Commit Graph

1891 Commits

Author SHA1 Message Date
Balázs Kéri 7eafde981c [Checkers] Added support for freopen to StreamChecker.
Summary: Extend StreamChecker with a new evaluation function for API call 'freopen'.

Reviewers: NoQ, baloghadamsoftware, Szelethus, martong

Reviewed By: baloghadamsoftware, martong

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

Tags: #clang

Differential Revision: https://reviews.llvm.org/D69948
2019-12-05 11:08:44 +01:00
Tyker 2f96047275 [NFCI] update formating for misleading indentation warning
Reviewers: xbolva00

Reviewed By: xbolva00

Differential Revision: https://reviews.llvm.org/D70861
2019-12-03 21:21:27 +01:00
Borsik Gabor 89bc4c662c [analyzer] Add custom filter functions for GenericTaintChecker
This patch is the last of the series of patches which allow the user to
annotate their functions with taint propagation rules.

I implemented the use of the configured filtering functions. These
functions can remove taintedness from the symbols which are passed at
the specified arguments to the filters.

Differential Revision: https://reviews.llvm.org/D59516
2019-11-23 20:12:15 +01:00
Tyker b0561b3346 [NFC] Refactor representation of materialized temporaries
Summary:
this patch refactor representation of materialized temporaries to prevent an issue raised by rsmith in https://reviews.llvm.org/D63640#inline-612718

Reviewers: rsmith, martong, shafik

Reviewed By: rsmith

Subscribers: thakis, sammccall, ilya-biryukov, rnkovacs, arphaman, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D69360
2019-11-19 18:20:45 +01:00
Nico Weber c9276fbfdf Revert "[NFC] Refactor representation of materialized temporaries"
This reverts commit 08ea1ee2db.
It broke ./ClangdTests/FindExplicitReferencesTest.All
on the bots, see comments on https://reviews.llvm.org/D69360
2019-11-17 02:09:25 -05:00
Tyker 08ea1ee2db [NFC] Refactor representation of materialized temporaries
Summary:
this patch refactor representation of materialized temporaries to prevent an issue raised by rsmith in https://reviews.llvm.org/D63640#inline-612718

Reviewers: rsmith, martong, shafik

Reviewed By: rsmith

Subscribers: rnkovacs, arphaman, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D69360
2019-11-16 17:56:09 +01:00
Sylvestre Ledru 9b40a7f3bf Remove +x permission on some files 2019-11-16 14:47:20 +01:00
Artem Dergachev 57adc37fe5 [analyzer] Nullability: Don't infer nullable when passing as nullable parameter.
You can't really infer anything from that.
2019-11-08 18:27:14 -08:00
Adrian Prantl 2073dd2da7 Redeclare Objective-C property accessors inside the ObjCImplDecl in which they are synthesized.
This patch is motivated by (and factored out from)
https://reviews.llvm.org/D66121 which is a debug info bugfix. Starting
with DWARF 5 all Objective-C methods are nested inside their
containing type, and that patch implements this for synthesized
Objective-C properties.

1. SemaObjCProperty populates a list of synthesized accessors that may
   need to inserted into an ObjCImplDecl.

2. SemaDeclObjC::ActOnEnd inserts forward-declarations for all
   accessors for which no override was provided into their
   ObjCImplDecl. This patch does *not* synthesize AST function
   *bodies*. Moving that code from the static analyzer into Sema may
   be a good idea though.

3. Places that expect all methods to have bodies have been updated.

I did not update the static analyzer's inliner for synthesized
properties to point back to the property declaration (see
test/Analysis/Inputs/expected-plists/nullability-notes.m.plist), which
I believed to be more bug than a feature.

Differential Revision: https://reviews.llvm.org/D68108

rdar://problem/53782400
2019-11-08 08:23:22 -08:00
Adam Balogh 0f88caeef8 [Analyzer] Checker for Debugging Iterator Checkers
For white-box testing correct container and iterator modelling it is essential
to access the internal data structures stored for container and iterators. This
patch introduces a simple debug checkers called debug.IteratorDebugging to
achieve this.

Differential Revision: https://reviews.llvm.org/D67156
2019-11-08 08:59:50 +01:00
Artem Dergachev acac540422 [analyzer] PR41729: CStringChecker: Improve strlcat and strlcpy modeling.
- Fix false positive reports of strlcat.
- The return value of strlcat and strlcpy is now correctly calculated.
- The resulting string length of strlcat and strlcpy is now correctly
  calculated.

Patch by Daniel Krupp!

Differential Revision: https://reviews.llvm.org/D66049
2019-11-07 17:15:53 -08:00
Balázs Kéri 4980c1333f [clang][analyzer] Using CallDescription in StreamChecker.
Summary:
Recognization of function names is done now with the CallDescription
class instead of using IdentifierInfo. This means function name and
argument count is compared too.
A new check for filtering not global-C-functions was added.
Test was updated.

