MallocChecker warns when memory is passed into -[NSData initWithBytesNoCopy]
but isn't allocated by malloc(), because it will be deallocated by free().
However, initWithBytesNoCopy has an overload that takes an arbitrary block
for deallocating the object. If such overload is used, it is no longer
necessary to make sure that the memory is allocated by malloc().
Traditionally, clang-tidy uses the term check, and the analyzer uses checker,
but in the very early years, this wasn't the case, and code originating from the
early 2010's still incorrectly refer to checkers as checks.
This patch attempts to hunt down most of these, aiming to refer to checkers as
checkers, but preserve references to callback functions (like checkPreCall) as
checks.
Differential Revision: https://reviews.llvm.org/D67140
llvm-svn: 371760
These static functions deal with ExplodedNodes which is something we don't want
the PathDiagnostic interface to know anything about, as it's planned to be
moved out of libStaticAnalyzerCore.
Differential Revision: https://reviews.llvm.org/D67382
llvm-svn: 371659
That's one of the few random entities in the PathDiagnostic interface that
are specific to the Static Analyzer. By moving them out we could let
everybody use path diagnostics without linking against Static Analyzer.
Differential Revision: https://reviews.llvm.org/D67381
llvm-svn: 371658
Checkers are now required to specify whether they're creating a
path-sensitive report or a path-insensitive report by constructing an
object of the respective type.
This makes BugReporter more independent from the rest of the Static Analyzer
because all Analyzer-specific code is now in sub-classes.
Differential Revision: https://reviews.llvm.org/D66572
llvm-svn: 371450
Write tests for the actual crash that was found. Write comments and refactor
code around 17 style bugs and suppress 3 false positives.
Differential Revision: https://reviews.llvm.org/D66847
llvm-svn: 370246
Now that we've moved to C++14, we no longer need the llvm::make_unique
implementation from STLExtras.h. This patch is a mechanical replacement
of (hopefully) all the llvm::make_unique instances across the monorepo.
Differential revision: https://reviews.llvm.org/D66259
llvm-svn: 368942
When I'm new to a file/codebase, I personally find C++'s strong static type
system to be a great aid. BugReporter.cpp is still painful to read however:
function calls are made with mile long parameter lists, seemingly all of them
taken with a non-const reference/pointer. This patch fixes nothing but this:
make a few things const, and hammer it until it compiles.
Differential Revision: https://reviews.llvm.org/D65382
llvm-svn: 368735
find clang/ -type f -exec sed -i 's/std::shared_ptr<PathDiagnosticPiece>/PathDiagnosticPieceRef/g' {} \;
git diff -U3 --no-color HEAD^ | clang-format-diff-6.0 -p1 -i
Just as C++ is meant to be refactored, right?
Differential Revision: https://reviews.llvm.org/D65381
llvm-svn: 368717
Summary:
Integer Set Library using retain-count based allocation which is not
modeled in MallocChecker.
Reviewed By: NoQ
Tags: #clang
Differential Revision: https://reviews.llvm.org/D64680
llvm-svn: 366391
Since D57922, the config table contains every checker option, and it's default
value, so having it as an argument for getChecker*Option is redundant.
By the time any of the getChecker*Option function is called, we verified the
value in CheckerRegistry (after D57860), so we can confidently assert here, as
any irregularities detected at this point must be a programmer error. However,
in compatibility mode, verification won't happen, so the default value must be
restored.
This implies something else, other than adding removing one more potential point
of failure -- debug.ConfigDumper will always contain valid values for
checker/package options!
Differential Revision: https://reviews.llvm.org/D59195
llvm-svn: 361042
new expression.
This was voted into C++20 as a defect report resolution, so we
retroactively apply it to all prior language modes (though it can never
actually be used before C++11 mode).
llvm-svn: 360006
Under the term "subchecker", I mean checkers that do not have a checker class on
their own, like unix.MallocChecker to unix.DynamicMemoryModeling.
Since a checker object was required in order to retrieve checker options,
subcheckers couldn't possess options on their own.
