Change the analyzer's modeling of memcpy to be more precise when copying into fixed-size
array fields. With this change, instead of invalidating the entire containing region the
analyzer now invalidates only offsets for the array itself when it can show that the
memcpy stays within the bounds of the array.
This addresses false positive memory leak warnings of the kind reported by
krzysztof in https://llvm.org/bugs/show_bug.cgi?id=22954
(This is the second attempt, now with assertion failures resolved.)
A patch by Pierre Gousseau!
Differential Revision: http://reviews.llvm.org/D12571
llvm-svn: 248516
StringRefs always point to immutable memory so the const doesn't add value
here. Also quiets clang's -Wrange-loop-analysis which warns about the implicit
copying.
llvm-svn: 248496
This patch ignores malloc-overflow bug in two cases:
Case1:
x = a/b; where n < b
malloc (x*n); Then x*n will not overflow.
Case2:
x = a; // when 'a' is a known value.
malloc (x*n);
Also replaced isa with dyn_cast.
Reject multiplication by zero cases in MallocOverflowSecurityChecker
Currently MallocOverflowSecurityChecker does not catch cases like:
malloc(n * 0 * sizeof(int));
This patch rejects such cases.
Two test cases added. malloc-overflow2.c has an example inspired from a code
in linux kernel where the current checker flags a warning while it should not.
A patch by Aditya Kumar!
Differential Revision: http://reviews.llvm.org/D9924
llvm-svn: 248446
Various improvements to the localization checker:
* Adjusted copy to be consistent with diagnostic text in other Apple
API checkers.
* Added in ~150 UIKit / AppKit methods that require localized strings in
UnlocalizedStringsChecker.
* UnlocalizedStringChecker now checks for UI methods up the class hierarchy and
UI methods that conform for a certain Objective-C protocol.
* Added in alpha version of PluralMisuseChecker and some regression tests. False
positives are still not ideal.
(This is the second attempt, with the memory issues on Linux resolved.)
A patch by Kulpreet Chilana!
Differential Revision: http://reviews.llvm.org/D12417
llvm-svn: 248432
Various improvements to the localization checker:
* Adjusted copy to be consistent with diagnostic text in other Apple
API checkers.
* Added in ~150 UIKit / AppKit methods that require localized strings in
UnlocalizedStringsChecker.
* UnlocalizedStringChecker now checks for UI methods up the class hierarchy and
UI methods that conform for a certain Objective-C protocol.
* Added in alpha version of PluralMisuseChecker and some regression tests. False
positives are still not ideal.
A patch by Kulpreet Chilana!
Differential Revision: http://reviews.llvm.org/D12417
llvm-svn: 248350
Currently realloc(ptr, 0) is treated as free() which seems to be not correct. C
standard (N1570) establishes equivalent behavior for malloc(0) and realloc(ptr,
0): "7.22.3 Memory management functions calloc, malloc, realloc: If the size of
the space requested is zero, the behavior is implementation-defined: either a
null pointer is returned, or the behavior is as if the size were some nonzero
value, except that the returned pointer shall not be used to access an object."
The patch equalizes the processing of malloc(0) and realloc(ptr,0). The patch
also enables unix.Malloc checker to detect references to zero-allocated memory
returned by realloc(ptr,0) ("Use of zero-allocated memory" warning).
A patch by Антон Ярцев!
Differential Revision: http://reviews.llvm.org/D9040
llvm-svn: 248336
The analyzer trims unnecessary nodes from the exploded graph before reporting
path diagnostics. However, in some cases it can trim all nodes (including the
error node), leading to an assertion failure (see
https://llvm.org/bugs/show_bug.cgi?id=24184).
This commit addresses the issue by adding two new APIs to CheckerContext to
explicitly create error nodes. Unless the client provides a custom tag, these
APIs tag the node with the checker's tag -- preventing it from being trimmed.
The generateErrorNode() method creates a sink error node, while
generateNonFatalErrorNode() creates an error node for a path that should
continue being explored.
The intent is that one of these two methods should be used whenever a checker
creates an error node.
This commit updates the checkers to use these APIs. These APIs
(unlike addTransition() and generateSink()) do not take an explicit Pred node.
