Commit Graph

3222 Commits

Author SHA1 Message Date
Artem Dergachev
02955afbb4 [analyzer] pr38668: Do not attempt to cast loaded integers to floats.
This patch is a different approach to landing the reverted r349701.

It is expected to have the same object (memory region) treated as if it has
different types in different program points. The correct behavior for
RegionStore when an object is stored as an object of type T1 but loaded as
an object of type T2 is to store the object as if it has type T1 but cast it
to T2 during load.

Note that the cast here is some sort of a "reinterpret_cast" (even in C). For
instance, if you store an integer and load a float, you won't get your integer
represented as a float; instead, you will get garbage.

Admit that we cannot perform the cast and return an unknown value.

Differential Revision: https://reviews.llvm.org/D55875

rdar://problem/45062567

llvm-svn: 349984
2018-12-22 02:06:51 +00:00
George Karpenkov
d76cc59d9c [analyzer] Tests quickfix.
llvm-svn: 349943
2018-12-21 19:40:44 +00:00
George Karpenkov
255b05820c Revert "Revert rL349876 from cfe/trunk: [analyzer] Perform escaping in RetainCountChecker on type mismatch even for inlined functions"
This reverts commit b44b33f6e020a2c369da2b0c1d53cd52975f2526.

Revert the revert with the fix.

llvm-svn: 349939
2018-12-21 19:13:40 +00:00
George Karpenkov
79f0340c53 [analyzer] Correct the summary violation diagnostics for the retain count checker
It should be in the past tense.

llvm-svn: 349938
2018-12-21 19:13:28 +00:00
Simon Pilgrim
82fbb66465 Revert rL349876 from cfe/trunk: [analyzer] Perform escaping in RetainCountChecker on type mismatch even for inlined functions
The fix done in D55465 did not previously apply when the function was inlined.

rdar://46889541

Differential Revision: https://reviews.llvm.org/D55976
........
Fixes broken buildbot: http://lab.llvm.org:8011/builders/llvm-clang-x86_64-expensive-checks-win/builds/14764

llvm-svn: 349894
2018-12-21 10:11:23 +00:00
George Karpenkov
aecb371a0a [analyzer] Perform escaping in RetainCountChecker on type mismatch even for inlined functions
The fix done in D55465 did not previously apply when the function was inlined.

rdar://46889541

Differential Revision: https://reviews.llvm.org/D55976

llvm-svn: 349876
2018-12-21 02:16:36 +00:00
George Karpenkov
f508532627 [analyzer] Fix a bug in RetainCountDiagnostics while printing a note on mismatched summary in inlined functions
Previously, we were not printing a note at all if at least one of the parameters was not annotated.

rdar://46888422

Differential Revision: https://reviews.llvm.org/D55972

llvm-svn: 349875
2018-12-21 02:16:23 +00:00
Artem Dergachev
0ec95c8651 [driver] [analyzer] Fix --analyze -Xanalyzer after r349863.
If an -analyzer-config is passed through -Xanalyzer, it is not found while
looking for -Xclang.

Additionally, don't emit -analyzer-config-compatibility-mode for *every*
-analyzer-config flag we encounter; one is enough.

https://reviews.llvm.org/D55823

rdar://problem/46504165

llvm-svn: 349866
2018-12-21 01:11:21 +00:00
George Karpenkov
6d45b1f3b0 Revert "Revert "[driver] [analyzer] Fix a backward compatibility issue after r348038.""
This reverts commit 144927939587b790c0536f4ff08245043fc8d733.

Fixes the bug in the original commit.

llvm-svn: 349863
2018-12-21 00:26:19 +00:00
Artem Dergachev
212bbfad25 [analyzer] RetainCount: Suppress retain detection heuristic on some CM methods.
If it ends with "Retain" like CFRetain and returns a CFTypeRef like CFRetain,
then it is not necessarily a CFRetain. But it is indeed true that these two
return something retained.