This patch is also an excuse to change the argument order of getChecker*Option,
it always bothered me, now it resembles the actual command line argument
(checkername:option=value).
Differential Revision: https://reviews.llvm.org/D57579
llvm-svn: 355297
This patch effectively fixes the almost decade old checker naming issue.
The solution is to assert when CheckerManager::getChecker is called on an
unregistered checker, and assert when CheckerManager::registerChecker is called
on a checker that is already registered.
Differential Revision: https://reviews.llvm.org/D55429
llvm-svn: 352292
Unfortunately, up until now, the fact that certain checkers depended on one
another was known, but how these actually unfolded was hidden deep within the
implementation. For example, many checkers (like RetainCount, Malloc or CString)
modelled a certain functionality, and exposed certain reportable bug types to
the user. For example, while MallocChecker models many many different types of
memory handling, the actual "unix.MallocChecker" checker the user was exposed to
was merely and option to this modeling part.
Other than this being an ugly mess, this issue made resolving the checker naming
issue almost impossible. (The checker naming issue being that if a checker
registered more than one checker within its registry function, both checker
object recieved the same name) Also, if the user explicitly disabled a checker
that was a dependency of another that _was_ explicitly enabled, it implicitly,
without "telling" the user, reenabled it.
Clearly, changing this to a well structured, declarative form, where the
handling of dependencies are done on a higher level is very much preferred.
This patch, among the detailed things later, makes checkers declare their
dependencies within the TableGen file Checkers.td, and exposes the same
functionality to plugins and statically linked non-generated checkers through
CheckerRegistry::addDependency. CheckerRegistry now resolves these dependencies,
makes sure that checkers are added to CheckerManager in the correct order,
and makes sure that if a dependency is disabled, so will be every checker that
depends on it.
In detail:
* Add a new field to the Checker class in CheckerBase.td called Dependencies,
which is a list of Checkers.
* Move unix checkers before cplusplus, as there is no forward declaration in
tblgen :/
* Add the following new checkers:
- StackAddrEscapeBase
- StackAddrEscapeBase
- CStringModeling
- DynamicMemoryModeling (base of the MallocChecker family)
- IteratorModeling (base of the IteratorChecker family)
- ValistBase
- SecuritySyntaxChecker (base of bcmp, bcopy, etc...)
- NSOrCFErrorDerefChecker (base of NSErrorChecker and CFErrorChecker)
- IvarInvalidationModeling (base of IvarInvalidation checker family)
- RetainCountBase (base of RetainCount and OSObjectRetainCount)
* Clear up and registry functions in MallocChecker, happily remove old FIXMEs.
* Add a new addDependency function to CheckerRegistry.
* Neatly format RUN lines in files I looked at while debugging.
Big thanks to Artem Degrachev for all the guidance through this project!
Differential Revision: https://reviews.llvm.org/D54438
llvm-svn: 352287
Introduce the boolean ento::shouldRegister##CHECKERNAME(const LangOptions &LO)
function very similarly to ento::register##CHECKERNAME. This will force every
checker to implement this function, but maybe it isn't that bad: I saw a lot of
ObjC or C++ specific checkers that should probably not register themselves based
on some LangOptions (mine too), but they do anyways.
A big benefit of this is that all registry functions now register their checker,
once it is called, registration is guaranteed.
This patch is a part of a greater effort to reinvent checker registration, more
info here: D54438#1315953
Differential Revision: https://reviews.llvm.org/D55424
llvm-svn: 352277
to reflect the new license.
We understand that people may be surprised that we're moving the header
entirely to discuss the new license. We checked this carefully with the
Foundation's lawyer and we believe this is the correct approach.
Essentially, all code in the project is now made available by the LLVM
project under our new license, so you will see that the license headers
include that license only. Some of our contributors have contributed
code under our old license, and accordingly, we have retained a copy of
our old license notice in the top-level files in each project and
repository.
llvm-svn: 351636
Accidentally commited earlier with the same commit title, but really it
should've been
"Revert rC349283 '[analyzer][MallocChecker] Improve warning messages on double-delete errors'"
llvm-svn: 349344
This patch merely reorganizes some things, and features no functional change.
