Commit Graph

99 Commits

Author SHA1 Message Date
Artem Dergachev 8fa639ecf0 [analyzer] Initial commit for the upcoming refactoring of the IteratorChecker.
The new checker currently contains the very core infrastructure for tracking
the state of iterator-type objects in the analyzer: relating iterators to
their containers, tracking symbolic begin and end iterator values for
containers, and solving simple equality-type constraints over iterators.
A single specific check over this infrastructure is capable of finding usage of
out-of-range iterators in some simple cases.

Patch by Ádám Balogh!

Differential revision: https://reviews.llvm.org/D32592

llvm-svn: 304160
2017-05-29 15:03:20 +00:00
Artem Dergachev 356151ff5f [analyzer] Add MisusedMovedObjectChecker for detecting use-after-move errors.
The checker currently warns on copying, moving, or calling methods on an object
that was recently std::move'd from. It understands a set of "state reset"
methods that bring a moved-from object back to a well-specified state.

Patch by Peter Szecsi!

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

llvm-svn: 298698
2017-03-24 09:52:30 +00:00
Gabor Horvath 3d57457298 [analyzer] Add checker for iterators dereferenced beyond their range.
Patch by: Adam Balogh!

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

llvm-svn: 291430
2017-01-09 09:52:32 +00:00
Devin Coughlin 8beac28564 [analyzer] Add checker modeling gtest APIs.
gtest is a widely-used unit-testing API. It provides macros for unit test
assertions:

  ASSERT_TRUE(p != nullptr);

that expand into an if statement that constructs an object representing
the result of the assertion and returns when the assertion is false:

  if (AssertionResult gtest_ar_ = AssertionResult(p == nullptr))
      ;
  else
    return ...;

Unfortunately, the analyzer does not model the effect of the constructor
precisely because (1) the copy constructor implementation is missing from the
the header (so it can't be inlined) and (2) the boolean-argument constructor
is constructed into a temporary (so the analyzer decides not to inline it since
it doesn't reliably call temporary destructors right now).

This results in false positives because the analyzer does not realize that the
the assertion must hold along the non-return path.

This commit addresses the false positives by explicitly modeling the effects
of the two un-inlined constructors on the AssertionResult state.

I've added a new package, "apiModeling", for these kinds of checkers that
model APIs but don't emit any diagnostics. I envision all the checkers in
this package always being on by default.

This addresses the false positives reported in PR30936.

Differential Revision: https://reviews.llvm.org/D27773

rdar://problem/22705813

llvm-svn: 290143
2016-12-19 22:50:31 +00:00
Artem Dergachev e69d2e47e5 [analyzer] Detect ObjC properties that are both (copy) and Mutable.
When an Objective-C property has a (copy) attribute, the default setter
for this property performs a -copy on the object assigned.

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

rdar://problem/21022397

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

llvm-svn: 289554
2016-12-13 17:19:18 +00:00
Artem Dergachev bba497fb65 [analyzer] Add StdLibraryFunctions checker.
This checker does not emit reports, however it influences the analysis
by providing complete summaries for, or otherwise improving modeling of,
various standard library functions.

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

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

llvm-svn: 284960
2016-10-24 09:41:38 +00:00
Artem Dergachev 940c770d27 [analyzer] Add NumberObjectConversion checker.
When dealing with objects that represent numbers, such as Objective-C NSNumber,
the language provides little protection from accidentally interpreting
the value of a pointer to such object as the value of the number represented
by the object. Results of such mis-interpretation may be unexpected.

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

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

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

llvm-svn: 284473
2016-10-18 11:06:28 +00:00
Artem Dergachev bb51662d8d [analyzer] Link libStaticAnalyzerCheckers to libASTMatchers.
AST matchers are useful for the analyzer's checkers.
More patches on particular checkers shall follow.

This is the first time clang binary gets linked to ASTMatchers.
The binary size increase for the clang executable would be
+0.5% in release mode, +2% in debug mode.

Differential Revision: https://reviews.llvm.org/D25429

llvm-svn: 284112
2016-10-13 11:41:12 +00:00
Anna Zaks c154f7bc37 [analyzer] Add a checker that detects blocks in critical sections
This checker should find the calls to blocking functions (for example: sleep, getc, fgets,read,recv etc.) inside a critical section. When sleep(x) is called while a mutex is held, other threads cannot lock the same mutex. This might take some time, leading to bad performance or even deadlock.

