* Handle some situations where we should never make a decl more visible,
even when merging in an explicit visibility.
* Handle attributes in members of classes that are explicitly specialized.
Thanks Nico for the report and testing, Eric for the initial review, and dgregor
for the awesome test27 :-)
llvm-svn: 151236
block pointer that returns a block literal which captures (by copy)
the lambda closure itself. Some aspects of the block literal are left
unspecified, namely the capture variable (which doesn't actually
exist) and the body (which will be filled in by IRgen because it can't
be written as an AST).
Because we're switching to this model, this patch also eliminates
tracking the copy-initialization expression for the block capture of
the conversion function, since that information is now embedded in the
synthesized block literal. -1 side tables FTW.
llvm-svn: 151131
arguments. There are two aspects to this:
- Make sure that when marking the declarations referenced in a
default argument, we don't try to mark local variables, both because
it's a waste of time and because the semantics are wrong: we're not
in a place where we could capture these variables again even if it
did make sense.
- When a lambda expression occurs in a default argument of a
function template, make sure that the corresponding closure type is
considered dependent, so that it will get properly instantiated. The
second bit is a bit of a hack; to fix it properly, we may have to
rearchitect our handling of default arguments, parsing them only
after creating the function definition. However, I'd like to
separate that work from the lambdas work.
llvm-svn: 151076
stable mangling, since these lambdas can end up in multiple
translation units. Sema is responsible for deciding when this is the
case, because it's already responsible for choosing the mangling
number.
llvm-svn: 151029
default arguments of function parameters. This simple-sounding task is
complicated greatly by two issues:
(1) Default arguments aren't actually a real context, so we need to
maintain extra state within lambda expressions to track when a
lambda was actually in a default argument.
(2) At the time that we parse a default argument, the FunctionDecl
doesn't exist yet, so lambda closure types end up in the enclosing
context. It's not clear that we ever want to change that, so instead
we introduce the notion of the "effective" context of a declaration
for the purposes of name mangling.
llvm-svn: 151011
name mangling in the Itanium C++ ABI for lambda expressions is so
dependent on context, we encode the number used to encode each lambda
as part of the lambda closure type, and maintain this value within
Sema.
Note that there are a several pieces still missing:
- We still get the linkage of lambda expressions wrong
- We aren't properly numbering or mangling lambda expressions that
occur in default function arguments or in data member initializers.
- We aren't (de-)serializing the lambda numbering tables
llvm-svn: 150982
complex numbers. Treat complex numbers as arrays of the corresponding component
type, in order to make std::complex behave properly if implemented in terms of
_Complex T.
Apparently libstdc++'s std::complex is implemented this way, and we were
rejecting a member like this:
constexpr double real() { return __real__ val; }
because it was marked constexpr but unable to produce a constant expression.
llvm-svn: 150895
We now generate temporary arrays to back std::initializer_list objects
initialized with braces. The initializer_list is then made to point at
the array. We support both ptr+size and start+end forms, although
the latter is untested.
Array lifetime is correct for temporary std::initializer_lists (e.g.
call arguments) and local variables. It is untested for new expressions
and member initializers.
Things left to do:
Massively increase the amount of testing. I need to write tests for
start+end init lists, temporary objects created as a side effect of
initializing init list objects, new expressions, member initialization,
creation of temporary objects (e.g. std::vector) for initializer lists,
and probably more.
Get lifetime "right" for member initializers and new expressions. Not
that either are very useful.
Implement list-initialization of array new expressions.
llvm-svn: 150803
conversion to function pointer. Rather than having IRgen synthesize
the body of this function, we instead introduce a static member
function "__invoke" with the same signature as the lambda's
operator() in the AST. Sema then generates a body for the conversion
to function pointer which simply returns the address of __invoke. This
approach makes it easier to evaluate a call to the conversion function
as a constant, makes the linkage of the __invoke function follow the
normal rules for member functions, and may make life easier down the
road if we ever want to constexpr'ify some of lambdas.
Note that IR generation is responsible for filling in the body of
__invoke (Sema just adds a dummy body), because the body can't
generally be expressed in C++.
Eli, please review!
llvm-svn: 150783
Holding the constructor directly makes no sense when list-initialized arrays come into play. The constructor is now held in a CXXConstructExpr, if construction is what is done. The new design can also distinguish properly between list-initialization and direct-initialization, as well as implicit default-initialization constructors and explicit value-initialization constructors. Finally, doing it this way removes redundance from the AST because CXXNewExpr doesn't try to handle both the allocation and the initialization responsibilities.
This breaks the static analysis of new expressions. I've filed PR12014 to track this.
llvm-svn: 150682
* Fix bug when determining whether && / || are potential constant expressions
* Try harder when determining whether ?: is a potential constant expression
* Produce a diagnostic on sizeof(VLA) to provide a better source location
llvm-svn: 150657
pointers and block pointers). We use dummy definitions to keep the
invariant that an implicit, used definition has a body; IR generation
will substitute the actual contents, since they can't be represented
as C++.
For the block pointer case, compute the copy-initialization needed to
capture the lambda object in the block, which IR generation will need
later.
llvm-svn: 150645
function, provide a specialized diagnostic that indicates the kind of
special member function (default constructor, copy assignment
operator, etc.) and that it was implicitly deleted. Add a hook where
we can provide more detailed information later.
llvm-svn: 150611
to be core constant expressions (including pointers and references to
temporaries), and makes constexpr calculations Turing-complete. A Turing machine
simulator is included as a testcase.