Differential Revision: https://reviews.llvm.org/D55907

rdar://problem/39390714

llvm-svn: 349862
2018-12-21 00:18:58 +00:00
Artem Dergachev
46debda1c7 Revert "[driver] [analyzer] Fix a backward compatibility issue after r348038."
This reverts commits r349824, r349828, r349835.

More buildbot failures were noticed.

Differential Revision: https://reviews.llvm.org/D55823

rdar://problem/46504165

llvm-svn: 349843
2018-12-20 22:29:49 +00:00
Artem Dergachev
c93968a5e8 [driver] [analyzer] Fix redundant test output.
The -c flag causes a .o file to appear every time we run a test.
Remove it.

Differential Revision: https://reviews.llvm.org/D55823

rdar://problem/46504165

llvm-svn: 349835
2018-12-20 21:56:49 +00:00
Artem Dergachev
59166506bc [driver] [analyzer] Fix buildbots after r349824.
Buildbots can't find the linker, which we don't really need in our tests.

Differential Revision: https://reviews.llvm.org/D55823

rdar://problem/46504165

llvm-svn: 349828
2018-12-20 21:45:33 +00:00
Artem Dergachev
d001380a69 [driver] [analyzer] Fix a backward compatibility issue after r348038.
Since r348038 we emit an error every time an -analyzer-config option is not
found. The driver, however, suppresses this error with another flag,
-analyzer-config-compatibility-mode, so backwards compatibility is maintained,
while analyzer developers still enjoy the new typo-free experience.

The backwards compatibility turns out to be still broken when the -analyze
action is not specified; it is still possible to specify -analyzer-config
in that case. This should be fixed now.

Patch by Kristóf Umann!

Differential Revision: https://reviews.llvm.org/D55823

rdar://problem/46504165

llvm-svn: 349824
2018-12-20 21:26:40 +00:00
Aaron Ballman
2f234cbfb0 Allow direct navigation to static analysis checker documentation through SARIF exports.
This adds anchors to all of the documented checks so that you can directly link to a check by a stable name. This is useful because the SARIF file format has a field for specifying a URI to documentation for a rule and some viewers, like CodeSonar, make use of this information. These links are then exposed through the SARIF exporter.

llvm-svn: 349812
2018-12-20 20:20:20 +00:00
Artem Dergachev
b40e99af08 Revert "[analyzer] pr38668: Do not attempt to cast loaded values..."
This reverts commit r349701.

The patch was incorrect. The whole point of CastRetrievedVal()
is to handle the case in which the type from which the cast is made
(i.e., the "type" of value `V`) has nothing to do with the type of
the region it was loaded from (i.e., `R->getValueType()`).

Differential Revision: https://reviews.llvm.org/D55875

rdar://problem/45062567

llvm-svn: 349798
2018-12-20 19:36:06 +00:00
Artem Dergachev
173f55693e [analyzer] pr38668: Do not attempt to cast loaded values of non-scalar types.
It is expected to have the same object (memory region) treated as if it has
different types in different program points. The correct behavior for
RegionStore when an object is stored as an object of type T1 but loaded as
an object of type T2 is to store the object as if it has type T1 but cast it
to T2 during load.

Note that the cast here is some sort of a "reinterpret_cast" (even in C). For
instance, if you store a float and load an integer, you won't have your float
rounded to an integer; instead, you will have garbage.

Admit that we cannot perform the cast as long as types we're dealing with are
non-trivial (neither integers, nor pointers).

Of course, if the cast is not necessary (eg, T1 == T2), we can still load the
value just fine.

Differential Revision: https://reviews.llvm.org/D55875

rdar://problem/45062567

llvm-svn: 349701
2018-12-19 23:48:44 +00:00
Artem Dergachev
179064983a [analyzer] Improve modeling for returning an object from the top frame with RVO.
Static Analyzer processes the program function-by-function, sometimes diving
into other functions ("inlining" them). When an object is returned from an
inlined function, Return Value Optimization is modeled, and the returned object
is constructed at its return location directly.

When an object is returned from the function from which the analysis has started
(the top stack frame of the analysis), the return location is unknown. Model it
with a SymbolicRegion based on a conjured symbol that is specifically tagged for
that purpose, because this is generally the correct way to symbolicate
unknown locations in Static Analyzer.