Reviewers: Szelethus, NoQ, baloghadamsoftware, Charusso

Reviewed By: Szelethus, NoQ, Charusso

Subscribers: rnkovacs, xazax.hun, baloghadamsoftware, szepet, a.sidorin, mikhail.ramalho, donat.nagy, Charusso, dkrupp, Szelethus, gamesh411, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D67706
2019-10-31 12:38:50 +01:00
Simon Pilgrim 2c775709f6 BlockInCriticalSectionChecker - silence static analyzer dyn_cast null dereference warning. NFCI.
The static analyzer is warning about a potential null dereference, but we should be able to use cast<> directly and if not assert will fire for us.

llvm-svn: 374717
2019-10-13 11:30:06 +00:00
Alex Langford 86c3af9029 [NFCI] Return PathSensitiveBugReport where appropriate
Some compilers have trouble converting unique_ptr<PathSensitiveBugReport> to
unique_ptr<BugReport> causing some functions to fail to compile.
Changing the return type of the functions that fail to compile does not
appear to have any issues.
I ran into this issue building with clang 3.8 on Ubuntu 16.04.

llvm-svn: 372668
2019-09-23 22:24:47 +00:00
Benjamin Kramer 1b38002c7d Move classes into anonymous namespaces. NFC.
llvm-svn: 372495
2019-09-22 09:28:47 +00:00
Kristof Umann c90fda6abe Attempt to fix a windows buildbot failure
llvm-svn: 372462
2019-09-21 07:56:40 +00:00
Kristof Umann 96be6f485c Fix a documentation error
llvm-svn: 372419
2019-09-20 18:28:04 +00:00
Kristof Umann 951cd32f4b Reland '[analyzer][MallocChecker][NFC] Document and reorganize some functions'
Differential Revision: https://reviews.llvm.org/D54823

llvm-svn: 372414
2019-09-20 17:59:20 +00:00
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 f0bb45fac3 [analyzer] NFC: Move PathDiagnostic classes to libAnalysis.
At this point the PathDiagnostic, PathDiagnosticLocation, PathDiagnosticPiece
structures no longer rely on anything specific to Static Analyzer, so we can
move them out of it for everybody to use.

PathDiagnosticConsumers are still to be handed off.

Differential Revision: https://reviews.llvm.org/D67419

llvm-svn: 371661
2019-09-11 20:54:27 +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
Gabor Borsik 080ecafdd8 Move prop-sink branch to monorepo.
llvm-svn: 371342
2019-09-08 19:23:43 +00:00
Artem Dergachev 6cee434ed1 [analyzer] Add minimal support for fix-it hints.
Allow attaching fixit hints to Static Analyzer BugReports.

Fixits are attached either to the bug report itself or to its notes
(path-sensitive event notes or path-insensitive extra notes).

Add support for fixits in text output (including the default text output that
goes without notes, as long as the fixit "belongs" to the warning).

Add support for fixits in the plist output mode.

Implement a fixit for the path-insensitive DeadStores checker. Only dead
initialization warning is currently covered.

Implement a fixit for the path-sensitive VirtualCall checker when the virtual
method is not pure virtual (in this case the "fix" is to suppress the warning
by qualifying the call).

Both fixits are under an off-by-default flag for now, because they
require more careful testing.

Differential Revision: https://reviews.llvm.org/D65182

llvm-svn: 371257
2019-09-06 20:55:29 +00:00
Artem Dergachev 2b1b4cab96 [analyzer] pr43179: Make CallDescription defensive against C variadic functions.
Most functions that our checkers react upon are not C-style variadic functions,
and therefore they have as many actual arguments as they have formal parameters.

However, it's not impossible to define a variadic function with the same name.
This will crash any checker that relies on CallDescription to check the number
of arguments but silently assumes that the number of parameters is the same.

Change CallDescription to check both the number of arguments and the number of
parameters by default.

If we're intentionally trying to match variadic functions, allow specifying
arguments and parameters separately (possibly omitting any of them).
For now we only have one CallDescription which would make use of those,
namely __builtin_va_start itself.

Differential Revision: https://reviews.llvm.org/D67019

llvm-svn: 371256
2019-09-06 20:55:24 +00:00
Benjamin Kramer 0581a44e02 Unbreak the build after r370798
llvm-svn: 370807
2019-09-03 18:24:56 +00:00
Kristof Umann 1b439659a8 [analyzer] NonNullParamChecker and CStringChecker parameter number in checker message
There are some functions which can't be given a null pointer as parameter either
because it has a nonnull attribute or it is declared to have undefined behavior
(e.g. strcmp()). Sometimes it is hard to determine from the checker message
which parameter is null at the invocation, so now this information is included
in the message.

This commit fixes https://bugs.llvm.org/show_bug.cgi?id=39358

Reviewed By: NoQ, Szelethus, whisperity

Patch by Tibor Brunner!