In detail:
* Provided documentation, or moved existing documentation in more obvious
places.
* Added dividers. (the //===----------===// thing).
* Moved getAllocationFamily, printAllocDeallocName, printExpectedAllocName and
printExpectedDeallocName in the global namespace on top of the file where
AllocationFamily is declared, as they are very strongly related.
* Moved isReleased and MallocUpdateRefState near RefState's definition for the
same reason.
* Realloc modeling was very poor in terms of variable and structure naming, as
well as documentation, so I renamed some of them and added much needed docs.
* Moved function IdentifierInfos to a separate struct, and moved isMemFunction,
isCMemFunction adn isStandardNewDelete inside it. This makes the patch affect
quite a lot of lines, should I extract it to a separate one?
* Moved MallocBugVisitor out of MallocChecker.
* Preferred switches to long else-if branches in some places.
* Neatly organized some RUN: lines.
Differential Revision: https://reviews.llvm.org/D54823
llvm-svn: 349281
ClangCheckerRegistry is a very non-obvious, poorly documented, weird concept.
It derives from CheckerRegistry, and is placed in lib/StaticAnalyzer/Frontend,
whereas it's base is located in lib/StaticAnalyzer/Core. It was, from what I can
imagine, used to circumvent the problem that the registry functions of the
checkers are located in the clangStaticAnalyzerCheckers library, but that
library depends on clangStaticAnalyzerCore. However, clangStaticAnalyzerFrontend
depends on both of those libraries.
One can make the observation however, that CheckerRegistry has no place in Core,
it isn't used there at all! The only place where it is used is Frontend, which
is where it ultimately belongs.
This move implies that since
include/clang/StaticAnalyzer/Checkers/ClangCheckers.h only contained a single function:
class CheckerRegistry;
void registerBuiltinCheckers(CheckerRegistry ®istry);
it had to re purposed, as CheckerRegistry is no longer available to
clangStaticAnalyzerCheckers. It was renamed to BuiltinCheckerRegistration.h,
which actually describes it a lot better -- it does not contain the registration
functions for checkers, but only those generated by the tblgen files.
Differential Revision: https://reviews.llvm.org/D54436
llvm-svn: 349275
In earlier patches regarding AnalyzerOptions, a lot of effort went into
gathering all config options, and changing the interface so that potential
misuse can be eliminited.
Up until this point, AnalyzerOptions only evaluated an option when it was
querried. For example, if we had a "-no-false-positives" flag, AnalyzerOptions
would store an Optional field for it that would be None up until somewhere in
the code until the flag's getter function is called.
However, now that we're confident that we've gathered all configs, we can
evaluate off of them before analysis, so we can emit a error on invalid input
even if that prticular flag will not matter in that particular run of the
analyzer. Another very big benefit of this is that debug.ConfigDumper will now
show the value of all configs every single time.
Also, almost all options related class have a similar interface, so uniformity
is also a benefit.
The implementation for errors on invalid input will be commited shorty.
Differential Revision: https://reviews.llvm.org/D53692
llvm-svn: 348031
Don't generate a checker-tagged node unconditionally on the first
checkDeadSymbols callback when no pointers are tracked.
This is a tiny performance optimization; it may change the behavior slightly
by making Static Analyzer bail out on max-nodes one node later (which is good)
but any test would either break for no good reason or become useless
every time someone sneezes.
Differential Revision: https://reviews.llvm.org/D54013
llvm-svn: 347955
It's an old bug that consists in stale references to symbols remaining in the
GDM if they disappear from other program state sections as a result of any
operation that isn't the actual dead symbol collection. The most common example
here is:
FILE *fp = fopen("myfile.txt", "w");
fp = 0; // leak of file descriptor
In this example the leak were not detected previously because the symbol
disappears from the public part of the program state due to evaluating
the assignment. For that reason the checker never receives a notification
that the symbol is dead, and never reports a leak.
This patch not only causes leak false negatives, but also a number of other
problems, including false positives on some checkers.
