where we have an immediate need of a retained value.
As an exception, don't do this when the call is made as the immediate
operand of a __bridge retain. This is more in the way of a workaround
than an actual guarantee, so it's acceptable to be brittle here.
rdar://problem/9504800
llvm-svn: 134605
throw-expressions, such that we don't consider the NRVO when the
non-volatile automatic object comes from outside the innermost try
scope (C++0x [class.copymove]p13). In C++98/03, our ASTs were
incorrect but it didn't matter because IR generation doesn't actually
apply the NRVO here. In C++0x, however, we were moving from an object
when in fact we should have copied from it. Fixes PR10142 /
<rdar://problem/9714312>.
llvm-svn: 134548
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
Allow to include or exclude code depending on if a symbol exists or not. Just like a #ifdef but for C/C++ symbols.
More doc: http://msdn.microsoft.com/en-us/library/x7wy9xh3(v=VS.100).aspx
Support at class and namespace scopes will be added later.
llvm-svn: 131014
instead of 'int'.
The Embarcadero spec says 'unsigned int', not 'int'. That's what
'size_t' is on Windows, but for Clang using a 'size_t' that can be
larger than int seems more appropriate.
llvm-svn: 130653
functions already precluded dependent types from reaching them.
Also change one of the callers to not error when a trait is applied to
a dependent type. This is a perfectly reasonable pattern, and both Unary
and Binary type traits already support dependent types (by populating
the AST with a nonce value).
Remove the actual diagnostic, since these aren't errors.
llvm-svn: 130651
a switch with any default case. This both warns when an enumerator is
missing and asserts if a value sneaks through despite the warning.
While in there fix a bunch of coding style issues with this code.
llvm-svn: 130648
As might be surmised from their names, these aren't type traits, they're
expression traits. Amazingly enough, they're expression traits that we
have, and fully implement. These "type" traits are even parsed from the
same tokens as the expression traits. Luckily, the parser only tried the
expression trait parsing for these tokens, so this was all just a pile
of dead code.
llvm-svn: 130643
1) Moved the completeness checking routine above the evaluation routine
so the reader sees that we do in fact check for complete types when
necessary.
2) Remove the FIXME comment about not doing this.
3) Make the arguments to the evaluate function agree in order with those
to the completeness checking function.
4) Completely specify the enumerators for the completeness checking
function rather than relying on a default.
5) Remove a check for the Borland language to only require complete
types in a few places. Borland's own documentation doesn't agree with
this: some of the previously unspecified traits *do* require
a complete type, some don't.
6) Correctly split the traits which do not require complete types from
those that do, clarifying comments and citations to the standard or
other documentation where relevant.
llvm-svn: 130641
trait arguments. Reflow the logic to use early exit instead of a complex
condition expression. Switch to a switch for acting on different type
traits and add a bunch of the recently implemented type traits here.
This fixes one of the regressions with the new __is_standard_layout
trait to again require a complete type. It also fixes some latent bugs
in other traits that never did impose this despite the standard
requiring it. However, all these bugs were hidden for non-borland
systems where the default is to require a complete type.
It's unclear to me what the best approach here is: providing an explicit
lists for the ones requiring complete types only w/ Borland and using
a default for the rest, or forcing this switch to enumerate the traits
and make it clear which way each one goes.
I'm still working on cleaning up the tests so that they actually catch
this, a much more comprehensive update to the tests will come once I've
worked through the bugs I'm finding via inspection.
llvm-svn: 130604
a Type method isStandardLayoutType, to keep our user API matching the
type trait builtins as closely as possible. Also, implement it in terms
of other Type APIs rather than in terms of other type traits. This
models the implementation on that of isLiteralType and isTrivialType.
There remain some common problems with these traits still, so this is
a bit of a WIP. However, we can now fix all of these traits at the same
time and in a consistent manner.
llvm-svn: 130602
type trait. The previous implementation suffered from several problems:
1) It implemented all of the logic in RecordType by walking over every
base and field in a CXXRecordDecl and validating the constraints of
the standard. This made for very straightforward code, but is
extremely inefficient. It also is conceptually wrong, the logic tied
to the C++ definition of standard-layout classes should be in
CXXRecordDecl, not RecordType.
2) To address the performance problems with #1, a cache bit was added to
CXXRecordDecl, and at the completion of every C++ class, the
RecordType was queried to determine if it was a standard layout
class, and that state was cached. Two things went very very wrong
with this. First, the caching version of the query *was never
called*. Even within the recursive steps of the walk over all fields
and bases the caching variant was not called, making each query
a full *recursive* walk. Second, despite the cache not being used, it
was computed for every class declared, even when the trait was never
used in the program. This probably significantly regressed compile
time performance for edge-case files.
3) An ASTContext was required merely to query the type trait because
querying it performed the actual computations.
4) The caching bit wasn't managed correctly (uninitialized).
The new implementation follows the system for all the other traits on
C++ classes by encoding all the state needed in the definition data and
building up the trait incrementally as each base and member are added to
the definition of the class.
The idiosyncracies of the specification of standard-layout classes
requires more state than I would like; currently 5 bits. I could
eliminate one of the bits easily at the expense of both clarity and
resilience of the code. I might be able to eliminate one of the other
bits by computing its state in terms of other state bits in the
definition. I've already done that in one place where there was a fairly
simple way to achieve it.
It's possible some of the bits could be moved out of the definition data
and into some other structure which isn't serialized if the serialized
bloat is a problem. That would preclude serialization of a partial class
declaration, but that's likely already precluded.
Comments on any of these issues welcome.
llvm-svn: 130601
Patch authored by John Wiegley.
These are array type traits used for parsing code that employs certain
features of the Embarcadero C++ compiler: __array_rank(T) and
__array_extent(T, Dim).
llvm-svn: 130351
Patch authored by John Wiegley.
These type traits are used for parsing code that employs certain features of
the Embarcadero C++ compiler. Several of these constructs are also desired by
libc++, according to its project pages (such as __is_standard_layout).
llvm-svn: 130342
member function, i.e. something of the form 'x.f' where 'f' is a non-static
member function. Diagnose this in the general case. Some of the new diagnostics
are probably worse than the old ones, but we now get this right much more
universally, and there's certainly room for improvement in the diagnostics.
llvm-svn: 130239
Patch authored by David Abrahams.
These two expression traits (__is_lvalue_expr, __is_rvalue_expr) are used for
parsing code that employs certain features of the Embarcadero C++ compiler.
llvm-svn: 130122
This introduces a few APIs on the AST to bundle up the standard-based
logic so that programmatic clients have access to exactly the same
behavior.
There is only one serious FIXME here: checking for non-trivial move
constructors and move assignment operators. Those bits need to be added
to the declaration and accessors provided.
This implementation should be enough for the uses of __is_trivial in
libstdc++ 4.6's C++98 library implementation.
Ideas for more thorough test cases or any edge cases missing would be
appreciated. =D
llvm-svn: 130057
address space. I could see that this functionality would be useful,
but not in its current form (where the address space is ignored):
rather, we'd want to encode the address space into the parameter list
passed to operator new/operator delete somehow, which would require a
bunch more semantic analysis.
llvm-svn: 129593
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
