Teach trackNullOrUndefValue() how to look through PseudoObjectExprs to find
the underlying method call for property getters. This makes over-suppression
of 'return nil' in getters consistent with the similar over-suppression for
method and function calls.
rdar://problem/24437252
llvm-svn: 265839
In ObjCMethodCall:getRuntimeDefinition(), if the method is an accessor in a
category, and it doesn't have a self declaration, first try to find the method
in a class extension. This works around a bug in Sema where multiple accessors
are synthesized for properties in class extensions that are redeclared in a
category. The implicit parameters are not filled in for the method on the
category, which causes a crash when trying to synthesize a getter for the
property in BodyFarm. The Sema bug is tracked as rdar://problem/25481164.
rdar://problem/25056531
llvm-svn: 265103
Change body autosynthesis to use the BodyFarm-synthesized body even when
an actual body exists. This enables the analyzer to use the simpler,
analyzer-provided body to model the behavior of the function rather than trying
to understand the actual body. Further, this makes the analyzer robust against
changes in headers that expose the implementations of those bodies.
rdar://problem/25145950
llvm-svn: 264687
Change the nullability checker to not warn along paths where null is returned from
a method with a non-null return type, even when the diagnostic for this return
has been suppressed. This prevents warning from methods with non-null return types
that inline methods that themselves return nil but that suppressed the diagnostic.
Also change the PreconditionViolated state component to be called "InvariantViolated"
because it is set when a post-condition is violated, as well.
rdar://problem/25393539
llvm-svn: 264647
The -dealloc method in CIFilter is highly unusual in that it will release
instance variables belonging to its *subclasses* if the variable name
starts with "input" or backs a property whose name starts with "input".
Subclasses should not release these ivars in their own -dealloc method --
doing so could result in an over release.
Before this commit, the DeallocChecker would warn about missing releases for
such "input" properties -- which could cause users of the analyzer to add
over releases to silence the warning.
To avoid this, DeallocChecker now treats CIFilter "input-prefixed" ivars
as MustNotReleaseDirectly and so will not require a release. Further, it
will now warn when such an ivar is directly released in -dealloc.
rdar://problem/25364901
llvm-svn: 264463
Add the wide character strdup variants (wcsdup, _wcsdup) and the MSVC
version of alloca (_alloca) and other differently named function used
by the Malloc checker.
A patch by Alexander Riccio!
Differential Revision: http://reviews.llvm.org/D17688
llvm-svn: 262894
exactly the same as clang's existing [[clang::fallthrough]] attribute, which
has been updated to have the same semantics. The one significant difference
is that [[fallthrough]] is ill-formed if it's not used immediately before a
switch label (even when -Wimplicit-fallthrough is disabled). To support that,
we now build a CFG of any function that uses a '[[fallthrough]];' statement
to check.
In passing, fix some bugs with our support for statement attributes -- in
particular, diagnose their use on declarations, rather than asserting.
llvm-svn: 262881
Add an -analyzer-config 'nullability:NoDiagnoseCallsToSystemHeaders' option to
the nullability checker. When enabled, this option causes the analyzer to not
report about passing null/nullable values to functions and methods declared
in system headers.
This option is motivated by the observation that large projects may have many
nullability warnings. These projects may find warnings about nullability
annotations that they have explicitly added themselves higher priority to fix
than warnings on calls to system libraries.
llvm-svn: 262763
In dealloc methods, the analyzer now warns when -dealloc is called directly on
a synthesized retain/copy ivar instead of -release. This is intended to find mistakes of
the form:
- (void)dealloc {
[_ivar dealloc]; // Mistaken call to -dealloc instead of -release
[super dealloc];
}
rdar://problem/16227989
llvm-svn: 262729
This prevents false negatives when a -dealloc method, for example, removes itself as
as an observer with [[NSNotificationCenter defaultCenter] removeObserver:self]. It is
unlikely that passing 'self' to a system header method will release 'self''s instance
variables, so this is unlikely to produce false positives.
A challenge here is that while CheckObjCDealloc no longer treats these calls as
escaping, the rest of the analyzer still does. In particular, this means that loads
from the same instance variable before and after a call to a system header will
result in different symbols being loaded by the region store. To account for this,
the checker now treats different ivar symbols with the same instance and ivar decl as
the same for the purpose of release checking and more eagerly removes a release
requirement when an instance variable is assumed to be nil. This was not needed before
because when an ivar escaped its release requirement was always removed -- now the
requirement is not removed for calls to system headers.
llvm-svn: 262261
Change "use of 'self' after it has been freed with call to [super dealloc]" to
"use of 'self' after it has been deallocated" and "use of instance variable
'_ivar' after the instance has been freed with call to [super dealloc]" to
"use of instance variable '_ivar' after 'self' has been deallocated".
llvm-svn: 261945
Referring to 'self' after a call to [super dealloc] is a use-after-free in
Objective-C because NSObject's -dealloc frees the memory pointed to by self.
