[Bug libstdc++/37347] New: valarray::operator[](slice) const returns wrong type.

["crazydm at gmail dot com" <gcc-bugzilla at gcc dot gnu dot org>]

valarray::operator[](slice) const returns _Expr<_SClos<_ValArray,_Tp>, _Tp>
instead of slice_array<Tp>, this type cannot be casted (with static_cast) to
slice_array<Tp>.

gcc barfs that
"conversion from ?std::_Expr<std::_SClos<std::_ValArray, double>, double>? to
non-scalar type ?std::slice_array<double>? requested"

This concerns only const version of the operator[](slice), normal version works
fine. So slice_array objects cannot be created using const valarray objects.

P.S. const_cast can be used as a workaround.

The example program is attached.


-- 
           Summary: valarray::operator[](slice) const returns wrong type.
           Product: gcc
           Version: 4.3.1
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: libstdc++
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: crazydm at gmail dot com
 GCC build triplet: Using built-in specs.
  GCC host triplet: GNU/Linux alioth 2.6.25-ARCH #1 SMP PREEMP
GCC target triplet: i686-pc-linux-gnu


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=37347