https://gcc.gnu.org/onlinedocs/gcc/Typeof.html
Differences from the GCC extension:
* __auto_type is also permitted in C++ (but only in places where
it could appear in C), allowing its use in headers that might
be shared across C and C++, or used from C++98
* __auto_type can be combined with a declarator, as with C++ auto
(for instance, "__auto_type *p")
* multiple variables can be declared in a single __auto_type
declaration, with the C++ semantics (the deduced type must be
the same in each case)
This patch also adds a missing restriction on applying typeof to
a bit-field, which GCC has historically rejected in C (due to
lack of clarity as to whether the operand should be promoted).
The same restriction also applies to __auto_type in C (in both
GCC and Clang).
This also fixes PR25449.
Patch by Nicholas Allegra!
llvm-svn: 252690
Introduce co- and contra-variance for Objective-C type parameters,
which allows us to express that (for example) an NSArray is covariant
in its type parameter. This means that NSArray<NSMutableString *> * is
a subtype of NSArray<NSString *> *, which is expected of the immutable
Foundation collections.
Type parameters can be annotated with __covariant or __contravariant
to make them co- or contra-variant, respectively. This feature can be
detected by __has_feature(objc_generics_variance). Implements
rdar://problem/20217490.
llvm-svn: 241549
Warn in cases where one has provided redundant protocol qualification
that might be a typo for a specialization, e.g., NSArray<NSObject>,
which is pointless (NSArray declares that it conforms to NSObject) and
is likely to be a typo for NSArray<NSObject *>, i.e., an array of
NSObject pointers. This warning is very narrow, only applying when the
base type being qualified is parameterized, has the same number of
parameters as their are protocols listed, all of the names can also
refer to types (including Objective-C class types, of course), and at
least one of those types is an Objective-C class (making this a typo
for a missing '*'). The limitations are partly for performance reasons
(we don't want to do redundant name lookup unless we really need to),
and because we want the warning to apply in very limited cases to
limit false positives.
Part of rdar://problem/6294649.
llvm-svn: 241547
Teach C++'s tentative parsing to handle specializations of Objective-C
class types (e.g., NSArray<NSString *>) as well as Objective-C
protocol qualifiers (id<NSCopying>) by extending type-annotation
tokens to handle this case. As part of this, remove Objective-C
protocol qualifiers from the declaration specifiers, which never
really made sense: instead, provide Sema entry points to make them
part of the type annotation token. Among other things, this properly
diagnoses bogus types such as "<NSCopying> id" which should have been
written as "id <NSCopying>".
Implements template instantiation support for, e.g., NSArray<T>*
in C++. Note that parameterized classes are not templates in the C++
sense, so that cannot (for example) be used as a template argument for
a template template parameter. Part of rdar://problem/6294649.
llvm-svn: 241545
When messaging a method that was defined in an Objective-C class (or
category or extension thereof) that has type parameters, substitute
the type arguments for those type parameters. Similarly, substitute
into property accesses, instance variables, and other references.
This includes general infrastructure for substituting the type
arguments associated with an ObjCObject(Pointer)Type into a type
referenced within a particular context, handling all of the
substitutions required to deal with (e.g.) inheritance involving
parameterized classes. In cases where no type arguments are available
(e.g., because we're messaging via some unspecialized type, id, etc.),
we substitute in the type bounds for the type parameters instead.
Example:
@interface NSSet<T : id<NSCopying>> : NSObject <NSCopying>
- (T)firstObject;
@end
void f(NSSet<NSString *> *stringSet, NSSet *anySet) {
[stringSet firstObject]; // produces NSString*
[anySet firstObject]; // produces id<NSCopying> (the bound)
}
When substituting for the type parameters given an unspecialized
context (i.e., no specific type arguments were given), substituting
the type bounds unconditionally produces type signatures that are too
strong compared to the pre-generics signatures. Instead, use the
following rule:
- In covariant positions, such as method return types, replace type
parameters with “id” or “Class” (the latter only when the type
parameter bound is “Class” or qualified class, e.g,
“Class<NSCopying>”)
- In other positions (e.g., parameter types), replace type
parameters with their type bounds.
- When a specialized Objective-C object or object pointer type
contains a type parameter in its type arguments (e.g.,
NSArray<T>*, but not NSArray<NSString *> *), replace the entire
object/object pointer type with its unspecialized version (e.g.,
NSArray *).
llvm-svn: 241543
Objective-C type arguments can be provided in angle brackets following
an Objective-C interface type. Syntactically, this is the same
position as one would provide protocol qualifiers (e.g.,
id<NSCopying>), so parse both together and let Sema sort out the
ambiguous cases. This applies both when parsing types and when parsing
the superclass of an Objective-C class, which can now be a specialized
type (e.g., NSMutableArray<T> inherits from NSArray<T>).
Check Objective-C type arguments against the type parameters of the
corresponding class. Verify the length of the type argument list and
that each type argument satisfies the corresponding bound.