This patch extends the ObjCSuperDeallocChecker to catch this error.
rdar://problem/6953275
Differential Revision: http://reviews.llvm.org/D17528
llvm-svn: 261935
This reapplies "[analyzer] Make ObjCDeallocChecker path sensitive." (r261917)
with a fix for an error on some bots about specializing a template
from another namespace.
llvm-svn: 261929
Convert the ObjCDeallocChecker to be path sensitive. The primary
motivation for this change is to prevent false positives when -dealloc calls
helper invalidation methods to release instance variables, but it additionally
improves precision when -dealloc contains control flow. It also reduces the need
for pattern matching. The check for missing -dealloc methods remains AST-based.
Part of rdar://problem/6927496
Differential Revision: http://reviews.llvm.org/D17511
llvm-svn: 261917
When looking up the 'self' decl in block captures, make sure to find the actual
self declaration even when the block captures a local variable named 'self'.
rdar://problem/24751280
llvm-svn: 261703
This patch is intended to improve pointer arithmetic checker.
From now on it only warns when the pointer arithmetic is likely to cause an
error. For example when the pointer points to a single object, or an array of
derived types.
Differential Revision: http://reviews.llvm.org/D14203
llvm-svn: 261632
Add an alpha path checker that warns about duplicate calls to [super dealloc].
This will form the foundation of a checker that will detect uses of
'self' after calling [super dealloc].
Part of rdar://problem/6953275.
Based on a patch by David Kilzer!
Differential Revision: http://reviews.llvm.org/D5238
llvm-svn: 261545
Add a checker callback that is called when the analyzer starts analyzing a
function either at the top level or when inlined. This will be used by a
follow-on patch making the DeallocChecker path sensitive.
Differential Revision: http://reviews.llvm.org/D17418
llvm-svn: 261293
When modeling a call to a setter for a property that is synthesized to be
backed by an instance variable, don't invalidate the entire instance
but rather only the storage for the updated instance variable itself.
This still doesn't model the effect of the setter completely. It doesn't
bind the set value to the ivar storage location because doing so would cause
the set value to escape, removing valuable diagnostics about potential
leaks of the value from the retain count checker.
llvm-svn: 261243
Look through PseudoObjectExpr and OpaqueValueExprs when scanning for
release-like operations. This commit also adds additional tests in anticipation
of re-writing this as a path-sensitive checker.
llvm-svn: 260608
Now that the libcpp implementations of these methods has a branch that doesn't call
memmove(), the analyzer needs to invalidate the destination for these methods explicitly.
rdar://problem/23575656
llvm-svn: 260043
It is common for the ivars for read-only assign properties to always be stored retained,
so don't warn for a release in dealloc for the ivar backing these properties.
llvm-svn: 259998
If the class or method name case-insensitively contains the term "debug",
suppress warnings about string constants flowing to user-facing UI APIs.
llvm-svn: 259875
-analyzer-display progress option prints only function names which may be ambiguous. This patch forces AnalysisConsumer to print fully-qualified function names.
Patch by Alex Sidorin!
Differential Revision: http://reviews.llvm.org/D16804
llvm-svn: 259646
Avoids unexpected overflows while performing pointer arithmetics in 64-bit code.
Moreover, neither PointerDiffType nor 'int' can be used as a common array index
type because arrays may have size (and indexes) more than PTRDIFF_MAX but less
than SIZE_MAX.
Patch by Aleksei Sidorin!
Differential Revision: http://reviews.llvm.org/D16063
llvm-svn: 259345
We already do this for case splits introduced as a result of defensive null
checks in functions and methods, so do the same for function-like macros.
rdar://problem/19640441
llvm-svn: 259222
- Include the position of the argument on which the nullability is violated
- Differentiate between a 'method' and a 'function' in the message wording
- Test for the error message text in the tests
- Fix a bug with setting 'IsDirectDereference' which resulted in regular dereferences assumed to have call context.
llvm-svn: 259221
There are multiple, common idioms of defensive nil-checks in copy,
mutableCopy, and init methods in ObjC. The analyzer doesn't currently have the
capability to distinguish these idioms from true positives, so suppress all
warnings about returns in those families. This is a pretty blunt suppression
that we should improve later.
rdar://problem/24395811
llvm-svn: 259099
Previously the ObjC Dealloc Checker only checked classes with ivars, not
retained properties, which caused three bugs:
- False positive warnings about a missing -dealloc method in classes with only
ivars.