Differential Revision: https://reviews.llvm.org/D66333

llvm-svn: 370798
2019-09-03 17:57:01 +00:00
Kristof Umann 3b18b050b8 [analyzer] Add a checker option to detect nested dead stores
Enables the users to specify an optional flag which would warn for more dead
stores.
Previously it ignored if the dead store happened e.g. in an if condition.

if ((X = generate())) { // dead store to X
}

This patch introduces the `WarnForDeadNestedAssignments` option to the checker,
which is `false` by default - so this change would not affect any previous
users.
I have updated the code, tests and the docs as well. If I missed something, tell
me.

I also ran the analysis on Clang which generated 14 more reports compared to the
unmodified version. All of them seemed reasonable for me.

Related previous patches:
rGf224820b45c6847b91071da8d7ade59f373b96f3

Reviewers: NoQ, krememek, Szelethus, baloghadamsoftware

Reviewed By: Szelethus

Patch by Balázs Benics!

Differential Revision: https://reviews.llvm.org/D66733

llvm-svn: 370767
2019-09-03 15:22:43 +00:00
Adam Balogh 12f5c7f0c3 [Analyzer] Iterator Checkers - Make range errors and invalidated access fatal
Range errors (dereferencing or incrementing the past-the-end iterator or
decrementing the iterator of the first element of the range) and access of
invalidated iterators lead to undefined behavior. There is no point to
continue the analysis after such an error on the same execution path, but
terminate it by a sink node (fatal error). This also improves the
performance and helps avoiding double reports (e.g. in case of nested
iterators).

Differential Revision: https://reviews.llvm.org/D62893

llvm-svn: 370314
2019-08-29 09:35:47 +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
Kristof Umann 09ce8ec78a [analyzer] Avoid unnecessary enum range check on LValueToRValue casts
Summary: EnumCastOutOfRangeChecker should not perform enum range checks on LValueToRValue casts, since this type of cast does not actually change the underlying type.   Performing the unnecessary check actually triggered an assertion failure deeper in EnumCastOutOfRange for certain input (which is captured in the accompanying test code).

Reviewers: #clang, Szelethus, gamesh411, NoQ

Reviewed By: Szelethus, gamesh411, NoQ

Subscribers: NoQ, gamesh411, xazax.hun, baloghadamsoftware, szepet, a.sidorin, mikhail.ramalho, donat.nagy, dkrupp, Charusso, bjope, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D66014

llvm-svn: 369760
2019-08-23 14:21:13 +00:00
Artem Dergachev 85f7294e5a [analyzer] CastValueChecker: Correctly model results of based-to-derived casts.
Our SVal hierarchy doesn't allow modeling pointer casts as no-op. The
pointer type is instead encoded into the pointer object. Defer to our
usual pointer casting facility, SValBuilder::evalBinOp().

Fixes a crash.

llvm-svn: 369729
2019-08-23 03:24:04 +00:00
Artem Dergachev 62a76d0ae3 [analyzer] CastValueChecker: Provide DynamicTypeMap with pointer types only.
The idea to drop this requirement is good, but for now every other user
of DynamicTypeInfo expects pointer types.

Fixes a crash.

llvm-svn: 369728
2019-08-23 03:24:01 +00:00
Artem Dergachev af992e6d01 [analyzer] CastValueChecker: Avoid modeling casts between objects.
Our method only works correctly when casting a pointer to a pointer
or a reference to a reference.

Fixes a crash.

llvm-svn: 369727
2019-08-23 03:23:58 +00:00
Haojian Wu fcedc6a61b Remove an unused function, suppress -Wunused-function warning.
llvm-svn: 369629
2019-08-22 08:49:41 +00:00
Csaba Dabis 4d71600c11 [analyzer] CastValueChecker: Model isa(), isa_and_nonnull()
Summary: -

Reviewed By: NoQ

Differential Revision: https://reviews.llvm.org/D66423

llvm-svn: 369615
2019-08-22 02:57:59 +00:00
Csaba Dabis 22dc44ff89 [analyzer] CastValueChecker: Try to fix the buildbots
llvm-svn: 369609
2019-08-22 01:41:06 +00:00
Csaba Dabis e4bf456fce [analyzer] CastValueChecker: Rewrite dead header hotfix
llvm-svn: 369607
2019-08-22 00:36:42 +00:00
Csaba Dabis 0202c3596c [analyzer] CastValueChecker: Store the dynamic types and casts
Summary:
This patch introduces `DynamicCastInfo` similar to `DynamicTypeInfo` which
is stored in `CastSets` which are storing the dynamic cast informations of
objects based on memory regions. It could be used to store and check the
casts and prevent infeasible paths.

Reviewed By: NoQ

Differential Revision: https://reviews.llvm.org/D66325

llvm-svn: 369605
2019-08-22 00:20:36 +00:00
Artem Dergachev d3971fe97b [analyzer] Improve VirtualCallChecker and enable parts of it by default.
Calling a pure virtual method during construction or destruction
is undefined behavior. It's worth it to warn about it by default.
That part is now known as the cplusplus.PureVirtualCall checker.

Calling a normal virtual method during construction or destruction
may be fine, but does behave unexpectedly, as it skips virtual dispatch.
Do not warn about this by default, but let projects opt in into it
by enabling the optin.cplusplus.VirtualCall checker manually.

