[Bug libstdc++/54314] [4.8 Regression] undefined references to 'construction vtable for std::ostream-in-std::basic_ostringstream<char, std::char_traits<char>, std::allocator<char> >'

[jakub at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54314

--- Comment #32 from Jakub Jelinek <jakub at gcc dot gnu.org> 2013-02-04 10:22:36 UTC ---
(In reply to comment #31)
> The patch seems to have broken many testcases on platforms like Solaris 9 with
> Sun as that lack visibility support:
> 
> FAIL: g++.dg/abi/covariant2.C -std=c++98 (test for excess errors)
> Excess errors:
> /vol/gcc/src/hg/trunk/local/gcc/testsuite/g++.dg/abi/covariant2.C:31:20:
> warning
> : visibility attribute not supported in this configuration; ignored
> [-Wattribute
> s]
> /vol/gcc/src/hg/trunk/local/gcc/testsuite/g++.dg/abi/covariant2.C:31:20:
> warning
> : visibility attribute not supported in this configuration; ignored
> [-Wattribute
> s]

That's very weird, because build_vtable marks the vtable decl as
DECL_ARTIFICIAL
and thus it shouldn't be warned about.  Or is it some other decl that copies
the visibility from the construction vtable decl?