This commits sets the grounds for more aggressive use after free
checking. We will use the Relinquished sate to denote that someone
else is now responsible for releasing the memory.
llvm-svn: 158850
Specifically, although the bitmap context does not take ownership of the
buffer (unlike CGBitmapContextCreateWithData), the data buffer can be extracted
out of the created CGContextRef. Thus the buffer is not leaked even if its
original pointer goes out of scope, as long as
- the context escapes, or
- it is retrieved via CGBitmapContextGetData and freed.
Actually implementing that logic is beyond the current scope of MallocChecker,
so for now CGBitmapContextCreate goes on our system function exception list.
llvm-svn: 158579
We already didn't track objects that have delegates or callbacks or
objects that are passed through void * "context pointers". It's a
not-uncommon pattern to release the object in its callback, and so
the leak message we give is not very helpful.
llvm-svn: 158532
* Add \brief to produce a summary in the Doxygen output;
* Add missing parameter names to \param commands;
* Fix mismatched parameter names for \param commands;
* Add a parameter name so that the \param has a target.
llvm-svn: 158503
While collections containing nil elements can still be iterated over in an
Objective-C for-in loop, the most common Cocoa collections -- NSArray,
NSDictionary, and NSSet -- cannot contain nil elements. This checker adds
that assumption to the analyzer state.
This was the cause of some minor false positives concerning CFRelease calls
on objects in an NSArray.
llvm-svn: 158319
This has a small hit in the case where only one class is interesting
(NilArgChecker) but is a big improvement when looking for one of several
interesting classes (VariadicMethodTypeChecker), in which the most common
case is that there is no match.
llvm-svn: 158318
to addition.
We should not to warn in case the malloc size argument is an
addition containing 'sizeof' operator - it is common to use the pattern
to pack values of different sizes into a buffer.
Ex:
uint8_t *buffer = (uint8_t*)malloc(dataSize + sizeof(length));
llvm-svn: 158219
Add a concept of symbolic memory region belonging to heap memory space.
When comparing symbolic regions allocated on the heap, assume that they
do not alias.
Use symbolic heap region to suppress a common false positive pattern in
the malloc checker, in code that relies on malloc not returning the
memory aliased to other malloc allocations, stack.
llvm-svn: 158136
In addition, I've made the pointer and reference typedef 'void' rather than T*
just so they can't get misused. I would've omitted them entirely but
std::distance likes them to be there even if it doesn't use them.
This rolls back r155808 and r155869.
Review by Doug Gregor incorporating feedback from Chandler Carruth.
llvm-svn: 158104
improved the pruning heuristics. The current heuristics are pretty good, but they make diagnostics
for uninitialized variables warnings particularly useless in some cases.
llvm-svn: 157734
The new debug.ExprInspection checker looks for calls to clang_analyzer_eval,
and emits a warning of TRUE, FALSE, or UNKNOWN (or UNDEFINED) based on the
constrained value of its (boolean) argument. It does not modify the analysis
state though the conditions tested can result in branches (e.g. through the
use of short-circuit operators).
llvm-svn: 156919
We check the address of the last element accessed, but with 0 calculating that
address results in element -1. This patch bails out early (and avoids a bunch
of other work at that).
Fixes PR12807.
llvm-svn: 156769
We report a leak at a point a leaked variable is no longer accessible.
The statement that happens to be at that point is not relevant to the
leak diagnostic and, thus, should not be highlighted.
radar://11178519
llvm-svn: 156530
don't reason about.
Self is just like a local variable in init methods, so it can be
assigned anything like result of static functions, other methods ... So
to suppress false positives that result in such cases, stop tracking the
checker-specific state after self is being assigned to (unless the
value is't being assigned to is either self or conforms to our rules).
This change does not invalidate any existing regression tests.
llvm-svn: 156420
specifically checks for equality to null.
Enforcing this general practice, which keeps the analyzer less
noisy, in the CString Checker. This change suppresses "Assigned value is
garbage or undefined" warning in the added test case.
llvm-svn: 156085
filter_decl_iterator had a weird mismatch where both op* and op-> returned T*
making it difficult to generalize this filtering behavior into a reusable
library of any kind.
This change errs on the side of value, making op-> return T* and op* return
T&.
(reviewed by Richard Smith)
llvm-svn: 155808
(Applied changes to CStringAPI, Malloc, and Taint.)
This might almost never happen, but we should not crash even if it does.
This fixes a crash on the internal analyzer buildbot, where postgresql's
configure was redefining memmove (radar://11219852).
llvm-svn: 154451
we use the same Expr* as the one being currently visited. This is preparation for transitioning to having
ProgramPoints refer to CFGStmts.