What's worse, even though the program state contains a finite number of symbols,
the set of symbols that dies is potentially infinite. This means that is
impossible to compute the set of all dead symbols to pass off to the checkers
for cleaning up their part of the GDM.
No longer compute the dead set at all. Disallow iterating over dead symbols.
Disallow querying if any symbols are dead. Remove the API for marking symbols
as dead, as it is no longer necessary. Update checkers accordingly.
Differential Revision: https://reviews.llvm.org/D18860
llvm-svn: 347953
One of the reasons why AnalyzerOptions is so chaotic is that options can be
retrieved from the command line whenever and wherever. This allowed for some
options to be forgotten for a looooooong time. Have you ever heard of
"region-store-small-struct-limit"? In order to prevent this in the future, I'm
proposing to restrict AnalyzerOptions' interface so that only checker options
can be retrieved without special getters. I would like to make every option be
accessible only through a getter, but checkers from plugins are a thing, so I'll
have to figure something out for that.
This also forces developers who'd like to add a new option to register it
properly in the .def file.
This is done by
* making the third checker pointer parameter non-optional, and checked by an
assert to be non-null.
* I added new, but private non-checkers option initializers, meant only for
internal use,
* Renamed these methods accordingly (mind the consistent name for once with
getBooleanOption!):
- getOptionAsString -> getCheckerStringOption,
- getOptionAsInteger -> getCheckerIntegerOption
* The 3 functions meant for initializing data members (with the not very
descriptive getBooleanOption, getOptionAsString and getOptionAsUInt names)
were renamed to be overloads of the getAndInitOption function name.
* All options were in some way retrieved via getCheckerOption. I removed it, and
moved the logic to getStringOption and getCheckerStringOption. This did cause
some code duplication, but that's the only way I could do it, now that checker
and non-checker options are separated. Note that the non-checker version
inserts the new option to the ConfigTable with the default value, but the
checker version only attempts to find already existing entries. This is how
it always worked, but this is clunky and I might end reworking that too, so we
can eventually get a ConfigTable that contains the entire configuration of the
analyzer.
Differential Revision: https://reviews.llvm.org/D53483
llvm-svn: 346113
MallocChecker no longer thinks that operator delete() that accepts the size of
the object to delete (available since C++14 or under -fsized-deallocation)
is some weird user-defined operator. Instead, it handles it like normal delete.
Additionally, it exposes a regression in NewDelete-intersections.mm's
testStandardPlacementNewAfterDelete() test, where the diagnostic is delayed
from before the call of placement new into the code of placement new
in the header. This happens because the check for pass-into-function-after-free
for placement arguments is located in checkNewAllocator(), which happens after
the allocator is inlined, which is too late. Move this use-after-free check
into checkPreCall instead, where it works automagically because the guard
that prevents it from working is useless and can be removed as well.
This commit causes regressions under -analyzer-config
c++-allocator-inlining=false but this option is essentially unsupported
because the respective feature has been enabled by default quite a while ago.
Differential Revision: https://reviews.llvm.org/D53543
llvm-svn: 345802
For InnerPointerChecker to function properly, both the checker itself
and parts of MallocChecker that handle relevant use-after-free problems
need to be turned on. So far, the latter part has been developed within
MallocChecker's NewDelete sub-checker, often causing warnings to appear
under that name. This patch defines a new CheckKind within MallocChecker
for the inner pointer checking functionality, so that the correct name
is displayed in warnings and in the ExplodedGraph.
Tested on clang-tidy.
Differential Review: https://reviews.llvm.org/D50211
llvm-svn: 339067
Objects local to a function are destroyed right after the statement returning
(part of) them is executed in the analyzer. This patch enables MallocChecker to
warn in these cases.
Differential Revision: https://reviews.llvm.org/D49361
llvm-svn: 338780
According to the standard, pointers referring to the elements of a
`basic_string` may be invalidated if they are used as an argument to
any standard library function taking a reference to non-const
`basic_string` as an argument. This patch makes InnerPointerChecker warn
for these cases.
