Commit Graph

302 Commits

Author SHA1 Message Date
Kristof Umann 72649423c0 [analyzer][NFC] Fix inconsistent references to checkers as "checks"
Traditionally, clang-tidy uses the term check, and the analyzer uses checker,
but in the very early years, this wasn't the case, and code originating from the
early 2010's still incorrectly refer to checkers as checks.

This patch attempts to hunt down most of these, aiming to refer to checkers as
checkers, but preserve references to callback functions (like checkPreCall) as
checks.

Differential Revision: https://reviews.llvm.org/D67140

llvm-svn: 371760
2019-09-12 19:09:24 +00:00
Artem Dergachev 6b85f8e99b [analyzer] NFC: Move getStmt() and createEndOfPath() out of PathDiagnostic.
These static functions deal with ExplodedNodes which is something we don't want
the PathDiagnostic interface to know anything about, as it's planned to be
moved out of libStaticAnalyzerCore.

Differential Revision: https://reviews.llvm.org/D67382

llvm-svn: 371659
2019-09-11 20:54:21 +00:00
Artem Dergachev 8535b8ecf2 [analyzer] NFC: Re-implement stack hints as a side map in BugReport.
That's one of the few random entities in the PathDiagnostic interface that
are specific to the Static Analyzer. By moving them out we could let
everybody use path diagnostics without linking against Static Analyzer.

Differential Revision: https://reviews.llvm.org/D67381

llvm-svn: 371658
2019-09-11 20:54:17 +00:00
Artem Dergachev 2f169e7cdd [analyzer] NFC: Introduce sub-classes for path-sensitive and basic reports.
Checkers are now required to specify whether they're creating a
path-sensitive report or a path-insensitive report by constructing an
object of the respective type.

This makes BugReporter more independent from the rest of the Static Analyzer
because all Analyzer-specific code is now in sub-classes.

Differential Revision: https://reviews.llvm.org/D66572

llvm-svn: 371450
2019-09-09 20:34:40 +00:00
Artem Dergachev 630f7daf80 [analyzer] Fix analyzer warnings on analyzer.
Write tests for the actual crash that was found. Write comments and refactor
code around 17 style bugs and suppress 3 false positives.

Differential Revision: https://reviews.llvm.org/D66847

llvm-svn: 370246
2019-08-28 18:44:38 +00:00
Jonas Devlieghere 2b3d49b610 [Clang] Migrate llvm::make_unique to std::make_unique
Now that we've moved to C++14, we no longer need the llvm::make_unique
implementation from STLExtras.h. This patch is a mechanical replacement
of (hopefully) all the llvm::make_unique instances across the monorepo.

Differential revision: https://reviews.llvm.org/D66259

llvm-svn: 368942
2019-08-14 23:04:18 +00:00
Kristof Umann fc76d8551f [analyzer][NFC] Refactoring BugReporter.cpp P4.: If it can be const, make it const
When I'm new to a file/codebase, I personally find C++'s strong static type
system to be a great aid. BugReporter.cpp is still painful to read however:
function calls are made with mile long parameter lists, seemingly all of them
taken with a non-const reference/pointer. This patch fixes nothing but this:
make a few things const, and hammer it until it compiles.

Differential Revision: https://reviews.llvm.org/D65382

llvm-svn: 368735
2019-08-13 18:48:08 +00:00
Kristof Umann 6d716ef181 [analyzer][NFC] Refactoring BugReporter.cpp P3.: std::shared_pointer<PathDiagnosticPiece> -> PathDiagnosticPieceRef
find clang/ -type f -exec sed -i 's/std::shared_ptr<PathDiagnosticPiece>/PathDiagnosticPieceRef/g' {} \;
git diff -U3 --no-color HEAD^ | clang-format-diff-6.0 -p1 -i

Just as C++ is meant to be refactored, right?