This required a bit of trickery. We wish to keep the old Expr* bindings in the Environment intact,
as plenty of logic relies on it and there is no reason to change it, but we sometimes want the Stmt* for
the ProgramPoint to be different than the Expr* being used for bindings. This requires adding an extra
argument for some functions (e.g., evalLocation). This looks a bit strange for some clients, but
it will look a lot cleaner when were start using CFGStmt* in the appropriate places.
As some fallout, the diagnostics arrows are a bit difference, since some of the node locations have changed.
I have audited these, and they look reasonable.
llvm-svn: 154214
consolidate some commonly used category strings into global references (more of this can be done, I just did a few).
Fixes <rdar://problem/11191537>.
llvm-svn: 154121
Fixes a false positive (radar://11152419). The current solution of
adding the info into 3 places is quite ugly. Pending a generic pointer
escapes callback.
llvm-svn: 153731
Report root function name with exhausted block diagnostic.
Also, use stack frames, not just any location context when checking if
the basic block is in the same context.
llvm-svn: 153532
assigned to a struct. This is fallout from inlining results, which expose
far more patterns where people stuff CF objects into structs and pass them
around (and we can reason about it). The problem is that we don't have
a general way to detect when values have escaped, so as an intermediate step
we need to eagerly prune out such tracking.
Fixes <rdar://problem/11104566>.
llvm-svn: 153489
This required adding a change count token to BugReport, but also allowed us to ditch ImmutableList as the BugReporterVisitor data type.
Also, remove the hack from MallocChecker, now that visitors appear in the opposite order. This is not exactly a fix, but the common case -- custom diagnostics after generic ones -- is now the default behavior.
llvm-svn: 153369
Specifically, we use the last store of the leaked symbol in the leak diagnostic.
(No support for struct fields since the malloc checker doesn't track those
yet.)
+ Infrastructure to track the regions used in store evaluations.
This approach is more precise than iterating the store to
obtain the region bound to the symbol, which is used in RetainCount
checker. The region corresponds to what is uttered in the code in the
last store and we do not rely on the store implementation to support
this functionality.
llvm-svn: 153212
This is accomplished by calling markInteresting /during/ path diagnostic generation, and as such relies on deterministic ordering of BugReporterVisitors -- namely, that BugReporterVisitors are run in /reverse/ order from how they are added. (Right now that's a consequence of storing visitors in an ImmutableList, where new items are added to the front.) It's a little hacky, but it works for now.
I think this is the best we can do without storing the relation between the old and new symbols, and that would be a hit whether or not there ends up being an error.
llvm-svn: 153010
I tried to test the effects of this change on memory usage and run time, but what I saw on retain-release.m was indistinguishable from noise (debug and release builds). Even so, some caveman profiling showed 101 cache hits that we would have generated new summaries for before (i.e. not default or stop summaries), and the more code we analyze, the more memory we should save.
Maybe we should have a standard project for benchmarking the retain count checker's memory and time?
llvm-svn: 153007
The cocoa::deriveNamingConventions helper is just using method families anyway now, and the way RetainSummaryTemplate works means we're allocating an extra summary for every method with a relevant family.
Also, fix RetainSummaryTemplate to do the right thing w/r/t annotating an /existing/ summary. This was probably the real cause of <rdar://problem/10824732> and the fix in r152448.
llvm-svn: 152998
The symbol-aware stack hint combines the checker-provided message
with the information about how the symbol was passed to the callee: as
a parameter or a return value.
For malloc, the generated messages look like this :
"Returning from 'foo'; released memory via 1st parameter"
"Returning from 'foo'; allocated memory via 1st parameter"
"Returning from 'foo'; allocated memory returned"
"Returning from 'foo'; reallocation of 1st parameter failed"
(We are yet to handle cases when the symbol is a field in a struct or
an array element.)
llvm-svn: 152962
BugVisitor DiagnosticPieces.
When checkers create a DiagnosticPieceEvent, they can supply an extra
string, which will be concatenated with the call exit message for every
call on the stack between the diagnostic event and the final bug report.
(This is a simple version, which could be/will be further enhanced.)
For example, this is used in Malloc checker to produce the ",
which allocated memory" in the following example:
static char *malloc_wrapper() { // 2. Entered call from 'use'
return malloc(12); // 3. Memory is allocated
}
void use() {
char *v;
v = malloc_wrapper(); // 1. Calling 'malloc_wrappers'
// 4. Returning from 'malloc_wrapper', which allocated memory
} // 5. Memory is never released; potential
memory leak
llvm-svn: 152837
track whether the referenced declaration comes from an enclosing
local context. I'm amenable to suggestions about the exact meaning
of this bit.
llvm-svn: 152491
Essentially, a bug centers around a story for various symbols and regions. We should only include
the path diagnostic events that relate to those symbols and regions.
The pruning is done by associating a set of interesting symbols and regions with a BugReporter, which
can be modified at BugReport creation or by BugReporterVisitors.