Fixes leak false positives when an object is returned from top frame in C++17:
objects that are put into a SymbolicRegion-based memory region automatically
"escape" and no longer get reported as leaks. This only applies to C++17 return
values with destructors, because it produces a redundant CXXBindTemporaryExpr
in the call site, which confuses our liveness analysis. The actual fix
for liveness analysis is still pending, but it is no longer causing problems.

Additionally, re-enable temporary destructor tests in C++17.

Differential Revision: https://reviews.llvm.org/D55804

rdar://problem/46217550

llvm-svn: 349696
2018-12-19 23:14:06 +00:00
Artem Dergachev
a749d602b5 [analyzer] CStringChecker: Add the forgotten test file.
Differential Revision: https://reviews.llvm.org/D55873

rdar://problem/45366551

llvm-svn: 349683
2018-12-19 21:51:59 +00:00
Kristof Umann
09e86e77c9 Revert rC349281 '[analyzer][MallocChecker][NFC] Document and reorganize some functions'
llvm-svn: 349340
2018-12-17 12:07:57 +00:00
Artem Dergachev
ce42bd6765 [analyzer] MoveChecker: Enable by default as cplusplus.Move.
This checker warns you when you re-use an object after moving it.

Mostly developed by Peter Szecsi!

Differential Revision: https://reviews.llvm.org/D38675

llvm-svn: 349328
2018-12-17 06:30:39 +00:00
Artem Dergachev
2b500cbdf1 [analyzer] MoveChecker: Add an option to suppress warnings on locals.
Re-using a moved-from local variable is most likely a bug because there's
rarely a good motivation for not introducing a separate variable instead.
We plan to keep emitting such warnings by default.

Introduce a flag that allows disabling warnings on local variables that are
not of a known move-unsafe type. If it doesn't work out as we expected,
we'll just flip the flag.

We still warn on move-unsafe objects and unsafe operations on known move-safe
objects.

Differential Revision: https://reviews.llvm.org/D55730

llvm-svn: 349327
2018-12-17 06:19:32 +00:00
Artem Dergachev
69909540a7 Speculatively re-apply "[analyzer] MoveChecker: Add checks for dereferencing..."
This re-applies commit r349226 that was reverted in r349233 due to failures
on clang-x64-windows-msvc.

Specify enum type as unsigned for use in bit field. Otherwise overflows
may cause UB.

Differential Revision: https://reviews.llvm.org/D55388

llvm-svn: 349326
2018-12-17 05:25:23 +00:00
Artem Dergachev
dda42164ec [analyzer] Fix some expressions staying live too long. Add a debug checker.
StaticAnalyzer uses the CFG-based RelaxedLiveVariables analysis in order to,
in particular, figure out values of which expressions are still needed.
When the expression becomes "dead", it is garbage-collected during
the dead binding scan.

Expressions that constitute branches/bodies of control flow statements,
eg. `E1' in `if (C1) E1;' but not `E2' in `if (C2) { E2; }', were kept alive
for too long. This caused false positives in MoveChecker because it relies
on cleaning up loop-local variables when they go out of scope, but some of those
live-for-too-long expressions were keeping a reference to those variables.

Fix liveness analysis to correctly mark these expressions as dead.

Add a debug checker, debug.DumpLiveStmts, in order to test expressions liveness.

Differential Revision: https://reviews.llvm.org/D55566

llvm-svn: 349320
2018-12-16 23:44:06 +00:00
Kristof Umann
a82810c56b [analyzer][MallocChecker] Improve warning messages on double-delete errors
Differential Revision: https://reviews.llvm.org/D54834

llvm-svn: 349283
2018-12-15 18:41:37 +00:00
Kristof Umann
cf6bb77f65 [analyzer][MallocChecker][NFC] Document and reorganize some functions
This patch merely reorganizes some things, and features no functional change.

