when returning an NRVO candidate expression. For example, this
properly picks the move constructor when dealing with code such as
MoveOnlyType f() { MoveOnlyType mot; return mot; }
The previously-XFAIL'd rvalue-references test case now works, and has
been moved into the appropriate paragraph-specific test case.
llvm-svn: 123992
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
specification. In particular, an rvalue reference can bind to an
initializer expression that is an lvalue if the referent type and the
initializer expression type are not reference-related. This is a newer
formulation to the previous "rvalue references can never bind to
lvalues" rule.
llvm-svn: 123952
working paper's structure. The only functional change here is that we
now handling binding to array rvalues, which we would previously reject.
llvm-svn: 123918
involving rvalue references, to start scoping out what is and what
isn't implemented. In the process, tweak some standards citations,
type desugaring, and teach the tentative parser about && in
ptr-operator.
llvm-svn: 123913
together. In particular:
- Handle the use of captured parameter pack names within blocks
(BlockDeclRefExpr understands parameter packs now)
- Handle the declaration and expansion of parameter packs within a block's
parameter list, e.g., ^(Args ...args) { ... })
- Handle instantiation of blocks where the return type was not
explicitly specified. (unrelated, but necessary for my tests).
Together, these fixes should make blocks and variadic templates work
reasonably well together. Note that BlockDeclRefExpr is still broken
w.r.t. its computation of type and value dependence, which will still
cause problems for blocks in templates.
llvm-svn: 123849
a pack expansion, e.g., the parameter pack Values in:
template<typename ...Types>
struct Outer {
template<Types ...Values>
struct Inner;
};
This new implementation approach introduces the notion of an
"expanded" non-type template parameter pack, for which we have already
expanded the types of the parameter pack (to, say, "int*, float*",
for Outer<int*, float*>) but have not yet expanded the values. Aside
from creating these expanded non-type template parameter packs, this
patch updates template argument checking and non-type template
parameter pack instantiation to make use of the appropriate types in
the parameter pack.
llvm-svn: 123845
non-variadic function template over a variadic one. This matches GCC
and the intent of the C++0x wording, in a way that I think is likely
to be acceptable to the committee.
llvm-svn: 123581
template template parameter pack that cannot be fully expanded because
its enclosing pack expansion could not be expanded. This form of
TemplateName plays the same role as SubstTemplateTypeParmPackType and
SubstNonTypeTemplateParmPackExpr do for template type parameter packs
and non-type template parameter packs, respectively.
We should now handle these multi-level pack expansion substitutions
anywhere. The largest remaining gap in our variadic-templates support
is that we cannot cope with non-type template parameter packs whose
type is a pack expansion.
llvm-svn: 123521
that captures the substitution of a non-type template argument pack
for a non-type template parameter pack within a pack expansion that
cannot be fully expanded. This follows the approach taken by
SubstTemplateTypeParmPackType.
llvm-svn: 123506
expansion in it, we may end up instantiating to an empty
expression-list. In this case, the variable is uninitialized; tweak
the instantiation logic to handle this case. Fixes PR8977.
llvm-svn: 123449
expansion, when it is known due to the substitution of an out
parameter pack. This allows us to properly handle substitution into
pack expansions that involve multiple parameter packs at different
template parameter levels, even when this substitution happens one
level at a time (as with partial specializations of member class
templates and the signatures of member function templates).
Note that the diagnostic we provide when there is an arity mismatch
between an outer parameter pack and an inner parameter pack in this
case isn't as clear as the normal diagnostic for an arity
mismatch. However, this doesn't matter because these cases are very,
very rare and (even then) only typically occur in a SFINAE context.
The other kinds of pack expansions (expression, template, etc.) still
need to support optional tracking of the number of expansions, and we
need the moral equivalent of SubstTemplateTypeParmPackType for
substituted argument packs of template template and non-type template
parameters.
llvm-svn: 123448
involve template parameter packs at multiple template levels that
occur within the signatures members of class templates (and partial
specializations thereof). This is a work-in-progress that is deficient
in several ways, notably:
- It only works for template type parameter packs, but we need to
also support non-type template parameter packs and template template
parameter packs.
- It doesn't keep track of the lengths of the substituted argument
packs in the expansion, so it can't properly diagnose length
mismatches.
