[Bug c++/51832] [4.7 regression] Rev.182970 causes LTO link errors (multiple definitions of allocator_traits)

[jason at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=51832

--- Comment #4 from Jason Merrill <jason at gcc dot gnu.org> 2012-01-12 
15:25:55 UTC ---
(In reply to comment #2)
> error: /tmp/ccZEKdVj.o: multiple definition of
> '_ZNSt16allocator_traitsISaIiEE18__construct_helperIiJiEE5valueE'

That symbol is an extra-name alias for

std::allocator_traits<std::allocator<int> >::__construct_helper<int,
int>::value

created by mangle_decl for forward ABI compatibility.

But I can't reproduce the bug; that variable isn't emitted at all when I
compile the reduced testcase with r183124.