In detail:

* Provided documentation, or moved existing documentation in more obvious
places.
* Added dividers. (the //===----------===// thing).
* Moved getAllocationFamily, printAllocDeallocName, printExpectedAllocName and
printExpectedDeallocName in the global namespace on top of the file where
AllocationFamily is declared, as they are very strongly related.
* Moved isReleased and MallocUpdateRefState near RefState's definition for the
same reason.
* Realloc modeling was very poor in terms of variable and structure naming, as
well as documentation, so I renamed some of them and added much needed docs.
* Moved function IdentifierInfos to a separate struct, and moved isMemFunction,
isCMemFunction adn isStandardNewDelete inside it. This makes the patch affect
quite a lot of lines, should I extract it to a separate one?
* Moved MallocBugVisitor out of MallocChecker.
* Preferred switches to long else-if branches in some places.
* Neatly organized some RUN: lines.

Differential Revision: https://reviews.llvm.org/D54823

llvm-svn: 349281
2018-12-15 18:34:00 +00:00
Kristof Umann
f282d27215 [analyzer] Prefer returns values to out-params in CheckerRegistry.cpp
Renaming collectCheckers to getEnabledCheckers
Changing the functionality to acquire all enabled checkers, rather then collect
checkers for a specific CheckerOptInfo (for example, collecting all checkers for
{ "core", true }, which meant enabling all checkers from the core package, which
was an unnecessary complication).
Removing CheckerOptInfo, instead of storing whether the option was claimed via a
field, we handle errors immediately, as getEnabledCheckers can now access a
DiagnosticsEngine. Realize that the remaining information it stored is directly
accessible through AnalyzerOptions.CheckerControlList.
Fix a test with -analyzer-disable-checker -verify accidentally left in.

llvm-svn: 349274
2018-12-15 15:44:05 +00:00
Artem Dergachev
fe5be58162 Revert "[analyzer] MoveChecker: Add checks for dereferencing a smart pointer..."
This reverts commit r349226.

Fails on an MSVC buildbot.

llvm-svn: 349233
2018-12-15 02:55:55 +00:00
Artem Dergachev
46f34624d2 [analyzer] Fix unknown block calls to have zero parameters.
Right now they report to have one parameter with null decl,
because initializing an ArrayRef of pointers with a nullptr
yields an ArrayRef to an array of one null pointer.

Fixes a crash in the OSObject section of RetainCountChecker.

Differential Revision: https://reviews.llvm.org/D55671

llvm-svn: 349229
2018-12-15 02:13:26 +00:00
Artem Dergachev
0ce45fae72 [analyzer] ObjCDealloc: Fix a crash when a class attempts to deallocate a class.
The checker wasn't prepared to see the dealloc message sent to the class itself
rather than to an instance, as if it was +dealloc.

Additionally, it wasn't prepared for pure-unknown or undefined self values.
The new guard covers that as well, but it is annoying to test because
both kinds of values shouldn't really appear and we generally want to
get rid of all of them (by modeling unknown values with symbols and
by warning on use of undefined values before they are used).

The CHECK: directive for FileCheck at the end of the test looks useless,
so i removed it.

Differential Revision: https://reviews.llvm.org/D55680

llvm-svn: 349228
2018-12-15 02:09:02 +00:00
Artem Dergachev
5f500a33c1 [analyzer] ObjCContainers: Track index values.
Use trackExpressionValue() (previously known as trackNullOrUndefValue())
to track index value in the report, so that the user knew
what Static Analyzer thinks the index is.

Additionally, implement printState() to help debugging the checker later.

Differential Revision: https://reviews.llvm.org/D55458

llvm-svn: 349227
2018-12-15 02:06:13 +00:00
Artem Dergachev
ffba750a0e [analyzer] MoveChecker: Add checks for dereferencing a smart pointer after move.
Calling operator*() or operator->() on a null STL smart pointer is
undefined behavior.

Smart pointers are specified to become null after being moved from.
So we can't warn on arbitrary method calls, but these two operators
definitely make no sense.

The new bug is fatal because it's an immediate UB,
unlike other use-after-move bugs.

The work on a more generic null smart pointer dereference checker
is still pending.

