The checker already warns for __block-storage variables being used as a
dispatch_once() predicate, however it refers to them as local which is not quite
accurate, so we fix that.
Differential Revision: https://reviews.llvm.org/D26159
llvm-svn: 285637
Unlike global/static variables, calloc etc. functions that allocate ObjC
objects behave differently in terms of memory barriers, and hacks that make
dispatch_once as fast as it possibly could be start failing.
Differential Revision: https://reviews.llvm.org/D25909
llvm-svn: 285605
__builtin_alloca always uses __BIGGEST_ALIGNMENT__ for the alignment of
the allocation. __builtin_alloca_with_align allows the programmer to
specify the alignment of the allocation.
This fixes PR30658.
llvm-svn: 285544
Support CFNumberRef and OSNumber objects, which may also be accidentally
converted to plain integers or booleans.
Enable explicit boolean casts by default in non-pedantic mode.
Improve handling for warnings inside macros.
Improve error messages.
Differential Revision: https://reviews.llvm.org/D25731
llvm-svn: 285533
This patch contains 2 improvements to the CFNumber checker:
- Checking of CFNumberGetValue misuse.
- Treating all CFNumber API misuse errors as non-fatal. (Previously we treated errors that could cause uninitialized memory as syncs and the truncation errors as non-fatal.)
This implements a subset of functionality from https://reviews.llvm.org/D17954.
Differential Revision: https://reviews.llvm.org/D25876
llvm-svn: 285253
This checker does not emit reports, however it influences the analysis
by providing complete summaries for, or otherwise improving modeling of,
various standard library functions.
This should reduce the number of infeasible paths explored during analysis.
The custom function summary format used in this checker is superior to
body farms by causing less unnecessary state splits,
which would result in better analysis performance.
Differential Revision: https://reviews.llvm.org/D20811
llvm-svn: 284960
In macros, 'do {...} while (0)' is often used. Don't warn about the condition 0 when it is unreachable.
Differential Revision: https://reviews.llvm.org/D25606
llvm-svn: 284477
When dealing with objects that represent numbers, such as Objective-C NSNumber,
the language provides little protection from accidentally interpreting
the value of a pointer to such object as the value of the number represented
by the object. Results of such mis-interpretation may be unexpected.
The checker attempts to fill this gap in cases when the code is obviously
incorrect.
With "Pedantic" option enabled, this checker enforces a coding style to
completely prevent errors of this kind (off by default).
Differential Revision: https://reviews.llvm.org/D22968
llvm-svn: 284473
This reverts commit r284335.
It appears to be causing test-suite compile-time and execution-time
performance measurements to take longer than expected on several bots.
This is surprising, because r284335 is a static-analyzer-only change.
llvm-svn: 284340
Add additional checking to MallocChecker to avoid crashing when memory
routines have unexpected numbers of arguments. You wouldn't expect to see much
of this in normal code (-Wincompatible-library-redeclaration warns on this),
but, for example, CMake tests can generate these.
This is PR30616.
rdar://problem/28631974
llvm-svn: 284335
Revert:
r283662: [analyzer] Re-apply r283093 "Add extra notes to ObjCDeallocChecker"
r283660: [analyzer] Fix build error after r283660 - remove constexpr strings.
It was causing an internal build bot to fail. It looks like in some cases
adding an extra note can cause scan-build plist output to drop a diagnostic
altogether.
llvm-svn: 284317
AST matchers are useful for the analyzer's checkers.
More patches on particular checkers shall follow.
This is the first time clang binary gets linked to ASTMatchers.
The binary size increase for the clang executable would be
+0.5% in release mode, +2% in debug mode.
Differential Revision: https://reviews.llvm.org/D25429
llvm-svn: 284112
On macOS (but not iOS), if an ObjC property has no setter, the nib-loading code
for an IBOutlet is documented as directly setting the backing ivar without
retaining the value -- even if the property is 'retain'.
This resulted in false positives from the DeallocChecker for code that did not
release such ivars in -dealloc.
To avoid these false positives, treat IBOutlet ivars that back a property
without a setter as having an unknown release requirement in macOS.
rdar://problem/28507353
llvm-svn: 284084
Highlight code clones referenced by the warning message with the help of
the extra notes feature recently introduced in r283092.
Change warning text to more clang-ish. Remove suggestions from the copy-paste
error checker diagnostics, because currently our suggestions are strictly 50%
wrong (we do not know which of the two code clones contains the error), and
for that reason we should not sound as if we're actually suggesting this.
Hopefully a better solution would bring them back.
Make sure the suspicious clone pair structure always mentions
the correct variable for the second clone.