Give the two parts differentiated warning text:

  Before:

    Call to virtual function during construction or destruction:
    Call to pure virtual function during construction

    Call to virtual function during construction or destruction:
    Call to virtual function during destruction

  After:

    Pure virtual method call:
    Call to pure virtual method 'X::foo' during construction
        has undefined behavior

    Unexpected loss of virtual dispatch:
    Call to virtual method 'Y::bar' during construction
        bypasses virtual dispatch

Also fix checker names in consumers that support them (eg., clang-tidy)
because we now have different checker names for pure virtual calls and
regular virtual calls.

Also fix capitalization in the bug category.

Differential Revision: https://reviews.llvm.org/D64274

llvm-svn: 369449
2019-08-20 21:41:14 +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
Alex Langford 21872bc9bf [analyzer] Don't delete TaintConfig copy constructor
Summary:
Explicitly deleting the copy constructor makes compiling the function
`ento::registerGenericTaintChecker` difficult with some compilers. When we
construct an `llvm::Optional<TaintConfig>`, the optional is constructed with a
const TaintConfig reference which it then uses to invoke the deleted TaintConfig
copy constructor.

I've observered this failing with clang 3.8 on Ubuntu 16.04.

Reviewers: compnerd, Szelethus, boga95, NoQ, alexshap

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

Tags: #clang

Differential Revision: https://reviews.llvm.org/D66192

llvm-svn: 368779
2019-08-14 01:09:07 +00:00
Kristof Umann 3f7c66d551 [analyzer][NFC] Prepare visitors for different tracking kinds
When we're tracking a variable that is responsible for a null pointer
dereference or some other sinister programming error, we of course would like to
gather as much information why we think that the variable has that specific
value as possible. However, the newly introduced condition tracking shows that
tracking all values this thoroughly could easily cause an intolerable growth in
the bug report's length.

There are a variety of heuristics we discussed on the mailing list[1] to combat
this, all of them requiring to differentiate in between tracking a "regular
value" and a "condition".

This patch introduces the new `bugreporter::TrackingKind` enum, adds it to
several visitors as a non-optional argument, and moves some functions around to
make the code a little more coherent.

[1] http://lists.llvm.org/pipermail/cfe-dev/2019-June/062613.html

Differential Revision: https://reviews.llvm.org/D64270

llvm-svn: 368777
2019-08-14 00:48:57 +00:00
Kristof Umann e1117addd6 [analyzer][NFC] Make sure that the BugReport is not modified during the construction of non-visitor pieces
I feel this is kinda important, because in a followup patch I'm adding different
kinds of interestingness, and propagating the correct kind in BugReporter.cpp is
just one less thing to worry about.

Differential Revision: https://reviews.llvm.org/D65578

llvm-svn: 368755
2019-08-13 22:03:08 +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 cf229d5752 [analyzer] CastValueChecker: Model castAs(), getAs()
Summary: Thanks to Kristóf Umann for the great idea!

Reviewed By: NoQ

Differential Revision: https://reviews.llvm.org/D65889

llvm-svn: 368383
2019-08-09 02:24:42 +00:00
Adam Balogh 8557f17d88 [Analyzer] Iterator Checkers - Fix for Crash on Iterator Differences
Iterators differences were mistakenly handled as random decrements which
causes an assertion. This patch fixes this.

llvm-svn: 367802
2019-08-05 06:45:41 +00:00
Gabor Borsik 2c8098374b Buildbot fix for r367190
llvm-svn: 367193
2019-07-28 14:57:41 +00:00
Gabor Borsik 4bde15fe1e [analyzer] Add yaml parser to GenericTaintChecker
While we implemented taint propagation rules for several
builtin/standard functions, there's a natural desire for users to add
such rules to custom functions.

A series of patches will implement an option that allows users to
annotate their functions with taint propagation rules through a YAML
file. This one adds parsing of the configuration file, which may be
specified in the commands line with the analyzer config:
alpha.security.taint.TaintPropagation:Config. The configuration may
contain propagation rules, filter functions (remove taint) and sink
functions (give a warning if it gets a tainted value).

I also added a new header for future checkers to conveniently read YAML
files as checker options.

Differential Revision: https://reviews.llvm.org/D59555

llvm-svn: 367190
2019-07-28 13:38:04 +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
Fangrui Song 90e95bb289 Delete dead stores
llvm-svn: 365901
2019-07-12 14:04:34 +00:00
Csaba Dabis e856c0465d [analyzer] CastValueChecker: Remove a dump()
Summary: Fix a nit.
llvm-svn: 365590
2019-07-10 00:50:01 +00:00
Csaba Dabis 693936ab8f [analyzer] CastValueChecker: Model casts
Summary:
It models the LLVM casts:
- `cast<>`
- `dyn_cast<>`
- `cast_or_null<>`
- `dyn_cast_or_null<>`

It has a very basic support without checking the `classof()` function.

(It reapplies the reverted 'llvm-svn: 365582' patch with proper test file.)

