Commit Graph

434 Commits

Author SHA1 Message Date
Douglas Gregor 8409ccd8f6 C++11 [temp.deduct.call]p6 tweak: when given a set of overlaoded
functions that includes an explicit template argument list, perform
an inner deduction against each of the function templates in that list
and, if successful, use the result of that deduction for the outer
template argument deduction. Fixes PR11713.

llvm-svn: 152575
2012-03-12 21:09:16 +00:00
Douglas Gregor 194ea69d62 When template argument deduction is ignoring qualifiers, perform deep
structural comparison of non-dependent types. Otherwise, we end up
rejecting cases where the non-dependent types don't match due to
qualifiers in, e.g., a pointee type. Fixes PR12132.

llvm-svn: 152529
2012-03-11 03:29:50 +00:00
Eli Friedman 7cd4a9ba48 Improve diagnostics a bit for bad member initializers, and fix an obscure bug involving packs. Fixes PR12049.
llvm-svn: 151130
2012-02-22 04:49:04 +00:00
Sebastian Redl a935179ab7 Represent C++ direct initializers as ParenListExprs before semantic analysis
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- ActOnParenOrParenListExpr has been replaced by ActOnParenListExpr, which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
2012-02-11 23:51:47 +00:00
Douglas Gregor 1f79ca839c When a pack expansion occurs in the template argument list of an alias
template without a corresponding parameter pack, don't immediately
substitute the alias template. This is under discussion in the C++
committee, and may become ill-formed, but for now we match GCC.

llvm-svn: 149697
2012-02-03 17:16:23 +00:00
Douglas Gregor 8e07261362 Implement support for a pack expansion into a fixed-length
template. Such pack expansions can easily fail at template
instantiation time, if the expanded parameter packs are of the wrong
length. Fixes <rdar://problem/10040867>, PR9021, and the example that
came up today at Going Native.

llvm-svn: 149685
2012-02-03 07:34:46 +00:00
Nico Weber a8f80b31f9 Fix "note" of a duplicate explicit instantiation definition following a specialization.
llvm-svn: 147798
2012-01-09 19:52:25 +00:00
Eli Friedman de30e523b4 Tweak the fix to PR8977: an empty expression-list represents value initialization, not default initialization. Fixes PR11712.
llvm-svn: 147620
2012-01-05 22:34:08 +00:00
Richard Smith e434590bd9 Change the diagnostics which said 'accepted as an extension' to instead say
'is an extension'. The former is inappropriate and confusing when building with
-Werror/-pedantic-errors.

llvm-svn: 147357
2011-12-29 21:57:33 +00:00
Nico Weber d3bdadf616 Fix several issues related to specializations and explicit instantiations.
Explicit instantiations following specializations are no-ops and hence have
no PointOfInstantiation. That was done correctly in most cases, but for a
specialization -> instantiation decl -> instantiation definition chain, the
definition didn't realize that it was a no-op. Fix that.

Also, when printing diagnostics for these no-ops, get the diag location from
the decl name location.

Add many test cases, one of them not yet passing (but it failed the same way
before this change). Fixes http://llvm.org/pr11558 and more.

llvm-svn: 147225
2011-12-23 20:58:04 +00:00
Nico Weber 3ffc4c93fd Fix a crash on invalid, http://llvm.org/pr11599
llvm-svn: 146988
2011-12-20 20:32:49 +00:00
Eli Friedman e321795c60 Remove a non-gcc-compatible extension that would apply attributes on declarations without a declarator to structs. Add a warning for ignored attributes. Patch by Michael Han.
llvm-svn: 146796
2011-12-17 00:36:09 +00:00
Richard Smith ad45a8681d Some tests missed from r144056.
llvm-svn: 144060
2011-11-08 02:18:13 +00:00
Douglas Gregor ab6bc1d13e Make the -Wc++11-compat warnings ignored by default, so we don't break
valid C++98/03 code. However, add these warnings to -Wall, for those
who obviously already like clean code.

llvm-svn: 142903
2011-10-25 03:07:45 +00:00
Peter Collingbourne 7d33cd3a2f Fix grammar for C++11 alignment specifiers, and add a few FIXMEs.
llvm-svn: 142760
2011-10-23 20:07:52 +00:00
Peter Collingbourne 9f58d7b789 Diagnose unexpanded parameter packs in member initialisers (including
in-class member initialisers).