Differential Revision: https://reviews.llvm.org/D24916
llvm-svn: 283094
The report is now highlighting instance variables and properties
referenced by the warning message with the help of the
extra notes feature recently introduced in r283092.
Differential Revision: https://reviews.llvm.org/D24915
llvm-svn: 283093
Example:
switch (x) {
int a; // <- This is unreachable but needed
case 1:
a = ...
Differential Revision: https://reviews.llvm.org/D24905
llvm-svn: 282574
The class BodyFarm creates bodies for
OSAtomicCompareAndSwap*, objc_atomicCompareAndSwap*, dispatch_sync*, dispatch_once*
and for them the flag isBodyAutosynthesized is set to true.
This diff
1. makes AnalysisConsumer::HandleCode skip the autosynthesized code
2. replaces assert(LCtx->getParent()) in RetainCountChecker::checkEndFunction
by assert(!LCtx->inTopFrame()) (minor cleanup)
Test plan: make -j8 check-clang-analysis
Differential revision: https://reviews.llvm.org/D24792
llvm-svn: 282293
This checker should find the calls to blocking functions (for example: sleep, getc, fgets,read,recv etc.) inside a critical section. When sleep(x) is called while a mutex is held, other threads cannot lock the same mutex. This might take some time, leading to bad performance or even deadlock.
Example:
mutex_t m;
void f() {
sleep(1000); // Error: sleep() while m is locked! [f() is called from foobar() while m is locked]
// do some work
}
void foobar() {
lock(m);
f();
unlock(m);
}
A patch by zdtorok (Zoltán Dániel Török)!
Differential Revision: https://reviews.llvm.org/D21506
llvm-svn: 282011
ArrayBoundChecker did not detect out of bounds memory access errors in case an
array was allocated by the new expression. This patch resolves this issue.
Patch by Daniel Krupp!
Differential Revision: https://reviews.llvm.org/D24307
llvm-svn: 281934
For ObjC type parameter, we used to have TypedefType that is canonicalized to
id or the bound type. We can't represent "T <protocol>" and thus will lose
the type information in the following example:
@interface MyMutableDictionary<KeyType, ObjectType> : NSObject
- (void)setObject:(ObjectType)obj forKeyedSubscript:(KeyType <NSCopying>)key;
@end
MyMutableDictionary<NSString *, NSString *> *stringsByString;
NSNumber *n1, *n2;
stringsByString[n1] = n2;
--> no warning on type mismatch of the key.
To fix the problem, we introduce a new type ObjCTypeParamType that supports
a list of protocol qualifiers.
We create ObjCTypeParamType for ObjCTypeParamDecl when we create
ObjCTypeParamDecl. We also substitute ObjCTypeParamType instead of TypedefType
on an ObjCTypeParamDecl.
rdar://24619481
rdar://25060179
Differential Revision: http://reviews.llvm.org/D23080
llvm-svn: 281358
This patch also introduces AnalysisOrderChecker which is intended for testing
of callback call correctness.
Differential Revision: https://reviews.llvm.org/D23804
llvm-svn: 280367
Fix a crash when relexing the underlying memory buffer to find incorrect
arguments to NSLocalizedString(). With precompiled headers, the raw
buffer may be NULL. Instead, use the source manager to get the buffer,
which will lazily create the buffer for precompiled headers.
rdar://problem/27429091
llvm-svn: 280174
This replaces the old approach of fingerprinting every AST node into a string,
which avoided collisions and was simple to implement, but turned out to be
extremely ineffective with respect to both performance and memory.
The collisions are now dealt with in a separate pass, which no longer causes
performance problems because collisions are rare.
Patch by Raphael Isemann!
Differential Revision: https://reviews.llvm.org/D22515
llvm-svn: 279378
The original clone checker tries to find copy-pasted code that is exactly
identical to the original code, up to minor details.
As an example, if the copy-pasted code has all references to variable 'a'
replaced with references to variable 'b', it is still considered to be
an exact clone.
The new check finds copy-pasted code in which exactly one variable seems
out of place compared to the original code, which likely indicates
a copy-paste error (a variable was forgotten to be renamed in one place).
Patch by Raphael Isemann!
Differential Revision: https://reviews.llvm.org/D23314
llvm-svn: 279056
This new checker tries to find execution paths on which implicit integral casts
cause definite loss of information: a certainly-negative integer is converted
to an unsigned integer, or an integer is definitely truncated to fit into
a smaller type.
Being implicit, such casts are likely to produce unexpected results.
Patch by Daniel Marjamäki!
Differential Revision: https://reviews.llvm.org/D13126
llvm-svn: 278941
Like SymbolConjured, SymbolMetadata also needs to be uniquely
identified by the moment of its birth.