This is because there are not any error nodes in the checkers that were created
with an explicit different than the default (the CheckerContext's Pred node).
It also changes generateSink() to require state and pred nodes (previously
these were optional) to reduce confusion.
Additionally, there were several cases where checkers did check whether a
generated node could be null; we now explicitly check for null in these places.
This commit also includes a test case written by Ying Yi as part of
http://reviews.llvm.org/D12163 (that patch originally addressed this issue but
was reverted because it introduced false positive regressions).
Differential Revision: http://reviews.llvm.org/D12780
llvm-svn: 247859
In Objective-C, method calls with nil receivers are essentially no-ops. They
do not fault (although the returned value may be garbage depending on the
declared return type and architecture). Programmers are aware of this
behavior and will complain about a false alarm when the analyzer
diagnoses API violations for method calls when the receiver is known to
be nil.
Rather than require each individual checker to be aware of this behavior
and suppress a warning when the receiver is nil, this commit
changes ExprEngineObjC so that VisitObjCMessage skips calling checker
pre/post handlers when the receiver is definitely nil. Instead, it adds a
new event, ObjCMessageNil, that is only called in that case.
The CallAndMessageChecker explicitly cares about this case, so I've changed it
to add a callback for ObjCMessageNil and moved the logic in PreObjCMessage
that handles nil receivers to the new callback.
rdar://problem/18092611
Differential Revision: http://reviews.llvm.org/D12123
llvm-svn: 247653
This patch depends on r246688 (D12341).
The goal is to make LLVM generate different code for these functions for a target that
has cheap branches (see PR23827 for more details):
int foo();
int normal(int x, int y, int z) {
if (x != 0 && y != 0) return foo();
return 1;
}
int crazy(int x, int y) {
if (__builtin_unpredictable(x != 0 && y != 0)) return foo();
return 1;
}
Differential Revision: http://reviews.llvm.org/D12458
llvm-svn: 246699
Change the analyzer's modeling of memcpy to be more precise when copying into fixed-size
array fields. With this change, instead of invalidating the entire containing region the
analyzer now invalidates only offsets for the array itself when it can show that the
memcpy stays within the bounds of the array.
This addresses false positive memory leak warnings of the kind reported by
krzysztof in https://llvm.org/bugs/show_bug.cgi?id=22954
A patch by Pierre Gousseau!
Differential Revision: http://reviews.llvm.org/D11832
llvm-svn: 246345
Adds parsing/sema analysis/serialization/deserialization for array sections in OpenMP constructs (introduced in OpenMP 4.0).
Currently it is allowed to use array sections only in OpenMP clauses that accepts list of expressions.
Differential Revision: http://reviews.llvm.org/D10732
llvm-svn: 245937
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
Make the copy/move ctors defaulted in the base class and make the
derived classes final to avoid any intermediate hierarchy slicing if
these types were further derived.
llvm-svn: 244979
(return by value is in ExprEngine::processPointerEscapedOnBind and any
other call to the scanReachableSymbols function template used there)
Protect the special members in the base class to avoid slicing, and make
derived classes final so these special members don't accidentally become
public on an intermediate base which would open up the possibility of
slicing again.
llvm-svn: 244975
After r244870 flush() will only compare two null pointers and return,
doing nothing but wasting run time. The call is not required any more
as the stream and its SmallString are always in sync.
Thanks to David Blaikie for reviewing.
llvm-svn: 244928
This reverts commit fc885033a30b6e30ccf82398ae7c30e646727b10.
Revert all localization checker commits until the proper fix is implemented.
llvm-svn: 244394
This reverts commit 57a46a75b408245cf4154a838fe13ad702065745.
Revert all localization checker commits until the proper fix is implemented.
llvm-svn: 244393
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
The ObjCSuperCallChecker issues alarms for various Objective-C APIs that require
a subclass to call to its superclass's version of a method when overriding it.
So, for example, it raises an alarm when the -viewDidLoad method in a subclass
of UIViewController does not call [super viewDidLoad].
This patch fixes a false alarm where the analyzer erroneously required the
implementation of the superclass itself (e.g., UIViewController) to call
super.
rdar://problem/18416944
Differential Revision: http://reviews.llvm.org/D11842
llvm-svn: 244386
Craig Topper