Differential Revision: https://reviews.llvm.org/D65381

llvm-svn: 368717
2019-08-13 16:45:48 +00:00
Csaba Dabis 68983321cc [analyzer] MallocChecker: Prevent Integer Set Library false positives
Summary:
Integer Set Library using retain-count based allocation which is not
modeled in MallocChecker.

Reviewed By: NoQ

Tags: #clang

Differential Revision: https://reviews.llvm.org/D64680

llvm-svn: 366391
2019-07-18 00:03:55 +00:00
Rui Ueyama 49a3ad21d6 Fix parameter name comments using clang-tidy. NFC.
This patch applies clang-tidy's bugprone-argument-comment tool
to LLVM, clang and lld source trees. Here is how I created this
patch:

$ git clone https://github.com/llvm/llvm-project.git
$ cd llvm-project
$ mkdir build
$ cd build
$ cmake -GNinja -DCMAKE_BUILD_TYPE=Debug \
    -DLLVM_ENABLE_PROJECTS='clang;lld;clang-tools-extra' \
    -DCMAKE_EXPORT_COMPILE_COMMANDS=On -DLLVM_ENABLE_LLD=On \
    -DCMAKE_C_COMPILER=clang -DCMAKE_CXX_COMPILER=clang++ ../llvm
$ ninja
$ parallel clang-tidy -checks='-*,bugprone-argument-comment' \
    -config='{CheckOptions: [{key: StrictMode, value: 1}]}' -fix \
    ::: ../llvm/lib/**/*.{cpp,h} ../clang/lib/**/*.{cpp,h} ../lld/**/*.{cpp,h}

llvm-svn: 366177
2019-07-16 04:46:31 +00:00
Nathan Huckleberry 121401425d [analyzer] Support kfree in MallocChecker
Summary:
kmalloc is freed with kfree in the linux kernel. kmalloc support was
added in r204832, but kfree was not. Adding kfree fixes incorrectly
detected memory leaks.

Reviewers: NoQ, nickdesaulniers, dcoughlin, Szelethus

Reviewed By: NoQ, Szelethus

Subscribers: xazax.hun, baloghadamsoftware, szepet, a.sidorin, mikhail.ramalho, Szelethus, donat.nagy, dkrupp, Charusso, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D64030

llvm-svn: 364875
2019-07-01 23:29:10 +00:00
Kristof Umann 83cc1b35d1 [analyzer] Remove the default value arg from getChecker*Option
Since D57922, the config table contains every checker option, and it's default
value, so having it as an argument for getChecker*Option is redundant.

By the time any of the getChecker*Option function is called, we verified the
value in CheckerRegistry (after D57860), so we can confidently assert here, as
any irregularities detected at this point must be a programmer error. However,
in compatibility mode, verification won't happen, so the default value must be
restored.

This implies something else, other than adding removing one more potential point
of failure -- debug.ConfigDumper will always contain valid values for
checker/package options!

Differential Revision: https://reviews.llvm.org/D59195

llvm-svn: 361042
2019-05-17 15:52:13 +00:00
Richard Smith b9fb121a62 [c++20] Implement P1009R2: allow omitting the array bound in an array
new expression.

This was voted into C++20 as a defect report resolution, so we
retroactively apply it to all prior language modes (though it can never
actually be used before C++11 mode).

llvm-svn: 360006
2019-05-06 03:47:15 +00:00
Kristof Umann 088b1c9cdc [analyzer] Enable subcheckers to possess checker options
Under the term "subchecker", I mean checkers that do not have a checker class on
their own, like unix.MallocChecker to unix.DynamicMemoryModeling.

Since a checker object was required in order to retrieve checker options,
subcheckers couldn't possess options on their own.

This patch is also an excuse to change the argument order of getChecker*Option,
it always bothered me, now it resembles the actual command line argument
(checkername:option=value).

