Summary:
Warn if either an object or a key is nil for NSMutableDictionary setObject:forKey:.
Next steps: introduce new special issue type and model more collections
Reviewed By: ezgicicek
Differential Revision: D28189382
fbshipit-source-id: 1697829ee
Summary: Added a new issue type for sending a message to nil when its return type is non-POD. To distinguish these issues from other nullptr dereference issues, we extend the `MustBeValid` attribute to contain the reason of why an address must be valid. For now a reason can only have `SelfOfNonPODReturnMethod` as it's value, but in the future we will use it for other nullability issue types, such as nil insertion into collections.
Reviewed By: jvillard
Differential Revision: D27762333
fbshipit-source-id: 689e5a431
Summary: To support objc nil messaging for unknown function calls we prune `self` to be positive in the `normal` specification and add additional specification to handle nil case.
Reviewed By: skcho
Differential Revision: D27360757
fbshipit-source-id: 119999b30
Summary: In ObjC, when a method is called on nil, there is no NPE, the method is actually not called and the return value is 0/false/nil. There is an exception in the case where the return type is non-POD. In that case it's UB and we want to report an error.
Reviewed By: jvillard
Differential Revision: D26815687
fbshipit-source-id: 8126414ab
Summary: We were missing a part of the trace if it was going through a nil summary as the invalidation was set in the nil summary. Instead of creating a fresh value for return in the nil summary {self=0}{return=0}, we return self {self=0}{return=self}. This way we keep all the information about invalidation in the trace.
Reviewed By: jvillard
Differential Revision: D26871098
fbshipit-source-id: 6eb175e68
Summary: When a method is called in ObjC on nil, there is no NPE, the method is actually not called and the return value is 0/false/nil. (There is an exception in the case where the return type is non-POD. In that case it's UB. This will be addressed later). To implement this behaviour we add additional summary to ObjC instance methods {self = 0} {return = 0}. We also want to make sure that inferred summary will not be used in we call a method on nil, hence, we add a path condition {self > 0} to get a contradiction when needed.
Reviewed By: jvillard
Differential Revision: D26664187
fbshipit-source-id: cdac2a5bb
Summary: Added some basic examples for Objective-C we want to address next in pulse nullptr dereference analysis. In particular, we should not get a `nil` dereference error when we call a method on `nil`, except if the method returns a non-POD (Plain Old Data) type.
Reviewed By: ezgicicek
Differential Revision: D26053402
fbshipit-source-id: 66f4600c3