Commit Graph

2743 Commits

Author SHA1 Message Date
Leslie Zhai e3986c544d [analyzer] Teach the MallocChecker about Glib API for two arguments
Reviewers: zaks.anna, NoQ, danielmarjamaki

Reviewed By: zaks.anna, NoQ, danielmarjamaki

Subscribers: cfe-commits, kalev, pwithnall

Differential Revision: https://reviews.llvm.org/D30771

llvm-svn: 301384
2017-04-26 05:33:14 +00:00
Artem Dergachev cbd7cd8360 [analyzer] Improve subscripting null arrays for catching null dereferences.
Array-to-pointer cast now works correctly when the pointer to the array
is concrete, eg. null, which allows further symbolic calculations involving
such values.

Inlined defensive checks are now detected correctly when the resulting null
symbol is being array-subscripted before dereference.

Differential Revision: https://reviews.llvm.org/D32291

llvm-svn: 301251
2017-04-24 20:55:07 +00:00
Artem Dergachev 37de888867 [analyzer] Improve suppression for inlined defensive checks before operator &.
Null dereferences are suppressed if the lvalue was constrained to 0 for the
first time inside a sub-function that was inlined during analysis, because
such constraint is a valid defensive check that does not, by itself,
indicate that null pointer case is anyhow special for the caller.

If further operations on the lvalue are performed, the symbolic lvalue is
collapsed to concrete null pointer, and we need to track where does the null
pointer come from.

Improve such tracking for lvalue operations involving operator &.

rdar://problem/27876009

Differential Revision: https://reviews.llvm.org/D31982

llvm-svn: 301224
2017-04-24 19:30:33 +00:00
Alexander Shaposhnikov 015da3534a [analyzer] Fix assert in ExprEngine::processSwitch
This diff replaces getTypeSize(CondE->getType())) 
with getIntWidth(CondE->getType())) in ExprEngine::processSwitch.
These calls are not equivalent for bool, see ASTContext.cpp
Add a test case.

Test plan:
make check-clang-analysis
make check-clang

Differential revision: https://reviews.llvm.org/D32328

llvm-svn: 300936
2017-04-21 01:05:26 +00:00
Artem Dergachev 12294f8d2e [analyzer] Simplify values in binary operations a bit more aggressively.
SValBuilder tries to constant-fold symbols in the left-hand side of the symbolic
expression whenever it fails to evaluate the expression directly. However, it
only constant-folds them when they are atomic expressions, not when they are
complicated expressions themselves. This patch adds recursive constant-folding
to the left-hand side subexpression (there's a lack of symmetry because we're
trying to have symbols on the left and constants on the right). As an example,
we'd now be able to handle operations similar to "$x + 1 < $y", when $x is
constrained to a constant.

rdar://problem/31354676

Differential Revision: https://reviews.llvm.org/D31886

llvm-svn: 300178
2017-04-13 07:20:04 +00:00
Alexander Shaposhnikov 5f24c12dc4 [analyzer] Add a check for IvarRegion in getExtraInvalidatedValues
This diff adds a defensive check in getExtraInvalidatedValues
for the case when there are no regions for the ivar associated with
a property. Corresponding test case added.

Test plan:
make check-clang
make check-clang-analysis

llvm-svn: 300114
2017-04-12 22:00:13 +00:00
Reid Kleckner 2ae37c15c3 [lit] Fix Analysis test format pickling error
Move the test format into a standalone .py file and add it to the site
module search path. This allows us to run the test on Windows, and it
makes it compatible with the multiprocessing.Pool lit test execution
strategy.

I think this test was only passing everywhere else because
multiprocessing uses 'fork' to spawn workers, so the test format never
needs to be pickled.

llvm-svn: 299577
2017-04-05 18:56:48 +00:00
Daniel Marjamaki 2641a52ee4 [analyzer] alpha.core.Conversion - Fix false positive for 'U32 += S16;' expression, that is not unsafe
Summary:
The alpha.core.Conversion was too strict about compound assignments and could warn even though there is no problem.

Differential Revision: https://reviews.llvm.org/D25596

llvm-svn: 299523
2017-04-05 08:57:04 +00:00
Dominic Chen 08f943c563 [analyzer] Add new Z3 constraint manager backend
Summary: Implement new Z3 constraint manager backend.

Reviewers: zaks.anna, dcoughlin, NoQ, xazax.hun

Subscribers: mgorny, cfe-commits

Differential Revision: https://reviews.llvm.org/D28952

llvm-svn: 299463
2017-04-04 19:52:25 +00:00
Aaron Ballman 4d3355a21c Correcting a typo; NFC.
llvm-svn: 299094
2017-03-30 18:11:20 +00:00
Artem Dergachev 7333a9ea11 [analyzer] Fix symbolication for unknown unary increment/decrement results.
If the value is known, but we cannot increment it, conjure a symbol to
represent the result of the operation based on the operator expression,
not on the sub-expression.

In particular, no longer crash on comparing a result of a LocAsInteger increment
to a constant integer.

rdar://problem/31067356

Differential Revision: https://reviews.llvm.org/D31289

llvm-svn: 298927
2017-03-28 15:57:12 +00:00
Artem Dergachev 647804a84a [analyzer] When creating a temporary object, properly copy the value into it.
Adjustments should be considered properly; we should copy the unadjusted object
over the whole temporary base region. If the unadjusted object is no longer
available in the Environment, invalidate the temporary base region, and then
copy the adjusted object into the adjusted sub-region of the temporary region.

This fixes a regression introduced by r288263, that caused various
false positives, due to copying only adjusted object into the adjusted region;
the rest of the base region therefore remained undefined.
Before r288263, the adjusted value was copied over the unadjusted region,
which is incorrect, but accidentally worked better due to how region store
disregards compound value bindings to non-base regions.

An additional test machinery is introduced to make sure that despite making
two binds, we only notify checkers once for both of them, without exposing
the partially copied objects.

This fix is a hack over a hack. The proper fix would be to model C++ temporaries
in the CFG, and after that dealing with adjustments would no longer be
necessary, and the values we need would no longer disappear from the
Environment.

rdar://problem/30658168

Differential Revision: https://reviews.llvm.org/D30534

llvm-svn: 298924
2017-03-28 15:43:26 +00:00
Artem Dergachev 356151ff5f [analyzer] Add MisusedMovedObjectChecker for detecting use-after-move errors.
The checker currently warns on copying, moving, or calling methods on an object
that was recently std::move'd from. It understands a set of "state reset"
methods that bring a moved-from object back to a well-specified state.

Patch by Peter Szecsi!

Differential Revision: https://reviews.llvm.org/D24246

llvm-svn: 298698
2017-03-24 09:52:30 +00:00
Gabor Horvath 60eec1ac1b [analyzer] Fix a rare crash for valist check.
It looks like on some host-triples the result of a valist related expr can be
a LazyCompoundVal. Handle that case in the check.

Patch by Abramo Bagnara!

llvm-svn: 297619
2017-03-13 12:48:26 +00:00
Gabor Horvath 829c6bc04a [analyzer] Extend block in critical section check with C11 and Pthread APIs.
Patch by Zoltan Daniel Torok!

Differential Revision: https://reviews.llvm.org/D29567

llvm-svn: 297461
2017-03-10 14:50:12 +00:00
Anna Zaks ae4772140f [analyzer] Turn suppress-c++-stdlib on by default
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
2017-03-10 00:33:19 +00:00
Anna Zaks 12d0c8d662 [analyzer] Extend taint propagation and checking to support LazyCompoundVal
A patch by Vlad Tsyrklevich!