Differential Revision: https://reviews.llvm.org/D57579

llvm-svn: 355297
2019-03-04 00:28:16 +00:00
Kristof Umann 204bf2bbb2 [analyzer] Add CheckerManager::getChecker, make sure that a registry function registers no more than 1 checker
This patch effectively fixes the almost decade old checker naming issue.
The solution is to assert when CheckerManager::getChecker is called on an
unregistered checker, and assert when CheckerManager::registerChecker is called
on a checker that is already registered.

Differential Revision: https://reviews.llvm.org/D55429

llvm-svn: 352292
2019-01-26 21:41:50 +00:00
Kristof Umann 8fd74ebfc0 [analyzer] Reimplement dependencies between checkers
Unfortunately, up until now, the fact that certain checkers depended on one
another was known, but how these actually unfolded was hidden deep within the
implementation. For example, many checkers (like RetainCount, Malloc or CString)
modelled a certain functionality, and exposed certain reportable bug types to
the user. For example, while MallocChecker models many many different types of
memory handling, the actual "unix.MallocChecker" checker the user was exposed to
was merely and option to this modeling part.

Other than this being an ugly mess, this issue made resolving the checker naming
issue almost impossible. (The checker naming issue being that if a checker
registered more than one checker within its registry function, both checker
object recieved the same name) Also, if the user explicitly disabled a checker
that was a dependency of another that _was_ explicitly enabled, it implicitly,
without "telling" the user, reenabled it.

Clearly, changing this to a well structured, declarative form, where the
handling of dependencies are done on a higher level is very much preferred.

This patch, among the detailed things later, makes checkers declare their
dependencies within the TableGen file Checkers.td, and exposes the same
functionality to plugins and statically linked non-generated checkers through
CheckerRegistry::addDependency. CheckerRegistry now resolves these dependencies,
makes sure that checkers are added to CheckerManager in the correct order,
and makes sure that if a dependency is disabled, so will be every checker that
depends on it.

In detail:

* Add a new field to the Checker class in CheckerBase.td called Dependencies,
which is a list of Checkers.
* Move unix checkers before cplusplus, as there is no forward declaration in
tblgen :/
* Add the following new checkers:
  - StackAddrEscapeBase
  - StackAddrEscapeBase
  - CStringModeling
  - DynamicMemoryModeling (base of the MallocChecker family)
  - IteratorModeling (base of the IteratorChecker family)
  - ValistBase
  - SecuritySyntaxChecker (base of bcmp, bcopy, etc...)
  - NSOrCFErrorDerefChecker (base of NSErrorChecker and  CFErrorChecker)
  - IvarInvalidationModeling (base of IvarInvalidation checker family)
  - RetainCountBase (base of RetainCount and OSObjectRetainCount)
* Clear up and registry functions in MallocChecker, happily remove old FIXMEs.
* Add a new addDependency function to CheckerRegistry.
* Neatly format RUN lines in files I looked at while debugging.

Big thanks to Artem Degrachev for all the guidance through this project!

Differential Revision: https://reviews.llvm.org/D54438

llvm-svn: 352287
2019-01-26 20:06:54 +00:00
Kristof Umann 058a7a450a [analyzer] Supply all checkers with a shouldRegister function
Introduce the boolean ento::shouldRegister##CHECKERNAME(const LangOptions &LO)
function very similarly to ento::register##CHECKERNAME. This will force every
checker to implement this function, but maybe it isn't that bad: I saw a lot of
ObjC or C++ specific checkers that should probably not register themselves based
on some LangOptions (mine too), but they do anyways.

A big benefit of this is that all registry functions now register their checker,
once it is called, registration is guaranteed.

This patch is a part of a greater effort to reinvent checker registration, more
info here: D54438#1315953

Differential Revision: https://reviews.llvm.org/D55424

llvm-svn: 352277
2019-01-26 14:23:08 +00:00
Chandler Carruth 2946cd7010 Update the file headers across all of the LLVM projects in the monorepo
to reflect the new license.

We understand that people may be surprised that we're moving the header
entirely to discuss the new license. We checked this carefully with the
Foundation's lawyer and we believe this is the correct approach.