Example:

mutex_t m;

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

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

A patch by zdtorok (Zoltán Dániel Török)!

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

llvm-svn: 282011
2016-09-20 20:28:50 +00:00
Aleksei Sidorin 29afb1937b [analyzer] ExprEngine: remove second call to PreStmt<CastExpr>
This patch also introduces AnalysisOrderChecker which is intended for testing
of callback call correctness.

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

llvm-svn: 280367
2016-09-01 13:55:38 +00:00
Gabor Horvath b59b27040e Reapply "[analyzer] Added valist related checkers."
Differential Revision: https://reviews.llvm.org/D15227

llvm-svn: 279427
2016-08-22 11:21:30 +00:00
Gabor Horvath 2402dd1e82 revert [analyzer] Added valist related checkers.
llvm-svn: 279043
2016-08-18 09:13:37 +00:00
Gabor Horvath 56e8aa535b [analyzer] Added valist related checkers.
Differential Revision: https://reviews.llvm.org/D15227

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

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

Patch by Daniel Marjamäki!

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

llvm-svn: 278941
2016-08-17 16:02:45 +00:00
Artem Dergachev ba816326f3 [analyzer] Add basic capabilities to detect source code clones.
This patch adds the CloneDetector class which allows searching source code
for clones.

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

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

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

Patch by Raphael Isemann!

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

llvm-svn: 276782
2016-07-26 18:13:12 +00:00
Devin Coughlin f57f90dfd1 [analyzer] Add checker modeling potential C++ self-assignment
This checker checks copy and move assignment operators whether they are
protected against self-assignment. Since C++ core guidelines discourages
explicit checking for `&rhs==this` in general we take a different approach: in
top-frame analysis we branch the exploded graph for two cases, where &rhs==this
and &rhs!=this and let existing checkers (e.g. unix.Malloc) do the rest of the
work. It is important that we check all copy and move assignment operator in top
frame even if we checked them already since self-assignments may happen
undetected even in the same translation unit (e.g. using random indices for an
array what may or may not be the same).

This reapplies r275820 after fixing a string-lifetime issue discovered by the
bots.

A patch by Ádám Balogh!

Differential Revision: https://reviews.llvm.org/D19311

llvm-svn: 276365
2016-07-21 23:42:31 +00:00
Devin Coughlin d2387432bb Revert "[analyzer] Add checker modeling potential C++ self-assignment"
This reverts commit r275820. It is failing on the bots.

llvm-svn: 275880
2016-07-18 18:57:50 +00:00
Devin Coughlin eea0737a34 [analyzer] Add checker modeling potential C++ self-assignment
This checker checks copy and move assignment operators whether they are
protected against self-assignment. Since C++ core guidelines discourages
explicit checking for `&rhs==this` in general we take a different approach: in
top-frame analysis we branch the exploded graph for two cases, where &rhs==this
and &rhs!=this and let existing checkers (e.g. unix.Malloc) do the rest of the
work. It is important that we check all copy and move assignment operator in top
frame even if we checked them already since self-assignments may happen
undetected even in the same translation unit (e.g. using random indices for an
array what may or may not be the same).

A patch by Ádám Balogh!

Differential Revision: https://reviews.llvm.org/D19311

llvm-svn: 275820
2016-07-18 17:23:30 +00:00
Devin Coughlin 160f19cdda [analyzer] Add checker to verify the correct usage of the MPI API
This commit adds a static analysis checker to verify the correct usage of the MPI API in C
and C++. This version updates the reverted r271981 to fix a memory corruption found by the
ASan bots.

Three path-sensitive checks are included:
- Double nonblocking: Double request usage by nonblocking calls without intermediate wait
- Missing wait: Nonblocking call without matching wait.
- Unmatched wait: Waiting for a request that was never used by a nonblocking call

Examples of how to use the checker can be found at https://github.com/0ax1/MPI-Checker

A patch by Alexander Droste!