Reviewed By: NoQ

Tags: #clang

Differential Revision: https://reviews.llvm.org/D64374

llvm-svn: 365585
2019-07-10 00:20:03 +00:00
Csaba Dabis 6a29680efb Revert "[analyzer] CastValueChecker: Model casts"
This reverts commit 27cf666443.

llvm-svn: 365584
2019-07-09 23:47:09 +00:00
Csaba Dabis 27cf666443 [analyzer] CastValueChecker: Model casts
Summary:
It models the LLVM casts:
- `cast<>`
- `dyn_cast<>`
- `cast_or_null<>`
- `dyn_cast_or_null<>`

It has a very basic support without checking the `classof()` function.

Reviewed By: NoQ

Tags: #clang

Differential Revision: https://reviews.llvm.org/D64374

llvm-svn: 365582
2019-07-09 23:33:23 +00:00
Kristof Umann 5e17ee1e35 [analyzer][IDF] Add a control dependency calculator + a new debug checker
I intend to improve the analyzer's bug reports by tracking condition
expressions.

01 bool b = messyComputation();
02 int i = 0;
03 if (b) // control dependency of the bug site, let's explain why we assume val
04        // to be true
05   10 / i; // warn: division by zero

I'll detail this heuristic in the followup patch, strictly related to this one
however:

* Create the new ControlDependencyCalculator class that uses llvm::IDFCalculator
  to (lazily) calculate control dependencies for Clang's CFG.
* A new debug checker debug.DumpControlDependencies is added for lit tests
* Add unittests

Differential Revision: https://reviews.llvm.org/D62619

llvm-svn: 365197
2019-07-05 12:17:44 +00:00
Csaba Dabis 57835bcfbd [analyzer] ReturnValueChecker: Model the guaranteed boolean return value of function calls
Summary: It models the known LLVM methods paired with their class.

Reviewers: NoQ, xazax.hun, ravikandhadai, baloghadamsoftware, Szelethus

Reviewed By: NoQ

Subscribers: dschuff, aheejin, mgorny, szepet, rnkovacs, a.sidorin,
             mikhail.ramalho, donat.nagy, dkrupp, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D63915

llvm-svn: 365103
2019-07-04 00:50:50 +00:00
Kristof Umann 71a9dc39e4 [analyzer][Dominator] Add post dominators to CFG + a new debug checker
Transform clang::DominatorTree to be able to also calculate post dominators.

* Tidy up the documentation
* Make it clang::DominatorTree template class (similarly to how
  llvm::DominatorTreeBase works), rename it to clang::CFGDominatorTreeImpl
* Clang's dominator tree is now called clang::CFGDomTree
* Clang's brand new post dominator tree is called clang::CFGPostDomTree
* Add a lot of asserts to the dump() function
* Create a new checker to test the functionality

Differential Revision: https://reviews.llvm.org/D62551

llvm-svn: 365028
2019-07-03 11:39:12 +00:00
Fangrui Song 7264a474b7 Change std::{lower,upper}_bound to llvm::{lower,upper}_bound or llvm::partition_point. NFC
llvm-svn: 365006
2019-07-03 08:13:17 +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
Artem Dergachev 512f4838c4 [analyzer] NonnullGlobalConstants: Don't be confused by a _Nonnull attribute.
The NonnullGlobalConstants checker models the rule "it doesn't make sense
to make a constant global pointer and initialize it to null"; it makes sure
that whatever it's initialized with is known to be non-null.

Ironically, annotating the type of the pointer as _Nonnull breaks the checker.

Fix handling of the _Nonnull annotation so that it was instead one more reason
to believe that the value is non-null.

Differential Revision: https://reviews.llvm.org/D63956

llvm-svn: 364869
2019-07-01 23:02:14 +00:00
Artem Dergachev 35fdec1b54 [analyzer] CStringChecker: Modernize to use CallDescriptions.
This patch uses the new CDF_MaybeBuiltin flag to handle C library functions.
It's mostly an NFC/refactoring pass, but it does fix a bug in handling memset()
when it expands to __builtin___memset_chk() because the latter has
one more argument and memset() handling code was trying to match
the exact number of arguments. Now the code is deduplicated and there's
less room for mistakes.

Differential Revision: https://reviews.llvm.org/D62557

llvm-svn: 364868
2019-07-01 23:02:10 +00:00
Artem Dergachev 5c287f751a [analyzer] DeadStores: Update the crude suppression for files generated by IIG.
They changed the comments that we were looking for.

llvm-svn: 363995
2019-06-20 22:29:40 +00:00
Artem Dergachev 44820630df [analyzer] NFC: Change evalCall() to provide a CallEvent.
This changes the checker callback signature to use the modern, easy to
use interface. Additionally, this unblocks future work on allowing
checkers to implement evalCall() for calls that don't correspond to any
call-expression or require additional information that's only available
as part of the CallEvent, such as C++ constructors and destructors.