llvm-svn: 142758
2011-10-23 18:59:44 +00:00
Richard Smith f411196d15 'extern template' is a C++11 feature. Add an Extension for C++98 (this matches
gcc's behaviour), and a -Wc++98-compat-pedantic warning for C++11.

llvm-svn: 142597
2011-10-20 18:35:58 +00:00
David Blaikie 651c73ce78 Fix pr9789, assert-on-invalid while instantiating an (invalid) class template with a non-final parameter pack. Also improve the warning for non-final parameter packs in this scenario so it only fires once, rather than once for every template parameter after the non-final parameter pack.
llvm-svn: 142473
2011-10-19 05:19:50 +00:00
Richard Smith 465841e48c [temp.explicit]p1: constexpr cannot be specified in explicit instantiations.
llvm-svn: 141982
2011-10-14 19:58:02 +00:00
Richard Smith 9ca5c42582 Update all tests other than Driver/std.cpp to use -std=c++11 rather than
-std=c++0x. Patch by Ahmed Charles!

llvm-svn: 141900
2011-10-13 22:29:44 +00:00
Douglas Gregor ebcfbb5d22 When we determine that a function template specialization produced as
part of template argument deduction is ill-formed, we mark it as
invalid and treat it as a deduction failure. If we happen to find that
specialization again, treat it as a deduction failure rather than
silently building a call to the declaration.

Fixes PR11117, a marvelous bug where deduction failed after creating
an invalid specialization, causing overload resolution to pick a
different candidate. Then we performed a similar overload resolution
later, and happily picked the invalid specialization to
call... resulting in a silent link failure.

llvm-svn: 141809
2011-10-12 20:35:48 +00:00
Douglas Gregor 205d044552 Switch diagnostic text from "C++0x" over to "C++11".
We'd also like for "C++11" or "c++11" to be used for the warning
groups, but without removing the old warning flags. Patches welcome;
I've run out of time to work on this today.

llvm-svn: 141801
2011-10-12 19:26:40 +00:00
John McCall 50a2c2c19d Catch placeholder types in DefaultLvalueConversion
and DefaultFunctionArrayLvalueConversion.  To prevent
significant regression for should-this-be-a-call fixits,
and to repair some such regression from the introduction of
bound member placeholders, make those placeholder checks
try to build calls appropriately.  Harden the build-a-call
logic while we're at it.

llvm-svn: 141738
2011-10-11 23:14:30 +00:00
Douglas Gregor ab96bcf6ea When substituting into a sizeof parameter pack expression in a context
where we can't expand (i.e., multi-level substitution), be sure to
substitute the pack with its level-reduced pack. Fixes PR10230.

llvm-svn: 141568
2011-10-10 18:59:29 +00:00
Douglas Gregor 0c83c8128b Per the note in C++0x [temp.deduct.call]p4, don't attempt template
argument deduction against a function parameter that has no deducible
template parameters in it. Fixes PR8598.

llvm-svn: 141517
2011-10-09 22:06:46 +00:00
Douglas Gregor e9d075e434 A friend template specialization is also dependent if any of its
template arguments are dependent. Fixes PR10913.

llvm-svn: 141515
2011-10-09 20:59:17 +00:00
Sebastian Redl 22653bac1a Declare and define implicit move constructor and assignment operator.
This makes the code duplication of implicit special member handling even worse,
but the cleanup will have to come later. For now, this works.
Follow-up with tests for explicit defaulting and enabling the __has_feature
flag to come.

llvm-svn: 138821
2011-08-30 19:58:05 +00:00
Richard Smith 7b8c3c91f4 PR10359: Template declarations which define classes are not permitted to also contain declarators. Previously we would accept code like this:
template<typename T> struct S { } f() { return 0; }

This case now produces a missing ';' diagnostic, since that seems like a much more likely error than an attempt to declare a function or variable in addition to the class template.

Treat this 

llvm-svn: 135195
2011-07-14 21:35:26 +00:00
Chandler Carruth c933221826 Factor out (some of) the checking for invalid forms of pointer
arithmetic into a couple of common routines. Use these to make the
messages more consistent in the various contexts, especially in terms of
consistently diagnosing binary operators with invalid types on both the
left- and right-hand side. Also, improve the grammar and wording of the
messages some, handling both two pointers and two (different) types.

The wording of function pointer arithmetic diagnostics still strikes me
as poorly phrased, and I worry this makes them slightly more awkward if
more consistent. I'm hoping to fix that with a follow-on patch and test
case that will also make them more helpful when a typedef or template
type parameter makes the type completely opaque.