However, this is a concrete step in the right direction.
llvm-svn: 123425
when we're actually matching a template template argument to a
template template parameter. Otherwise, use strict matching.
Fixes <rdar://problem/8859985> clang++: variadics and out-of-line definitions.
llvm-svn: 123385
matching of variadic template template parameters to template
arguments. This paragraph was the subject of ISO C++ committee
document N2555: Extending Variadic Template Template Parameters.
llvm-svn: 123348
another pack expansion type. This can happen when rebuilding types in
the current instantiation.
Fixes <rdar://problem/8848837> (Clang crashing on libc++ <functional>).
llvm-svn: 123316
and function templates that contain variadic templates. This involves
three small-ish changes:
(1) When transforming a pack expansion, if the transformed argument
still contains unexpanded parameter packs, build a pack
expansion. This can happen during the substitution that occurs into
class template partial specialiation template arguments during
partial ordering.
(2) When performing template argument deduction where the argument
is a pack expansion, match against the pattern of that pack
expansion.
(3) When performing template argument deduction against a non-pack
parameter, or a non-expansion template argument, deduction fails if
the argument itself is a pack expansion (C++0x
[temp.deduct.type]p22).
llvm-svn: 123279
number of explicit call arguments. This actually fixes an erroneous
test for [temp.deduct.partial]p11, where we were considering
parameters corresponding to arguments beyond those that were
explicitly provided.
llvm-svn: 123244
parameters it expanded to, map exactly the number of function
parameters that were expanded rather than just running to the end of
the instantiated parameter list. This finishes the implementation of
the last sentence of C++0x [temp.deduct.call]p1.
llvm-svn: 123213
sentence of [temp.deduct.call]p1, both of which concern the
non-deducibility of parameter packs not at the end of a
parameter-type-list. The latter isn't fully implemented yet; see the
new FIXME.
llvm-svn: 123210
expression kinds. This is (indirectly) a test verifying that the
recursive AST visitor is visiting the children of these expression
nodes.
llvm-svn: 123198
pack expansions in template argument lists and function parameter
lists. The implementation of this paragraph should be complete
*except* for cases where we're substituting into one of the unexpanded
packs in a pack expansion; that's a general issue I haven't solved yet.
llvm-svn: 123188
allows an argument pack determines via explicit specification of
function template arguments to be extended by further, deduced
arguments. For example:
template<class ... Types> void f(Types ... values);
void g() {
f<int*, float*>(0, 0, 0); // Types is deduced to the sequence int*, float*, int
}
There are a number of FIXMEs in here that indicate places where we
need to implement + test retained expansions, plus a number of other
places in deduction where we need to correctly cope with the
explicitly-specified arguments when deducing an argument
pack. Furthermore, it appears that the RecursiveASTVisitor needs to be
auditied; it's missing some traversals (especially w.r.t. template
arguments) that cause it not to find unexpanded parameter packs when
it should.
The good news, however, is that the tr1::tuple implementation now
works fully, and the tr1::bind example (both from N2080) is actually
working now.
llvm-svn: 123163
tuple class template. This implementation is boosted directly from the
variadic templates proposal. N2080.
Note that one section is #ifdef'd out. I'll implement that aspect of
template argument deduction next.
llvm-svn: 123016
parameters into parameter types, so that substitution of
explicitly-specified function template arguments uses the same
path. This enables the use of explicitly-specified function template
arguments with variadic templates.
llvm-svn: 122986
template whose last parameter is a parameter pack. This allows us to
form a call to, e.g.,
template<typename ...Args1, typename ...Args2>
void f(std::pair<Args1, Args2> ...pairs);
given zero or more instances of "pair".
llvm-svn: 122973
1) Declaration of function parameter packs
2) Instantiation of function parameter packs within function types.
3) Template argument deduction of function parameter packs when
matching two function types.
We're missing all of the important template-instantiation logic for
function template definitions, along with template argument deduction
from the argument list of a function call, so don't even think of
trying to use these for real yet.
llvm-svn: 122926
expansions with something that is easier to use correctly: a new
template argment kind, rather than a bit on an existing kind. Update
all of the switch statements that deal with template arguments, fixing
a few latent bugs in the process. I"m happy with this representation,
now.