Reviewers: zaks.anna, dcoughlin

Differential Revision: http://reviews.llvm.org/D21081

llvm-svn: 272529
2016-06-13 03:22:41 +00:00
Devin Coughlin fd6d0821eb Revert "[analyzer] Reapply r271907 (2nd try)."
Even with the fix in r271981, ASan is finding a stack use after return.

This reverts commits r271977 and r271981.

llvm-svn: 271984
2016-06-07 05:37:02 +00:00
Devin Coughlin cc1fb35705 [analyzer] Reapply r271907 (2nd try).
Second try at reapplying
"[analyzer] Add checker for correct usage of MPI API in C and C++."

Special thanks to Dan Liew for helping test the fix for the template
specialization compiler error with gcc.

The original patch is by Alexander Droste!

Differential Revision: http://reviews.llvm.org/D12761

llvm-svn: 271977
2016-06-07 04:23:08 +00:00
Devin Coughlin 917a42d8b5 Revert "Reapply "[analyzer] Add checker for correct usage of MPI API in C and C++.""
This reverts commit r271914. It is still breaking bots.

llvm-svn: 271920
2016-06-06 18:29:43 +00:00
Devin Coughlin 8027409be4 Reapply "[analyzer] Add checker for correct usage of MPI API in C and C++."
Reapply r271907 with a fix for the compiler error with gcc about specializing
clang::ento::ProgramStateTrait in a different namespace.

Differential Revision: http://reviews.llvm.org/D12761

llvm-svn: 271914
2016-06-06 18:08:35 +00:00
Devin Coughlin cc73e62ebe Revert "[analyzer] Add checker for correct usage of MPI API in C and C++."
This reverts commit r271907. It broke a bunch of bots with compile errors
about specializations in different namespaces.

llvm-svn: 271909
2016-06-06 17:01:08 +00:00
Devin Coughlin 83ccd1a994 [analyzer] Add checker for correct usage of MPI API in C and C++.
This commit adds a static analysis checker to check for the correct usage of the
MPI API in C and C++.

3 path-sensitive checks are included:

- Double nonblocking: Double request usage by nonblocking calls
  without intermediate wait.
- Missing wait: Nonblocking call without matching wait.
- Unmatched wait: Waiting for a request that was never used by a
  nonblocking call.

Examples of how to use the checker can be found
at https://github.com/0ax1/MPI-Checker

Reviewers: zaks.anna

A patch by Alexander Droste!

Differential Revision: http://reviews.llvm.org/D12761

llvm-svn: 271907
2016-06-06 16:47:16 +00:00
Chih-Hung Hsieh a9ad1552ab [analyzer] Move Checkers.inc to clang/include/...
Simplify sharing of Checkers.inc with other files like ClangTidy.cpp.

Differential Revision: http://reviews.llvm.org/19393

llvm-svn: 267832
2016-04-28 01:09:09 +00:00
Devin Coughlin eb6673cfed [analyzer] Detect duplicate [super dealloc] calls
Add an alpha path checker that warns about duplicate calls to [super dealloc].
This will form the foundation of a checker that will detect uses of
'self' after calling [super dealloc].

Part of rdar://problem/6953275.

Based on a patch by David Kilzer!

Differential Revision: http://reviews.llvm.org/D5238

llvm-svn: 261545
2016-02-22 17:56:24 +00:00
Ben Craig 97c191c473 [PATCH] Adding checker to detect excess padding in records
The intent of this checker is to generate a report for any class / structure
that could reduce its padding by reordering the fields.  This results in a very
noisy checker.  To reduce the noise, this checker will currently only warn when
the number of bytes over "optimal" is more than 24.  This value is configurable
with -analyzer-config performance.Padding:AllowedPad=N.  Small values of
AllowedPad have the potential to generate hundreds of reports, and gigabytes
of HTML reports.

The checker searches for padding violations in two main ways.  First, it goes
record by record.  A report is generated if the fields could be reordered in a
way that reduces the padding by more than AllowedPad bytes.  Second, the
checker will generate a report if an array will cause more than AllowedPad
padding bytes to be generated.

The record checker currently skips many ABI specific cases.  Classes with base
classes are skipped because base class tail padding is ABI specific.  Bitfields
are just plain hard, and duplicating that code seems like a bad idea.  VLAs are
both uncommon and non-trivial to fix.