This opens up the possibilty of removing CCValue entirely, and removing some
copies from the constant evaluator in the process, but that cleanup is not part
of this change.
llvm-svn: 150557
is general goodness because representations of member pointers are
not always equivalent across member pointer types on all ABIs
(even though this isn't really standard-endorsed).
Take advantage of the new information to teach IR-generation how
to do these reinterprets in constant initializers. Make sure this
works when intermingled with hierarchy conversions (although
this is not part of our motivating use case). Doing this in the
constant-evaluator would probably have been better, but that would
require a *lot* of extra structure in the representation of
constant member pointers: you'd really have to track an arbitrary
chain of hierarchy conversions and reinterpretations in order to
get this right. Ultimately, this seems less complex. I also
wasn't quite sure how to extend the constant evaluator to handle
foldings that we don't actually want to treat as extended
constant expressions.
llvm-svn: 150551
constructor, and that constructor is used to initialize an object of static
storage duration such that all members and bases are initialized by constant
expressions, constant initialization is performed. In this case, the object
can still have a non-trivial destructor, and if it does, we must emit a dynamic
initializer which performs no initialization and instead simply registers that
destructor.
llvm-svn: 150419
expressions. This is mostly a simple refact, splitting the main "start
a lambda expression" function into smaller chunks that are driven
either from the parser (Sema::ActOnLambdaExpr) or during AST
transformation (TreeTransform::TransformLambdaExpr). A few minor
interesting points:
- Added new entry points for TreeTransform, so that we can
explicitly establish the link between the lambda closure type in the
template and the lambda closure type in the instantiation.
- Added a bit into LambdaExpr specifying whether it had an explicit
result type or not. We should have had this anyway.
This code is 'lightly' tested.
llvm-svn: 150417
CXXRecordDecl in a way that actually makes some sense:
- LambdaExpr contains all of the information for initializing the
lambda object, including the capture initializers and associated
array index variables.
- CXXRecordDecl's LambdaDefinitionData contains the captures, which
are needed to understand the captured variable references in the
body of the lambda.
llvm-svn: 150401
LambdaExpr over to the CXXRecordDecl. This allows us to eliminate the
back-link from the closure type to the LambdaExpr, which will simplify
and lazify AST deserialization.
llvm-svn: 150393
1358, 1360, 1452 and 1453.
- Instantiations of constexpr functions are always constexpr. This removes the
need for separate declaration/definition checking, which is now gone.
- This makes it possible for a constexpr function to be virtual, if they are
only dependently virtual. Virtual calls to such functions are not constant
expressions.
- Likewise, it's now possible for a literal type to have virtual base classes.
A constexpr constructor for such a type cannot actually produce a constant
expression, though, so add a special-case diagnostic for a constructor call
to such a type rather than trying to evaluate it.
- Classes with trivial default constructors (for which value initialization can
produce a fully-initialized value) are considered literal types.
- Classes with volatile members are not literal types.
- constexpr constructors can be members of non-literal types. We do not yet use
static initialization for global objects constructed in this way.
llvm-svn: 150359
id-expression 'x' will compute the type based on the assumption that
'x' will be captured, even if it isn't captured, per C++11
[expr.prim.lambda]p18. There are two related refactors that go into
implementing this:
1) Split out the check that determines whether we should capture a
particular variable reference, along with the computation of the
type of the field, from the actual act of capturing the
variable.
2) Always compute the result of decltype() within Sema, rather than
AST, because the decltype() computation is now context-sensitive.
llvm-svn: 150347
instead of having a special-purpose function.
- ActOnCXXDirectInitializer, which was mostly duplication of
AddInitializerToDecl (leading e.g. to PR10620, which Eli fixed a few days
ago), is dropped completely.
- MultiInitializer, which was an ugly hack I added, is dropped again.
- We now have the infrastructure in place to distinguish between
int x = {1};
int x({1});
int x{1};
-- VarDecl now has getInitStyle(), which indicates which of the above was used.
-- CXXConstructExpr now has a flag to indicate that it represents list-
initialization, although this is not yet used.
- InstantiateInitializer was renamed to SubstInitializer and simplified.
- ActOnParenOrParenListExpr has been replaced by ActOnParenListExpr, which
always produces a ParenListExpr. Placed that so far failed to convert that
back to a ParenExpr containing comma operators have been fixed. I'm pretty
sure I could have made a crashing test case before this.
The end result is a (I hope) considerably cleaner design of initializers.
More importantly, the fact that I can now distinguish between the various
initialization kinds means that I can get the tricky generalized initializer
test cases Johannes Schaub supplied to work. (This is not yet done.)
This commit passed self-host, with the resulting compiler passing the tests. I
hope it doesn't break more complicated code. It's a pretty big change, but one
that I feel is necessary.
llvm-svn: 150318
to pretty-print such function types better, and to fix a case where we were not
instantiating templates in lexical order. In passing, move the Variadic bit from
Type's bitfields to FunctionProtoType to get the Type bitfields down to 32 bits.
Also ensure that we always substitute the return type of a function when
substituting explicitly-specified arguments, since that can cause us to bail
out with a SFINAE error before we hit a hard error in parameter substitution.
llvm-svn: 150241
Benjamin Kramer