Differential Revision: https://reviews.llvm.org/D28445

llvm-svn: 297326
2017-03-09 00:01:16 +00:00
Anna Zaks 37faed97c1 [analyzer] Improve usability of ExprInspectionChecker
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
2017-03-09 00:01:10 +00:00
Anna Zaks d4e43ae22a [analyzer] Add bug visitor for taint checker.
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
2017-03-09 00:01:07 +00:00
Anna Zaks bbec97ca2c [analyzer] Teach the MallocChecker about about Glib API
A patch by Leslie Zhai!

Differential Revision: https://reviews.llvm.org/D28348

llvm-svn: 297323
2017-03-09 00:01:01 +00:00
Daniel Marjamaki 3d8d6ed01f [analyzer] Clarify 'uninitialized function argument' messages
Differential Revision: https://reviews.llvm.org/D30341

llvm-svn: 297283
2017-03-08 15:22:24 +00:00
Daniel Marjamaki cf715bd330 [analyzer] Fix crashes in CastToStruct checker for undefined structs
This crash was reported in https://bugs.llvm.org//show_bug.cgi?id=31173

Differential Revision: https://reviews.llvm.org/D28297

llvm-svn: 297187
2017-03-07 19:20:48 +00:00
Gabor Horvath dbf2790a1f [analyzer] Improve valist checks and move it out from alpha state.
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
2017-03-07 16:04:23 +00:00
Dominic Chen 184c6242fa Reland 4: [analyzer] NFC: Update test infrastructure to support multiple constraint managers
Summary: Replace calls to %clang/%clang_cc1 with %clang_analyze_cc1 when invoking static analyzer, and perform runtime substitution to select the appropriate constraint manager, per D28952.

Reviewers: xazax.hun, NoQ, zaks.anna, dcoughlin

Subscribers: mgorny, rgov, mikhail.ramalho, a.sidorin, cfe-commits

Differential Revision: https://reviews.llvm.org/D30373

llvm-svn: 296895
2017-03-03 18:02:02 +00:00
Aleksei Sidorin f82a63277a [Analyzer] Terminate analysis on OpenMP code instead of assertion crash
* 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
2017-03-03 16:58:53 +00:00
Dominic Chen 09d66f7528 Revert "Reland 3: [analyzer] NFC: Update test infrastructure to support multiple constraint managers"
This reverts commit ea36f1406e1f36bf456c3f3929839b024128e468.

llvm-svn: 296841
2017-03-02 23:30:53 +00:00
Dominic Chen feaf9ff5ee Reland 3: [analyzer] NFC: Update test infrastructure to support multiple constraint managers
Summary: Replace calls to %clang/%clang_cc1 with %clang_analyze_cc1 when invoking static analyzer, and perform runtime substitution to select the appropriate constraint manager, per D28952.

Reviewers: xazax.hun, NoQ, zaks.anna, dcoughlin

Subscribers: mgorny, rgov, mikhail.ramalho, a.sidorin, cfe-commits

Differential Revision: https://reviews.llvm.org/D30373

llvm-svn: 296837
2017-03-02 23:05:45 +00:00
Dominic Chen 4a90bf8c3f Revert "Reland 2: [analyzer] NFC: Update test infrastructure to support multiple constraint managers"
This reverts commit f93343c099fff646a2314cc7f4925833708298b1.

llvm-svn: 296836
2017-03-02 22:58:06 +00:00
Dominic Chen 1cb0256a3c Reland 2: [analyzer] NFC: Update test infrastructure to support multiple constraint managers
Summary: Replace calls to %clang/%clang_cc1 with %clang_analyze_cc1 when invoking static analyzer, and perform runtime substitution to select the appropriate constraint manager, per D28952.

Reviewers: xazax.hun, NoQ, zaks.anna, dcoughlin

Subscribers: mgorny, rgov, mikhail.ramalho, a.sidorin, cfe-commits

Differential Revision: https://reviews.llvm.org/D30373

llvm-svn: 296835
2017-03-02 22:45:24 +00:00
Devin Coughlin bfa8e28dbb [analyzer] pr32088: Don't destroy the temporary if its initializer causes return.
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
2017-03-01 17:48:39 +00:00
Devin Coughlin 1bf65c8c0d [Analyzer] Fix crash in ObjCPropertyChecker on protocol property
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
2017-03-01 01:47:37 +00:00
Dominic Chen 00355a51d0 Revert "Reland: [analyzer] NFC: Update test infrastructure to support multiple constraint managers"
This reverts commit 1b28d0b10e1c8feccb971abb6ef7a18bee589830.

llvm-svn: 296422
2017-02-28 01:50:23 +00:00
Dominic Chen 59cd893320 Reland: [analyzer] NFC: Update test infrastructure to support multiple constraint managers
Summary: Replace calls to %clang/%clang_cc1 with %clang_analyze_cc1 when invoking static analyzer, and perform runtime substitution to select the appropriate constraint manager, per D28952.

Reviewers: xazax.hun, NoQ, zaks.anna, dcoughlin

Subscribers: mgorny, rgov, mikhail.ramalho, a.sidorin, cfe-commits

Differential Revision: https://reviews.llvm.org/D30373

llvm-svn: 296414
2017-02-28 00:02:36 +00:00
Daniel Marjamaki e97838f49e [analyzer] clarify 'result is garbage value' when it is out of bounds
Differential Revision: https://reviews.llvm.org/D28278

llvm-svn: 296326
2017-02-27 10:44:24 +00:00
Dominic Chen 8589e10c30 Revert "[analyzer] NFC: Update test infrastructure to support multiple constraint managers"
This reverts commit 8e7780b9e59ddaad1800baf533058d2c064d4787.

llvm-svn: 296317
2017-02-27 03:29:25 +00:00
Dominic Chen 02064a3076 [analyzer] NFC: Update test infrastructure to support multiple constraint managers
Summary: Replace calls to %clang/%clang_cc1 with %clang_analyze_cc1 when invoking static analyzer, and perform runtime substitution to select the appropriate constraint manager, per D28952.

Reviewers: xazax.hun, NoQ, zaks.anna, dcoughlin

Subscribers: mgorny, rgov, mikhail.ramalho, a.sidorin, cfe-commits

Differential Revision: https://reviews.llvm.org/D30373

llvm-svn: 296312
2017-02-27 02:36:15 +00:00
Aleksei Sidorin ee0351631b [analyzer] Do not duplicate call graph nodes for functions that have definition and forward declaration
Patch by Ivan Sidorenko!

Differential Revision: https://reviews.llvm.org/D29643

llvm-svn: 295644
2017-02-20 09:16:48 +00:00
Daniel Marjamaki dc53b680cb [analyzer] Revert 295545. There are buildbot failures.
llvm-svn: 295548
2017-02-18 16:31:35 +00:00
Daniel Marjamaki 1149166bb9 [analyzer] Fix crash in CastToStruct when there is no record definition
This crash was reported in https://bugs.llvm.org//show_bug.cgi?id=31173

Differential Revision: https://reviews.llvm.org/D28297

llvm-svn: 295545
2017-02-18 11:18:57 +00:00
Gabor Horvath 3b008536f3 [analyzer] Fix an assertion fail in CStringSyntaxChecker.
Differential Revision: https://reviews.llvm.org/D29384

llvm-svn: 293874
2017-02-02 08:20:54 +00:00
Sam McCall 93590e09d5 In VirtualCallChecker, handle indirect calls
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
2017-01-31 05:23:20 +00:00
Artem Dergachev 12caf8e1e6 [analyzer] Consider function call arguments while building CallGraph.
Function call can appear in the arguments of another function call, eg.:

  foo(bar());

This patch adds support for such cases.