Such moments are coded by the (Statement, LocationContext, Block count) triples.
Each such triple represents the moment of analyzing a statement with a certain
call backtrace, with corresponding CFG block having been entered a given amount
of times during analysis of the current code body.
The LocationContext information was accidentally omitted for SymbolMetadata,
which leads to reincarnation of SymbolMetadata upon re-entering a code body
with a different backtrace; the new symbol is incorrectly unified with
the old symbol, which leads to unsound assumptions.
Patch by Alexey Sidorin!
Differential Revision: https://reviews.llvm.org/D21978
llvm-svn: 278937
Change the retain count checker to treat CoreFoundation-style "CV"-prefixed
reference types from CoreVideo similarly to CoreGraphics types. With this
change, we treat CVFooRetain() on a CVFooRef type as a retain. CVFooRelease()
APIs are annotated as consuming their parameter, so this change prevents false
positives about incorrect decrements of reference counts.
<rdar://problem/27116090>
llvm-svn: 278382
Correct two comments that do not match the current behavior of the checker.
A patch by Alexander Droste!
Differential Revision: https://reviews.llvm.org/D22670
llvm-svn: 277547
Add new APIs that require localized strings and remove two APIs that were
incorrectly marked as requiring a user-facing string.
A patch by Kulpreet Chilana!
Differential Revision: https://reviews.llvm.org/D22926
llvm-svn: 277273
This patch adds the CloneDetector class which allows searching source code
for clones.
For every statement or group of statements within a compound statement,
CloneDetector computes a hash value, and finds clones by detecting
identical hash values.
This initial patch only provides a simple hashing mechanism
that hashes the kind of each sub-statement.
This patch also adds CloneChecker - a simple static analyzer checker
that uses CloneDetector to report copy-pasted code.
Patch by Raphael Isemann!
Differential Revision: https://reviews.llvm.org/D20795
llvm-svn: 276782
Summary:
This patch moves the MPIFunctionClassifier header to `clang/include/clang/StaticAnalyzer/Checkers`,
in order to make it accessible in other parts of the architecture.
Reviewers: dcoughlin, zaks.anna
Subscribers: alexfh, cfe-commits
Patch by Alexander Droste!
Differential Revision: https://reviews.llvm.org/D22671
llvm-svn: 276639
This checker checks copy and move assignment operators whether they are
protected against self-assignment. Since C++ core guidelines discourages
explicit checking for `&rhs==this` in general we take a different approach: in
top-frame analysis we branch the exploded graph for two cases, where &rhs==this
and &rhs!=this and let existing checkers (e.g. unix.Malloc) do the rest of the
work. It is important that we check all copy and move assignment operator in top
frame even if we checked them already since self-assignments may happen
undetected even in the same translation unit (e.g. using random indices for an
array what may or may not be the same).
This reapplies r275820 after fixing a string-lifetime issue discovered by the
bots.
A patch by Ádám Balogh!
Differential Revision: https://reviews.llvm.org/D19311
llvm-svn: 276365
This checker checks copy and move assignment operators whether they are
protected against self-assignment. Since C++ core guidelines discourages
explicit checking for `&rhs==this` in general we take a different approach: in
top-frame analysis we branch the exploded graph for two cases, where &rhs==this
and &rhs!=this and let existing checkers (e.g. unix.Malloc) do the rest of the
work. It is important that we check all copy and move assignment operator in top
frame even if we checked them already since self-assignments may happen
undetected even in the same translation unit (e.g. using random indices for an
array what may or may not be the same).
A patch by Ádám Balogh!
Differential Revision: https://reviews.llvm.org/D19311
llvm-svn: 275820
This encourages checkers to make logical decisions depending on
value of which region was the symbol under consideration
introduced to denote.
A similar technique is already used in a couple of checkers;
they were modified to call the new method.
Differential Revision: http://reviews.llvm.org/D22242
llvm-svn: 275290
Like with SenTestCase, subclasses of XCTestCase follow a "tear down" idiom to
release instance variables and so typically do not release ivars in -dealloc.
This commit applies the existing special casing for SenTestCase to XCTestCase
as well.
rdar://problem/25884696
llvm-svn: 273441
This is a speculative attempt to fix the compiler error: "list initialization inside
member initializer list or non-static data member initializer is not implemented" with
r272529.
llvm-svn: 272530
This commit adds a static analysis checker to verify the correct usage of the MPI API in C
and C++. This version updates the reverted r271981 to fix a memory corruption found by the
ASan bots.
Three path-sensitive checks are included:
- Double nonblocking: Double request usage by nonblocking calls without intermediate wait
- Missing wait: Nonblocking call without matching wait.