This patch reduces the diagnostics emitted in several of our test cases. I've vetted these as
having desired behavior. The only regression is a missing null check diagnostic for the return
value of realloc() in test/Analysis/malloc-plist.c. This will require some investigation to fix,
and I have added a FIXME to the test case.
llvm-svn: 152361
The final graph contains a single root node, which is a parent of all externally available functions(and 'main'). As well as a list of Parentless/Unreachable functions, which are either truly unreachable or are unreachable due to our analyses imprecision.
The analyzer checkers debug.DumpCallGraph or debug.ViewGraph can be used to look at the produced graph.
Currently, the graph is not very precise, for example, it entirely skips edges resulted from ObjC method calls.
llvm-svn: 152272
funopen, setvbuf.
Teach the checker and the engine about these APIs to resolve malloc
false positives. As I am adding more of these APIs, it is clear that all
this should be factored out into a separate callback (for example,
region escapes). Malloc, KeyChainAPI and RetainRelease checkers could
all use it.
llvm-svn: 151737
When allocated buffer is passed to CF/NS..NoCopy functions, the
ownership is transfered unless the deallocator argument is set to
'kCFAllocatorNull'.
llvm-svn: 151608
Assume none of the ObjC messages defined in system headers free memory,
except for the ones containing 'freeWhenDone' selector. Currently, just
assume that the region escapes to the messages with 'freeWhenDone'
(ideally, we want to treat it as 'free()').
For now, always assume that regions escape when passed to C++ methods.
llvm-svn: 151410
When we find two leak reports with the same allocation site, report only
one of them.
Provide a helper method to BugReporter to facilitate this.
llvm-svn: 151287
Make this call an exception in ExprEngine::invalidateArguments:
'int pthread_setspecific(ptheread_key k, const void *)' stores
a value into thread local storage. The value can later be retrieved
with 'void *ptheread_getspecific(pthread_key)'. So even thought the
parameter is 'const void *', the region escapes through the
call.
(Here we just blacklist the call in the ExprEngine's default
logic. Another option would be to add a checker which evaluates
the call and triggers the call to invalidate regions.)
Teach the Malloc Checker, which treats all system calls as safe about
the API.
llvm-svn: 151220
- We should not evaluate strdup in the Malloc Checker, it's the job of
CString checker, so just update the RefState to reflect allocated
memory.
- Refactor to reduce LOC: remove some wrapper auxiliary functions, make
all functions return the state and add the transition in one place
(instead of in each auxiliary function).
llvm-svn: 151188
it aware of CString APIs that return the input parameter.
Malloc Checker needs to know how the 'strcpy' function is
evaluated. Introduce the dependency on CStringChecker for that.
CStringChecker knows all about these APIs.
Addresses radar://10864450
llvm-svn: 150846
We are not properly handling the memory regions that escape into struct
fields, which led to a bunch of false positives. Be conservative here
and give up when a pointer escapes into a struct.
llvm-svn: 150658
(In response of Ted's review of r150112.)
This moves the logic which checked if a symbol escapes through a
parameter to invalidateRegionCallback (instead of post CallExpr visit.)
To accommodate the change, added a CallOrObjCMessage parameter to
checkRegionChanges callback.
llvm-svn: 150513
in realloc map.
If there is no dependency, the reallocated ptr will get garbage
collected before we know that realloc failed, which would lead us to
missing a memory leak warning.
Also added new test cases, which we can handle now.
Plus minor cleanups.
llvm-svn: 150446
1) Support the case when realloc fails to reduce False Positives. (We
essentially need to restore the state of the pointer being reallocated.)
2) Realloc behaves differently under special conditions (from pointer is
null, size is 0). When detecting these cases, we should consider
under-constrained states (size might or might not be 0). The
old version handled this in a very hacky way. The code did not
differentiate between definite and possible (no consideration for
under-constrained states). Further, after processing each special case,
the realloc processing function did not return but chained to the next
special case processing. So you could end up in an execution in which
you first see the states in which size is 0 and realloc ~ free(),
followed by the states corresponding to size is not 0 followed by the
evaluation of the regular realloc behavior.
llvm-svn: 150402
memory.
(As per one test case, the existing checker thought that this could
cause a lot of false positives - not sure if that's valid, to be
verified.)
llvm-svn: 150313
which allows values to escape through unknown calls.
Assumes all calls but the malloc family are unknown.
Also, catch a use-after-free when a pointer is passed to a
function after a call to free (previously, you had to explicitly
dereference the pointer value).
llvm-svn: 150112
optimistic.
TODO: actually implement the pessimistic version of the checker. Ex: it
needs to assume that any function that takes a pointer might free it.
The optimistic version relies on annotations to tell us which functions
can free the pointer.
llvm-svn: 150111
This seems to negatively affect compile time onsome ObjC tests
(which use a lot of partial diagnostics I assume). I have to come
up with a way to keep them inline without including Diagnostic.h
everywhere. Now adding a new diagnostic requires a full rebuild
of e.g. the static analyzer which doesn't even use those diagnostics.