Patch by Ivan Sidorenko!

Differential revision: https://reviews.llvm.org/D28905

llvm-svn: 293280
2017-01-27 12:14:56 +00:00
Michal Gorny 638ac70a92 [test] Port clang tests to canonicalized booleans
Use the new llvm_canonicalize_cmake_booleans() function to canonicalize
booleans for lit tests. Replace the duplicate ENABLE_CLANG* variables
used to hold canonicalized values with in-place canonicalization. Use
implicit logic in Python code to avoid overrelying on exact 0/1 values.

Differential Revision: https://reviews.llvm.org/D28529

llvm-svn: 293052
2017-01-25 13:11:45 +00:00
Artem Dergachev 55705955ce [analyzer] Fix MacOSXAPIChecker fp with static locals seen from nested blocks.
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
2017-01-25 10:21:45 +00:00
Devin Coughlin e1a5630213 Revert "[analyzer] Fix memory space of static locals seen from nested blocks."
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
2017-01-24 02:10:59 +00:00
Artem Dergachev 01728fbbc0 [analyzer] Fix memory space of static locals seen from nested blocks.
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
2017-01-23 16:57:11 +00:00
Anna Zaks dcfc191404 [analyzer] Support inlining of '[self classMethod]' and '[[self class] classMethod]'
Differential Revision: https://reviews.llvm.org/D28495

llvm-svn: 291867
2017-01-13 00:50:47 +00:00
Anna Zaks 14b1af5dcd [analyzer] Fix false positives in Keychain API checker
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
2017-01-13 00:50:41 +00:00
Artem Dergachev c9affb0dbd [analyzer] Avoid a crash in DereferenceChecker on string literal initializers.
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
2017-01-12 09:46:16 +00:00
Devin Coughlin aac894feba [analyzer] Fix crash in body farm for getter without implicit self.
Fix a crash in body farm when synthesizing a getter for a property
synthesized for a property declared in a protocol on a class extension
that shadows a declaration of the property in a category.

In this case, Sema doesn't fill in the implicit 'self' parameter for the getter
in the category, which leads to a crash when trying to synthesize the getter
for it.

To avoid the crash, skip getter synthesis in body farm if the self parameter is
not filled int.

rdar://problem/29938138

llvm-svn: 291635
2017-01-11 01:02:34 +00:00
Devin Coughlin dc9834f912 [analyzer] Treat pointers to static member functions as function pointers
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
2017-01-10 18:49:27 +00:00
Gabor Horvath 3d57457298 [analyzer] Add checker for iterators dereferenced beyond their range.
Patch by: Adam Balogh!

Differential Revision: https://reviews.llvm.org/D25660

llvm-svn: 291430
2017-01-09 09:52:32 +00:00
Anton Yartsev 5ac3720620 Fix for PR15623 (corrected r290413 reverted at 290415). The patch eliminates unwanted ProgramState checker data propagation from an operand of the logical operation to operation result.
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
2016-12-25 00:57:51 +00:00
Anton Yartsev b2a5eb87f8 Revert changes made by r290413 until regression is fixed.
llvm-svn: 290415
2016-12-23 04:09:18 +00:00
Anton Yartsev 1a2a9e3087 Fix for PR15623. The patch eliminates unwanted ProgramState checker data propagation from an operand of the logical operation to operation result.
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
2016-12-23 03:31:00 +00:00
Devin Coughlin e17f621529 [analyzer] Update GTestChecker to tighten API detection
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
2016-12-22 17:52:57 +00:00
Artem Dergachev 0e0a8b4d85 [analyzer] Improve suppress-on-sink behavior in incomplete analyses.
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
2016-12-22 14:48:52 +00:00
Devin Coughlin 8beac28564 [analyzer] Add checker modeling gtest APIs.
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
2016-12-19 22:50:31 +00:00
Devin Coughlin 5b1ee2fad9 [analyzer] Add sink after construction of temporary with no-return destructor.
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
2016-12-19 22:23:22 +00:00
Devin Coughlin aa0fd76be3 [analyzer] UnixAPIChecker: Don't diagnose for functions in C++ namespaces
Update the UnixAPIChecker to not diagnose for calls to functions that
are declared in C++ namespaces. This avoids false positives when a
namespaced function has the same name as a Unix API.

This address PR28331.

llvm-svn: 290023
2016-12-17 01:08:17 +00:00
Devin Coughlin 74810145b0 [analyzer] Extend UnixAPIChecker open() checks to handle openat().
The openat() API has similar constraints to the open() API -- it just takes
an extra parameter.

rdar://problem/29526458

llvm-svn: 290005
2016-12-16 23:31:56 +00:00
Devin Coughlin e3b75ded98 [analyzer] Fix crash in MallocChecker.
Fix a crash in the MallocChecker when the extent size for the argument
to new[] is not known.

A patch by Abramo Bagnara and Dániel Krupp!

https://reviews.llvm.org/D27849

Differential Revision: https://reviews.llvm.org/D27849

llvm-svn: 289970
2016-12-16 18:41:40 +00:00
Artem Dergachev 85c9211043 [analyzer] Add another exception for Qt in MallocChecker
Treat pointers passed to QObject::connectImpl() as escaping.

rdar://problem/29550440

Differential Revision: https://reviews.llvm.org/D27717

llvm-svn: 289939
2016-12-16 12:21:55 +00:00
Anna Zaks 44cdeb1da2 [analyzer] Teach the analyzer that pointers can escape into __cxa_demangle
This fixes a reported false positive in the malloc checker.

Differential Revision: https://reviews.llvm.org/D27599

llvm-svn: 289886
2016-12-15 22:55:18 +00:00
Anna Zaks 6d4e76b988 [analyzer] Refine the diagnostics in the nullability checker to differentiate between nil and null
This is a big deal for ObjC, where nullability annotations are extensively
used. I've also changed "Null" -> "null" and removed "is" as this is the
pattern that Sema is using.

Differential Revision: https://reviews.llvm.org/D27600

llvm-svn: 289885
2016-12-15 22:55:15 +00:00
Anna Zaks 40c74c6d22 [analyzer] Refer to macro names in diagnostics for macros representing a literal
When a macro expending to a literal is used in a comparison, use the macro name
in the diagnostic rather than the literal. This improves readability of path
notes.

Added tests for various macro literals that could occur. Only BOOl, Int, and
NULL tests have changed behavior with this patch.

Differential Revision: https://reviews.llvm.org/D27726

llvm-svn: 289884
2016-12-15 22:55:11 +00:00
Anna Zaks 232ecfdf9c [analyzer] Include type name in Retain Count Checker diagnostics
The more detailed diagnostic will make identifying which object the
diagnostics refer to easier.

Differential Revision: https://reviews.llvm.org/D27740

llvm-svn: 289883
2016-12-15 22:55:03 +00:00
Devin Coughlin 64c01f7bef [analyzer] Add a new SVal to support pointer-to-member operations.
Add a new type of NonLoc SVal for C++ pointer-to-member operations. This SVal
supports both pointers to member functions and pointers to member data.

A patch by Kirill Romanenkov!

Differential Revision: https://reviews.llvm.org/D25475

llvm-svn: 289873
2016-12-15 21:27:06 +00:00
Artem Dergachev e69d2e47e5 [analyzer] Detect ObjC properties that are both (copy) and Mutable.
When an Objective-C property has a (copy) attribute, the default setter
for this property performs a -copy on the object assigned.