Differential Revision: https://reviews.llvm.org/D62440

llvm-svn: 363893
2019-06-19 23:33:42 +00:00
Artem Dergachev 3707b05211 [analyzer] DeadStores: Add a crude suppression files generated by DriverKit IIG.
IIG is a replacement for MIG in DriverKit: IIG is autogenerating C++ code.
Suppress dead store warnings on such code, as the tool seems to be producing
them regularly, and the users of IIG are not in position to address these
warnings, as they don't control the autogenerated code. IIG-generated code
is identified by looking at the comments at the top of the file.

Differential Revision: https://reviews.llvm.org/D63118

llvm-svn: 363892
2019-06-19 23:33:39 +00:00
Csaba Dabis 32981637ce [analyzer] print() JSONify: Type information implementation
Summary: -

Reviewers: NoQ, xazax.hun, ravikandhadai, baloghadamsoftware, Szelethus

Reviewed By: NoQ

Subscribers: szepet, rnkovacs, a.sidorin, mikhail.ramalho, donat.nagy,
             dkrupp

Tags: #clang

Differential Revision: https://reviews.llvm.org/D62083

llvm-svn: 361979
2019-05-29 15:53:12 +00:00
Adam Balogh 9ed4b316d1 [Analyzer] Replace `CXXSelfAssignmentBRVisitor` with `NoteTags`
The `cplusplus.SelfAssignment` checker has a visitor that is added
to every `BugReport` to mark the to branch of the self assignment
operator with e.g. `rhs == *this` and `rhs != *this`. With the new
`NoteTag` feature this visitor is not needed anymore. Instead the
checker itself marks the two branches using the `NoteTag`s.

Differential Revision: https://reviews.llvm.org/D62479

llvm-svn: 361818
2019-05-28 13:07:09 +00:00
Mandeep Singh Grang 0cdc5dddca [Analyzer] Checker for non-determinism caused by iteration of unordered container of pointers
Summary: Added a checker for non-determinism caused by iterating unordered containers like std::unordered_set containing pointer elements.

Reviewers: NoQ, george.karpenkov, whisperity, Szelethus, baloghadamsoftware

Reviewed By: Szelethus

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

Tags: #clang

Differential Revision: https://reviews.llvm.org/D59279

llvm-svn: 361664
2019-05-24 19:24:08 +00:00
Artem Dergachev 4e53032d9b [CFG] NFC: Remove implicit conversion from CFGTerminator to Stmt *.
Turn it into a variant class instead. This conversion does indeed save some code
but there's a plan to add support for more kinds of terminators that aren't
necessarily based on statements, and with those in mind it becomes more and more
confusing to have CFGTerminators implicitly convertible to a Stmt *.

Differential Revision: https://reviews.llvm.org/D61814

llvm-svn: 361586
2019-05-24 01:34:22 +00:00
Adam Balogh 33160c4424 [Analyzer] Refactor begin and end symbol creation
This patch refactors begin and end symbol creation by moving symbol
conjuration into the `create...` functions. This way the functions'
responsibilities are clearer and makes possible to add more functions
handling these symbols (e.g. functions for handling the container's
size) without code multiplication.

Differential Revision: https://reviews.llvm.org/D61136

llvm-svn: 361141
2019-05-20 11:04:27 +00:00
Simon Pilgrim 3e95568dcf MIGChecker - assert we have a non-null LocationContext. NFCI.
Fixes scan-build warning.

llvm-svn: 361097
2019-05-18 11:42:19 +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
Artem Dergachev 07c7257cdc [analyzer] RetainCount: Fix os_returns_retained_on_zero with weird return types.
The checker was crashing when it was trying to assume a structure
to be null or non-null so that to evaluate the effect of the annotation.

Differential Revision: https://reviews.llvm.org/D61958

llvm-svn: 360790
2019-05-15 18:41:32 +00:00
Artem Dergachev e41ae14581 [analyzer] MIGChecker: Fix redundant semicolon.
llvm-svn: 360739
2019-05-15 01:36:41 +00:00
Artem Dergachev 70b654fa9b [analyzer] MIGChecker: Add support for os_ref_retain().
Suppress MIG checker false positives that occur when the programmer increments
the reference count before calling a MIG destructor, and the MIG destructor
literally boils down to decrementing the reference count.

Differential Revision: https://reviews.llvm.org/D61925

llvm-svn: 360737
2019-05-15 01:19:19 +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 aa9d2623a0 [analyzer][UninitializedObjectChecker] PR41741: Regard all scalar types as primitive.
https://bugs.llvm.org/show_bug.cgi?id=41741

Pretty much the same as D61246 and D61106, this time for __complex__ types. Upon
further investigation, I realized that we should regard all types
Type::isScalarType returns true for as primitive, so I merged 
isMemberPointerType(), isBlockPointerType() and isAnyComplexType()` into that
instead.

I also stumbled across yet another bug,
https://bugs.llvm.org/show_bug.cgi?id=41753, but it seems to be unrelated to
this checker.