The array checker isn't very thorough right now.  It only checks to see if the
element type's fields could be reordered, and it doesn't recursively check to
see if any of the fields' fields could be reordered.  At some point in the
future, it would be nice if "arrays" could also look at array new usages and
malloc patterns that appear to be creating arrays.

llvm-svn: 255545
2015-12-14 21:38:59 +00:00
Yury Gribov 22b4164e7d [analyzer] Add VforkChecker to find unsafe code in vforked process.
This checker looks for unsafe constructs in vforked process:
function calls (excluding whitelist), memory write and returns.
This was originally motivated by a vfork-related bug in xtables package.

Patch by Yury Gribov.

Differential revision: http://reviews.llvm.org/D14014

llvm-svn: 252285
2015-11-06 11:16:31 +00:00
Gabor Horvath dce40c518d [Static Analyzer] General type checker based on dynamic type information.
Differential Revision: http://reviews.llvm.org/D12973

llvm-svn: 248041
2015-09-18 21:15:37 +00:00
Gabor Horvath c0c7a5df6e [Static Analyzer] Merge the Objective-C Generics Checker into Dynamic Type Propagation checker.
Differential Revision: http://reviews.llvm.org/D12381

llvm-svn: 247532
2015-09-13 23:02:24 +00:00
Gabor Horvath 28690925ed [Static Analyzer] Checks to catch nullability related issues.
Differential Revision: http://reviews.llvm.org/D11468

llvm-svn: 246105
2015-08-26 23:17:43 +00:00
Gabor Horvath 717b51c821 [Static Analyzer] Add checker to catch lightweight generics related type errors in Objective-C.
Differential Revision: http://reviews.llvm.org/D11427

llvm-svn: 245646
2015-08-21 00:18:28 +00:00
NAKAMURA Takumi a0d39dd80a clangStaticAnalyzerCheckers: Update libdesp.
llvm-svn: 245145
2015-08-15 01:56:49 +00:00
Anna Zaks e5d74caf2a [analyzer] Add checkers for OS X / iOS localizability issues
Add checkers that detect code-level localizability issues for OS X / iOS:
  - A path sensitive checker that warns about uses of non-localized
    NSStrings passed to UI methods expecting localized strings.
  - A syntax checker that warns against not including a comment in
    NSLocalizedString macros.

A patch by Kulpreet Chilana!

(This is the second attempt with the compilation issue on Windows and
the random test failures resolved.)

llvm-svn: 245093
2015-08-14 20:22:22 +00:00
Anna Zaks 9592df7901 Revert "[analyzer] Add checkers for OS X / iOS localizability issues"
This reverts commit fc885033a30b6e30ccf82398ae7c30e646727b10.

Revert all localization checker commits until the proper fix is implemented.

llvm-svn: 244394
2015-08-08 04:53:04 +00:00
Anna Zaks 38b496a05d [analyzer] Add checkers for OS X / iOS localizability issues
Add checkers that detect code-level localizability issues for OS X / iOS:
 - A path sensitive checker that warns about uses of non-localized
 NSStrings passed to UI methods expecting localized strings.
 - A syntax checker that warns against not including a comment in
 NSLocalizedString macros.

A patch by Kulpreet Chilana!

llvm-svn: 244389
2015-08-08 01:49:26 +00:00
Jordan Rose dc352bb82b [analyzer] Check for code testing a variable for 0 after using it as a denominator.
This new checker, alpha.core.TestAfterDivZero, catches issues like this:

  int sum = ...
  int avg = sum / count; // potential division by zero...
  if (count == 0) { ... } // ...caught here

Because the analyzer does not necessarily explore /all/ paths through a program,
this check is restricted to only work on zero checks that immediately follow a
division operation (/ % /= %=). This could later be expanded to handle checks
dominated by a division operation but not necessarily in the same CFG block.