Calling -copy on a mutable NS object such as NSMutableString etc.
produces an immutable object, NSString in our example.
Hence the getter becomes type-incorrect.

rdar://problem/21022397

Differential Revision: https://reviews.llvm.org/D27535

llvm-svn: 289554
2016-12-13 17:19:18 +00:00
Devin Coughlin 3e5f0474ca [analyzer] Improve VirtualCallChecker diagnostics and move into optin package.
The VirtualCallChecker is in alpha because its interprocedural diagnostics
represent the call path textually in the diagnostic message rather than with a
path sensitive diagnostic.

This patch turns off the AST-based interprocedural analysis in the checker so
that no call path is needed and improves with diagnostic text. With these
changes, the checker is ready to be moved into the optin package.

Ultimately the right fix is to rewrite this checker to be path sensitive -- but
there is still value in enabling the checker for intraprocedural analysis only
The interprocedural mode can be re-enabled with an -analyzer-config flag.

Differential Revision: https://reviews.llvm.org/D26768

llvm-svn: 289309
2016-12-10 01:16:09 +00:00
Artem Dergachev a4e2541a70 [analyzer] Add dispatch_data_create as a special case in RetainCountChecker.
This function receives a callback block. The analyzer suspects that this block
may be used to take care of releasing the libdispatch object returned from
the function. In fact, it doesn't - it only releases the raw data buffer.
Inform the analyzer about that. Fixes the resulting false negatives.

rdar://problem/22280098

Differential Revision: https://reviews.llvm.org/D27409

llvm-svn: 289047
2016-12-08 14:05:48 +00:00
Artem Dergachev d69e01297f [analyzer] pr31226: Disable CastSizeChecker in C++ because it's not quite ready.
Avoids a crash and a related false positive.

Investigation by Daniel Krupp!

llvm-svn: 288914
2016-12-07 16:12:26 +00:00
Dominic Chen 0dd2306538 [analyzer] Print type for SymbolRegionValues when dumping to stream
Reviewers: NoQ, dcoughlin, zaks.anna

Subscribers: cfe-commits

Differential Revision: https://reviews.llvm.org/D27365

llvm-svn: 288696
2016-12-05 20:30:11 +00:00
Devin Coughlin ab139a9e79 [analyzer] ObjCGenerics: Warn only on mismatch for invariant type parameters
On a method call, the ObjCGenerics checker uses the type tracked by
DynamicTypePropagation for the receiver to to infer substituted parmeter types
for the called methods and warns when the argument type does not match the
parameter.

Unfortunately, using the tracked type can result in false positives when the
receiver has a non-invariant type parameter and has been intentionally upcast.
For example, becaue NSArray's type parameter is covaraint, the following code
is perfectly safe:

NSArray<NSString *> *allStrings = ...
NSDate *date = ...;
NSArray<NSObject *> *allObjects = allStrings;
NSArray<NSObject *> *moreObjects = [allObjects arrayByAddingObject:date];

but the checker currently warns that the date parameter is not an NSString *.

To avoid this kind of false positive, the checker will now only warn when
the class defining the called method has only invariant type parameters.

rdar://problem/28803951

llvm-svn: 288677
2016-12-05 16:28:47 +00:00
Richard Smith b3189a1802 DR1213: element access on an array xvalue or prvalue produces an xvalue. In the
latter case, a temporary array object is materialized, and can be
lifetime-extended by binding a reference to the member access. Likewise, in an
array-to-pointer decay, an rvalue array is materialized before being converted
into a pointer.

This caused IR generation to stop treating file-scope array compound literals
as having static storage duration in some cases in C++; that has been rectified
by modeling such a compound literal as an lvalue. This also improves clang's
compatibility with GCC for those cases.

llvm-svn: 288654
2016-12-05 07:49:14 +00:00
Richard Smith 4baaa5ab52 DR616, and part of P0135R1: member access (or pointer-to-member access) on a
temporary produces an xvalue, not a prvalue. Support this by materializing the
temporary prior to performing the member access.

llvm-svn: 288563
2016-12-03 01:14:32 +00:00
Dominic Chen 1a154e082c [analyzer] Drop explicit mention of range constraint solver
Summary: The basic constraint solver was dropped in rL162384, leaving the range constraint solver as the default and only constraint solver. Explicitly specifying it is unnecessary, and makes it difficult to test with other solver backends.

Reviewers: zaks.anna, dcoughlin

Subscribers: cfe-commits

Differential Revision: https://reviews.llvm.org/D26694

llvm-svn: 288372
2016-12-01 17:06:39 +00:00
Artem Dergachev 28ee2d1b09 [analyzer] Construct temporary objects of correct types, destroy them properly.
When constructing a temporary object region, which represents the result of
MaterializeTemporaryExpr, track down the sub-expression for which the temporary
is necessary with a trick similar to the approach used in CodeGen, namely
by using Expr::skipRValueSubobjectAdjustments().

Then, create the temporary object region with type of that sub-expression.
That type would propagate further in a path-sensitive manner.

During destruction of lifetime-extened temporaries, consult the type of
the temporary object region, rather than the type of the lifetime-extending
variable, in order to call the correct destructor (fixes pr17001) and,
at least, not to crash by trying to call a destructor of a plain type
(fixes pr19539).

rdar://problem/29131302
rdar://problem/29131576

Differential Revision: https://reviews.llvm.org/D26839

llvm-svn: 288263
2016-11-30 19:02:44 +00:00
Artem Dergachev 7b75e3266c [analyzer] SValExplainer: Support ObjC ivars and __block variables.
Additionally, explain the difference between normal and heap-based
symbolic regions.

llvm-svn: 288260
2016-11-30 18:26:43 +00:00
Artem Dergachev 30ed5467a4 [analyzer] Minor fixes and improvements to debug.ExprInspection
- Fix the bug with transition handling in ExprInspectionChecker's
  checkDeadSymbols implementation.

- Test this bug by adding a new function clang_analyzer_numTimesReached() to
  catch number of passes through the code, which should be handy for testing
  against unintended state splits.

- Add two more functions should help debugging issues quickly without running
  the debugger or dumping exploded graphs - clang_analyzer_dump() which dump()s
  an SVal argument to a warning message, and clang_analyzer_printState(), which
  dump()s the current program state to stderr.

Differential Revision: https://reviews.llvm.org/D26835

llvm-svn: 288257
2016-11-30 17:57:18 +00:00
Artem Dergachev 22e28f4078 [analyzer] Fix a crash on accessing a field within a literal-initialized union.
Because in case of unions we currently default-bind compound values in the
store, this quick fix avoids the crash for this case.

Patch by Ilya Palachev and independently by Alexander Shaposhnikov!