- Missing warnings about a missing -dealloc method on classes with only
properties.
- Missing warnings about an over-released or under-released ivar associated with
a retained property in classes with only properties.
The fix is to check only classes with at least one retained synthesized
property.
This also exposed a bug when reporting an over-released or under-released
property that did not contain a synthesize statement. The checker tried to
associate the warning with an @synthesize statement that did not exist, which
caused an assertion failure in debug builds. The fix is to fall back to the
@property statement in this case.
A patch by David Kilzer!
Part of rdar://problem/6927496
Differential Revision: http://reviews.llvm.org/D5023
llvm-svn: 258896
After r251874, readonly properties that are shadowed by a readwrite property
in a class extension no longer have an instance variable, which caused the body
farm to not synthesize getters. Now, if a readonly property does not have an
instance variable look for a shadowing property and try to get the instance
variable from there.
rdar://problem/24060091
llvm-svn: 258886
A common idiom in Objective-C initializers is for a defensive nil-check on the
result of a call to a super initializer:
if (self = [super init]) {
...
}
return self;
To avoid warning on this idiom, the nullability checker now suppress diagnostics
for returns of nil on syntactic 'return self' even in initializers with non-null
return types.
llvm-svn: 258461
In r256567 I changed the nullability checker to suppress warnings about returning a null
value from a function/method with a non-null return type when the type of the returned
expression is itself nonnull. This enables the programmer to silence nullability warnings
by casting to _Nonnull:
return (SomeObject * _Nonnull)nil;
Unfortunately, under ObjC automated reference counting, Sema adds implicit casts to
_Nonnull to return expressions of nullable or unspecified types in functions with
non-null function/method return types. With r256567, these casts cause all nullability
warnings for returns of reference-counted types to be suppressed under ARC, leading to
false negatives.
This commit updates the nullability checker to look through implicit casts before
determining the type of the returned expression. It also updates the tests to turn on
ARC for the nullability_nullonly.mm testfile and adds a new testfile to test when ARC
is turned off.
rdar://problem/24200117
llvm-svn: 258061
Make sure that we do not add SymbolCast at the very boundary of
the range in which the cast would not certainly happen.
Differential Revision: http://reviews.llvm.org/D16178
llvm-svn: 258039
Update NullabilityChecker so that it checks return statements in ObjC methods.
Previously it was returning early because methods do not have a function type.
Also update detection of violated parameter _Nonnull preconditions to handle
ObjC methods.
rdar://problem/24200560
llvm-svn: 257938
Provide separate visitor templates for the three hierarchies, and also
the `FullSValVisitor' class, which is a union of all three visitors.
Additionally, add a particular example visitor, `SValExplainer', in order to
test the visitor templates. This visitor is capable of explaining the SVal,
SymExpr, or MemRegion in a natural language.
Compared to the reverted r257605, this fixes the test that used to fail
on some triples, and fixes build failure under -fmodules.
Differential Revision: http://reviews.llvm.org/D15448
llvm-svn: 257893
This reverts commit r257605.
The test fails on architectures that use unsigned int as size_t.
SymbolManager.h fails with compile errors on some platforms.
llvm-svn: 257608
Provide separate visitor templates for the three hierarchies, and also
the `FullSValVisitor' class, which is a union of all three visitors.
Additionally, add a particular example visitor, `SValExplainer', in order to
test the visitor templates. This visitor is capable of explaining the SVal,
SymExpr, or MemRegion in a natural language.
Differential Revision: http://reviews.llvm.org/D15448
llvm-svn: 257605
This fix a bug in RangeSet::pin causing single value ranges to be considered non conventionally ordered.
Differential Revision: http://reviews.llvm.org/D12901
llvm-svn: 257467
The current workaround for truncations not being modelled is that the evaluation of integer to integer casts are simply bypassed and so the original symbol is used as the new casted symbol (cf SimpleSValBuilder::evalCastFromNonLoc).
This lead to the issue described in PR25078, as the RangeConstraintManager associates ranges with symbols.
The new evalIntegralCast method added by this patch wont bypass the cast if it finds the range of the symbol to be greater than the maximum value of the target type.
The fix to RangeSet::pin mentioned in the initial review will be committed separately.
Differential Revision: http://reviews.llvm.org/D12901
llvm-svn: 257464
visited decls.
Due to redeclarations, the function may have different declarations used
in CallExpr and in the definition. However, we need to use a unique
declaration for both store and lookup in VisitedCallees. This patch
fixes issues with analysis in topological order. A simple test is
included.
Patch by Alex Sidorin!
Differential Revision: http://reviews.llvm.org/D15410
llvm-svn: 257318
Devin Coughlin