- Unmatched wait: Waiting for a request that was never used by a nonblocking call
Examples of how to use the checker can be found at https://github.com/0ax1/MPI-Checker
A patch by Alexander Droste!
Reviewers: zaks.anna, dcoughlin
Differential Revision: http://reviews.llvm.org/D21081
llvm-svn: 272529
Second try at reapplying
"[analyzer] Add checker for correct usage of MPI API in C and C++."
Special thanks to Dan Liew for helping test the fix for the template
specialization compiler error with gcc.
The original patch is by Alexander Droste!
Differential Revision: http://reviews.llvm.org/D12761
llvm-svn: 271977
Reapply r271907 with a fix for the compiler error with gcc about specializing
clang::ento::ProgramStateTrait in a different namespace.
Differential Revision: http://reviews.llvm.org/D12761
llvm-svn: 271914
This commit adds a static analysis checker to check for the correct usage of the
MPI API in C and C++.
3 path-sensitive checks are included:
- Double nonblocking: Double request usage by nonblocking calls
without intermediate wait.
- Missing wait: Nonblocking call without matching wait.
- Unmatched wait: Waiting for a request that was never used by a
nonblocking call.
Examples of how to use the checker can be found
at https://github.com/0ax1/MPI-Checker
Reviewers: zaks.anna
A patch by Alexander Droste!
Differential Revision: http://reviews.llvm.org/D12761
llvm-svn: 271907
Summary:
Leaking a stack address via a static variable refers to it in the diagnostic as a 'global'. This patch corrects the diagnostic for static variables.
Patch by Phil Camp, SN Systems
Reviewers: dcoughlin, zaks.anna
Subscribers: xazax.hun, cfe-commits
Differential Revision: http://reviews.llvm.org/D19866
Patch by Phil Camp
llvm-svn: 270849
The function strcmp() can return any value, not just {-1,0,1} : "The strcmp(const char *s1, const char *s2) function returns an integer greater than, equal to, or less than zero, accordingly as the string pointed to by s1 is greater than, equal to, or less than the string pointed to by s2." [C11 7.24.4.2p3]
https://llvm.org/bugs/show_bug.cgi?id=23790http://reviews.llvm.org/D16317
llvm-svn: 270154
Fix a crash in the generics checker where DynamicTypePropagation tries
to get the superclass of a root class.
This is a spot-fix for a deeper issue where the checker makes assumptions
that may not hold about subtyping between the symbolically-tracked type of
a value and the compile-time types of a cast on that value.
I've added a TODO to address the underlying issue.
rdar://problem/26086914
llvm-svn: 269227
If an address of a field is passed through a const pointer,
the whole structure's base region should receive the
TK_PreserveContents trait and avoid invalidation.
Additionally, include a few FIXME tests shown up during testing.
Differential Revision: http://reviews.llvm.org/D19057
llvm-svn: 267413
Update the nullability checker to allow an explicit cast to nonnull to
suppress a warning on an assignment of nil to a nonnull:
id _Nonnull x = (id _Nonnull)nil; // no-warning
This suppression as already possible for diagnostics on returns and
function/method arguments.
rdar://problem/25381178
llvm-svn: 266219
Treat a _Nonnull ivar that is nil as an invariant violation in a similar
fashion to how a nil _Nonnull parameter is treated as a precondition violation.
This avoids warning on defensive returns of nil on defensive internal
checks, such as the following common idiom:
@class InternalImplementation
@interface PublicClass {
InternalImplementation * _Nonnull _internal;
}
-(id _Nonnull)foo;
@end
@implementation PublicClass
-(id _Nonnull)foo {
if (!_internal)
return nil; // no-warning
return [_internal foo];
}
@end
rdar://problem/24485171
llvm-svn: 266157
The nullability checker can sometimes miss detecting nullability precondition
violations in inlined functions because the binding for the parameter
that violated the precondition becomes dead before the return:
int * _Nonnull callee(int * _Nonnull p2) {
if (!p2)
// p2 becomes dead here, so binding removed.
return 0; // warning here because value stored in p2 is symbolic.
else
return p2;
}
int *caller(int * _Nonnull p1) {
return callee(p1);
}
The fix, which is quite blunt, is to not warn about null returns in inlined
methods/functions. This won’t lose much coverage for ObjC because the analyzer
always analyzes each ObjC method at the top level in addition to inlined. It
*will* lose coverage for C — but there aren’t that many codebases with C
nullability annotations.
rdar://problem/25615050
llvm-svn: 266109
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
The range here isn't over references, so using `auto &` here incites a
copy. Switching to `auto *` would do, but we might as well list an
explicit type for clarity.
Found by -Wrange-loop-analysis.
llvm-svn: 264071
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
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
Artem Dergachev