Essentially, all code in the project is now made available by the LLVM
project under our new license, so you will see that the license headers
include that license only. Some of our contributors have contributed
code under our old license, and accordingly, we have retained a copy of
our old license notice in the top-level files in each project and
repository.

llvm-svn: 351636
2019-01-19 08:50:56 +00:00
George Karpenkov 2c2d0b6e97 Revert "Fix failing MSan bots"
This reverts commit 2cedaaef383d8d6142046074ffebc2bb5a914778.

Revert with a fix.

llvm-svn: 351575
2019-01-18 19:24:55 +00:00
Vlad Tsyrklevich d5dd6a5fdd Fix failing MSan bots
Revert r351508-351514, this block of changes introduced a consistent
MSan failure on the sanitizer bots.

llvm-svn: 351528
2019-01-18 08:43:22 +00:00
George Karpenkov 1aa2bf8ea4 [analyzer] Extend BugType constructor to accept "SuppressOnSink" as a parameter
Differential Revision: https://reviews.llvm.org/D56884

llvm-svn: 351510
2019-01-18 03:13:01 +00:00
Kristof Umann 9af1d2d10f Revert rC349281 '[analyzer][MallocChecker][NFC] Document and reorganize some functions'
Accidentally commited earlier with the same commit title, but really it
should've been
"Revert rC349283 '[analyzer][MallocChecker] Improve warning messages on double-delete errors'"

llvm-svn: 349344
2018-12-17 12:25:48 +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
Kristof Umann a033466602 Reverting bitfield size to attempt to fix a windows buildbot
llvm-svn: 349336
2018-12-17 10:31:35 +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 76a21502fd [analyzer][NFC] Move CheckerRegistry from the Core directory to Frontend
ClangCheckerRegistry is a very non-obvious, poorly documented, weird concept.
It derives from CheckerRegistry, and is placed in lib/StaticAnalyzer/Frontend,
whereas it's base is located in lib/StaticAnalyzer/Core. It was, from what I can
imagine, used to circumvent the problem that the registry functions of the
checkers are located in the clangStaticAnalyzerCheckers library, but that
library depends on clangStaticAnalyzerCore. However, clangStaticAnalyzerFrontend
depends on both of those libraries.

One can make the observation however, that CheckerRegistry has no place in Core,
it isn't used there at all! The only place where it is used is Frontend, which
is where it ultimately belongs.

This move implies that since
include/clang/StaticAnalyzer/Checkers/ClangCheckers.h only contained a single function:

class CheckerRegistry;

void registerBuiltinCheckers(CheckerRegistry &registry);

it had to re purposed, as CheckerRegistry is no longer available to
clangStaticAnalyzerCheckers. It was renamed to BuiltinCheckerRegistration.h,
which actually describes it a lot better -- it does not contain the registration
functions for checkers, but only those generated by the tblgen files.

Differential Revision: https://reviews.llvm.org/D54436

llvm-svn: 349275
2018-12-15 16:23:51 +00:00
Raphael Isemann b23ccecbb0 Misc typos fixes in ./lib folder
Summary: Found via `codespell -q 3 -I ../clang-whitelist.txt -L uint,importd,crasher,gonna,cant,ue,ons,orign,ned`

Reviewers: teemperor

Reviewed By: teemperor

Subscribers: teemperor, jholewinski, jvesely, nhaehnle, whisperity, jfb, cfe-commits

Differential Revision: https://reviews.llvm.org/D55475

llvm-svn: 348755
2018-12-10 12:37:46 +00:00
Kristof Umann 549f9cd46f [analyzer] Evaluate all non-checker config options before analysis
In earlier patches regarding AnalyzerOptions, a lot of effort went into
gathering all config options, and changing the interface so that potential
misuse can be eliminited.

Up until this point, AnalyzerOptions only evaluated an option when it was
querried. For example, if we had a "-no-false-positives" flag, AnalyzerOptions
would store an Optional field for it that would be None up until somewhere in
the code until the flag's getter function is called.