This reverts commit 6496bd10dc3a6d5e3266348f08b6e35f8184bc99.
This reverts commit 7af19b817ba964ac560b50c1ed6183235f699789.
This reverts commit fdd15602a42bbe26185978ef1e17019f6d969aa7.
This reverts commit 00bd44d5677783527d7517c1ffe45e4d75a0f56f.
This reverts commit ef9b60ffed980864a8db26ad30344be429e58ff5.
llvm-svn: 150006
Fix all the files that depended on transitive includes of Diagnostic.h.
With this patch in place changing a diagnostic no longer requires a full rebuild of the StaticAnalyzer.
llvm-svn: 149781
the the code like this (due to x and &x being the same value but
different size):
void* x[] = { ptr1, ptr2, ptr3 };
CFArrayCreate(NULL, (const void **) &x, count, NULL);
llvm-svn: 149579
At this point this is largely cosmetic, but it opens the door to replace
ProgramStateRef with a smart pointer that more eagerly acts in the role
of reclaiming unused ProgramState objects.
llvm-svn: 149081
using CFArrayCreate & family.
Specifically, CFArrayCreate's input should be:
'A C array of the pointer-sized values to be in the new array.'
(radar://10717339)
llvm-svn: 149008
Also, slightly modify the diagnostic message in ArrayBound and DivZero (still use 'taint', which might not mean much to the user, but plan on changing it later).
llvm-svn: 148626
size (Ex: in malloc, memcpy, strncpy..)
(Maybe some of this could migrate to the CString checker. One issue
with that is that we might want to separate security issues from
regular API misuse.)
llvm-svn: 148371
To simplify the process:
Refactor taint generation checker to simplify passing the
information on which arguments need to be tainted from pre to post
visit.
Todo: We need to factor out the code that sema is using to identify the
string and memcpy functions and use it here and in the CString checker.
llvm-svn: 148010
the common *alloc functions as well as a few tiny wibbles (adds a note
to CWE/CERT advisory numbers in the bug output, and fixes a couple
80-column-wide violations.)"
Patch by Austin Seipp!
llvm-svn: 147931
We already have a more conservative check in the compiler (if the
format string is not a literal, we warn). Still adding it here for
completeness and since this check is stronger - only triggered if the
format string is tainted.
llvm-svn: 147714
(Stmt*,LocationContext*) pairs to SVals instead of Stmt* to SVals.
This is needed to support basic IPA via inlining. Without this, we cannot tell
if a Stmt* binding is part of the current analysis scope (StackFrameContext) or
part of a parent context.
This change introduces an uglification of the use of getSVal(), and thus takes
two steps forward and one step back. There are also potential performance implications
of enlarging the Environment. Both can be addressed going forward by refactoring the
APIs and optimizing the internal representation of Environment. This patch
mainly introduces the functionality upon when we want to build upon (and clean up).
llvm-svn: 147688
as a result of a call.
Problem:
Global variables, which come in from system libraries should not be
invalidated by all calls. Also, non-system globals should not be
invalidated by system calls.
Solution:
The following solution to invalidation of globals seems flexible enough
for taint (does not invalidate stdin) and should not lead to too
many false positives. We split globals into 3 classes:
* immutable - values are preserved by calls (unless the specific
global is passed in as a parameter):
A : Most system globals and const scalars
* invalidated by functions defined in system headers:
B: errno
* invalidated by all other functions (note, these functions may in
turn contain system calls):
B: errno
C: all other globals (which are not in A nor B)
llvm-svn: 147569
Check if the input parameters are tainted (or point to tainted data) on
a checkPreStmt<CallExpr>. If the output should be tainted, record it in
the state. On post visit (checkPostStmt<CallExpr>), use the state to
make decisions (in addition to the existing logic). Use this logic for
atoi and fscanf.
llvm-svn: 146793
Some of the test cases do not currently work because the analyzer core
does not seem to call checkers for pre/post DeclRefExpr visits.
(Opened radar://10573500. To be fixed later on.)
llvm-svn: 146536
We are now often generating expressions even if the solver is not known to be able to simplify it. This is another cleanup of the existing code, where the rest of the analyzer and checkers should not base their logic on knowing ahead of the time what the solver can reason about.
In this case, CStringChecker is performing a check for overflow of 'left+right' operation. The overflow can be checked with either 'maxVal-left' or 'maxVal-right'. Previously, the decision was based on whether the expresion evaluated to undef or not. With this patch, we check if one of the arguments is a constant, in which case we know that 'maxVal-const' is easily simplified. (Another option is to use canReasonAbout() method of the solver here, however, it's currently is protected.)
This patch also contains 2 small bug fixes:
- swap the order of operators inside SValBuilder::makeGenericVal.
