We have several reports of false positives coming from libc++. For example,
there are reports of false positives in std::regex, std::wcout, and also
a bunch of issues are reported in https://reviews.llvm.org/D30593. In many
cases, the analyzer trips over the complex libc++ code invariants. Let's turn
off the reports coming from these headers until we can re-evalate the support.
We can turn this back on once we individually suppress all known false
positives and perform deeper evaluation on large codebases that use libc++.
We'd also need to commit to doing these evaluations regularly as libc++
headers change.
Differential Revision: https://reviews.llvm.org/D30798
llvm-svn: 297429
Some of the magic functions take arguments of arbitrary type. However,
for semantic correctness, the compiler still requires a declaration
of these functions with the correct type. Since C does not have
argument-type-overloaded function, this made those functions hard to
use in C code. Improve this situation by allowing arbitrary suffixes
in the affected magic functions' names, thus allowing the user to
create different declarations for different types.
A patch by Keno Fischer!
Differential Revision: https://reviews.llvm.org/D30589
llvm-svn: 297325
Add a bug visitor to the taint checker to make it easy to distinguish where
the tainted value originated. This is especially useful when the original
taint source is obscured by complex data flow.
A patch by Vlad Tsyrklevich!
Differential Revision: https://reviews.llvm.org/D30289
llvm-svn: 297324
This patch makes the valist check more robust to the different AST variants on
different platforms and also fixes a FIXME.
Differential Revision: https://reviews.llvm.org/D30157
llvm-svn: 297153
Summary:
The changes contained in this patch are:
1. Defines a new AST node `CoawaitDependentExpr` for representing co_await expressions while the promise type is still dependent.
2. Correctly detect and transform the 'co_await' operand to `p.await_transform(<expr>)` when possible.
3. Change the initial/final suspend points to build during the initial parse, so they have the correct operator co_await lookup results.
4. Fix transformation of the CoroutineBodyStmt so that it doesn't re-build the final/initial suspends.
@rsmith: This change is a little big, but it's not trivial for me to split it up. Please let me know if you would prefer this submitted as multiple patches.
Reviewers: rsmith, GorNishanov
Reviewed By: rsmith
Subscribers: ABataev, rsmith, mehdi_amini, cfe-commits
Differential Revision: https://reviews.llvm.org/D26057
llvm-svn: 297093
* ExprEngine assumes that OpenMP statements should never appear in CFG.
However, current CFG doesn't know anything about OpenMP and passes
such statements as CFG nodes causing "UNREACHABLE executed!" crashes.
Since there is no OpenMP implementation in ExprEngine or CFG,
we stop the analysis on OpenMP statements to avoid crashes.
This fixes PR31835.
Differential Revision: https://reviews.llvm.org/D30565
llvm-svn: 296884
In the following code involving GNU statement-expression extension:
struct S {
~S();
};
void foo() {
const S &x = ({ return; S(); });
}
function 'foo()' returns before reference x is initialized. We shouldn't call
the destructor for the temporary object lifetime-extended by 'x' in this case,
because the object never gets constructed in the first place.
The real problem is probably in the CFG somewhere, so this is a quick-and-dirty
hotfix rather than the perfect solution.
A patch by Artem Dergachev!
rdar://problem/30759076
Differential Revision: https://reviews.llvm.org/D30499
llvm-svn: 296646
Fix a crash in the ObjCPropertyChecker when analyzing a 'copy' property of an
NSMutable* type in a protocol.
rdar://problem/30766684
Differential Revision: https://reviews.llvm.org/D30482
llvm-svn: 296562
Summary: SimpleConstraintManager is difficult to use, and makes assumptions about capabilities of the constraint manager. This patch refactors out those portions into a new RangedConstraintManager, and also fixes some issues with camel case, formatting, and confusing naming.
