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
type rather than just the literal 'false'. This begins fixing PR9612,
but the message is now wrong. WIP, the cleanup of the messaging is next.
llvm-svn: 129204
This patch authored by Eric Niebler.
Many methods on the Sema class (e.g. ConvertPropertyForRValue) take Expr
pointers as in/out parameters (Expr *&). This is especially true for the
routines that apply implicit conversions to nodes in-place. This design is
workable only as long as those conversions cannot fail. If they are allowed
to fail, they need a way to report their failures. The typical way of doing
this in clang is to use an ExprResult, which has an extra bit to signal a
valid/invalid state. Returning ExprResult is de riguour elsewhere in the Sema
interface. We suggest changing the Expr *& parameters in the Sema interface
to ExprResult &. This increases interface consistency and maintainability.
This interface change is important for work supporting MS-style C++
properties. For reasons explained here
<http://lists.cs.uiuc.edu/pipermail/cfe-dev/2011-February/013180.html>,
seemingly trivial operations like rvalue/lvalue conversions that formerly
could not fail now can. (The reason is that given the semantics of the
feature, getter/setter method lookup cannot happen until the point of use, at
which point it may be found that the method does not exist, or it may have the
wrong type, or overload resolution may fail, or it may be inaccessible.)
llvm-svn: 129143
when the resolution took place due to a single template specialization
being named with an explicit template argument list. In this case, the
"resolution" doesn't take into account the target type at all, and
therefore can take place for functions, static member functions, and
*non-static* member functions. The latter weren't being properly checked
and their proper form enforced in this scenario. We now do so.
The result of this last form slipping through was some confusing logic
in IsStandardConversion handling of these resolved address-of
expressions which eventually exploded in an assert. Simplify this logic
a bit and add some more aggressive asserts to catch improperly formed
expressions getting into this routine.
Finally add systematic testing of member functions, both static and
non-static, in the various forms they can take. One of these is
essentially PR9563, and this commit fixes the crash in that PR. However,
the diagnostics for this are still pretty terrible. We at least are now
accepting the correct constructs and rejecting the invalid ones rather
than accepting invalid or crashing as before.
llvm-svn: 128456
which versions of an OS provide a certain facility. For example,
void foo()
__attribute__((availability(macosx,introduced=10.2,deprecated=10.4,obsoleted=10.6)));
says that the function "foo" was introduced in 10.2, deprecated in
10.4, and completely obsoleted in 10.6. This attribute ties in with
the deployment targets (e.g., -mmacosx-version-min=10.1 specifies that
we want to deploy back to Mac OS X 10.1). There are several concrete
behaviors that this attribute enables, as illustrated with the
function foo() above:
- If we choose a deployment target >= Mac OS X 10.4, uses of "foo"
will result in a deprecation warning, as if we had placed
attribute((deprecated)) on it (but with a better diagnostic)
- If we choose a deployment target >= Mac OS X 10.6, uses of "foo"
will result in an "unavailable" warning (in C)/error (in C++), as
if we had placed attribute((unavailable)) on it
- If we choose a deployment target prior to 10.2, foo() is
weak-imported (if it is a kind of entity that can be weak
imported), as if we had placed the weak_import attribute on it.
Naturally, there can be multiple availability attributes on a
declaration, for different platforms; only the current platform
matters when checking availability attributes.
The only platforms this attribute currently works for are "ios" and
"macosx", since we already have -mxxxx-version-min flags for them and we
have experience there with macro tricks translating down to the
deprecated/unavailable/weak_import attributes. The end goal is to open
this up to other platforms, and even extension to other "platforms"
that are really libraries (say, through a #pragma clang
define_system), but that hasn't yet been designed and we may want to
shake out more issues with this narrower problem first.
Addresses <rdar://problem/6690412>.
As a drive-by bug-fix, if an entity is both deprecated and
unavailable, we only emit the "unavailable" diagnostic.
llvm-svn: 128127
overload, so that we actually do the resolution for full expressions
and emit more consistent, useful diagnostics. Also fixes an IRGen
crasher, where Sema wouldn't diagnose a resolvable bound member
function template-id used in a full-expression (<rdar://problem/9108698>).
llvm-svn: 127747
parameter, save the instantiated default template arguments along with
the explicitly-specified template argument list. That way, we prefer
the default template template arguments corresponding to the template
template parameter rather than those of its template template argument.
This addresses the likely direction of C++ core issue 150, and fixes
PR9353/<rdar://problem/9069136>, bringing us closer to the behavior of
EDG and GCC.
llvm-svn: 126920
possible for these to show up due to metaprogramming both in unevaluated
contexts and compile-time dead branches.
Those aren't the bugs we're looking for.
llvm-svn: 126739
UnresolvedLookupExpr and UnresolvedMemberExpr.
