[Bug c++/52292] New: [C++11] Variadic template expansion into fixed template causes constructor to not match

[Bug c++/52292] New: [C++11] Variadic template expansion into fixed template causes constructor to not match

[leckey.ryan at gmail dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=52292

             Bug #: 52292
           Summary: [C++11] Variadic template expansion into fixed
                    template causes constructor to not match
    Classification: Unclassified
           Product: gcc
           Version: 4.7.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: leckey.ryan@gmail.com


The following should compile but fails with several errors about declaration
errors.

template <template <typename...> class T>
struct foo {
    template <typename... U>
    foo(T<U...> x) { }
};

template <typename T>
struct bar {
    bar(T x) : value(x) { }

    T value;
};

struct generic : private foo<bar> {
    template <typename T>
    generic(bar<T> x) : foo(x)
    {
    }

};

int main()
{
    bar<int> x(32);
    generic y(x); // FAILS
}

If you remove the '...' then everything works.

[Bug c++/52292] [C++11] Variadic template expansion into fixed template causes constructor to not match

[leckey.ryan at gmail dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=52292

--- Comment #1 from Ryan Leckey <leckey.ryan at gmail dot com> 2012-02-17 01:00:33 UTC ---
Oops, forgot this.

Here is the output of `gcc -v`

Using built-in specs.
COLLECT_GCC=l:\Applications\MinGW\bin\gcc.exe
COLLECT_LTO_WRAPPER=l:/applications/mingw/bin/../libexec/gcc/i686-pc-mingw32/4.7.0/lto-wrapper.exe
Target: i686-pc-mingw32
Configured with: ../../mingw-src/gcc-trunk/configure --host=i686-pc-mingw32
--build=i686-pc-mingw32 --target=i686-pc-mingw32 --prefix=/mingw-dwarf-x86
--with-arch=i686 --with-tune=generic --enable-languages=c,c++,lto,fortran
--enable-libstdcxx-time=yes --with-host-libstdcxx=-lstdc++ --enable-shared
--enable-static --enable-libgomp --enable-lto --enable-graphite
--enable-cloog-backend=isl --enable-checking=release
--enable-fully-dynamic-string --enable-threads=posix --disable-libstdcxx-pch
--enable-libstdcxx-debug --disable-sjlj-exceptions --with-dwarf2
--disable-debug --disable-bootstrap --disable-multilib --disable-rpath
--disable-win32-registry --disable-nls --disable-werror --disable-symvers
--with-gmp=/mingw-libs --with-mpfr=/mingw-libs --with-mpc=/mingw-libs
--with-ppl=/mingw-libs --with-cloog=/mingw-libs
--with-libiconv-prefix=/mingw-libs --with-pkgversion='niXman build'
--with-bugurl=http://code.google.com/p/mingw-builds/issues/list
Thread model: posix
gcc version 4.7.0 20120203 (experimental)

[Bug c++/52292] [C++11] Variadic template expansion into fixed template causes constructor to not match

[jason at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=52292

Jason Merrill <jason at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |ASSIGNED
   Last reconfirmed|                            |2012-04-16
                 CC|                            |jason at gcc dot gnu.org
         AssignedTo|unassigned at gcc dot       |jason at gcc dot gnu.org
                   |gnu.org                     |
     Ever Confirmed|0                           |1

[Bug c++/52292] [C++11] Variadic template expansion into fixed template causes constructor to not match

[jason at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=52292

--- Comment #2 from Jason Merrill <jason at gcc dot gnu.org> 2012-04-16 03:18:13 UTC ---
Author: jason
Date: Mon Apr 16 03:18:06 2012
New Revision: 186479

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=186479
Log:
    PR c++/52292
    PR c++/52380
    * pt.c (coerce_template_parms): Even if we aren't converting we
    want to expand argument packs.

Added:
    trunk/gcc/testsuite/g++.dg/cpp0x/variadic124.C
    trunk/gcc/testsuite/g++.dg/cpp0x/variadic125.C
Modified:
    trunk/gcc/cp/ChangeLog
    trunk/gcc/cp/pt.c
    trunk/gcc/testsuite/ChangeLog

[Bug c++/52292] [C++11] Variadic template expansion into fixed template causes constructor to not match

[jason at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=52292

--- Comment #3 from Jason Merrill <jason at gcc dot gnu.org> 2012-04-16 03:40:38 UTC ---
Author: jason
Date: Mon Apr 16 03:40:34 2012
New Revision: 186481

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=186481
Log:
    PR c++/52292
    PR c++/52380
    * pt.c (coerce_template_parms): Even if we aren't converting we
    want to expand argument packs.

Added:
    branches/gcc-4_7-branch/gcc/testsuite/g++.dg/cpp0x/variadic124.C
    branches/gcc-4_7-branch/gcc/testsuite/g++.dg/cpp0x/variadic125.C
Modified:
    branches/gcc-4_7-branch/gcc/cp/ChangeLog
    branches/gcc-4_7-branch/gcc/cp/pt.c
    branches/gcc-4_7-branch/gcc/testsuite/ChangeLog

[Bug c++/52292] [C++11] Variadic template expansion into fixed template causes constructor to not match

[jason at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=52292

Jason Merrill <jason at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|ASSIGNED                    |RESOLVED
         Resolution|                            |FIXED
   Target Milestone|---                         |4.7.1

--- Comment #4 from Jason Merrill <jason at gcc dot gnu.org> 2012-04-16 03:52:47 UTC ---
Fixed for 4.7.1.