- handle a case when AddeVal is unknown in GenericTaintChecker::getPointedToSymbol.
llvm-svn: 146343
between the casted type of the return value of a malloc/calloc/realloc
call and the operand of any sizeof expressions contained within
its argument(s).
llvm-svn: 146144
We trigger an error if free is called after a possibly failed allocation. Do not trigger the error if we know that the buffer is not null.
llvm-svn: 145584
We are getting name of the called function or it's declaration in a few checkers. Refactor them to use the helper function in the CheckerContext.
llvm-svn: 145576
explicit template specializations (which represent actual functions somebody wrote).
Along the way, refactor some other code which similarly cares about whether or
not they are looking at a template instantiation.
llvm-svn: 145547
Change the ArrayBoundCheckerV2 to be more aggressive in reporting buffer overflows
when the offset is tainted. Previously, we did not report bugs when the state was
underconstrained (not enough information about the bound to determine if there is
an overflow) to avoid false positives. However, if we know that the buffer
offset is tainted - comes in from the user space and can be anything, we should
report it as a bug.
+ The very first example of us catching a taint related bug.
This is the only example we can currently handle. More to come...
llvm-svn: 144826
Analysis by Ted:
"
if (stateZero && !stateNotZero) {
is checking to see if:
(A) "it is possible for the value to be zero" (stateZero)
AND
(B) "it is not possible for the value to be non-zero" (!stateNotZero)
That said, the only way for both B to be true AND A to be false is if the path is completely infeasible by the time we reach the divide-by-zero check. For the most part (all cases?), such cases should automatically get pruned out at branches (i.e., an infeasible path gets dropped), which is the case in our tests. So the question is whether or not such an infeasible path might not get dropped earlier? I can't envision any right now.
Indeed, the rest of the checker assumes that if the bug condition didn't fire then 'stateNotZero' is non-NULL:
C.addTransition(stateNotZero);
"
llvm-svn: 144114
A step toward making sure that diagnostics report should only
be generated though the CheckerContext and not though BugReporter
or ExprEngine directly.
llvm-svn: 142947
Remove dead members/parameters: ProgramState, respondsToCallback, autoTransition.
Remove addTransition method since it's the same as generateNode. Maybe we should
rename generateNode to genTransition (since a transition is always automatically
generated)?
llvm-svn: 142946
Get rid of the EndOfPathBuilder completely.
Use the generic NodeBuilder to generate nodes.
Enqueue the end of path frontier explicitly.
llvm-svn: 142943
NodeBuilder should not assume it's dealing with a single predecessor. Remove predecessor getters. Modify the BranchNodeBuilder to not be responsible for doing auto-transitions (which depend on a predecessor).
llvm-svn: 142453
Take advantage of the new builders for branch processing. As part of this change pass generic NodeBuilder (instead of BranchNodeBuilder) to the BranchCondition callback and remove the unused methods form BranchBuilder.
llvm-svn: 142448
Currently we have a bunch of different node builders which provide some common
functionality but are difficult to refactor. Each builder generates nodes of
different kinds and calculates the frontier nodes, which should be propagated
to the next step (after the builder dies).
Introduce a new NodeBuilder which provides very basic node generation facilities
but takes care of the second problem. The idea is that all the other builders
will eventually use it. Use this builder in CheckerContext instead of
StmtNodeBuilder (the way the frontier is propagated to the StmtBuilder
is a hack and will be removed later on).
llvm-svn: 142443
- Remodel Expr::EvaluateAsInt to behave like the other EvaluateAs* functions,
and add Expr::EvaluateKnownConstInt to capture the current fold-or-assert
behaviour.
- Factor out evaluation of bitfield bit widths.
- Fix a few places which would evaluate an expression twice: once to determine
whether it is a constant expression, then again to get the value.
llvm-svn: 141561
- Remove unused FindUndefExpr::ProgramStateManager.
- The Condition parameter of the callback is the terminator of the block, no need to retrieve it again.
llvm-svn: 141027
Instead of always storing all source locations for the selector identifiers
we check whether all the identifiers are in a "standard" position; "standard" position is
-Immediately before the arguments: -(id)first:(int)x second:(int)y;
-With a space between the arguments: -(id)first: (int)x second: (int)y;
-For nullary selectors, immediately before ';': -(void)release;
In such cases we infer the locations instead of storing them.
llvm-svn: 140989
to take a FunctionDecl* instead of an llvm::StringRef. Eventually
we might push more logic in there, like using slightly different
conventions for C++ methods.
Also, fix a bug where 'copy' and 'create' were being caught in
non-camel-cased strings. We want copyFoo and CopyFoo and XCopy
but not Xcopy or xcopy.
llvm-svn: 140911
- Fix a fixme and move the logic of creating a PathDiagnosticLocation corresponding to a ProgramPoint into a PathDiagnosticLocation constructor.