Also, improve the computation that checks whether the base of a member
expression (either unresolved or dependent-scoped) is implicit. The
previous check didn't cover all of the cases we use in our
representation, which threw off source-location information for these
expressions (which, in turn, caused some breakage in libclang's token
annotation).
llvm-svn: 126681
marking selected overloads into the callers. This allows a few callers
to skip it altogether (they would have anyways because they weren't
interested in successful overloads) or defer until after further checks
take place much like the check required for PR9323 to avoid marking
unused copy constructors.
llvm-svn: 126503
declarations as referenced when in fact we're not going to even form
a call in the AST. This is significant because we attempt to allow as an
extension classes with intentionally private and undefined copy
constructors to have temporaries bound to references, and so shouldn't
warn about the lack of definition for that copy constructor when the
class is internal.
Doug, John wasn't really satisfied with the presence of overloading at
all. This is a stop-gap and there may be a better solution. If you can
give me some hints for how you'd prefer to see this solved, I'll happily
switch things over.
llvm-svn: 126480
nested-name-specifiers throughout the parser, and provide a new class
(NestedNameSpecifierLoc) that contains a nested-name-specifier along
with its type-source information.
Right now, this information is completely useless, because we don't
actually store the source-location information anywhere in the
AST. Call this Step 1/N.
llvm-svn: 126391
includes explicitly-specified template arguments) to a function
template specialization in cases where no deduction is performed or
deduction fails. Patch by Faisal Vali, fixes PR7505!
llvm-svn: 126048
conversions (<rdar://problem/8592139>) for overload resolution. The
conversion ranking mirrors C++'s conversion ranking fairly closely,
except that we use a same pseudo-subtyping relationship employed by
Objective-C pointer assignment rather than simple checking
derived-to-base conversions. This change covers:
- Conversions to pointers to a specific object type are better than
conversions to 'id', 'Class', qualified 'id', or qualified 'Class'
(note: GCC doesn't perform this ranking, but it matches C++'s rules
for ranking conversions to void*).
- Conversions to qualified 'id' or qualified 'Class' are better than
conversions to 'id' or 'Class', respectively.
- When two conversion sequences convert to the same type, rank the
conversions based on the relationship between the types we're
converting from.
- When two conversion sequences convert from the same non-id,
non-Class type, rank the conversions based on the relationship of
the types we're converting to. (note: GCC allows this ranking even
when converting from 'id', which is extremeley dangerous).
llvm-svn: 124591
derived-to-base cast that also casts away constness (one of the cases
for static_cast followed by const_cast) would be treated as a bit-cast
rather than a derived-to-base class, causing miscompiles and
heartburn.
Fixes <rdar://problem/8913298>.
llvm-svn: 124340
overload a function without a ref-qualifier (C++0x
[over.load]p2). This, apparently, completes the implementation of
rvalue references for *this.
llvm-svn: 124321
reference binding is for the implicit object parameter of a member
function with a ref-qualifier. My previous comment, that we didn't
need to track this explicitly, was wrong: we do in fact get
rvalue-references-prefer-rvalues overloading with ref-qualifiers.
llvm-svn: 124313
the presence and form of a ref-qualifier. Note that we do *not* yet
implement the restriction in C++0x [over.load]p2 that requires either
all non-static functions with a given parameter-type-list to have a
ref-qualifier or none of them to have a ref-qualifier.
llvm-svn: 124297
for reference binding (C++ [over.rank.ics]p3b1sb4), so that we prefer
the binding of an lvalue reference to a function lvalue over the
binding of an rvalue reference. This change resolves the ambiguity
with std::forward and lvalue references to function types in a way
that seems consistent with the original rvalue references proposal.
My proposed wording for this change is shown in
isBetterReferenceBindingKind(); we'll try to get this change adopted
in the C++0x working paper as well.
llvm-svn: 124236
(C++0x [over.ics.rank]p3) when one binding is an lvalue reference and
the other is an rvalue reference that binds to an rvalue. In
particular, we were using the predict "is an rvalue reference" rather
than "is an rvalue reference that binds to an rvalue", which was
incorrect in the one case where an rvalue reference can bind to an
lvalue: function references.
This particular issue cropped up with std::forward, where Clang was
picking an std::forward overload while forwarding an (lvalue)
reference to a function. However (and unfortunately!), the right
answer for this code is that the call to std::forward is
ambiguous. Clang now gets that right, but we need to revisit the
std::forward implementation in libc++.
llvm-svn: 124216
implementation used by overload resolution to support rvalue
references. The original commits caused PR9026 and some
hard-to-reproduce self-host breakage.
The only (crucial!) difference between this commit and the previous
commits is that we now properly check the SuppressUserConversions flag
before attempting to perform a second user-defined conversion in
reference binding, breaking the infinite recursion chain of
user-defined conversions.
Rvalue references should be working a bit better now.
llvm-svn: 124121
resolution to match the latest C++0x working paper's semantics. The
implementation now matching up with the reference-binding
implementation used for initialization.
llvm-svn: 123977
call (C++0x [temp.deduct.call]p3).
As part of this, start improving the reference-binding implementation
used in the computation of implicit conversion sequences (for overload
resolution) to reflect C++0x semantics. It still needs more work and
testing, of course.
llvm-svn: 123966
Douglas Gregor