Differential Revision: https://reviews.llvm.org/D55388

llvm-svn: 349226
2018-12-15 01:53:38 +00:00
Erich Keane
1b9c746034 Revert "Add extension to always default-initialize nullptr_t."
This reverts commit 46efdf2ccc2a80aefebf8433dbf9c7c959f6e629.

Richard Smith commented just after I submitted this that this is the
wrong solution.  Reverting so that I can fix differently.

llvm-svn: 349206
2018-12-14 22:41:18 +00:00
Erich Keane
07325c80d9 Add extension to always default-initialize nullptr_t.
Core issue 1013 suggests that having an uninitialied std::nullptr_t be
UB is a bit foolish, since there is only a single valid value. This DR
reports that DR616 fixes it, which does so by making lvalue-to-rvalue
conversions from nullptr_t be equal to nullptr.

However, just implementing that results in warnings/etc in many places.
In order to fix all situations where nullptr_t would seem uninitialized,
this patch instead (as an otherwise transparent extension) default
initializes uninitialized VarDecls of nullptr_t.

Differential Revision: https://reviews.llvm.org/D53713

Change-Id: I84d72a9290054fa55341e8cbdac43c8e7f25b885
llvm-svn: 349201
2018-12-14 22:22:29 +00:00
Artem Dergachev
11cadc3e6b [analyzer] MoveChecker Pt.6: Suppress the warning for the move-safe STL classes.
Some C++ standard library classes provide additional guarantees about their
state after move. Suppress warnings on such classes until a more precise
behavior is implemented. Warnings for locals are not suppressed anyway
because it's still most likely a bug.

Differential Revision: https://reviews.llvm.org/D55307

llvm-svn: 349191
2018-12-14 20:52:57 +00:00
Artem Dergachev
12f7c2bacc [analyzer] MoveChecker: Improve invalidation policies.
If a moved-from object is passed into a conservatively evaluated function
by pointer or by reference, we assume that the function may reset its state.

Make sure it doesn't apply to const pointers and const references. Add a test
that demonstrates that it does apply to rvalue references.

Additionally, make sure that the object is invalidated when its contents change
for reasons other than invalidation caused by evaluating a call conservatively.
In particular, when the object's fields are manipulated directly, we should
assume that some sort of reset may be happening.

Differential Revision: https://reviews.llvm.org/D55289

llvm-svn: 349190
2018-12-14 20:47:58 +00:00
Aaron Ballman
3ccec59ec2 Update our SARIF support from 10-10 to 11-28.
Functional changes include:

* The run.files property is now an array instead of a mapping.
* fileLocation objects now have a fileIndex property specifying the array index into run.files.
* The resource.rules property is now an array instead of a mapping.
* The result object was given a ruleIndex property that is an index into the resource.rules array.
* rule objects now have their "id" field filled out in addition to the name field.
* Updated the schema and spec version numbers to 11-28.

llvm-svn: 349188
2018-12-14 20:34:23 +00:00
Artem Dergachev
e9f1edaae1 [analyzer] RunLoopAutoreleaseLeakChecker: Come up with a test for r348822.
Statement memoization was removed in r348822 because it was noticed to cause
memory corruption. This was happening because a reference to an object
in a DenseMap was used after being invalidated by inserting a new key
into the map.

This test case crashes reliably under ASan (i.e., when Clang is built with
-DLLVM_USE_SANITIZER="Address") on at least some machines before r348822
and doesn't crash after it.

llvm-svn: 349000
2018-12-13 01:30:47 +00:00
Erich Keane
8e46c4b83f Change CallGraph print to show the fully qualified name
CallGraph previously would just show the normal name of a function,
which gets really confusing when using it on large C++ projects.  This
patch switches the printName call to a printQualifiedName, so that the
namespaces are included.

Change-Id: Ie086d863f6b2251be92109ea1b0946825b28b49a
llvm-svn: 348950
2018-12-12 18:11:36 +00:00
Erich Keane
f313ed5b7b Make clang::CallGraph look into template instantiations
Clang's CallGraph analysis doesn't use the RecursiveASTVisitor's setting
togo into template instantiations.  The result is that anything wanting
to do call graph analysis ends up missing any template function calls.