Reviewers: zaks.anna, dcoughlin
Subscribers: mgorny, xazax.hun, NoQ, rgov, cfe-commits
Differential Revision: https://reviews.llvm.org/D26061
llvm-svn: 296242
During the review of D29567 it turned out the caching in CallDescription is not implemented properly. In case an identifier does not exist in a translation unit, repeated identifier lookups will be done which might have bad impact on the performance. This patch guarantees that the lookup is only executed once. Moreover this patch fixes a corner case when the identifier of CallDescription does not exist in the translation unit and the called function does not have an identifier (e.g.: overloaded operator in C++).
Differential Revision: https://reviews.llvm.org/D29884
llvm-svn: 295186
Summary:
In VirtualCallChecker, handle indirect calls.
getDirectCallee() can be nullptr, and dyn_cast(nullptr) is UB
Reviewers: bkramer
Subscribers: cfe-commits
Differential Revision: https://reviews.llvm.org/D29303
llvm-svn: 293604
This is an attempt to avoid new false positives caused by the reverted r292800,
however the scope of the fix is significantly reduced - some variables are still
in incorrect memory spaces.
Relevant test cases added.
rdar://problem/30105546
rdar://problem/30156693
Differential revision: https://reviews.llvm.org/D28946
llvm-svn: 293043
This reverts commit r292800.
It is causing null pointer dereference false positives when a block that
captures a static local is evaluated at the top level.
llvm-svn: 292874
When a block within a function accesses a function's static local variable,
this local is captured by reference rather than copied to the heap.
Therefore this variable's memory space is known: StaticGlobalSpaceRegion.
Used to be UnknownSpaceRegion, same as for stack locals.
Fixes a false positive in MacOSXAPIChecker.
rdar://problem/30105546
Differential revision: https://reviews.llvm.org/D28946
llvm-svn: 292800
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
The checker has several false positives that this patch addresses:
- Do not check if the return status has been compared to error (or no error) at the time when leaks are reported since the status symbol might no longer be alive. Instead, pattern match on the assume and stop tracking allocated symbols on error paths.
- The checker used to report error when an unknown symbol was freed. This could lead to false positives, let's not repot those. This leads to loss of coverage in double frees.
- Do not enforce that we should only call free if we are sure that error was not returned and the pointer is not null. That warning is too noisy and we received several false positive reports about it. (I removed: "Only call free if a valid (non-NULL) buffer was returned")
- Use !isDead instead of isLive in leak reporting. Otherwise, we report leaks for objects we loose track of. This change triggered change #1.
This also adds checker specific dump to the state.
Differential Revision: https://reviews.llvm.org/D28330
llvm-svn: 291866
This replaces the hack in r291754, which was fixing pr31592, which was
caused by r291754, with a more appropriate solution.
rdar://problem/28832541
Differential revision: https://reviews.llvm.org/D28602
llvm-svn: 291781
A hotfix for pr31592 that fixes the crash but not the root cause of the problem.
We need to update the analyzer engine further to account for AST changes
introduced in r289618. At the moment we're erroneously performing a redundant
lvalue-to-rvalue cast in this scenario, and squashing the rvalue of the object
bound to the reference into the reference itself.
rdar://problem/28832541
llvm-svn: 291754
Sema treats pointers to static member functions as having function pointer
type, so treat treat them as function pointer values in the analyzer as well.
This prevents an assertion failure in SValBuilder::evalBinOp caused by code
that expects function pointers to be Locs (in contrast, PointerToMember values
are nonlocs).
Differential Revision: https://reviews.llvm.org/D28033
llvm-svn: 291581
This patch is to implement sema and parsing for 'target teams distribute simd’ pragma.
Differential Revision: https://reviews.llvm.org/D28252
llvm-svn: 291579
Aleksey Shlypanikov pointed out my mistake in migrating an explicit
unique_ptr to auto - I was expecting the function returned a unique_ptr,
but instead it returned a raw pointer - introducing a leak.
Thanks Aleksey!
This reapplies r291184, reverted in r291249.
llvm-svn: 291270
The one use of CheckerManager (AnalysisConsumer, calling
createCheckerManager) keeps a strong reference to the AnalysisOptions
anyway, so this ownership wasn't necessary.
