[Bug c++/53954] [C++11] Undefined reference to non-odr-used static const member variable of variadic class template in DSO with -flto and -Wl,--export-dynamic

[redi at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=53954

--- Comment #4 from Jonathan Wakely <redi at gcc dot gnu.org> 2012-07-16 
20:55:02 UTC ---
(In reply to comment #0)
> Note also that the above reproducer originally comes from a likely C++ code
> using `std::vector' and `-std=c++11' option, like the following;
> 
> /////////////////////
> #include <vector>
> 
> void f()
> {
>   std::vector<int> v;
>   v.push_back(0);
> }
> /////////////////////
> 
> When a DSO is created from this code with `-std=c++11', `-lfto' and
> `-Wl,--export-dynamic' options, it requires the definition of
> `std::allocator_traits<std::allocator<int> >::__construct_helper<int,
> int>::value'.

I have no view on whether this PR is valid or not, but the std::vector failure
is fixed for 4.7.2