- Rename PathDiagnosticLocation::create to differentiate from the added constructor.
llvm-svn: 139825
- Modify all PathDiagnosticLocation constructors that take Stmt to also requre LocationContext.
- Add a constructor which should be used in case there is no valid statement/location (it will grab the location of the enclosing function).
llvm-svn: 139763
language options. Use that .def file to declare the LangOptions class
and initialize all of its members, eliminating a source of annoying
initialization bugs.
AST serialization changes are next up.
llvm-svn: 139605
Remove TransferFuncs from ExprEngine and AnalysisConsumer.
Demote RetainReleaseChecker to a regular checker, and give it the name osx.cocoa.RetainCount (class name change coming shortly). Update tests accordingly.
llvm-svn: 138998
builtin types (When requested). This is another step toward making
ASTUnit build the ASTContext as needed when loading an AST file,
rather than doing so after the fact. No actual functionality change (yet).
llvm-svn: 138985
Also, allow CallOrObjCMessage to wrap a CXXConstructExpr as well.
Finally, this allows us to remove the clunky whitelisting system from CFRefCount/RetainReleaseChecker. Slight regression due to CXXNewExprs not yet being handled in post-statement callbacks (PR forthcoming).
llvm-svn: 138716
Also convert stack-addr-ps.cpp to use the analyzer instead of just Sema, now
that it doesn't crash, and extract the stack-block test into another file since
it errors, and that prevents the analyzer from running.
llvm-svn: 138613
1) Create a header file to expose the predefined visitors. And move the parent(BugReporterVisitor) there as well.
2) Remove the registerXXXVisitor functions - the Visitor constructors/getters can be used now to create the object. One exception is registerVarDeclsLastStore(), which registers more then one visitor, so make it static member of FindLastStoreBRVisitor.
3) Modify all the checkers to use the new API.
llvm-svn: 138126
Having a notion of an actual ProgramPointTag will aid in introspection of the analyzer's behavior.
For example, the GraphViz output of the analyzer will pretty-print the tags in a useful manner.
llvm-svn: 137529
Report errors earlier: on checkDeadSymbols() and clear the state after the symbol we are tracking goes out of scope.
Also, perform lazy error checking. Instead of forcing the paths to be split depending one the return value of the allocator, make the return symbol depend on the allocated data symbol, which prolongs its life span to the time when the allocated data symbol becomes dead.
llvm-svn: 137523
The motivation of this large change is to drastically simplify the logic in ExprEngine going forward.
Some fallout is that the output of some BugReporterVisitors is not as accurate as before; those will
need to be fixed over time. There is also some possible performance regression as RemoveDeadBindings
will be called frequently; this can also be improved over time.
llvm-svn: 136419
MaterializeTemporaryExpr captures a reference binding to a temporary
value, making explicit that the temporary value (a prvalue) needs to
be materialized into memory so that its address can be used. The
intended AST invariant here is that a reference will always bind to a
glvalue, and MaterializeTemporaryExpr will be used to convert prvalues
into glvalues for that binding to happen. For example, given
const int& r = 1.0;
The initializer of "r" will be a MaterializeTemporaryExpr whose
subexpression is an implicit conversion from the double literal "1.0"
to an integer value.
IR generation benefits most from this new node, since it was
previously guessing (badly) when to materialize temporaries for the
purposes of reference binding. There are likely more refactoring and
cleanups we could perform there, but the introduction of
MaterializeTemporaryExpr fixes PR9565, a case where IR generation
would effectively bind a const reference directly to a bitfield in a
struct. Addresses <rdar://problem/9552231>.
llvm-svn: 133521
Language-design credit goes to a lot of people, but I particularly want
to single out Blaine Garst and Patrick Beard for their contributions.
Compiler implementation credit goes to Argyrios, Doug, Fariborz, and myself,
in no particular order.
llvm-svn: 133103
- (bounded copies) Be more conservative about how much is being copied.
- (str(n)cat) If we can't compute the exact final length of an append operation, we can still lower-bound it.
- (stpcpy) Fix the conjured return value at the end to actually be returned.
This requires these supporting changes:
- C string metadata symbols are still live even when buried in a SymExpr.
- "Hypothetical" C string lengths, to represent a value that /will/ be passed to setCStringLength() if all goes well. (The idea is to allow for temporary constrainable symbols that may end up becoming permanent.)
- The 'checkAdditionOverflow' helper makes sure that the two strings being appended in a strcat don't overflow size_t. This should never *actually* happen; the real effect is to keep the final string length from "wrapping around" in the constraint manager.
This doesn't actually test the "bounded" operations (strncpy and strncat) because they can leave strings unterminated. Next on the list!
llvm-svn: 133046
- New isDefined() function checks for deletedness
- isThisDeclarationADefinition checks for deletedness
- New doesThisDeclarationHaveABody() does what
isThisDeclarationADefinition() used to do
- The IsDeleted bit is not propagated across redeclarations
- isDeleted() now checks the canoncial declaration
- New isDeletedAsWritten() does what it says on the tin.
