Avoid tests failures in C++98

[Jonathan Wakely]

On 30/10/18 22:42 +0100, François Dumont wrote:
>Running some tests in C++98 show that the error checked by following 
>tests are those of the C++11 mode.
>
>This patch add target c++11 so that those tests are ignored in 
>previous mode.
>
>Â Â Â  * testsuite/23_containers/deque/requirements/dr438/assign_neg.cc:
>Â Â Â  Add target c++11.
>Â Â Â  * 
>testsuite/23_containers/deque/requirements/dr438/constructor_1_neg.cc:
>Â Â Â  Likewise.
>Â Â Â  * 
>testsuite/23_containers/deque/requirements/dr438/constructor_2_neg.cc:
>Â Â Â  Likewise.
>Â Â Â  * testsuite/23_containers/deque/requirements/dr438/insert_neg.cc:
>Â Â Â  Likewise.
>
>Ok to commit ?

No, because then we wouldn't test those members in C++98.

We should either duplicate the tests and have one copy using
{ target c++11 } and the other using { dg-options "-std=gnu++98" }, or
we should fix the expected errros to work for C++98 too. I have local
patches to do the latter, that I haven't submitted yet.