Differential Revision: https://reviews.llvm.org/D49656
llvm-svn: 338259
StringRef's data() returns a string that may be non-null-terminated.
Switch to using StringRefs from const char pointers in visitor notes
to avoid problems.
llvm-svn: 337474
DanglingInternalBufferChecker.
A pointer referring to the elements of a basic_string may be invalidated
by calling a non-const member function, except operator[], at, front,
back, begin, rbegin, end, and rend. The checker now warns if the pointer
is used after such operations.
Differential Revision: https://reviews.llvm.org/D49360
llvm-svn: 337463
Add a bug visitor to DanglingInternalBufferChecker that places a note
at the point where the dangling pointer was obtained. The visitor is
handed over to MallocChecker and attached to the report there.
Differential Revision: https://reviews.llvm.org/D48522
llvm-svn: 336495
Extend MallocBugVisitor to place a note at the point where objects with
AF_InternalBuffer allocation family are destroyed.
Differential Revision: https://reviews.llvm.org/D48521
llvm-svn: 336489
In the current implementation, we run visitors until the fixed point is
reached.
That is, if a visitor adds another visitor, the currently processed path
is destroyed, all diagnostics is discarded, and it is regenerated again,
until it's no longer modified.
This pattern has a few negative implications:
- This loop does not even guarantee to terminate.
E.g. just imagine two visitors bouncing a diagnostics around.
- Performance-wise, e.g. for sqlite3 all visitors are being re-run at
least 10 times for some bugs.
We have already seen a few reports where it leads to timeouts.
- If we want to add more computationally intense visitors, this will
become worse.
- From architectural standpoint, the current layout requires copying
visitors, which is conceptually wrong, and can be annoying (e.g. no
unique_ptr on visitors allowed).
The proposed change is a much simpler architecture: the outer loop
processes nodes upwards, and whenever the visitor is added it only
processes current nodes and above, thus guaranteeing termination.
Differential Revision: https://reviews.llvm.org/D47856
llvm-svn: 335666
This check will mark raw pointers to C++ standard library container internal
buffers 'released' when the objects themselves are destroyed. Such information
can be used by MallocChecker to warn about use-after-free problems.
In this first version, 'std::basic_string's are supported.
Differential Revision: https://reviews.llvm.org/D47135
llvm-svn: 334348
This is similar to the LLVM change https://reviews.llvm.org/D46290.
We've been running doxygen with the autobrief option for a couple of
years now. This makes the \brief markers into our comments
redundant. Since they are a visual distraction and we don't want to
encourage more \brief markers in new code either, this patch removes
them all.
Patch produced by
for i in $(git grep -l '\@brief'); do perl -pi -e 's/\@brief //g' $i & done
for i in $(git grep -l '\\brief'); do perl -pi -e 's/\\brief //g' $i & done
Differential Revision: https://reviews.llvm.org/D46320
llvm-svn: 331834
The bindDefault() API of the ProgramState allows setting a default value
for reads from memory regions that were not preceded by writes.
It was used for implementing C++ zeroing constructors (i.e. default constructors
that boil down to setting all fields of the object to 0).
Because differences between zeroing consturctors and other forms of default
initialization have been piling up (in particular, zeroing constructors can be
called multiple times over the same object, probably even at the same offset,
requiring a careful and potentially slow cleanup of previous bindings in the
RegionStore), we split the API in two: bindDefaultInitial() for modeling
initial values and bindDefaultZero() for modeling zeroing constructors.
This fixes a few assertion failures from which the investigation originated.
The imperfect protection from both inability of the RegionStore to support
binding extents and lack of information in ASTRecordLayout has been loosened
because it's, well, imperfect, and it is unclear if it fixing more than it
was breaking.
Differential Revision: https://reviews.llvm.org/D46368
llvm-svn: 331561
r326249 wasn't quite enough because we often run out of inlining stack depth
limit and for that reason fail to see the atomics we're looking for.