Differential Revision: https://reviews.llvm.org/D26442

llvm-svn: 287618
2016-11-22 04:29:23 +00:00
Devin Coughlin 8693adfd46 [analyzer] Add check for when block is called with too few arguments.
The CallAndMessageChecker has an existing check for when a function pointer
is called with too few arguments. Extend this logic to handle the block
case, as well. While we're at it, do a drive-by grammar correction
("less" --> "fewer") on the diagnostic text.

llvm-svn: 287001
2016-11-15 18:40:46 +00:00
Devin Coughlin e4224cc9f7 [analyzer] Fix crash in NullabilityChecker calling block with too few arguments
Fix a crash when checking parameter nullability on a block invocation
with fewer arguments than the block declaration requires.

rdar://problem/29237566

llvm-svn: 286901
2016-11-14 22:46:02 +00:00
Devin Coughlin 8fa568d761 [analyzer] Update 'Automated' to 'Automatic' from r286694.
ARC is 'Automatic Reference Counting' and not 'Automated Reference Counting'.

llvm-svn: 286700
2016-11-12 01:50:04 +00:00
Devin Coughlin 3dc29a52c7 [analyzer] Fix copy-pasta in NullableReturnedFromNonnullChecker checker name.
The name of the NullableReturnedFromNonnullChecker in Checkers.td
was accidentally "NullablePassedToNonnull", which made it impossible
to explicitly turn the checker on.

rdar://problem/28354459

llvm-svn: 286697
2016-11-12 01:23:01 +00:00
Devin Coughlin d1fe08b8a9 [analyzer] Improve misleading RetainCountChcker diagnostic under ARC
Under automated reference counting the analyzer treats a methods -- even those
starting with  'copy' and friends -- as returning an unowned value. This is
because ownership of CoreFoundation objects must be transferred to ARC
with __bridge_transfer or CFBridgingRelease() before being returned as
ARC-managed bridged objects.

Unfortunately this could lead to a poor diagnostic inside copy methods under
ARC where the analyzer would complain about a leak of a returned CF value inside
a method "whose name does not start with 'copy'" -- even though the name did
start with 'copy'.

This commit improves the diagnostic under ARC to say inside a method "returned
from a method managed by Automated Reference Counting".

rdar://problem/28849667

llvm-svn: 286694
2016-11-12 01:03:06 +00:00
Devin Coughlin e477a0e5ec [analyzer] Teach RetainCountChecker about VTCompressionSessionEncodeFrame()
The context argument passed to VideoToolbox's
VTCompressionSessionEncodeFrame() function is ultimately passed to a callback
supplied when creating the compression session and so may be freed by that
callback.  To suppress false positives in this case, teach the retain count
checker to stop tracking that argument.

This isn't suppressed by the usual callback context mechanism because the call
to VTCompressionSessionEncodeFrame() doesn't include the callback itself.

rdar://problem/27685213

llvm-svn: 286633
2016-11-11 21:31:38 +00:00
Serge Pavlov a67a4d2f3c Make output of -ast-print a valid C++ code.
Output generated by option -ast-print looks like C/C++ code, and it
really is for plain C. For C++ the produced output was not valid C++
code, but the differences were small. With this change the output
is fixed and can be compiled. Tests are changed so that output produced
by -ast-print is compiled again with the same flags and both outputs are
compared.

Option -ast-print is extensively used in clang tests but it itself
was tested poorly, existing tests only checked that compiler did not
crash. There are unit tests in file DeclPrinterTest.cpp, but they test
only terse output mode.

Differential Revision: https://reviews.llvm.org/D26452

llvm-svn: 286439
2016-11-10 08:49:37 +00:00
Artem Dergachev 47fec16cd1 [analyzer] StdLibraryFunctions: provide platform-specific function summaries.
Because standard functions can be defined differently on different platforms,
this commit introduces a method for constructing summaries with multiple
variants, whichever matches better. It is also useful for supporting overloads.

Differential Revision: https://reviews.llvm.org/D25940

llvm-svn: 285852
2016-11-02 19:35:20 +00:00
Devin Coughlin 05c03845e7 [analyzer] Fix capitalization in ObjCSuperDealloc checker diagnostic.
Change "use of 'self'..." to "Use of 'self'...". The convention is to
start diagnostics with a capital letter.

rdar://problem/28322494

llvm-svn: 285759
2016-11-01 22:16:39 +00:00
Artem Dergachev 75f9d3ac7e [analyzer] Allow undefined values in performTrivialCopy.
Reading from a garbage pointer should be modeled as garbage,
and performTrivialCopy should be able to deal with any SVal input.

Patch by Ilya Palachev!

Differential Revision: https://reviews.llvm.org/D25727

llvm-svn: 285640
2016-10-31 21:11:20 +00:00
Artem Dergachev a21df23fd8 [analyzer] MacOSXAPIChecker: Improve warnings for __block vars in dispatch_once.
The checker already warns for __block-storage variables being used as a
dispatch_once() predicate, however it refers to them as local which is not quite
accurate, so we fix that.

Differential Revision: https://reviews.llvm.org/D26159

llvm-svn: 285637
2016-10-31 21:04:54 +00:00
Artem Dergachev aacc03c918 [analyzer] MacOSXAPIChecker: Disallow dispatch_once_t in ivars and heap.
Unlike global/static variables, calloc etc. functions that allocate ObjC
objects behave differently in terms of memory barriers, and hacks that make
dispatch_once as fast as it possibly could be start failing.

Differential Revision: https://reviews.llvm.org/D25909

llvm-svn: 285605
2016-10-31 17:27:26 +00:00
Artem Dergachev e14d881808 [analyzer] NumberObjectConversion: support more types, misc updates.
Support CFNumberRef and OSNumber objects, which may also be accidentally
converted to plain integers or booleans.

Enable explicit boolean casts by default in non-pedantic mode.

Improve handling for warnings inside macros.

Improve error messages.

Differential Revision: https://reviews.llvm.org/D25731

llvm-svn: 285533
2016-10-31 03:08:48 +00:00
Anna Zaks 5b2b39065c [analyzer] Report CFNumberGetValue API misuse
This patch contains 2 improvements to the CFNumber checker:
 - Checking of CFNumberGetValue misuse.
 - Treating all CFNumber API misuse errors as non-fatal. (Previously we treated errors that could cause uninitialized memory as syncs and the truncation errors as non-fatal.)

This implements a subset of functionality from https://reviews.llvm.org/D17954.

Differential Revision: https://reviews.llvm.org/D25876

llvm-svn: 285253
2016-10-26 22:51:47 +00:00
Artem Dergachev a7609fbb64 [analyzer] Fix an ARM buildbot after r284960.
I guess we should always specify triples in all analyzer tests, regardless.

llvm-svn: 284969
2016-10-24 12:54:27 +00:00
Artem Dergachev bba497fb65 [analyzer] Add StdLibraryFunctions checker.
This checker does not emit reports, however it influences the analysis
by providing complete summaries for, or otherwise improving modeling of,
various standard library functions.

This should reduce the number of infeasible paths explored during analysis.
The custom function summary format used in this checker is superior to
body farms by causing less unnecessary state splits,
which would result in better analysis performance.

Differential Revision: https://reviews.llvm.org/D20811

llvm-svn: 284960
2016-10-24 09:41:38 +00:00
Reid Kleckner 2e1538f282 Remove 24 instances of 'REQUIRES: shell'
Tests fall into one of the following categories:

- The requirement was unnecessary

- Additional quoting was required for backslashes in paths (see "sed -e
  's/\\/\\\\/g'") in the sanitizer tests.

- OpenMP used 'REQUIRES: shell' as a proxy for the test failing on
  Windows. Those tests fail there reliably, so use XFAIL instead.

I tried not to remove shell requirements that were added to suppress
flaky test failures, but if I screwed up, we can add it back as needed.

llvm-svn: 284793
2016-10-20 23:11:45 +00:00
Daniel Marjamaki fa1bf447d9 alpha.core.UnreachableCode - don't warn about unreachable code inside macro
In macros, 'do {...} while (0)' is often used. Don't warn about the condition 0 when it is unreachable.

Differential Revision: https://reviews.llvm.org/D25606

llvm-svn: 284477
2016-10-18 13:16:53 +00:00
Artem Dergachev 940c770d27 [analyzer] Add NumberObjectConversion checker.
When dealing with objects that represent numbers, such as Objective-C NSNumber,
the language provides little protection from accidentally interpreting
the value of a pointer to such object as the value of the number represented
by the object. Results of such mis-interpretation may be unexpected.