However, now that we're confident that we've gathered all configs, we can
evaluate off of them before analysis, so we can emit a error on invalid input
even if that prticular flag will not matter in that particular run of the
analyzer. Another very big benefit of this is that debug.ConfigDumper will now
show the value of all configs every single time.

Also, almost all options related class have a similar interface, so uniformity
is also a benefit.

The implementation for errors on invalid input will be commited shorty.

Differential Revision: https://reviews.llvm.org/D53692

llvm-svn: 348031
2018-11-30 20:44:00 +00:00
Artem Dergachev e2b5438a73 [analyzer] MallocChecker: Avoid redundant transitions.
Don't generate a checker-tagged node unconditionally on the first
checkDeadSymbols callback when no pointers are tracked.

This is a tiny performance optimization; it may change the behavior slightly
by making Static Analyzer bail out on max-nodes one node later (which is good)
but any test would either break for no good reason or become useless
every time someone sneezes.

Differential Revision: https://reviews.llvm.org/D54013

llvm-svn: 347955
2018-11-30 03:52:42 +00:00
Artem Dergachev bbc6d68297 [analyzer] Fix the "Zombie Symbols" bug.
It's an old bug that consists in stale references to symbols remaining in the
GDM if they disappear from other program state sections as a result of any
operation that isn't the actual dead symbol collection. The most common example
here is:

   FILE *fp = fopen("myfile.txt", "w");
   fp = 0; // leak of file descriptor

In this example the leak were not detected previously because the symbol
disappears from the public part of the program state due to evaluating
the assignment. For that reason the checker never receives a notification
that the symbol is dead, and never reports a leak.

This patch not only causes leak false negatives, but also a number of other
problems, including false positives on some checkers.

What's worse, even though the program state contains a finite number of symbols,
the set of symbols that dies is potentially infinite. This means that is
impossible to compute the set of all dead symbols to pass off to the checkers
for cleaning up their part of the GDM.

No longer compute the dead set at all. Disallow iterating over dead symbols.
Disallow querying if any symbols are dead. Remove the API for marking symbols
as dead, as it is no longer necessary. Update checkers accordingly.

Differential Revision: https://reviews.llvm.org/D18860

llvm-svn: 347953
2018-11-30 03:27:50 +00:00
Kristof Umann 0a1f91c80c [analyzer] Restrict AnalyzerOptions' interface so that non-checker objects have to be registered
One of the reasons why AnalyzerOptions is so chaotic is that options can be
retrieved from the command line whenever and wherever. This allowed for some
options to be forgotten for a looooooong time. Have you ever heard of
"region-store-small-struct-limit"? In order to prevent this in the future, I'm
proposing to restrict AnalyzerOptions' interface so that only checker options
can be retrieved without special getters. I would like to make every option be
accessible only through a getter, but checkers from plugins are a thing, so I'll
have to figure something out for that.

This also forces developers who'd like to add a new option to register it
properly in the .def file.

This is done by

* making the third checker pointer parameter non-optional, and checked by an
  assert to be non-null.
* I added new, but private non-checkers option initializers, meant only for
  internal use,
* Renamed these methods accordingly (mind the consistent name for once with
  getBooleanOption!):
  - getOptionAsString -> getCheckerStringOption,
  - getOptionAsInteger -> getCheckerIntegerOption
* The 3 functions meant for initializing data members (with the not very
  descriptive getBooleanOption, getOptionAsString and getOptionAsUInt names)
  were renamed to be overloads of the getAndInitOption function name.
* All options were in some way retrieved via getCheckerOption. I removed it, and
  moved the logic to getStringOption and getCheckerStringOption. This did cause
  some code duplication, but that's the only way I could do it, now that checker
  and non-checker options are separated. Note that the non-checker version
  inserts the new option to the ConfigTable with the default value, but the
  checker version only attempts to find already existing entries. This is how
  it always worked, but this is clunky and I might end reworking that too, so we
  can eventually get a ConfigTable that contains the entire configuration of the
  analyzer.