Differential Revision: https://reviews.llvm.org/D61569

llvm-svn: 359998
2019-05-05 19:42:33 +00:00
Kristof Umann c21ec00d28 [analyzer][UninitializedObjectChecker] PR41611: Regard vector types as primitive
https://bugs.llvm.org/show_bug.cgi?id=41611

Similarly to D61106, the checker ran over an llvm_unreachable for vector types:

struct VectorSizeLong {
  VectorSizeLong() {}
  __attribute__((__vector_size__(16))) long x;
};

void __vector_size__LongTest() {
  VectorSizeLong v;
}
Since, according to my short research,

"The vector_size attribute is only applicable to integral and float scalars,
although arrays, pointers, and function return values are allowed in conjunction
with this construct."
[src: https://gcc.gnu.org/onlinedocs/gcc-4.6.1/gcc/Vector-Extensions.html#Vector-Extensions]

vector types are safe to regard as primitive.

Differential Revision: https://reviews.llvm.org/D61246

llvm-svn: 359539
2019-04-30 08:47:56 +00:00
Artem Dergachev eb71c0c961 [analyzer] SmartPtrModeling: Fix a null dereference.
Don't crash when trying to model a call in which the callee is unknown
in compile time, eg. a pointer-to-member call.

Differential Revision: https://reviews.llvm.org/D61285

llvm-svn: 359530
2019-04-30 03:00:57 +00:00
Adam Balogh d538b70b44 [Analyzer] Iterator Checkers - Do an early return after handling calls
This patch is more of a fix than a real improvement: in checkPostCall()
we should return immediately after finding the right call and handling
it. This both saves unnecessary processing and double-handling calls by
mistake.

Differential Revision: https://reviews.llvm.org/D61134

llvm-svn: 359283
2019-04-26 07:30:07 +00:00
Artem Dergachev e264ac6ae1 [analyzer] RetainCount: Allow offsets in return values.
Because RetainCountChecker has custom "local" reasoning about escapes,
it has a separate facility to deal with tracked symbols at end of analysis
and check them for leaks regardless of whether they're dead or not.
This facility iterates over the list of tracked symbols and reports
them as leaks, but it needs to treat the return value specially.

Some custom allocators tend to return the value with an offset, storing
extra metadata at the beginning of the buffer. In this case the return value
would be a non-base region. In order to avoid false positives, we still need to
find the original symbol within the return value, otherwise it'll be unable
to match it to the item in the list of tracked symbols.

Differential Revision: https://reviews.llvm.org/D60991

llvm-svn: 359263
2019-04-26 02:05:15 +00:00
Artem Dergachev ecefce6a49 [analyzer] Add FIXMEs for alpha.unix.cstring.OutOfBounds false positives.
Caused by incorrect strlcat() modeling in r332303,
cf. https://bugs.llvm.org/show_bug.cgi?id=37687#c8

llvm-svn: 359237
2019-04-25 20:30:14 +00:00
Kristof Umann f46c58e0c6 [analyzer][UninitializedObjectChecker] PR41590: Regard _Atomic types as primitive
https://bugs.llvm.org/show_bug.cgi?id=41590

For the following code snippet, UninitializedObjectChecker crashed:

struct MyAtomicInt {
  _Atomic(int) x;
  MyAtomicInt() {}
};

void entry() {
  MyAtomicInt b;
}

The problem was that _Atomic types were not regular records, unions,
dereferencable or primitive, making the checker hit the llvm_unreachable at
lib/StaticAnalyzer/Checkers/UninitializedObject/UninitializedObjectChecker.cpp:347.
The solution is to regard these types as primitive as well. The test case shows
that with this addition, not only are we able to get rid of the crash, but we
can identify x as uninitialized.

Differential Revision: https://reviews.llvm.org/D61106

llvm-svn: 359230
2019-04-25 20:00:51 +00:00
Adam Balogh d2e2e20de3 [Analyzer] Second fix for last commit for IteratorChecker
A variable was redeclared instead of assigned in an internal
block, leaving the original uninitialized. This is fixed now.

llvm-svn: 358971
2019-04-23 11:18:50 +00:00
Adam Balogh 8f8827014d [Analyzer] Fix for previous commit
A compilation warning was in my previous commit which broke the buildbot
because it is using `-Werror` for compilation. This patch fixes this
issue.

llvm-svn: 358955
2019-04-23 07:45:10 +00:00
Adam Balogh 54976e76e6 [Analyzer] Instead of recording comparisons in interator checkers do an eager state split
Currently iterator checkers record comparison of iterator positions
and process them for keeping track the distance between them (e.g.
whether a position is the same as the end position). However this
makes some processing unnecessarily complex and it is not needed at
all: we only need to keep track between the abstract symbols stored
in these iterator positions. This patch changes this and opens the
path to comparisons to the begin() and end() symbols between the
container (e.g. size, emptiness) which are stored as symbols, not
iterator positions. The functionality of the checker is unchanged.

Differential Revision: https://reviews.llvm.org/D53701

llvm-svn: 358951
2019-04-23 07:15:55 +00:00
Artem Dergachev 8c6119a442 [analyzer] PR41269: Add a bit of C++ smart pointer modeling.
Implement cplusplus.SmartPtrModeling, a new checker that doesn't
emit any warnings but models methods of smart pointers more precisely.