- isUserProvided() now correct (thanks Richard!)
This fixes the bug that we weren't catching
void foo() = delete;
void foo() {}
as being a redefinition.
llvm-svn: 131013
Validates inputs are not NULL, checks for overlapping strings, concatenates the strings checking for buffer overflow, sets the length of the destination string to the sum of the s1 length and the s2 length, binds the return value to the s1 value.
llvm-svn: 129215
Models mempcpy() so that if length is NULL the destination pointer is returned. Otherwise, the source and destination are confirmed not to be NULL and not overlapping. Finally the copy is validated to not cause a buffer overrun and the return value is bound to the address of the byte after the last byte copied.
llvm-svn: 128677
This rename serves two purposes:
- It reflects the actual functionality of this analysis.
- We will have more than one reachability analysis.
llvm-svn: 127930
conventional categories into Basic and AST. Update the self-init checker
to use this logic; CFRefCountChecker is complicated enough that I didn't
want to touch it.
llvm-svn: 126817
They cooperate in that NSErrorChecker listens for ImplicitNullDerefEvent events that
DereferenceChecker can dispatch.
ImplicitNullDerefEvent is when we dereferenced a location that may be null.
llvm-svn: 126659
For example, if 'core.experimental.UnreachableCode' is hidden, it should not be enabled with 'core.experimental'.
Note that this requires llvm commit r126436.
llvm-svn: 126439
-Introduce EndOfFunctionNodeBuilder::withCheckerTag to allow it be "specialized" with a
checker tag and not require the checkers to pass a tag.
-For EndOfFunctionNodeBuilder::generateNode, reverse the order of tag/P parameters since
there are actual calls that assume the second parameter is ExplodedNode.
llvm-svn: 126332
-In general, don't have the BugReporter deleting BugTypes, BugTypes will eventually become owned by checkers
and outlive the BugReporter. In the meantime, there will be some leaks since some checkers assume that
the BugTypes they create will be destroyed by the BugReporter.
-Have BugReporter::EmitBasicReport create BugTypes that are reused if the same name & category strings
are passed to EmitBasicReport. These BugTypes are owned and destroyed by the BugReporter.
This allows bugs reported through EmitBasicReport to be coalesced.
-Remove the llvm::FoldingSet<BugReportEquivClass> from BugType and move it into the BugReporter.
For uniquing BugReportEquivClass also use the BugType* so that we can iterate over all of them using only one set.
llvm-svn: 126272
-Migrate ObjCSelfInitChecker to CheckerV2. In the process remove the 'preCallSelfFlags' field
from the checker class and use GRState for storing that info.
-Get ExprEngine to start delegating checker running to CheckerManager.
llvm-svn: 126229
The relative checker package is 'debug':
'-dump-live-variables' is replaced by '-analyzer-checker=debug.DumpLiveVars'
'-cfg-view' is replaced by '-analyzer-checker=debug.ViewCFG'
'-cfg-dump' is replaced by '-analyzer-checker=debug.DumpCFG'
llvm-svn: 125780
-Introduce CheckerV2, a set of templates for convenient declaration & registration of checkers.
Currently useful just for checkers working on the AST not the path-sensitive ones.
-Enhance CheckerManager to actually collect the checkers and turn it into the entry point for
running the checkers.
-Use the new mechanism for the LLVMConventionsChecker.
llvm-svn: 125778
class and to bind the shared value using OpaqueValueExpr. This fixes an
unnoticed problem with deserialization of these expressions where the
deserialized form would lose the vital pointer-equality trait; or rather,
it fixes it because this patch also does the right thing for deserializing
OVEs.
Change OVEs to not be a "temporary object" in the sense that copy elision is
permitted.
This new representation is not totally unawkward to work with, but I think
that's really part and parcel with the semantics we're modelling here. In
particular, it's much easier to fix things like the copy elision bug and to
make the CFG look right.
I've tried to update the analyzer to deal with this in at least some
obvious cases, and I think we get a much better CFG out, but the printing
of OpaqueValueExprs probably needs some work.
llvm-svn: 125744
LabelDecl and LabelStmt. There is a 1-1 correspondence between the
two, but this simplifies a bunch of code by itself. This is because
labels are the only place where we previously had references to random
other statements, causing grief for AST serialization and other stuff.
This does cause one regression (attr(unused) doesn't silence unused
label warnings) which I'll address next.
This does fix some minor bugs:
1. "The only valid attribute " diagnostic was capitalized.