Suggestions on better wording are very welcome, thanks to Richard Smith
for some initial help on that front.

llvm-svn: 133906
2011-06-27 08:02:19 +00:00
Chandler Carruth 53e61b05ce Accept no-return stripping conversions for pointer type arguments after
deducing template parameter types. Recently Clang began enforcing the
more strict checking that the argument type and the deduced function
parameter type (after substitution) match, but that only consideres
qualification conversions.

One problem with this patch is that we check noreturn conversions and
qualification conversions independently. If a valid conversion would
require *both*, perhaps interleaved with each other, it will be
rejected. If this actually occurs (I'm not yet sure it does) and is in
fact a problem (I'm not yet sure it is), there is a FIXME to implement
more intelligent conversion checking.

However, this step at least allows Clang to resume accepting valid code
we're seeing in the wild.

llvm-svn: 133327
2011-06-18 01:19:03 +00:00
Douglas Gregor e65aacb9e9 Implement the consistency checking for C++ [temp.deduct.call]p3, which
checks that the deduced argument type for a function call matches the
actual argument type provided. The only place we've found where the
consistency checking should actually cause template argument deduction
failure is due to qualifier differences that don't fall into the realm
of qualification conversions (which are *not* checked when we
initially perform deduction). However, we're performing the full
checking as specified in the standard to ensure that no other cases
exist.

Fixes PR9233 / <rdar://problem/9039590>.

llvm-svn: 133163
2011-06-16 16:50:48 +00:00
Douglas Gregor 8a6d0e091b Downgrade the warning about the use of typedefs for class template
specializations within an explicit instantiation to default to off
(enabled by -pedantic). Nobody else seem to implement C++
[temp.explicit]p3. Fixes PR10093.

llvm-svn: 132704
2011-06-07 02:21:18 +00:00
Douglas Gregor 522d5eb7c3 Diagnose the condition in C++ [temp.expl.spec]p16 that prohibits
specializing a member of an unspecialized template, and recover from
such errors without crashing. Fixes PR10024 / <rdar://problem/9509761>.

llvm-svn: 132677
2011-06-06 15:22:55 +00:00
Douglas Gregor 2f157c9ae2 When checking the instantiation of a default template argument against
the template parameter, perform the checking as a "specified" template
argument rather than a "deduced" template argument; the latter implies
stricter type checking that is not permitted for default template
arguments.

Also, cleanup our handling of substitution of explicit template
arguments for a function template. We were actually performing some
substitution of default arguments at this point!

Fixes PR10069.

llvm-svn: 132529
2011-06-03 02:59:40 +00:00
Douglas Gregor b32e825ae4 Fix an incorrect warning about explicit template specializations for
nested types, from Michael Han!

llvm-svn: 132431
2011-06-01 22:37:07 +00:00
Douglas Gregor 4385d8b0a2 Diagnose unexpanded parameter packs in return statements. This
manifested in a crash with blocks in PR9953, but it was a ticking time
bomb for normal functions, too. Fixes PR9953.

llvm-svn: 131731
2011-05-20 15:32:55 +00:00
Douglas Gregor 9d07dfa439 When checking a set of template parameter lists against a
nested-name-specifier, re-evaluate the nested-name-specifier as if we
were entering that context (which we did!), so that we'll resolve a
template-id to a particular class template partial
specialization. Fixes PR9913.

llvm-svn: 131383
2011-05-15 17:27:27 +00:00
Douglas Gregor 347d626cf7 Implement CWG1170, which makes access-control errors into template
argument deduction failures. Only implemented in C++0x, since this is
a significant change in behavior from C++98/03.

llvm-svn: 131209
2011-05-11 23:45:11 +00:00
Douglas Gregor 373af9bc5d When checking for the necessary 'template<>' headers based on the
nested of an out-of-line declaration, only require a 'template<>'
header for each enclosing class template that hasn't been previously
specialized; previously, we were requiring 'template<>' for enclosing
class templates and members of class templates that hadn't been
previously specialized. Fixes <rdar://problem/9422013>.

llvm-svn: 131207
2011-05-11 23:26:17 +00:00
Douglas Gregor 972fe534ed Reimplement Sema::MatchTemplateParametersToScopeSpecifier() based on
the semantic context referenced by the nested-name-specifier rather
than the syntactic form of the nested-name-specifier. The previous
incarnation was based on my complete misunderstanding of C++
[temp.expl.spec]. The latest C++0x working draft clarifies the
requirements here, and this rewrite is intended to follow that.