And, oh look! Template instantiation and deduction work for template
template argument pack expansions.
llvm-svn: 122896
for template template argument pack expansions. This allows fun such
as:
template<template<class> class ...> struct apply_impl { /*...*/ };
template<template<class> class ...Metafunctions> struct apply {
typedef typename apply_impl<Metafunctions...>::type type;
};
However, neither template argument deduction nor template
instantiation is implemented for template template argument packs, so
this functionality isn't useful yet.
I'll probably replace the encoding of template template
argument pack expansions in TemplateArgument so that it's harder to
accidentally forget about the expansion. However, this is a step in
the right general direction.
llvm-svn: 122890
specializations. We weren't dealing with any of the cases where the
type of the non-type template argument differs from the type of the
corresponding template parameter in the primary template. We would
think that the template parameter in the partial specialization was
not deducible (and warn about it, incorrectly), then fail to convert a
deduced parameter to the type of the template parameter in the partial
specialization (which may involve truncation, among other
things). Fixes PR8905.
llvm-svn: 122851
declaration name of the array when present. This ensures that
a poor-man's C++03 static_assert will include the user error message
often embedded in the name.
Update all the tests to reflect the new wording, and add a test for the
name behavior.
llvm-svn: 122802
template argument (described by an expression, of course). For
example:
template<int...> struct int_tuple { };
template<int ...Values>
struct square {
typedef int_tuple<(Values*Values)...> type;
};
It also lays the foundation for pack expansions in an initializer-list.
llvm-svn: 122751
caused an assertion when dealing with non-type template parameter
packs. Add some tests for deduction and instantiation of non-type
template parameter packs.
llvm-svn: 122534
extract the appropriate argument from the argument pack (based on the
current substitution index, of course). Simple instantiation of pack
expansions involving non-type template parameter packs now works.
llvm-svn: 122532
packs, e.g.,
template<typename T, unsigned ...Dims> struct multi_array;
along with semantic analysis support for finding unexpanded non-type
template parameter packs in types, expressions, and so on.
Template instantiation involving non-type template parameter packs
probably doesn't work yet. That'll come soon.
llvm-svn: 122527
parameter packs (C++0x [dcl.fct]p13), including disambiguation between
unnamed function parameter packs and varargs (C++0x [dcl.fct]p14) for
cases like
void f(T...)
where T may or may not contain unexpanded parameter packs.
llvm-svn: 122520
specialization's template arguments against the primary template's
template arguments using the obvious, correct method of checking the
injected-class-name type (C++ [temp.class.spec]p9b3). The previous
incarnation of this comparison attempted to use its own formulation of
the injected-class-name, which is redudant and, with the introduction
of variadic templates, became wrong (again).
llvm-svn: 122508
template argument corresponding to a template parameter pack is an
argument pack of a pack expansion of that template parameter
pack. Implements C++0x [temp.dep.type]p2 (at least, as much of it as
we can).
llvm-svn: 122498
parameter packs. In particular, a parameter pack not otherwise deduced
is deduced to an empty parameter pack.
The C++0x wording here is a bit unfortunate; this should really only
apply to function templates, and it mentions "trailing" parameter
packs, which doesn't really make sense in the context of function
templates. Will file a core issue separately.
llvm-svn: 122463
the presence of a pack expansion anywhere except at the end of a
template-argument-list causes the entire template-argument-list to be
a non-deduced context.
llvm-svn: 122461
single routine. Extend that routine to handle consistency
checking for template argument packs, so that we can compare the
deduced packs for template parameter packs across different pack
expansions.
llvm-svn: 122452
pattern is a template argument, which involves repeatedly deducing
template arguments using the pattern of the pack expansion, then
bundling the resulting deductions into an argument pack.
We can now handle a variety of simple list-handling metaprograms using
variadic templates. See, e.g., the new "count" metaprogram.
llvm-svn: 122439
dependent template specialization type, the number of template
arguments need not match precisely. Rather than checking the number of
arguments eagerly (which does not consider argument packs), let the
deduction routine for template argument lists cope with too many/too
few arguments.
llvm-svn: 122425
deduction. Unify all of the looping over template arguments for
deduction purposes into a single place, where argument pack expansion
occurs; this is also the hook for deducing from pack expansions, which
itself is not yet implemented.
For now, at least we can handle a basic "count" metafunction written
with variadics. See the new test for the formulation that works.
llvm-svn: 122418
Anders Carlsson