This commit fixes a bug introduced in r307903. The attribute ambiguity checker
that was introduced in r307903 checked all property attributes, which caused
errors for source-compatible properties, like:
@property (nonatomic, readonly) NSObject *prop;
@property (nonatomic, readwrite) NSObject *prop;
because the readwrite property would get implicit 'strong' attribute. The
ambiguity checker should be concerned about explicitly specified attributes
only.
rdar://33748089
llvm-svn: 311443
property and check for incompatible attributes
This commit changes the way ambiguous property synthesis (i.e. when synthesizing
a property that's declared in multiple protocols) is performed. Previously,
Clang synthesized the first property that was found. This lead to problems when
the property was synthesized in a class that conformed to two protocols that
declared that property and a second protocols had a 'readwrite' declaration -
the setter was not synthesized so the class didn't really conform to the second
protocol and user's code would crash at runtime when they would try to set the
property.
This commit ensures that a first readwrite property is selected. This is a
semantic change that changes users code in this manner:
```
@protocol P @property(readonly) int p; @end
@protocol P2 @property(readwrite) id p; @end
@interface I <P2> @end
@implementation I
@syntesize p; // Users previously got a warning here, and Clang synthesized
// readonly 'int p' here. Now Clang synthesizes readwrite 'id' p..
@end
```
To ensure that this change is safe, the warning about incompatible types is
promoted to an error when this kind of readonly/readwrite ambiguity is detected
in the @implementation. This will ensure that previous code that had this subtle
bug and ignored the warning now will fail to compile with an error, and users
should not get suprises at runtime once they resolve the error.
The commit also extends the ambiguity checker, and now it can detect conflicts
among the different property attributes. An error diagnostic is used for
conflicting attributes, to ensure that the user won't get "suprises" at runtime.
ProtocolPropertyMap is removed in favour of a a set + vector because the map's
order of iteration is non-deterministic, so it couldn't be used to select the
readwrite property.
rdar://31579994
Differential Revision: https://reviews.llvm.org/D35268
llvm-svn: 307903
When determining whether ownership was explicitly written for a
property when it is being synthesized, also consider that the original
property might have come from a protocol. Fixes rdar://problem/23931441.
llvm-svn: 255943
allow them to be written in certain kinds of user declaration and
diagnose on the use-site instead.
Also, improve and fix some diagnostics relating to __weak and
properties.
rdar://23228631
llvm-svn: 251384
Introduce the clang pragmas "assume_nonnull begin" and "assume_nonnull
end" in which we make default assumptions about the nullability of many
unannotated pointers:
- Single-level pointers are inferred to __nonnull
- NSError** in a (function or method) parameter list is inferred to
NSError * __nullable * __nullable.
- CFErrorRef * in a (function or method) parameter list is inferred
to CFErrorRef __nullable * __nullable.
- Other multi-level pointers are never inferred to anything.
Implements rdar://problem/19191042.
llvm-svn: 240156
Introduce context-sensitive, non-underscored nullability specifiers
(nonnull, nullable, null_unspecified) for Objective-C method return
types, method parameter types, and properties.
Introduce Objective-C-specific semantics, including computation of the
nullability of the result of a message send, merging of nullability
information from the @interface of a class into its @implementation,
etc .
This is the Objective-C part of rdar://problem/18868820.
llvm-svn: 240154
increasingly prevailing case to the point that new features
like ARC don't even support the fragile ABI anymore.
This required a little bit of reshuffling with exceptions
because a check was assuming that ObjCNonFragileABI was
only being set in ObjC mode, and that's actually a bit
obnoxious to do.
Most, though, it involved a perl script to translate a ton
of test cases.
Mostly no functionality change for driver users, although
there are corner cases with disabling language-specific
exceptions that we should handle more correctly now.
llvm-svn: 140957
structure to hold inferred information, then propagate each invididual
bit down to -cc1. Separate the bits of "supports weak" and "has a native
ARC runtime"; make the latter a CodeGenOption.
The tool chain is still driving this decision, because it's the place that
has the required deployment target information on Darwin, but at least it's
better-factored now.
llvm-svn: 134453
Language-design credit goes to a lot of people, but I particularly want
to single out Blaine Garst and Patrick Beard for their contributions.
Compiler implementation credit goes to Argyrios, Doug, Fariborz, and myself,
in no particular order.
llvm-svn: 133103
Alex Lorenz