still fails to convert the lambda to a function
pointer :(
No intended functionality change.
llvm-svn: 232263
CloudABI also supports the arc4random() function. We can enable compiler
warnings for rand(), random() and *rand48() on this system as well.
llvm-svn: 231914
In theory we could assume a CF property is stored at +0 if there's not a custom
setter, but that's not really worth the complexity. What we do know is that a
CF property can't have ownership attributes, and so we shouldn't assume anything
about the ownership of the ivar.
rdar://problem/20076963
llvm-svn: 231553
Binding __builtin_alloca() return value to the symbolic value kills previous binding to a AllocaRegion established by the core.BuiltinFunctions checker. Other checkers may rely upon this information. Rollback handling of __builtin_alloca() to the way prior to r229850.
llvm-svn: 231160
We expect in general that any nil value has no retain count information
associated with it; violating this results in unexpected state unification
/later/ when we decide to throw the information away. Unexpectedly caching
out can lead to an assertion failure or crash.
rdar://problem/19862648
llvm-svn: 229934
+ separate bug report for "Free alloca()" error to be able to customize checkers responsible for this error.
+ Muted "Free alloca()" error for NewDelete checker that is not responsible for c-allocated memory, turned on for unix.MismatchedDeallocator checker.
+ RefState for alloca() - to be able to detect usage of zero-allocated memory by upcoming ZeroAllocDereference checker.
+ AF_Alloca family to handle alloca() consistently - keep proper family in RefState, handle 'alloca' by getCheckIfTracked() facility, etc.
+ extra tests.
llvm-svn: 229850
The state obtained from CheckerContext::getState() may be outdated by the time the alloc/dealloc handling function is called (e.g. the state was modified but the transition was not performed). State argument was added to all alloc/dealloc handling functions in order to get the latest state and to allow sequential calls to those functions.
llvm-svn: 228737
to the plist output. This check_name field does not guaranteed to be the
same as the name of the checker in the future.
Reviewer: Anna Zaks
Differential Revision: http://reviews.llvm.org/D6841
llvm-svn: 228624
The analyzer thinks that ArraySubscriptExpr cannot be an r-value (ever).
However, it can be in some corner cases. Specifically, C forbids expressions
of unqualified void type from being l-values.
Note, the analyzer will keep modeling the subscript expr as an l-value. The
analyzer should be treating void* as a char array
(https://gcc.gnu.org/onlinedocs/gcc-4.3.0/gcc/Pointer-Arith.html).
llvm-svn: 228249
Instead of handling edge cases (mostly involving blocks), where we have difficulty finding
an allocation statement, allow the allocation site to be in a parent node.
Previously we assumed that the allocation site can always be found in the same frame
as allocation, but there are scenarios in which an element is leaked in a child
frame but is allocated in the parent.
llvm-svn: 228247
A refinement of r204730, itself a refinement of r198953, to better handle
cases where an object is accessed both through a property getter and
through direct ivar access. An object accessed through a property should
always be treated as +0, i.e. not owned by the caller. However, an object
accessed through an ivar may be at +0 or at +1, depending on whether the
ivar is a strong reference. Outside of ARC, we don't always have that
information.
The previous attempt would clear out the +0 provided by a getter, but only
if that +0 hadn't already participated in other retain counting operations.
(That is, "self.foo" is okay, but "[[self.foo retain] autorelease]" is
problematic.) This turned out to not be good enough when our synthesized
getters get involved.
This commit drops the notion of "overridable" reference counting and instead
just tracks whether a value ever came from a (strong) ivar. If it has, we
allow one more release than we otherwise would. This has the added benefit
of being able to catch /some/ overreleases of instance variables, though
it's not likely to come up in practice.
We do still get some false negatives because we currently throw away
refcount state upon assigning a value into an ivar. We should probably
improve on that in the future, especially once we synthesize setters as
well as getters.
rdar://problem/18075108
llvm-svn: 228174
Sorry for the noise, I managed to miss a bunch of recent regressions of
include orderings here. This should actually sort all the includes for
Clang. Again, no functionality changed, this is just a mechanical
cleanup that I try to run periodically to keep the #include lines as
regular as possible across the project.
llvm-svn: 225979
Richard rejected my Sema change to interpret an integer literal zero in
a varargs context as a null pointer, so -Wsentinel sees an integer
literal zero and fires off a warning. Only CodeGen currently knows that
it promotes integer literal zeroes in this context to pointer size on
Windows. I didn't want to teach -Wsentinel about that compatibility
hack. Therefore, I'm migrating to C++11 nullptr.
llvm-svn: 223079
This is a new form of expression of the form:
(expr op ... op expr)
where one of the exprs is a parameter pack. It expands into
(expr1 op (expr2onwards op ... op expr))
(and likewise if the pack is on the right). The non-pack operand can be
omitted; in that case, an empty pack gives a fallback value or an error,
depending on the operator.
llvm-svn: 221573
This suppresses a common false positive when analyzing libc++.
Along the way, introduce some tests to show this checker actually
works with C++ static_cast<>.
llvm-svn: 220160
Anton Yartsev