The checker attempts to fill this gap in cases when the code is obviously
incorrect.

With "Pedantic" option enabled, this checker enforces a coding style to
completely prevent errors of this kind (off by default).

Differential Revision: https://reviews.llvm.org/D22968

llvm-svn: 284473
2016-10-18 11:06:28 +00:00
Richard Smith 391fb8662a [c++1z] Include "noexcept" in builtin function types where appropriate. Fixes
an assertion failure looking up a matching ::operator delete for
__builtin_operator_delete.

llvm-svn: 284458
2016-10-18 07:13:55 +00:00
Devin Coughlin 684d19d879 Revert "Revert "[analyzer] Make MallocChecker more robust against custom redeclarations""
This reverts commit r284340 to reapply r284335. The bot breakage was due to
an unrelated change in the polybench test suite.

llvm-svn: 284351
2016-10-16 22:19:03 +00:00
Devin Coughlin eeb8d20db4 Revert "[analyzer] Make MallocChecker more robust against custom redeclarations"
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
2016-10-16 19:26:07 +00:00
Devin Coughlin 62ce463a35 [analyzer] Make MallocChecker more robust against custom redeclarations
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
2016-10-16 17:26:06 +00:00
Devin Coughlin 4fba10c394 Revert "[analyzer] Re-apply r283093 "Add extra notes to ObjCDeallocChecker""
Revert:
r283662: [analyzer] Re-apply r283093 "Add extra notes to ObjCDeallocChecker"
r283660: [analyzer] Fix build error after r283660 - remove constexpr strings.

It was causing an internal build bot to fail. It looks like in some cases
adding an extra note can cause scan-build plist output to drop a diagnostic
altogether.

llvm-svn: 284317
2016-10-16 00:30:08 +00:00
Devin Coughlin 0bd37a1a36 [analyzer] DeallocChecker: Don't warn about directly-set IBOutlet ivars on macOS
On macOS (but not iOS), if an ObjC property has no setter, the nib-loading code
for an IBOutlet is documented as directly setting the backing ivar without
retaining the value -- even if the property is 'retain'.

This resulted in false positives from the DeallocChecker for code that did not
release such ivars in -dealloc.

To avoid these false positives, treat IBOutlet ivars that back a property
without a setter as having an unknown release requirement in macOS.

rdar://problem/28507353

llvm-svn: 284084
2016-10-12 23:57:05 +00:00
Artem Dergachev 4eca0de7b7 [analyzer] Re-apply r283094 "Improve CloneChecker diagnostics"
The parent commit (r283092) was reverted before and now finally landed.

llvm-svn: 283661
2016-10-08 10:54:30 +00:00
Artem Dergachev 46209e1dd0 [analyzer] Re-apply r283093 "Add extra notes to ObjCDeallocChecker"
The parent commit (r283092) was reverted before and now finally landed.

llvm-svn: 283660
2016-10-08 10:53:00 +00:00
Daniel Marjamaki d99ebc03f4 [analyzer] Don't merge different return nodes in ExplodedGraph
Returns when calling an inline function should not be merged in the ExplodedGraph unless they are same.

Differential Revision: https://reviews.llvm.org/D25326

llvm-svn: 283554
2016-10-07 14:21:08 +00:00
Anton Yartsev 0509d047f4 [analyzer] Add explanation why analyzer report is not generated (fix for PR12421).
Currently if the path diagnostic consumer (e.g HTMLDiagnostics and PlistDiagnostics) do not support cross file diagnostics then the path diagnostic report is silently omitted in the case of cross file diagnostics. The patch adds a little verbosity to Clang in this case.
The patch also adds help entry for the "--analyzer-output" driver option.

llvm-svn: 283499
2016-10-06 21:42:21 +00:00
Richard Smith 0511d23aeb PR22924, PR22845, some of CWG1464: When checking the initializer for an array
new expression, distinguish between the case of a constant and non-constant
initializer. In the former case, if the bound is erroneous (too many
initializer elements, bound is negative, or allocated size overflows), reject,
and take the bound into account when determining whether we need to
default-construct any elements. In the remanining cases, move the logic to
check for default-constructibility of trailing elements into the initialization
code rather than inventing a bogus array bound, to cope with cases where the
number of initialized elements is not the same as the number of initializer
list elements (this can happen due to string literal initialization or brace
elision).

This also fixes rejects-valid and crash-on-valid errors when initializing a
new'd array of character type from a braced string literal.

llvm-svn: 283406
2016-10-05 22:41:02 +00:00
Artem Dergachev 9cb5614c29 [analyzer] Improve "Assuming..." diagnostic pieces for logical operators.
Logical short-circuit operators now act like other branch conditions.

If the symbolic value of the left-hand side is not known to be true or false
(based on the previous execution path), the "Assuming" event piece is added
in order to explain that the analyzer is adding a new assumption.

Additionally, when the assumption is made against the right-hand side of
the logical operator (i.e. when the operator itself acts as a condition
in another CFG terminator), the "Assuming..." piece is written out for the
right-hand side of the operator rather than for the whole operator.
This allows expression-specific diagnostic message text to be constructed.

Differential Revision: https://reviews.llvm.org/D25092

llvm-svn: 283302
2016-10-05 08:28:25 +00:00
Artem Dergachev 0c33406aaa [analyzer] Add "Assuming..." diagnostic pieces for unsupported conditions.
In the analyzer's path-sensitive reports, when a report goes through a branch
and the branch condition cannot be decided to be definitely true or false
(based on the previous execution path), an event piece is added that tells the
user that a new assumption is added upon the symbolic value of the branch
condition. For example, "Assuming 'a' is equal to 3".

The text of the assumption is hand-crafted in various manners depending on
the AST expression. If the AST expression is too complex and the text of
the assumption fails to be constructed, the event piece is omitted.
This causes loss of information and misunderstanding of the report.

Do not omit the event piece even if the expression is too complex;
add a piece with a generic text instead.

Differential Revision: https://reviews.llvm.org/D23300

llvm-svn: 283301
2016-10-05 08:19:49 +00:00
Vitaly Buka 1a8d52d1ae Revert "[analyzer] Improve CloneChecker diagnostics" as its depends on reverted r283092
This reverts commit r283094.

llvm-svn: 283182
2016-10-04 02:40:35 +00:00
Vitaly Buka b3814f6f38 Revert "[analyzer] Add extra notes to ObjCDeallocChecker" as its depends on reverted r283092
This reverts commit r283093.

llvm-svn: 283181
2016-10-04 02:36:58 +00:00
Daniel Marjamaki fd1b3814b3 [StaticAnalyser] Add test case to ensure that unreachable code is found.
https://reviews.llvm.org/D24905

llvm-svn: 283096
2016-10-03 09:45:35 +00:00
Daniel Marjamaki 042a3c5a2d [StaticAnalyzer] Fix UnreachableCode false positives.
When there is 'do { } while (0);' in the code the ExplodedGraph and UnoptimizedCFG did not match.

Differential Revision: https://reviews.llvm.org/D24759

llvm-svn: 283095
2016-10-03 08:28:51 +00:00
Artem Dergachev c87d2a613e [analyzer] Improve CloneChecker diagnostics
Highlight code clones referenced by the warning message with the help of
the extra notes feature recently introduced in r283092.