Add a more straightforward false positive suppression that is based on the name
of the class. I.e. if we're releasing a pointer in a destructor of a "something
shared/intrusive/reference/counting something ptr/pointer something", then any
use-after-free or double-free that occurs later would likely be a false
positive.
rdar://problem/38013606
Differential Revision: https://reviews.llvm.org/D44281
llvm-svn: 328066
The patch fixes a number of bugs related to parameter indexing in
attributes:
* Parameter indices in some attributes (argument_with_type_tag,
pointer_with_type_tag, nonnull, ownership_takes, ownership_holds,
and ownership_returns) are specified in source as one-origin
including any C++ implicit this parameter, were stored as
zero-origin excluding any this parameter, and were erroneously
printing (-ast-print) and confusingly dumping (-ast-dump) as the
stored values.
* For alloc_size, the C++ implicit this parameter was not subtracted
correctly in Sema, leading to assert failures or to silent failures
of __builtin_object_size to compute a value.
* For argument_with_type_tag, pointer_with_type_tag, and
ownership_returns, the C++ implicit this parameter was not added
back to parameter indices in some diagnostics.
This patch fixes the above bugs and aims to prevent similar bugs in
the future by introducing careful mechanisms for handling parameter
indices in attributes. ParamIdx stores a parameter index and is
designed to hide the stored encoding while providing accessors that
require each use (such as printing) to make explicit the encoding that
is needed. Attribute declarations declare parameter index arguments
as [Variadic]ParamIdxArgument, which are exposed as ParamIdx[*]. This
patch rewrites all attribute arguments that are processed by
checkFunctionOrMethodParameterIndex in SemaDeclAttr.cpp to be declared
as [Variadic]ParamIdxArgument. The only exception is xray_log_args's
argument, which is encoded as a count not an index.
Differential Revision: https://reviews.llvm.org/D43248
llvm-svn: 326602
Throw away MallocChecker warnings that occur after releasing a pointer within a
destructor (or its callees) after performing C11 atomic fetch_add or fetch_sub
within that destructor (or its callees).
This is an indication that the destructor's class is likely a
reference-counting pointer. The analyzer is not able to understand that the
original reference count is usually large enough to avoid most use-after-frees.
Even when the smart pointer is a local variable, we still have these false
positives that this patch suppresses, because the analyzer doesn't currently
support atomics well enough.
Differential Revision: https://reviews.llvm.org/D43791
llvm-svn: 326249
Even though most of the inconsistencies in MallocChecker's bug categories were
fixed in r302016, one more was introduced in r301913 which was later missed.
Patch by Henry Wong!
Differential Revision: https://reviews.llvm.org/D43074
llvm-svn: 324680
The callback runs after operator new() and before the construction and allows
the checker to access the casted return value of operator new() (in the
sense of r322780) which is not available in the PostCall callback for the
allocator call.
Update MallocChecker to use the new callback instead of PostStmt<CXXNewExpr>,
which gets called after the constructor.
Differential Revision: https://reviews.llvm.org/D41406
rdar://problem/12180598
llvm-svn: 322787
In most cases using
`N->getState()->getSVal(E, N->getLocationContext())`
is ugly, verbose, and also opens up more surface area for bugs if an
inconsistent location context is used.
This patch introduces a helper on an exploded node, and ensures
consistent usage of either `ExplodedNode::getSVal` or
`CheckContext::getSVal` across the codebase.
As a result, a large number of redundant lines is removed.
Differential Revision: https://reviews.llvm.org/D42155
llvm-svn: 322753
It was written as "Memory Error" in most places and as "Memory error" in a few
other places, however it is the latter that is more consistent with
other categories (such as "Logic error").
rdar://problem/31718115
Differential Revision: https://reviews.llvm.org/D32702
llvm-svn: 302016
This patch adds LocationContext to checkRegionChanges and removes
wantsRegionChangeUpdate as it was unused.
A patch by Krzysztof Wiśniewski!
Differential Revision: https://reviews.llvm.org/D27090
llvm-svn: 291869
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
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
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
The purpose of these changes is to simplify introduction of definition files
for the three hierarchies.