Specializations of parameterized Objective-C classes are represented
in the type system as distinct types. Both specialized types (e.g.,
NSArray<NSString *> *) and unspecialized types (NSArray *) are
represented, separately.
llvm-svn: 241542
Produce type parameter declarations for Objective-C type parameters,
and attach lists of type parameters to Objective-C classes,
categories, forward declarations, and extensions as
appropriate. Perform semantic analysis of type bounds for type
parameters, both in isolation and across classes/categories/extensions
to ensure consistency.
Also handle (de-)serialization of Objective-C type parameter lists,
along with sundry other things one must do to add a new declaration to
Clang.
Note that Objective-C type parameters are typedef name declarations,
like typedefs and C++11 type aliases, in support of type erasure.
Part of rdar://problem/6294649.
llvm-svn: 241541
Addresses a conflict with glibc's __nonnull macro by renaming the type
nullability qualifiers as follows:
__nonnull -> _Nonnull
__nullable -> _Nullable
__null_unspecified -> _Null_unspecified
This is the major part of rdar://problem/21530726, but does not yet
provide the Darwin-specific behavior for the old names.
llvm-svn: 240596
...instead of as a special case in ParseObjCTypeName with lots of
duplicated logic. Besides being a nice refactoring, this also allows
"- (instancetype __nonnull)self" in addition to "- (nonnull instancetype)self".
rdar://problem/19924646
llvm-svn: 240188
Adds a new warning (under -Wnullability-completeness) that complains
about pointer, block pointer, or member pointer declarations that have
not been annotated with nullability information (directly or inferred)
within a header that contains some nullability annotations. This is
intended to be used to help maintain the completeness of nullability
information within a header that has already been audited.
Note that, for performance reasons, this warning will underrepresent
the number of non-annotated pointers in the case where more than one
pointer is seen before the first nullability type specifier, because
we're only tracking one piece of information per header. Part of
rdar://problem/18868820.
llvm-svn: 240158
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
'null_resettable' properties are those whose getters return nonnull
but whose setters take nil, to "reset" the property to some
default. Implements rdar://problem/19051334.
llvm-svn: 240155
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
in the context of the container itself.
Otherwise we will emit 'unavailable' errors when referencing an unavailable super class
even though the subclass is also marked 'unavailable'.
rdar://20598702
llvm-svn: 235276
in debugger mode) to accept @import declarations
and pass them to the debugger.
In the preprocessor, accept import declarations
if the debugger is enabled, but don't actually
load the module, just pass the import path on to
the preprocessor callbacks.
In the Objective-C parser, if it sees an import
declaration in statement context (usual for LLDB),
ignore it and return a NullStmt.
llvm-svn: 223855
Sema::ActOnIdExpression to use the new functionality.
Among other things, this allows recovery in several cases where it
wasn't possible before (e.g. correcting a mistyped static_cast<>).
llvm-svn: 222464
than one method with mismatched type of same selector name.
clang issues a warning to point this out since it may cause
undefined behavior. There are cases though that some APIs
don't care about user methods and such warnings are perceived as
noise. This patch allows users to add paren delimiters around
selector name to turn off such warnings. So, @selector((save:)) will
turn off the warning. It also provides 'fixit' so user knows
what to do. // rdar://16458579
llvm-svn: 211611
1) Teach ExpectAndConsume() to emit expected and expected-after diagnostics
using the generic diagnostic descriptions added in r197972, eliminating another
set of trivial err_expected_* variations while maintaining existing behaviour.
2) Lift SkipUntil() recovery out of ExpectAndConsume(). The Expect/Consume
family of functions are primitive parser operations that now have the
well-defined property of operating on single tokens. Factoring out recovery
exposes opportunities for more consistent and tailored error recover at the
call sites instead of just relying on a bottled SkipUntil formula.
llvm-svn: 198270
Introduce proper facilities to render token spellings using the diagnostic
formatter.
Replaces most of the hard-coded diagnostic messages related to expected tokens,
which all shared the same semantics but had to be multiply defined due to
variations in token order or quote marks.
The associated parser changes are largely mechanical but they expose
commonality in whole chunks of the parser that can now be factored away.
This commit uses C++11 typed enums along with a speculative legacy fallback
until the transition is complete.
Requires corresponding changes in LLVM r197895.
llvm-svn: 197972
module. Use the marker to diagnose cases where we try to transition between
submodules when not at the top level (most likely because a closing brace was
missing at the end of a header file, but is also possible if submodule headers
attempt to do something fundamentally non-modular, like our .def files).
llvm-svn: 195543
declared in a typedef declaraton used as super
class of an ObjC class. Curretnly, these protocols
are dropped from the class hierarchy. Test shows that
it is now included. // rdar://15051465
llvm-svn: 191395
- factor the name construction part out from constructSetterName
- rename constructSetterName to the more appropriate constructSetterSelector
no functionality change intended.
rdar://problem/14035789
llvm-svn: 183582
When we are consuming the current token just to enter a new token stream, we push
the current token in the back of the stream so that we get it again.
Unfortunately this had the effect where if the current token is a code-completion one,
we would code-complete once during consuming it and another time after the stream ended.
Fix this by making sure that, in this case, ConsumeAnyToken() will consume a code-completion
token without invoking code-completion.
rdar://12842503
llvm-svn: 178199
Craig Topper