Along the way, improve source location information in the
diagnostics. For example, if we report that a specific type needs or
doesn't need a 'template<>' header, we dig out that type in the
nested-name-specifier and highlight its range.

Fixes: PR5907, PR9421, PR8277, PR8708, PR9482, PR9668, PR9877, and
<rdar://problem/9135379>.

llvm-svn: 131138
2011-05-10 18:27:06 +00:00
Richard Smith 14034026d6 Slight tweak to alias template error handling: don't guess that a template-id in an alias declaration was meant to be a specialization. Use a generic, but more accurate, diagnostic.
llvm-svn: 130961
2011-05-05 22:36:10 +00:00
Richard Smith 3f1b5d077b Implement support for C++0x alias templates.
llvm-svn: 130953
2011-05-05 21:57:07 +00:00
Chandler Carruth 7c9856deb3 When parsing a template friend declaration we dropped the template
parameters on the floor in certain cases:
class X {
  template <typename T> friend typename A<T>::Foo;
};

This was parsed as a *non* template friend declaration some how, and
received an ExtWarn. Fixing the parser to actually provide the template
parameters to the freestanding declaration parse triggers the code which
specifically looks for such constructs and hard errors on them.

Along the way, this prevents us from trying to instantiate constructs
like the above inside of a outer template. This is important as loosing
the template parameters means we don't have a well formed declaration
and template instantiation will be unable to rebuild the AST. That fixes
a crash in the GCC test suite.

llvm-svn: 130772
2011-05-03 18:35:10 +00:00
Richard Smith 02e85f3bc5 Add support for C++0x's range-based for loops, as specified by the C++11 draft standard (N3291).
llvm-svn: 129541
2011-04-14 22:09:26 +00:00
John McCall a97f329869 Template static data members can have weak_odr linkage, not just
weak linkage.  Also, fix a problem where global weak variables
with non-trivial initializers were getting guard variables, or at
least were checking for them and then crashing.

llvm-svn: 129342
2011-04-12 01:46:54 +00:00
Douglas Gregor 63fab34469 Detect attempts to provide a specialization of a function within a
dependent scope and produce an error (rather than crashing). Fixes PR8979.

llvm-svn: 127749
2011-03-16 19:27:09 +00:00
Douglas Gregor 89f3cd5c15 Clean up our handling of template-ids that resolve down to a single
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
2011-03-16 19:16:25 +00:00
Daniel Dunbar 334b2136f6 Revert r127206 "Detect attempts to provide a specialization of a function within
a...", it appears to cause us to reject various valid codes.

llvm-svn: 127373
2011-03-09 23:24:34 +00:00
Douglas Gregor 6203d49b0e Detect attempts to provide a specialization of a function within a
dependent scope and produce an error (rather than crashing). Fixes PR8979.

llvm-svn: 127206
2011-03-08 02:04:14 +00:00
Douglas Gregor db44611f2e Support explicit template specialization and instantiation for members
of a C++0x inline namespace within enclosing namespaces, as noted in
C++0x [namespace.def]p8.

Fixes <rdar://problem/9006349>, a libc++ failure where Clang was
rejected an explicit specialization of std::swap (since libc++ puts it
into an inline, versioned namespace std::__1).

llvm-svn: 127162
2011-03-07 16:54:27 +00:00
John McCall 8feeb49662 Semantic checking for exception specifications should be triggered by
whether C++ exceptions are enabled, not exceptions in general.  PR9358.

llvm-svn: 126820
2011-03-02 02:04:40 +00:00
Douglas Gregor c52264e719 When we're substituting into a parameter-type-list nested inside the pattern
of an expansion, and we have a paramameter that is not a parameter
pack, don't suppress substitution of parameter packs within this
context.

llvm-svn: 126819
2011-03-02 02:04:06 +00:00
Anders Carlsson 6774b1f1c1 Add -fcxx-exceptions to all tests that use C++ exceptions.
llvm-svn: 126599
2011-02-28 00:40:07 +00:00
Anders Carlsson 479d6f51e3 Pass -fexceptions to all tests that use try/catch/throw.
llvm-svn: 126037
2011-02-19 19:23:03 +00:00
Douglas Gregor b0f2ea9e9e When printing a qualified type, look through a substituted template
parameter type to see what's behind it, so that we don't end up
printing silly things like "float const *" when "const float *" would
make more sense. Also, replace the pile of "isa" tests with a simple
switch enumerating all of the cases, making a few more obvious cases
use prefix qualifiers.