2. Various diagnostics printed as ''labelname'' instead of 'labelname'
3. This reduces duplication of label checking between functions and blocks.
Review appreciated, particularly for the cindex and template bits.
llvm-svn: 125733
CStringChecker
ChrootChecker
MallocChecker
PthreadLockChecker
StreamChecker
UnreachableCodeChecker
MallocChecker creates implicit dependencies between checkers and needs to be handled differently.
llvm-svn: 125598
-Update tablegen files for checkers, use the tablegen class name for the checker class name.
-Update ClangSACheckersProvider to not look into hidden checker packages.
llvm-svn: 125560
StackAddrLeakChecker
ObjCAtSyncChecker
UnixAPIChecker
MacOSXAPIChecker
The rest have/create implicit dependencies between checkers and need to be handled differently.
llvm-svn: 125559
-Checkers will be defined in the tablegen file 'Checkers.td'.
-Apart from checkers, we can define checker "packages" that will contain a collection of checkers.
-Checkers can be enabled with -analyzer-checker=<name> and disabled with -analyzer-disable-checker=<name> e.g:
Enable checkers from 'cocoa' and 'corefoundation' packages except the self-initialization checker:
-analyzer-checker=cocoa -analyzer-checker=corefoundation -analyzer-disable-checker=cocoa.SelfInit
-Introduces CheckerManager and CheckerProvider. CheckerProviders get the set of checker names to enable/disable and
register them with the CheckerManager which will be the entry point for all checker-related functionality.
Currently only the self-initialization checker takes advantage of the new mechanism.
llvm-svn: 125503
there were only three virtual methods of any significance.
The primary way to grab child iterators now is with
Stmt::child_range children();
Stmt::const_child_range children() const;
where a child_range is just a std::pair of iterators suitable for
being llvm::tie'd to some locals. I've left the old child_begin()
and child_end() accessors in place, but it's probably a substantial
penalty to grab the iterators individually now, since the
switch-based dispatch is kindof inherently slower than vtable
dispatch. Grabbing them together is probably a slight win over the
status quo, although of course we could've achieved that with vtables, too.
I also reclassified SwitchCase (correctly) as an abstract Stmt
class, which (as the first such class that wasn't an Expr subclass)
required some fiddling in a few places.
There are somewhat gross metaprogramming hooks in place to ensure
that new statements/expressions continue to implement
getSourceRange() and children(). I had to work around a recent clang
bug; dgregor actually fixed it already, but I didn't want to
introduce a selfhosting dependency on ToT.
llvm-svn: 125183
The optimization involves eagerly pruning ExplodedNodes from the ExplodedGraph that contain
practically no difference between the predecessor and successor nodes. For example, if
the state is different between a predecessor and a node, the node is left in. Only for
the 'environment' component of the state do we not care if the ExplodedNodes are different.
This paves the way for future optimizations where we can reclaim the environment objects.
llvm-svn: 125154
Eventually there will also be a lib/StaticAnalyzer/Frontend that will handle initialization and checker registration.
Yet another library to avoid cyclic dependencies between Core and Checkers.
llvm-svn: 125124
A common pattern in classes with multiple initializers is to put the
subclass's common initialization bits into a static function that receives
the value of 'self', e.g:
if (!(self = [super init]))
return nil;
if (!(self = _commonInit(self)))
return nil;
It was reported that 'self' was not set to the result of [super init].
Until we can use inter-procedural analysis, in such a call, transfer the
ObjCSelfInitChecker flags associated with 'self' to the result of the call.
Fixes rdar://8937441 & http://llvm.org/PR9094
llvm-svn: 124940
We translate property accesses to obj-c messages by simulating "loads" or "stores" to properties
using a pseudo-location SVal kind (ObjCPropRef).
Checkers can now reason about obj-c messages for both explicit message expressions and implicit
messages due to property accesses.
llvm-svn: 124161
messages that are sent for handling properties in dot syntax.
Replace all direct uses of ObjCMessageExpr in the checkers and checker interface with ObjCMessage.
llvm-svn: 124159
that captures the substitution of a non-type template argument pack
for a non-type template parameter pack within a pack expansion that
cannot be fully expanded. This follows the approach taken by
SubstTemplateTypeParmPackType.
llvm-svn: 123506
dead stores within nested assignments. I have
never seen an actual bug found by this specific
warning, and it can lead to many false positives.
llvm-svn: 123394
template argument (described by an expression, of course). For
example:
template<int...> struct int_tuple { };
template<int ...Values>
struct square {
typedef int_tuple<(Values*Values)...> type;
};
It also lays the foundation for pack expansions in an initializer-list.
llvm-svn: 122751
SimpleSValBuilder. This clears up some
false positives emitted by ArrayBoundCheckerV2
due to the lack of support for pointer arithmetic.
llvm-svn: 122546
layout. :)
Rename the 'EntoSA' directories to 'StaticAnalyzer'.
Internally we will still use the 'ento' namespace
for the analyzer engine (unless there are further
sabre rattlings...).
llvm-svn: 122514
Anna Zaks