(I'm not even sure AnalysisOptions needs ref counting at all - but
that's more involved)
llvm-svn: 291017
This patch is to implement sema and parsing for 'target teams distribute parallel for simd’ pragma.
Differential Revision: https://reviews.llvm.org/D28202
llvm-svn: 290862
This patch is to implement sema and parsing for 'target teams distribute parallel for’ pragma.
Differential Revision: https://reviews.llvm.org/D28160
llvm-svn: 290725
This patch is to implement sema and parsing for 'target teams distribute' pragma.
Differential Revision: https://reviews.llvm.org/D28015
llvm-svn: 290508
The patch also simplifies an assume of a constraint of the form: "(exp comparison_op expr) != 0" to true into an assume of "exp comparison_op expr" to true. (And similarly, an assume of the form "(exp comparison_op expr) == 0" to true as an assume of exp comparison_op expr to false.) which improves precision overall.
https://reviews.llvm.org/D22862
llvm-svn: 290505
The patch also simplifies an assume of a constraint of the form: "(exp comparison_op expr) != 0" to true into an assume of "exp comparison_op expr" to true. (And similarly, an assume of the form "(exp comparison_op expr) == 0" to true as an assume of exp comparison_op expr to false.) which improves precision overall.
https://reviews.llvm.org/D22862
llvm-svn: 290413
Update the GTestChecker to tighten up the API detection and make it
cleaner in response to post-commit feedback. Also add tests for when
temporary destructors are enabled to make sure we get the expected behavior
when inlining constructors for temporaries.
llvm-svn: 290352
Warnings with suppress-on-sink are discarded during FlushReports when
BugReporter notices that all paths in ExplodedGraph that pass through the
warning eventually run into a sink node.
However, suppress-on-sink fails to filter out false positives when the analysis
terminates too early - by running into analyzer limits, such as block count
limits or graph size limits - and the interruption hits the narrow window
between throwing the leak report and reaching the no-return function call. In
such case the report is there, however suppression-on-sink doesn't work, because
the sink node was never constructed in the incomplete ExplodedGraph.
This patch implements a very partial solution: also suppress reports thrown
against a statement-node that corresponds to a statement that belongs to a
no-return block of the CFG.
rdar://problem/28832541
Differential Revision: https://reviews.llvm.org/D28023
llvm-svn: 290341
gtest is a widely-used unit-testing API. It provides macros for unit test
assertions:
ASSERT_TRUE(p != nullptr);
that expand into an if statement that constructs an object representing
the result of the assertion and returns when the assertion is false:
if (AssertionResult gtest_ar_ = AssertionResult(p == nullptr))
;
else
return ...;
Unfortunately, the analyzer does not model the effect of the constructor
precisely because (1) the copy constructor implementation is missing from the
the header (so it can't be inlined) and (2) the boolean-argument constructor
is constructed into a temporary (so the analyzer decides not to inline it since
it doesn't reliably call temporary destructors right now).
This results in false positives because the analyzer does not realize that the
the assertion must hold along the non-return path.
This commit addresses the false positives by explicitly modeling the effects
of the two un-inlined constructors on the AssertionResult state.
I've added a new package, "apiModeling", for these kinds of checkers that
model APIs but don't emit any diagnostics. I envision all the checkers in
this package always being on by default.
This addresses the false positives reported in PR30936.
Differential Revision: https://reviews.llvm.org/D27773
rdar://problem/22705813
llvm-svn: 290143
The analyzer's CFG currently doesn't have nodes for calls to temporary
destructors. This causes the analyzer to explore infeasible paths in which
a no-return destructor would have stopped exploration and so results in false
positives when no-return destructors are used to implement assertions.
To mitigate these false positives, this patch stops generates a sink after
evaluating a constructor on a temporary object that has a no-return destructor.
This results in a loss of coverage because the time at which the destructor is
called may be after the time of construction (especially for lifetime-extended
temporaries).
This addresses PR15599.
rdar://problem/29131566
llvm-svn: 290140
Gabor Horvath