llvm-svn: 125729
2011-02-17 06:52:25 +00:00
Douglas Gregor 4d5c297607 Tweak my fix for PR8748, and update the incorrect PR number in the test case.
llvm-svn: 124863
2011-02-04 12:22:53 +00:00
Douglas Gregor a99fb4c77d Tighten up the semantics of default template arguments, per C++0x
[temp.param]p9 and C++ DR226. Fixes PR8747.

llvm-svn: 124856
2011-02-04 04:20:44 +00:00
Douglas Gregor 8b481d8ac2 When a function template's template parameter has a default argument,
it's okay for the following template parameters to not have default
arguments (since those template parameters can still be
deduced). Also, downgrade the error about default template arguments
in function templates to an extension warning, since this is a
harmless C++0x extension.

llvm-svn: 124855
2011-02-04 03:57:22 +00:00
Douglas Gregor 0693defea9 When we run into a template parameter that should have a default
argument but doesn't (because previous template parameters had default
arguments), clear out all of the default arguments so that we maintain
the invariant that a template parameter has a default argument only if
subsequence template parameters also have default arguments.
Fixes a crash-on-invalid <rdar://problem/8913649>.

llvm-svn: 124345
2011-01-27 01:40:17 +00:00
Douglas Gregor 54e462ac6e Rvalue references for *this: tentative parsing and template argument deduction.
llvm-svn: 124295
2011-01-26 16:50:54 +00:00
Douglas Gregor 85f240c788 Implement the rvalue-reference deduction transformation (from T&& ->
T) when taking the address of an overloaded function or matching a
specialization to a template (C++0x [temp.deduct.type]p10). Fixes
PR9044.

llvm-svn: 124197
2011-01-25 17:19:08 +00:00
Anders Carlsson e973899f46 A member function template cannot be virtual.
llvm-svn: 124031
2011-01-22 14:43:56 +00:00
Douglas Gregor 6381402fe1 Implement core issue 1164, which concerns the partial ordering of
f(T&) and f(T&&).

llvm-svn: 123981
2011-01-21 17:29:42 +00:00
Douglas Gregor 4edf1c8968 More testing to C++0x [temp.deduct.call]p3
llvm-svn: 123967
2011-01-21 05:24:25 +00:00
Douglas Gregor cba72b1f62 Implement the special template argument deduction rule for T&& in a
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
2011-01-21 05:18:22 +00:00
Douglas Gregor 6edd977c6f Explicitly track the number of call arguments provided when performing
overload resolution, so that we only use that number of call arguments
for partial ordering. Fixes PR9006, a recent regression.

llvm-svn: 123861
2011-01-19 23:54:39 +00:00
Douglas Gregor 476e3029ec Implement basic support for the use of variadic templates and blocks
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
2011-01-19 21:32:01 +00:00
Douglas Gregor 0231d8dac7 Implement support for non-type template parameter packs whose type is
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
2011-01-19 20:10:05 +00:00
Douglas Gregor cef1a03eb5 Tweak the partial ordering rules for function templates to prefer a
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
2011-01-16 16:03:23 +00:00
Douglas Gregor 5590be0491 Introduce a new kind of TemplateName that captures a substituted
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
2011-01-15 06:45:20 +00:00
Douglas Gregor cdbc539aee Introduce a new expression kind, SubstNonTypeTemplateParmPackExpr,
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
2011-01-15 01:15:58 +00:00
Douglas Gregor e1d60df0fc Teach template template argument pack expansions to keep track of the
number of expansions, when we know it, and propagate that information
through Sema.

llvm-svn: 123493
2011-01-14 23:41:42 +00:00
Douglas Gregor 715e461463 Handle substitutions into function parameter packs whose patterns
contain multiple parameter packs at different levels.

llvm-svn: 123488
2011-01-14 22:40:04 +00:00
Douglas Gregor b884000ba9 Teach PackExpansionExpr to keep track of the number of pack expansions
it will expand to, if known. Propagate this information throughout Sema.