Change warning text to more clang-ish. Remove suggestions from the copy-paste
error checker diagnostics, because currently our suggestions are strictly 50%
wrong (we do not know which of the two code clones contains the error), and
for that reason we should not sound as if we're actually suggesting this.
Hopefully a better solution would bring them back.

Make sure the suspicious clone pair structure always mentions
the correct variable for the second clone.

Differential Revision: https://reviews.llvm.org/D24916

llvm-svn: 283094
2016-10-03 08:11:50 +00:00
Artem Dergachev 918602df8d [analyzer] Add extra notes to ObjCDeallocChecker
The report is now highlighting instance variables and properties
referenced by the warning message with the help of the
extra notes feature recently introduced in r283092.

Differential Revision: https://reviews.llvm.org/D24915

llvm-svn: 283093
2016-10-03 08:03:51 +00:00
Daniel Marjamaki 2593b402ce [StaticAnalyzer] Fix false positives for vardecls that are technically unreachable but they are needed.
Example:

    switch (x) {
      int a;  // <- This is unreachable but needed
    case 1:
      a = ...

Differential Revision: https://reviews.llvm.org/D24905

llvm-svn: 282574
2016-09-28 10:39:53 +00:00
Daniel Marjamaki 13264ebea4 [analyzer] Improve CastToStruct checker so it can also detect widening casts of struct data
Example:

struct AB {
  int A;
  int B;
};

struct ABC {
  int A;
  int B;
  int C;
};

void f() {
  struct AB Data;
  struct ABC *P = (struct ABC *)&Data;
}

Differential Revision: https://reviews.llvm.org/D23508

llvm-svn: 282411
2016-09-26 15:17:18 +00:00
Alexander Shaposhnikov a1fead293f [analyzer] Fix crash in RetainCountChecker::checkEndFunction
The class BodyFarm creates bodies for
OSAtomicCompareAndSwap*, objc_atomicCompareAndSwap*, dispatch_sync*, dispatch_once*
and for them the flag isBodyAutosynthesized is set to true.

This diff
1. makes AnalysisConsumer::HandleCode skip the autosynthesized code
2. replaces assert(LCtx->getParent()) in RetainCountChecker::checkEndFunction
by assert(!LCtx->inTopFrame()) (minor cleanup)

Test plan: make -j8 check-clang-analysis

Differential revision: https://reviews.llvm.org/D24792

llvm-svn: 282293
2016-09-23 20:49:01 +00:00
Anna Zaks c154f7bc37 [analyzer] Add a checker that detects blocks in critical sections
This checker should find the calls to blocking functions (for example: sleep, getc, fgets,read,recv etc.) inside a critical section. When sleep(x) is called while a mutex is held, other threads cannot lock the same mutex. This might take some time, leading to bad performance or even deadlock.

Example:

mutex_t m;

void f() {
  sleep(1000); // Error: sleep() while m is locked! [f() is called from foobar() while m is locked]
  // do some work
}

void foobar() {
  lock(m);
  f();
  unlock(m);
}

A patch by zdtorok (Zoltán Dániel Török)!

Differential Revision: https://reviews.llvm.org/D21506

llvm-svn: 282011
2016-09-20 20:28:50 +00:00
Gabor Horvath 7304027c6d [analyzer] Calculate extent size for memory regions allocated by new expression.
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
2016-09-19 20:39:52 +00:00
Alexander Shaposhnikov 6956d29034 [analyzer] Fix ExprEngine::VisitMemberExpr
AST may contain intermediate ParenExpr nodes
between MemberExpr and ArrayToPointerDecay.
This diff adjusts the check in ExprEngine::VisitMemberExpr accordingly.
Test plan: make -j8 check-clang-analysis

Differential revision: https://reviews.llvm.org/D24484

llvm-svn: 281373
2016-09-13 19:17:20 +00:00
Aleksei Sidorin 29afb1937b [analyzer] ExprEngine: remove second call to PreStmt<CastExpr>
This patch also introduces AnalysisOrderChecker which is intended for testing
of callback call correctness.

Differential Revision: https://reviews.llvm.org/D23804

llvm-svn: 280367
2016-09-01 13:55:38 +00:00
Aleksei Sidorin e1beaf1ee7 [analyzer] Add more FileIDs to PlistDiagnostic map to avoid assertion
Some FileIDs that may be used by PlistDiagnostics were not added while building
a list of pieces. This caused assertion violation in GetFID() function.
This patch adds some missing FileIDs to avoid the assertion. It also contains
small refactoring of PlistDiagnostics::FlushDiagnosticsImpl().

Patch by Aleksei Sidorin, Ilya Palachev.

Differential Revision: https://reviews.llvm.org/D22090

llvm-svn: 280360
2016-09-01 12:25:16 +00:00
Richard Smith 53851923d5 Fix all tests under test/CXX (and test/Analysis) to pass if clang's default
C++ language standard is not C++98.

llvm-svn: 280309
2016-08-31 23:24:08 +00:00
Devin Coughlin 184996bbb4 [analyzer] Use lazily created buffer in EmptyLocalizationContextChecker
Fix a crash when relexing the underlying memory buffer to find incorrect
arguments to NSLocalizedString(). With precompiled headers, the raw
buffer may be NULL. Instead, use the source manager to get the buffer,
which will lazily create the buffer for precompiled headers.

rdar://problem/27429091

llvm-svn: 280174
2016-08-30 23:07:14 +00:00
Artem Dergachev 5f94b089e9 [analyzer] Fix CloneDetector crash on calling methods of class templates.
If a call expression represents a method call of a class template,
and the method itself isn't templated, then the method may be considered
to be a template instantiation without template specialization arguments.

No longer crash when we could not find template specialization arguments.

Patch by Raphael Isemann!

Differential Revision: https://reviews.llvm.org/D23780

llvm-svn: 279529
2016-08-23 16:42:00 +00:00
Gabor Horvath b59b27040e Reapply "[analyzer] Added valist related checkers."
Differential Revision: https://reviews.llvm.org/D15227

llvm-svn: 279427
2016-08-22 11:21:30 +00:00
Gabor Horvath 855ad82e05 [analyzer] Correctly add assumptions based on array bounds.
Also simplify the constraints generated by the checker. 

Differential Revision: https://reviews.llvm.org/D23112

llvm-svn: 279425
2016-08-22 10:07:32 +00:00
Artem Dergachev 51b9a0e8e8 [analyzer] Make CloneDetector consider macro expansions.
So far macro-generated code was treated by the CloneDetector as normal code.
This caused that some macros where reported as false-positive clones because
large chunks of code coming from otherwise concise macro expansions were treated
as copy-pasted code.

This patch ensures that macros are treated in the same way as literals/function
calls. This prevents macros that expand into multiple statements
from being reported as clones.

Patch by Raphael Isemann!

Differential Revision: https://reviews.llvm.org/D23316

llvm-svn: 279367
2016-08-20 10:06:59 +00:00
Artem Dergachev 5183888813 [analyzer] Make CloneDetector consider template arguments.
For example, code samples `isa<Stmt>(S)' and `isa<Expr>(S)'
are no longer considered to be clones.

Patch by Raphael Isemann!

Differential Revision: https://reviews.llvm.org/D23555

llvm-svn: 279366
2016-08-20 09:57:21 +00:00
Devin Coughlin 719238b7d3 [analyzer] Weaken assertion in trackNullOrUndefValue()
We should ignore paren casts when making sure that the semantic expression
in a PseudoObjectExpr for an ObjC getter is a message send.

This has no other intended functionality change.

