[Bug c++/54026] New: [4.7/4.8 regression] template const struct with mutable members erroneously emitted to .rodata

["ppluzhnikov at google dot com" <gcc-bugzilla at gcc dot gnu dot org>]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54026

             Bug #: 54026
           Summary: [4.7/4.8 regression] template const struct with
                    mutable members erroneously emitted to .rodata
    Classification: Unclassified
           Product: gcc
           Version: unknown
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: ppluzhnikov@google.com


Reproduced with 4.7 and current trunk:
g++ (GCC) 4.8.0 20120719 (experimental)

// --- cut here ---
void non_const(int *);

template <typename T>
struct Foo {
  T x;
  mutable int y;
  void func() const { non_const(&y); }
};

struct Bar {
  int x;
  mutable int y;
  void func() const { non_const(&y); }
};

const Foo<int> foo = { 1, 2 };
const Bar bar = { 3, 4 };
// --- cut here ---

Results in:

    .data
    .align 4
    .type    _ZL3bar, @object
    .size    _ZL3bar, 8
_ZL3bar:
    .long    3
    .long    4

    .section    .rodata
    .align 4
    .type    _ZL3foo, @object
    .size    _ZL3foo, 8
_ZL3foo:
    .long    1
    .long    2


But it is a bug to place "foo" into .rodata, since it contains a mutable
member.