Patch by Anders Rönnholm! (with very minor modifications by me)

llvm-svn: 212731
2014-07-10 16:10:52 +00:00
NAKAMURA Takumi 9698686505 [CMake] Use LINK_LIBS instead of target_link_libraries().
llvm-svn: 202238
2014-02-26 06:41:29 +00:00
NAKAMURA Takumi 7da9487dd4 [CMake] Get rid of explicit dependencies to include/clang/*.inc and introduce CLANG_TABLEGEN_TARGETS.
This does;
  - clang_tablegen() adds each tblgen'd target to global property CLANG_TABLEGEN_TARGETS as list.
  - List of targets is added to LLVM_COMMON_DEPENDS.
  - all clang libraries and targets depend on generated headers.

You might wonder this would be regression, but in fact, this is little loss.
  - Almost all of clang libraries depend on tblgen'd files and clang-tblgen.
  - clang-tblgen may cause short stall-out but doesn't cause unconditional rebuild.
  - Each library's dependencies to tblgen'd files might vary along headers' structure.
    It made hard to track and update *really optimal* dependencies.

Each dependency to intrinsics_gen and ClangSACheckers is left as DEPENDS.

llvm-svn: 201842
2014-02-21 07:59:59 +00:00
NAKAMURA Takumi 413496f89b [CMake] Prune stray entries in add_dependencies(). target_link_libraries() implies it.
llvm-svn: 200531
2014-01-31 11:19:04 +00:00
Ted Kremenek 776409286b [analyzer] Remove IdempotentOperations checker.
This checker has not been updated to work with interprocedural analysis,
and actually contains both logical correctness issues but also
memory bugs.  We can resuscitate it from version control once there
is focused interest in making it a real viable checker again.

llvm-svn: 198476
2014-01-04 05:52:11 +00:00
NAKAMURA Takumi 65d42bcc2b [CMake] clang/lib: Satisfy dependencies to add *actually used* libraries on target_link_libraries() and LLVM_LINK_COMPONENTS.
I will prune redundant dependencies later.

llvm-svn: 196800
2013-12-09 19:04:43 +00:00
Jordan Rose 51327f9237 [analyzer] Add IdenticalExprChecker, to find copy-pasted code.
This syntactic checker looks for expressions on both sides of comparison
operators that are structurally the same. As a special case, the
floating-point idiom "x != x" for "isnan(x)" is left alone.

Currently this only checks comparison operators, but in the future we could
extend this to include logical operators or chained if-conditionals.

Checker by Per Viberg!

llvm-svn: 194236
2013-11-08 01:15:39 +00:00
Jordan Rose 6feda28756 [analyzer] Replace bug category magic strings with shared constants, take 2.
Re-commit r191910 (reverted in r191936) with layering violation fixed, by
moving the bug categories to StaticAnalyzerCore instead of ...Checkers.

llvm-svn: 191937
2013-10-04 00:25:24 +00:00
Ted Kremenek 8671acba95 [analyzer] Add experimental option "leak-diagnostics-reference-allocation".
This is an opt-in tweak for leak diagnostics to reference the allocation
site if the diagnostic consumer only wants a pithy amount of information,
and not the entire path.

This is a strawman enhancement that I expect to see some experimentation
with over the next week, and can go away if we don't want it.

Currently it is only used by RetainCountChecker, but could be used
by MallocChecker if and when we decide this should stay in.

llvm-svn: 179634
2013-04-16 21:44:22 +00:00
Ted Kremenek eb5f089ce1 Properly sort list.
llvm-svn: 179627
2013-04-16 21:10:09 +00:00
Anna Zaks ef89339986 [analyzer] Rename AttrNonNullChecker -> NonNullParamChecker
llvm-svn: 176755
2013-03-09 03:23:14 +00:00
Ted Kremenek e71ce97689 Alphabetize source files, just like they have been before.
llvm-svn: 169318
2012-12-04 22:17:32 +00:00
Jordan Rose 3c2f65a73d [analyzer] New checker for missing super calls in UIViewController subclasses.
This is a syntactic checker aimed at helping iOS programmers correctly
subclass and override the methods of UIViewController. While this should
eventually be covered by the 'objc_requires_super' attribute, this
checker can be used with the existing iOS SDKs without any header changes.

This new checker is currently named 'alpha.osx.cocoa.MissingSuperCall'.
Patch by Julian Mayer!

llvm-svn: 166993
2012-10-30 01:21:35 +00:00