Commit Graph

17 Commits

Author SHA1 Message Date
Anton Yartsev b50f4ba461 [analyzer] This implements potential undefbehavior.ZeroAllocDereference checker.
TODO: support realloc(). Currently it is not possible due to the present realloc() handling. Currently RegionState is not being attached to realloc() in case of a zero Size argument. 
llvm-svn: 234889
2015-04-14 14:18:04 +00:00
Anton Yartsev 5b5c7cec08 [analyzer] Different handling of alloca().
+ separate bug report for "Free alloca()" error to be able to customize checkers responsible for this error.
+ Muted "Free alloca()" error for NewDelete checker that is not responsible for c-allocated memory, turned on for unix.MismatchedDeallocator checker.
+ RefState for alloca() - to be able to detect usage of zero-allocated memory by upcoming ZeroAllocDereference checker.
+ AF_Alloca family to handle alloca() consistently - keep proper family in RefState, handle 'alloca' by getCheckIfTracked() facility, etc.
+ extra tests.

llvm-svn: 229850
2015-02-19 13:36:20 +00:00
Anton Yartsev 6ca45c92a9 [analyzer] Move the NewDeleteLeaks checker from CplusplusAlpha to Cplusplus package.
llvm-svn: 220289
2014-10-21 12:41:36 +00:00
Jordan Rose 656fdd55dd [analyzer] Warn about double-delete in C++ at the second delete...
...rather somewhere in the destructor when we try to access something and
realize the object has already been deleted. This is necessary because
the destructor is processed before the 'delete' itself.

Patch by Karthik Bhat!

llvm-svn: 198779
2014-01-08 18:46:55 +00:00
Jordan Rose 1ccc43d50e [analyzer] Handle destructors for the argument to C++ 'delete'.
Now that the CFG includes nodes for the destructors in a delete-expression,
process them in the analyzer using the same common destructor interface
currently used for local, member, and base destructors. Also, check for when
the value is known to be null, in which case no destructor is actually run.

This does not yet handle destructors for deleted /arrays/, which may need
more CFG work. It also causes a slight regression in the location of
double delete warnings; the double delete is detected at the destructor
call, which is implicit, and so is reported on the first access within the
destructor instead of at the 'delete' statement. This will be fixed soon.

Patch by Karthik Bhat!

llvm-svn: 191381
2013-09-25 16:06:17 +00:00
Jordan Rose 867b185e63 [analyzer] Warn when using 'delete' on an uninitialized variable.
Patch by Karthik Bhat, modified slightly by me.

llvm-svn: 188043
2013-08-09 00:55:47 +00:00
Jordan Rose fbe4d85035 [analyzer] Don't inline ~shared_ptr.
The analyzer can't see the reference count for shared_ptr, so it doesn't
know whether a given destruction is going to delete the referenced object.
This leads to spurious leak and use-after-free warnings.

For now, just ban destructors named '~shared_ptr', which catches
std::shared_ptr, std::tr1::shared_ptr, and boost::shared_ptr.

PR15987

llvm-svn: 182071
2013-05-17 02:16:49 +00:00
Anton Yartsev 7af0aa86dd [analyzer] Enable NewDelete checker if NewDeleteLeaks checker is enabled.
llvm-svn: 179428
2013-04-12 23:25:40 +00:00
Anton Yartsev 8fc29db312 [analyzer] +Testcase: several used-after-free args passed to a function.
llvm-svn: 179232
2013-04-10 22:36:16 +00:00
Anton Yartsev cb2ccd6b79 [analyzer] Switched to checkPreCall interface for detecting usage after free.
Now the check is also applied to arguments for Objective-C method calls and to 'this' pointer.

llvm-svn: 179230
2013-04-10 22:21:41 +00:00
Anna Zaks a1de8567fc [analyzer] Shorten the malloc checker’s leak message
As per Ted’s suggestion!

llvm-svn: 178938
2013-04-06 00:41:36 +00:00
Jordan Rose 10ad081fc6 [analyzer] Re-enable cplusplus.NewDelete (but not NewDeleteLeaks).
As mentioned in the previous commit message, the use-after-free and
double-free warnings for 'delete' are worth enabling even while the
leak warnings still have false positives.

llvm-svn: 178891
2013-04-05 17:55:07 +00:00
Jordan Rose 26330563f2 [analyzer] Split new/delete checker into use-after-free and leaks parts.
This splits the leak-checking part of alpha.cplusplus.NewDelete into a
separate user-level checker, alpha.cplusplus.NewDeleteLeaks. All the
difficult false positives we've seen with the new/delete checker have been
spurious leak warnings; the use-after-free warnings and mismatched
deallocator warnings, while rare, have always been valid.

<rdar://problem/6194569>

llvm-svn: 178890
2013-04-05 17:55:00 +00:00
Anton Yartsev e3377fbca2 [analyzer] Reduced the unwanted correlations between checkers living inside MallocChecker.cpp
This fixes an issue pointed to by Jordan: if unix.Malloc and unix.MismatchedDeallocator are both on, then we end up still tracking leaks of memory allocated by new.
Moved the guards right before emitting the bug reports to unify and simplify the logic of handling of multiple checkers. Now all the checkers perform their checks regardless of if they were enabled, or not, and it is decided just before the emitting of the report, if it should be emitted. (idea from Anna).

Additional changes: 
improved test coverage for checker correlations;
refactoring: BadDealloc -> MismatchedDealloc

llvm-svn: 178814
2013-04-04 23:46:29 +00:00
Anton Yartsev 01acbcebbb [analyzer] Moving cplusplus.NewDelete to alpha.* for now.
llvm-svn: 178529
2013-04-02 05:59:24 +00:00
Anton Yartsev 3dfc33e3ac [analyzer] Enabled unix.Malloc checker.
+ Refactoring.

llvm-svn: 178388
2013-03-30 00:50:37 +00:00
Anton Yartsev fa637577f9 [analyzer] Tests for intersections with other checkers from MallocChecker.cpp factored out to NewDelete-intersections.mm
llvm-svn: 178387
2013-03-30 00:43:02 +00:00