llvm-svn: 123470
2011-01-14 21:20:45 +00:00
Douglas Gregor 9f40713ebc When we're instantiating a direct variable initializer that has a pack
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
2011-01-14 17:12:22 +00:00
Douglas Gregor 0dca5fdb4e Keep track of the number of expansions to be produced from a type pack
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
2011-01-14 17:04:44 +00:00
Douglas Gregor ada4b79947 Start implementing support for substitution into pack expansions that
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
2011-01-14 02:55:32 +00:00
Douglas Gregor 018778af3d Only apply the parameter pack matching of C++0x [temp.arg.template]p3
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
2011-01-13 18:47:47 +00:00
Douglas Gregor 0f836ea213 Allow us to transform pack expansion expressions.
llvm-svn: 123349
2011-01-13 00:19:55 +00:00
Douglas Gregor fd4344b5a6 Implement C++0x [temp.arg.template]p3, which allows slightly fuzzy
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
2011-01-13 00:08:50 +00:00
Douglas Gregor ab2ecacee1 Add some more partial-ordering tests, including one that changes with
the proposed resolution to core isue 692. I'm not certain which way
we'll go on this one.

llvm-svn: 123331
2011-01-12 22:04:05 +00:00
Douglas Gregor 822d030118 Teach TreeTransform how to transform a pack expansion type into
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
2011-01-12 17:07:58 +00:00
Douglas Gregor 2fcb863b2b Implement partial ordering of class template partial specializations
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
2011-01-11 22:21:24 +00:00
Douglas Gregor 552c7cf22c Add another test for [temp.func.order]p5/[temp.deduct.partial]p11,
from James Widman.

llvm-svn: 123245
2011-01-11 17:51:55 +00:00
Douglas Gregor b837ea4eee Implement C++ [temp.func.order]p5 more directly, by passing down the
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
2011-01-11 17:34:58 +00:00
Douglas Gregor 7a7dc6f504 Add example from C++0x [temp.deduct.type]p21, which already works
llvm-svn: 123237
2011-01-11 15:36:52 +00:00
Douglas Gregor 5cde386e5e When mapping from a function parameter pack to the set of function
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
2011-01-11 03:14:20 +00:00
Douglas Gregor 0dd423ef33 Implement the last bullet of [temp.deduct.type]p5 and part of the last
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
2011-01-11 01:52:23 +00:00
Douglas Gregor 180dda9b6e Make sure that we parse a '>>' that closes two template argument lists
appropritely when there are no other template arguments.

llvm-svn: 123204
2011-01-11 00:45:18 +00:00
Douglas Gregor 8008ba75a5 Add testing for unexpanded parameter packs in all of the C++
expression kinds. This is (indirectly) a test verifying that the
recursive AST visitor is visiting the children of these expression
nodes.

llvm-svn: 123198
2011-01-11 00:27:36 +00:00
Douglas Gregor 48d2411597 Implement more of C++0x [temp.arg.explicit]p9, allowing extension of
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
2011-01-10 20:53:55 +00:00
Douglas Gregor a8bac7f514 Work-in-progress implementation of C++0x [temp.arg.explicit]p9, which
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
2011-01-10 07:32:04 +00:00
Douglas Gregor b41e2d9298 Variadic templates example: a nearly-complete implementation of a TR1
function class template. 

llvm-svn: 123024
2011-01-07 19:56:20 +00:00
Douglas Gregor fe6e33a3c5 Variadic templates example: a nearly-complete implementation of a TR1
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
2011-01-07 19:37:08 +00:00
Douglas Gregor f30101186f Implement substitution of a function parameter pack for its set of
instantiated function parameters, enabling instantiation of arbitrary
pack expansions involving function parameter packs. At this point, we
can now correctly compile a simple, variadic print() example:

  #include <iostream>
  #include <string>

  void print() {}

  template<typename Head, typename ...Tail>
  void print(const Head &head, const Tail &...tail) {
    std::cout << head;
    print(tail...);
  }

  int main() {
    std::string hello = "Hello";
    print(hello, ", world!", " ", 2011, '\n');
  }

llvm-svn: 123000
2011-01-07 16:43:16 +00:00
Douglas Gregor dd47216cc4 Factor out the template transformation of a sequence of function
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
2011-01-07 00:20:55 +00:00
Douglas Gregor 7825bf3a12 Implement template argument deduction from a call to a function
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
2011-01-06 22:09:01 +00:00
Douglas Gregor 5499af4ef9 Initial implementation of function parameter packs. This implementation allows:
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
2011-01-05 23:12:31 +00:00
Douglas Gregor 51bc571955 When we're converting deduced template arguments to the type of the
corresponding template parameter, make sure that prior converted
template arguments are available for substitution.

llvm-svn: 122902
2011-01-05 20:52:18 +00:00
Douglas Gregor e4ff4b56fe Replace the representation of template template argument pack
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
2011-01-05 18:58:31 +00:00