Differential Revision: https://reviews.llvm.org/D53483

llvm-svn: 346113
2018-11-05 03:50:37 +00:00
Artem Dergachev 32c0c85382 [analyzer] pr39348: MallocChecker: Realize that sized delete isn't custom delete.
MallocChecker no longer thinks that operator delete() that accepts the size of
the object to delete (available since C++14 or under -fsized-deallocation)
is some weird user-defined operator. Instead, it handles it like normal delete.

Additionally, it exposes a regression in NewDelete-intersections.mm's
testStandardPlacementNewAfterDelete() test, where the diagnostic is delayed
from before the call of placement new into the code of placement new
in the header. This happens because the check for pass-into-function-after-free
for placement arguments is located in checkNewAllocator(), which happens after
the allocator is inlined, which is too late. Move this use-after-free check
into checkPreCall instead, where it works automagically because the guard
that prevents it from working is useless and can be removed as well.

This commit causes regressions under -analyzer-config
c++-allocator-inlining=false but this option is essentially unsupported
because the respective feature has been enabled by default quite a while ago.

Differential Revision: https://reviews.llvm.org/D53543

llvm-svn: 345802
2018-11-01 00:43:35 +00:00
George Karpenkov d3e7675331 [analyzer] [NFC] Change scanReachableSymbols to use ranges
Remove unused overload. Clean up some usages.

Differential Revision: https://reviews.llvm.org/D53615

llvm-svn: 345101
2018-10-23 23:12:12 +00:00
George Karpenkov c82d457db5 [analyzer] [NFC] Remove unused parameters, as found by -Wunused-parameter
Differential Revision: https://reviews.llvm.org/D52640

llvm-svn: 343353
2018-09-28 18:49:41 +00:00
Reka Kovacs bb2749a594 [analyzer] InnerPointerChecker: improve warning messages and notes.
Differential Revision: https://reviews.llvm.org/D49570

llvm-svn: 339489
2018-08-10 23:56:57 +00:00
Reka Kovacs d9f66ba340 [analyzer] InnerPointerChecker: fix displayed checker name.
For InnerPointerChecker to function properly, both the checker itself
and parts of MallocChecker that handle relevant use-after-free problems
need to be turned on. So far, the latter part has been developed within
MallocChecker's NewDelete sub-checker, often causing warnings to appear
under that name. This patch defines a new CheckKind within MallocChecker
for the inner pointer checking functionality, so that the correct name
is displayed in warnings and in the ExplodedGraph.

Tested on clang-tidy.

Differential Review: https://reviews.llvm.org/D50211

llvm-svn: 339067
2018-08-06 22:03:42 +00:00
Reka Kovacs 122171e235 [analyzer] Detect pointers escaped after ReturnStmt execution in MallocChecker.
Objects local to a function are destroyed right after the statement returning
(part of) them is executed in the analyzer. This patch enables MallocChecker to
warn in these cases.

Differential Revision: https://reviews.llvm.org/D49361

llvm-svn: 338780
2018-08-02 23:02:08 +00:00
Fangrui Song 6907ce2f8f Remove trailing space
sed -Ei 's/[[:space:]]+$//' include/**/*.{def,h,td} lib/**/*.{cpp,h}

llvm-svn: 338291
2018-07-30 19:24:48 +00:00
Reka Kovacs c74cfc4215 [analyzer] Add support for more invalidating functions in InnerPointerChecker.
According to the standard, pointers referring to the elements of a
`basic_string` may be invalidated if they are used as an argument to
any standard library function taking a reference to non-const
`basic_string` as an argument. This patch makes InnerPointerChecker warn
for these cases.

