express library-level dependencies within Clang.
This is no more verbose really, and plays nicer with the rest of the
CMake facilities. It should also have no change in functionality.
llvm-svn: 158888
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
Chandler Carruth