For now the only thing it does is make `(bool) P` return false when `P`
is a freshly moved pointer. This addresses a false positive in the
use-after-move-checker.

Differential Revision: https://reviews.llvm.org/D60796

llvm-svn: 358944
2019-04-23 02:45:42 +00:00
Kristof Umann 85e0ff752c [analyzer] Move UninitializedObjectChecker out of alpha
Moved UninitializedObjectChecker from the 'alpha.cplusplus' to the
'optin.cplusplus' package.

Differential Revision: https://reviews.llvm.org/D58573

llvm-svn: 358797
2019-04-19 23:33:50 +00:00
Artem Dergachev 0a7dd5a2a4 Reapply "[analyzer] Introduce a simplified API for adding custom path notes."
This reapplies commit r357323, fixing memory leak found by LSan.

Differential Revision: https://reviews.llvm.org/D58367

llvm-svn: 358781
2019-04-19 20:23:29 +00:00
Kristof Umann 25e592e522 [analyzer] PR41185: Fix regression where __builtin_* functions weren't recognized
For the following code snippet:

void builtin_function_call_crash_fixes(char *c) {
  __builtin_strncpy(c, "", 6);
  __builtin_memset(c, '\0', (0));
  __builtin_memcpy(c, c, 0);
}
security.insecureAPI.DeprecatedOrUnsafeBufferHandling caused a regression, as it
didn't recognize functions starting with __builtin_. Fixed exactly that.

I wanted to modify an existing test file, but the two I found didn't seem like
perfect candidates. While I was there, I prettified their RUN: lines.

Differential Revision: https://reviews.llvm.org/D59812

llvm-svn: 358609
2019-04-17 19:56:40 +00:00
Nico Weber 04347d848d Make SourceManager::createFileID(UnownedTag, ...) take a const llvm::MemoryBuffer*
Requires making the llvm::MemoryBuffer* stored by SourceManager const,
which in turn requires making the accessors for that return const
llvm::MemoryBuffer*s and updating all call sites.

The original motivation for this was to use it and fix the TODO in
CodeGenAction.cpp's ConvertBackendLocation() by using the UnownedTag
version of createFileID, and since llvm::SourceMgr* hands out a const
llvm::MemoryBuffer* this is required. I'm not sure if fixing the TODO
this way actually works, but this seems like a good change on its own
anyways.

No intended behavior change.

Differential Revision: https://reviews.llvm.org/D60247

llvm-svn: 357724
2019-04-04 21:06:41 +00:00
Artem Dergachev f7887d41cb [analyzer] When failing to evaluate a __builtin_constant_p, presume it's false.
__builtin_constant_p(x) is a compiler builtin that evaluates to 1 when
its argument x is a compile-time constant and to 0 otherwise. In CodeGen
it is simply lowered to the respective LLVM intrinsic. In the Analyzer
we've been trying to delegate modeling to Expr::EvaluateAsInt, which is
allowed to sometimes fail for no apparent reason.

When it fails, let's conservatively return false. Modeling it as false
is pretty much never wrong, and it is only required to return true
on a best-effort basis, which every user should expect.

Fixes VLAChecker false positives on code that tries to emulate
static asserts in C by constructing a VLA of dynamic size -1 under the
assumption that this dynamic size is actually a constant
in the sense of __builtin_constant_p.

Differential Revision: https://reviews.llvm.org/D60110

llvm-svn: 357557
2019-04-03 01:53:40 +00:00
Mikael Holmen 4ec931714d Fix compiler warning, remove extra ";" [NFC]
At least gcc 7.4 complained with
../tools/clang/lib/StaticAnalyzer/Checkers/Taint.cpp:26:53: warning: extra ';' [-Wpedantic]
                                        TaintTagType);
                                                     ^

llvm-svn: 357461
2019-04-02 10:01:09 +00:00
Fangrui Song 75e74e077c Range-style std::find{,_if} -> llvm::find{,_if}. NFC
llvm-svn: 357359
2019-03-31 08:48:19 +00:00
Artem Dergachev a3c9d88233 [analyzer] MIGChecker: Add support for more deallocator APIs.
Differential Revision: https://reviews.llvm.org/D59914

llvm-svn: 357335
2019-03-29 23:56:53 +00:00
Artem Dergachev 4d6fb5789f Revert "[analyzer] Introduce a simplified API for adding custom path notes."
This reverts commit r357323.

ASan leaks found by a buildbot :)

Differential Revision: https://reviews.llvm.org/D58367

llvm-svn: 357332
2019-03-29 23:11:10 +00:00
Artem Dergachev 44551cf693 [analyzer] Move taint API from ProgramState to a separate header. NFC.
It is now an inter-checker communication API, similar to the one that
connects MallocChecker/CStringChecker/InnerPointerChecker: simply a set of
setters and getters for a state trait.

Differential Revision: https://reviews.llvm.org/D59861

llvm-svn: 357326
2019-03-29 22:49:30 +00:00