Differential Revision: https://reviews.llvm.org/D49656

llvm-svn: 338259
2018-07-30 15:43:45 +00:00
Reka Kovacs 88ad704b5b [analyzer] Rename DanglingInternalBufferChecker to InnerPointerChecker.
Differential Revision: https://reviews.llvm.org/D49553

llvm-svn: 337559
2018-07-20 15:14:49 +00:00
Reka Kovacs a14a2fed38 [analyzer] Fix memory sanitizer error in MallocChecker.
StringRef's data() returns a string that may be non-null-terminated.
Switch to using StringRefs from const char pointers in visitor notes
to avoid problems.

llvm-svn: 337474
2018-07-19 17:43:09 +00:00
Reka Kovacs 52dd98bd1e [analyzer] Fix disappearing notes in DanglingInternalBufferChecker tests
Correct a mistake of the exact same kind I am writing this checker for.

llvm-svn: 337466
2018-07-19 15:44:46 +00:00
Reka Kovacs c18ecc8489 [analyzer] Add support for more basic_string API in
DanglingInternalBufferChecker.

A pointer referring to the elements of a basic_string may be invalidated
by calling a non-const member function, except operator[], at, front,
back, begin, rbegin, end, and rend. The checker now warns if the pointer
is used after such operations.

Differential Revision: https://reviews.llvm.org/D49360

llvm-svn: 337463
2018-07-19 15:10:06 +00:00
Reka Kovacs e453e60d08 [analyzer] Highlight c_str() call in DanglingInternalBufferChecker.
Add a bug visitor to DanglingInternalBufferChecker that places a note
at the point where the dangling pointer was obtained. The visitor is
handed over to MallocChecker and attached to the report there.

Differential Revision: https://reviews.llvm.org/D48522

llvm-svn: 336495
2018-07-07 19:27:18 +00:00
Reka Kovacs e0dae15d91 [analyzer] Fix -Wcovered-switch-default warning in MallocChecker.
Remove unnecessary default case that caused buildbot failures.

llvm-svn: 336493
2018-07-07 18:37:37 +00:00
Reka Kovacs 8707cd1d1b [analyzer] Highlight container object destruction in MallocChecker.
Extend MallocBugVisitor to place a note at the point where objects with
AF_InternalBuffer allocation family are destroyed.

Differential Revision: https://reviews.llvm.org/D48521

llvm-svn: 336489
2018-07-07 17:22:45 +00:00
George Karpenkov dd18b11b8e [analyzer] [NFC] A convenient getter for getting a current stack frame
Differential Revision: https://reviews.llvm.org/D44756

llvm-svn: 335701
2018-06-27 01:51:55 +00:00
George Karpenkov 70ec1dd14d [analyzer] Do not run visitors until the fixpoint, run only once.
In the current implementation, we run visitors until the fixed point is
reached.
That is, if a visitor adds another visitor, the currently processed path
is destroyed, all diagnostics is discarded, and it is regenerated again,
until it's no longer modified.
This pattern has a few negative implications:

 - This loop does not even guarantee to terminate.
   E.g. just imagine two visitors bouncing a diagnostics around.
 - Performance-wise, e.g. for sqlite3 all visitors are being re-run at
   least 10 times for some bugs.
   We have already seen a few reports where it leads to timeouts.
 - If we want to add more computationally intense visitors, this will
   become worse.
 - From architectural standpoint, the current layout requires copying
   visitors, which is conceptually wrong, and can be annoying (e.g. no
   unique_ptr on visitors allowed).

The proposed change is a much simpler architecture: the outer loop
processes nodes upwards, and whenever the visitor is added it only
processes current nodes and above, thus guaranteeing termination.

Differential Revision: https://reviews.llvm.org/D47856

llvm-svn: 335666
2018-06-26 21:12:08 +00:00
Reka Kovacs 18775fc9b7 [analyzer] Add dangling internal buffer check.
This check will mark raw pointers to C++ standard library container internal
buffers 'released' when the objects themselves are destroyed. Such information
can be used by MallocChecker to warn about use-after-free problems.

In this first version, 'std::basic_string's are supported.

Differential Revision: https://reviews.llvm.org/D47135

llvm-svn: 334348
2018-06-09 13:03:49 +00:00