block pointers) that don't have any qualification to be POD types. We
were previously considering them to be non-POD types, because this was
convenient in C++ for is_pod-like traits. However, we now end up
inferring lifetime in such cases (template arguments infer __strong),
so it is not necessary.
Moreover, we want rvalues of object type (which have their lifetime
stripped) to be PODs to allow, e.g., va_arg(arglist, id) to function
properly. Fixes <rdar://problem/9758798>.
llvm-svn: 134993
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
-Remove unnecessary 'return'.
-Remove unnecessary 'if' check (llvm_unreachable make sure attrStr will be non-null)
-Add a test of transferring ownership to a reference cast type.
llvm-svn: 134285
cast type has no ownership specified, implicitly "transfer" the ownership of the cast'ed type
to the cast type:
id x;
(NSString**)&x; // Casting as (__strong NSString**).
llvm-svn: 134275
cast type has no ownership specified, implicitly "transfer" the ownership of the cast'ed type
to the cast type:
id x;
static_cast<NSString**>(&x); // Casting as (__strong NSString**).
This currently only works for C++ named casts, C casts to follow.
llvm-svn: 134273
silently dropped ownership qualifiers that were being applied to
ownership-qualified, substituted type that was *not* a substituted
template type parameter. We now provide a diagnostic in such cases,
and recover by dropping the added qualifiers.
Document this behavior in the ARC specification.
llvm-svn: 133309
ownership-unqualified retainable object type as __strong. This allows
us to write, e.g.,
std::vector<id>
and we'll infer that the vector's element types have __strong
ownership semantics, which is far nicer than requiring:
std::vector<__strong id>
Note that we allow one to override the ownership qualifier of a
substituted template type parameter, e.g., given
template<typename T>
struct X {
typedef __weak T type;
};
X<id> is treated the same as X<__strong id>. At instantiation type,
the __weak in "__weak T" overrides the (inferred or specified)
__strong on the template argument type, so that we can still provide
metaprogramming transformations.
This is part of <rdar://problem/9595486>.
llvm-svn: 133303
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
Related result types apply Cocoa conventions to the type of message
sends and property accesses to Objective-C methods that are known to
always return objects whose type is the same as the type of the
receiving class (or a subclass thereof), such as +alloc and
-init. This tightens up static type safety for Objective-C, so that we
now diagnose mistakes like this:
t.m:4:10: warning: incompatible pointer types initializing 'NSSet *'
with an
expression of type 'NSArray *' [-Wincompatible-pointer-types]
NSSet *array = [[NSArray alloc] init];
^ ~~~~~~~~~~~~~~~~~~~~~~
/System/Library/Frameworks/Foundation.framework/Headers/NSObject.h:72:1:
note:
instance method 'init' is assumed to return an instance of its
receiver
type ('NSArray *')
- (id)init;
^
It also means that we get decent type inference when writing code in
Objective-C++0x:
auto array = [[NSMutableArray alloc] initWithObjects:@"one", @"two",nil];
// ^ now infers NSMutableArray* rather than id
llvm-svn: 132868
return <expression> ;
in blocks with a 'void' result type, so long as <expression> has type
'void'. This follows the rules for C++ functions.
llvm-svn: 132658
bit by allowing __weak and __strong to be added/dropped as part of
implicit conversions (qualification conversions in C++). A little
history: GCC lets one add/remove/change GC qualifiers just about
anywhere, implicitly. Clang did roughly the same before, but we
recently normalized the semantics of qualifiers across the board to
get a semantics that we could reason about (yay). Unfortunately, this
tightened the screws a bit too much for GC qualifiers, where it's
common to add/remove these qualifiers at will.
Overall, we're still in better shape than we were before: we don't
permit directly changing the GC qualifier (e.g., __weak -> __strong),
so type safety is improved. More importantly, we're internally
consistent in our handling of qualifiers, and the logic that allows
adding/removing GC qualifiers (but not adding/removing address
spaces!) only touches two obvious places.
Fixes <rdar://problem/9402499>.
llvm-svn: 131065
any names that aren't in the appropriate identifier namespaces. Fixes
an embarrassing bug where we give a redefinition error due to an
Objective-C category (<rdar://problem/9388207>).
llvm-svn: 131036
determine which is a better conversion to "void*", be sure to perform
the comparison using the safe-for-id
ASTContext::canAssignObjCInterfaces() rather than the asserts-with-id
ASTContext::canAssignObjCInterfaces().
Fixes <rdar://problem/9327203>.
llvm-svn: 130259
the qualifiers (e.g., GC qualifiers) on the type we're converting
from, rather than just blindly adopting the qualifiers of the type
we're converting to or dropping qualifiers altogether.
As an added bonus, properly diagnose GC qualifier mismatches to
eliminate a crash in the overload resolution failure diagnostics.
llvm-svn: 130255
Objective-C pointer to void* as a "conversion to void*". This allows
us to prefer an Objective-C object pointer conversion to a superclass
object pointer over an Objective-C object pointer conversion to
cv-void*. Fixes PR9735.
llvm-svn: 129603
ActOnFinishFunctionBody/ActOnBlockStmtExpr. This way, we ensure that
we diagnose undefined labels before the jump-scope checker gets run,
since the jump-scope checker requires (as its invariant) that all of
the GotoStmts be wired up correctly.
Fixes PR9495.
llvm-svn: 127738
a glvalue as a temporary. Previously, we were enumerating all of the
cases that coul return glvalues and might be called with
Sema::MaybeBindToTemporary(), but that was gross and we missed the
Objective-C property reference case.
llvm-svn: 125070
Fariborz Jahanian