Adding a test for this exposed an interesting issue in another test case
that only manifests under ARC. trackNullOrUndefValue() is not properly
suppressing for nil values that are the result of nil propagation from a nil
receiver when the nil is returned from a function. I've added a FIXME for that
missing suppression.

rdar://problem/27290568

llvm-svn: 279181
2016-08-19 01:05:31 +00:00
Artem Dergachev 2fc1985db3 [analyzer] Teach CloneDetector to find clones that look like copy-paste errors.
The original clone checker tries to find copy-pasted code that is exactly
identical to the original code, up to minor details.

As an example, if the copy-pasted code has all references to variable 'a'
replaced with references to variable 'b', it is still considered to be
an exact clone.

The new check finds copy-pasted code in which exactly one variable seems
out of place compared to the original code, which likely indicates
a copy-paste error (a variable was forgotten to be renamed in one place).

Patch by Raphael Isemann!

Differential Revision: https://reviews.llvm.org/D23314

llvm-svn: 279056
2016-08-18 12:29:41 +00:00
Gabor Horvath 2402dd1e82 revert [analyzer] Added valist related checkers.
llvm-svn: 279043
2016-08-18 09:13:37 +00:00
Gabor Horvath 56e8aa535b [analyzer] Added valist related checkers.
Differential Revision: https://reviews.llvm.org/D15227

llvm-svn: 279041
2016-08-18 08:43:26 +00:00
Artem Dergachev 002981baca [analyzer] Add a checker for loss of sign or precision in integral casts.
This new checker tries to find execution paths on which implicit integral casts
cause definite loss of information: a certainly-negative integer is converted
to an unsigned integer, or an integer is definitely truncated to fit into
a smaller type.

Being implicit, such casts are likely to produce unexpected results.

Patch by Daniel Marjamäki!

Differential Revision: https://reviews.llvm.org/D13126

llvm-svn: 278941
2016-08-17 16:02:45 +00:00
Artem Dergachev cbce96c3af [analyzer] Add LocationContext information to SymbolMetadata.
Like SymbolConjured, SymbolMetadata also needs to be uniquely
identified by the moment of its birth.

Such moments are coded by the (Statement, LocationContext, Block count) triples.
Each such triple represents the moment of analyzing a statement with a certain
call backtrace, with corresponding CFG block having been entered a given amount
of times during analysis of the current code body.

The LocationContext information was accidentally omitted for SymbolMetadata,
which leads to reincarnation of SymbolMetadata upon re-entering a code body
with a different backtrace; the new symbol is incorrectly unified with
the old symbol, which leads to unsound assumptions.

Patch by Alexey Sidorin!

Differential Revision: https://reviews.llvm.org/D21978

llvm-svn: 278937
2016-08-17 15:37:52 +00:00
Saleem Abdulrasool b9250475ea StaticAnalyzer: Report found fields order in PaddingChecker
Report the found fields order in PaddingChecker.

Patch by Alexander Shaposhnikov!

llvm-svn: 278730
2016-08-15 20:16:13 +00:00
Devin Coughlin 81cc38cf9a [analyzer] Teach RetainCountChecker about CVFooRetain
Change the retain count checker to treat CoreFoundation-style "CV"-prefixed
reference types from CoreVideo similarly to CoreGraphics types. With this
change, we treat CVFooRetain() on a CVFooRef type as a retain. CVFooRelease()
APIs are annotated as consuming their parameter, so this change prevents false
positives about incorrect decrements of reference counts.

<rdar://problem/27116090>

llvm-svn: 278382
2016-08-11 18:41:29 +00:00
Artem Dergachev cad151491e [analyzer] Fix a crash in CloneDetector when calling functions by pointers.
CallExpr may have a null direct callee when the callee function is not
known in compile-time. Do not try to take callee name in this case.

Patch by Raphael Isemann!

Differential Revision: https://reviews.llvm.org/D23320

llvm-svn: 278238
2016-08-10 16:25:16 +00:00
Artem Dergachev 6a76a1639f [analyzer] Change -analyze-function to accept qualified names.
Both -analyze-function and -analyzer-display-progress now share the same
convention for naming functions, which allows discriminating between
methods with the same name in different classes, C++ overloads, and also
presents Objective-C instance and class methods in the convenient notation.

This also allows looking up the name for the particular function you're trying
to restrict analysis to in the -analyzer-display-progress output,
in case it was not instantly obvious.

Differential Revision: https://reviews.llvm.org/D22856

llvm-svn: 278018
2016-08-08 16:01:02 +00:00
Gabor Horvath c430990d0b [analyzer] Command line option to show enabled checker list.
This patch adds a command line option to list the checkers that were enabled
by analyzer-checker and not disabled by -analyzer-disable-checker.

It can be very useful to debug long command lines when it is not immediately
apparent which checkers are turned on and which checkers are turned off.

Differential Revision: https://reviews.llvm.org/D23060

llvm-svn: 278006
2016-08-08 13:41:04 +00:00
Gabor Horvath 44583ce65a [analyzer] Model base to derived casts more precisely.
Dynamic casts are handled relatively well by the static analyzer.
BaseToDerived casts however are treated conservatively. This can cause some
false positives with the NewDeleteLeaks checker.

This patch alters the behavior of BaseToDerived casts. In case a dynamic cast
would succeed use the same semantics. Otherwise fall back to the conservative
approach.

Differential Revision: https://reviews.llvm.org/D23014

llvm-svn: 277989
2016-08-08 09:22:59 +00:00
Artem Dergachev 7a0088bbae [analyzer] Make CloneDetector recognize different variable patterns.
CloneDetector should be able to detect clones with renamed variables.
However, if variables are referenced multiple times around the code sample,
the usage patterns need to be recognized.

For example, (x < y ? y : x) and (y < x ? y : x) are no longer clones,
however (a < b ? b : a) is still a clone of the former.

Variable patterns are computed and compared during a separate filtering pass.

Patch by Raphael Isemann!

Differential Revision: https://reviews.llvm.org/D22982

llvm-svn: 277757
2016-08-04 19:37:00 +00:00
Artem Dergachev 7a7004a999 [analyzer] Hotfix for buildbot failure due to unspecified triple in r277449
If a target triple is not specified, the default host triple is used,
which is not good for compiling inline assembler code.

Patch by Raphael Isemann!

llvm-svn: 277473
2016-08-02 15:16:06 +00:00
Artem Dergachev 78692ea590 [analyzer] Respect statement-specific data in CloneDetection.
So far the CloneDetector only respected the kind of each statement when
searching for clones. This patch refines the way the CloneDetector collects data
from each statement by providing methods for each statement kind,
that will read the kind-specific attributes.

For example, statements 'a < b' and 'a > b' are no longer considered to be
clones, because they are different in operation code, which is an attribute
specific to the BinaryOperator statement kind.

Patch by Raphael Isemann!

Differential Revision: https://reviews.llvm.org/D22514

llvm-svn: 277449
2016-08-02 12:21:09 +00:00
Artem Dergachev ba816326f3 [analyzer] Add basic capabilities to detect source code clones.
This patch adds the CloneDetector class which allows searching source code
for clones.

For every statement or group of statements within a compound statement,
CloneDetector computes a hash value, and finds clones by detecting
identical hash values.

This initial patch only provides a simple hashing mechanism
that hashes the kind of each sub-statement.

This patch also adds CloneChecker - a simple static analyzer checker
that uses CloneDetector to report copy-pasted code.

Patch by Raphael Isemann!

Differential Revision: https://reviews.llvm.org/D20795

llvm-svn: 276782
2016-07-26 18:13:12 +00:00