1. For every sub-class C of these classes, its kind in the relevant enumeration
is changed to "CKind" (or C##Kind in preprocessor-ish terms), eg:
MemRegionKind -> MemRegionValKind
RegionValueKind -> SymbolRegionValueKind
CastSymbolKind -> SymbolCastKind
SymIntKind -> SymIntExprKind
2. MemSpaceRegion used to be inconsistently used as both an abstract base and
a particular region. This region class is now an abstract base and no longer
occupies GenericMemSpaceRegionKind. Instead, a new class, CodeSpaceRegion,
is introduced for handling the unique use case for MemSpaceRegion as
"the generic memory space" (when it represents a memory space that holds all
executable code).
3. BEG_ prefixes in memory region kind ranges are renamed to BEGIN_ for
consisitency with symbol kind ranges.
4. FunctionTextRegion and BlockTextRegion are renamed to FunctionCodeRegion and
BlockCodeRegion, respectively. The term 'code' is less jargony than 'text' and
we already refer to BlockTextRegion as a 'code region' in BlockDataRegion.
Differential Revision: http://reviews.llvm.org/D16062
llvm-svn: 257598
The analyzer assumes that system functions will not free memory or modify the
arguments in other ways, so we assume that arguments do not escape when
those are called. However, this may lead to false positive leak errors. For
example, in code like this where the pointers added to the rb_tree are freed
later on:
struct alarm_event *e = calloc(1, sizeof(*e));
<snip>
rb_tree_insert_node(&alarm_tree, e);
Add a heuristic to assume that calls to system functions taking void*
arguments allow for pointer escape.
llvm-svn: 251449
Currently realloc(ptr, 0) is treated as free() which seems to be not correct. C
standard (N1570) establishes equivalent behavior for malloc(0) and realloc(ptr,
0): "7.22.3 Memory management functions calloc, malloc, realloc: If the size of
the space requested is zero, the behavior is implementation-defined: either a
null pointer is returned, or the behavior is as if the size were some nonzero
value, except that the returned pointer shall not be used to access an object."
The patch equalizes the processing of malloc(0) and realloc(ptr,0). The patch
also enables unix.Malloc checker to detect references to zero-allocated memory
returned by realloc(ptr,0) ("Use of zero-allocated memory" warning).
A patch by Антон Ярцев!
Differential Revision: http://reviews.llvm.org/D9040
llvm-svn: 248336
The analyzer trims unnecessary nodes from the exploded graph before reporting
path diagnostics. However, in some cases it can trim all nodes (including the
error node), leading to an assertion failure (see
https://llvm.org/bugs/show_bug.cgi?id=24184).
This commit addresses the issue by adding two new APIs to CheckerContext to
explicitly create error nodes. Unless the client provides a custom tag, these
APIs tag the node with the checker's tag -- preventing it from being trimmed.
The generateErrorNode() method creates a sink error node, while
generateNonFatalErrorNode() creates an error node for a path that should
continue being explored.
The intent is that one of these two methods should be used whenever a checker
creates an error node.
This commit updates the checkers to use these APIs. These APIs
(unlike addTransition() and generateSink()) do not take an explicit Pred node.
This is because there are not any error nodes in the checkers that were created
with an explicit different than the default (the CheckerContext's Pred node).
It also changes generateSink() to require state and pred nodes (previously
these were optional) to reduce confusion.
Additionally, there were several cases where checkers did check whether a
generated node could be null; we now explicitly check for null in these places.
This commit also includes a test case written by Ying Yi as part of
http://reviews.llvm.org/D12163 (that patch originally addressed this issue but
was reverted because it introduced false positive regressions).
Differential Revision: http://reviews.llvm.org/D12780
llvm-svn: 247859
Make the copy/move ctors defaulted in the base class and make the
derived classes final to avoid any intermediate hierarchy slicing if
these types were further derived.
llvm-svn: 244979
(return by value is in ExprEngine::processPointerEscapedOnBind and any
other call to the scanReachableSymbols function template used there)
Protect the special members in the base class to avoid slicing, and make
derived classes final so these special members don't accidentally become
public on an intermediate base which would open up the possibility of
slicing again.
llvm-svn: 244975
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
Artem Dergachev