Change-Id: Ib4af44ed59f15d43f37af91622a203146a3c3189
llvm-svn: 348942
2018-12-12 17:22:52 +00:00
David Carlier
37a22ea063 [analyzer][CStringChecker] evaluate explicit_bzero
- explicit_bzero has limited scope/usage only for security/crypto purposes but is non-optimisable version of memset/0 and bzero.
- explicit_memset has similar signature and semantics as memset but is also a non-optimisable version.

Reviewers: NoQ

Reviewed By: NoQ

Differential Revision: https://reviews.llvm.org/D54592

llvm-svn: 348884
2018-12-11 18:57:07 +00:00
George Karpenkov
d1081ec508 [analyzer] Hack for backwards compatibility for options for RetainCountChecker.
To be removed once the clients update.

llvm-svn: 348821
2018-12-11 01:13:58 +00:00
George Karpenkov
ff01486753 [analyzer] Display a diagnostics when an inlined function violates its os_consumed summary
This is currently a diagnostics, but might be upgraded to an error in the future,
especially if we introduce os_return_on_success attributes.

rdar://46359592

Differential Revision: https://reviews.llvm.org/D55530

llvm-svn: 348820
2018-12-11 01:13:40 +00:00
George Karpenkov
79ed11c12e [analyzer] Resolve another bug where the name of the leaked object was not printed properly
Differential Revision: https://reviews.llvm.org/D55528

llvm-svn: 348819
2018-12-11 01:13:20 +00:00
George Karpenkov
041c9fa8ba Stop tracking retain count of OSObject after escape to void * / other primitive types
Escaping to void * / uint64_t / others non-OSObject * should stop tracking,
as such functions can have heterogeneous semantics depending on context,
and can not always be annotated.

rdar://46439133

Differential Revision: https://reviews.llvm.org/D55465

llvm-svn: 348675
2018-12-08 01:18:40 +00:00
George Karpenkov
27db33075c [analyzer] Move out tracking retain count for OSObjects into a separate checker
Allow enabling and disabling tracking of ObjC/CF objects
separately from tracking of OS objects.

Differential Revision: https://reviews.llvm.org/D55400

llvm-svn: 348638
2018-12-07 20:21:51 +00:00
Gabor Marton
30388d6485 [CTU] test/Analysis/ctu-main.cpp Attempt to fix failing windows bot
llvm-svn: 348614
2018-12-07 17:36:44 +00:00
Gabor Marton
32aff2eb79 [CTU] Add triple/lang mismatch handling
Summary:
We introduce a strict policy for C++ CTU. It can work across TUs only if
the C++ dialects are the same. We neither allow C vs C++ CTU.  We do this
because the same constructs might be represented with different properties in
the corresponding AST nodes or even the nodes might be completely different (a
struct will be RecordDecl in C, but it will be a CXXRectordDecl in C++, thus it
may cause certain assertions during cast operations).

Reviewers: xazax.hun, a_sidorin

Subscribers: rnkovacs, dkrupp, Szelethus, gamesh411, cfe-commits

Differential Revision: https://reviews.llvm.org/D55134

llvm-svn: 348610
2018-12-07 16:32:43 +00:00
Gabor Marton
ce28f5782d [CTU] test/Analysis/ctu-main.cpp Attempt to fix failing windows bot
llvm-svn: 348609
2018-12-07 16:27:31 +00:00
Gabor Marton
b87251d0bb [CTU] Add more lit tests and better error handling
Summary:
Adding some more CTU list tests. E.g. to check if a construct is unsupported.
We also slightly modify the handling of the return value of the `Import`
function from ASTImporter.

Reviewers: xazax.hun, balazske, a_sidorin

Subscribers: rnkovacs, dkrupp, Szelethus, gamesh411, cfe-commits

Differential Revision: https://reviews.llvm.org/D55131

llvm-svn: 348605
2018-12-07 16:05:58 +00:00