[v3 PATCH] nonesuch is insufficiently useless (lwg2996)

[Nina Dinka Ranns]

Tested on Linux x86_64
nonesuch is insufficiently useless (lwg2996)

2019-05-14  Nina Dinka Ranns  <dinka.ranns@gmail.com>
        nonesuch is insufficiently useless (lwg2996)
        * include/std/type_traits
        struct __nonesuch: added private base class to make __nonesuch
not an aggregate and removed deleted default constructor
        * include/bits/stl_pair.h:
        struct __nonesuch_no_braces: Removed
        (operator=(const pair&)): Use __nonesuch instead of
__nonesuch_no_braces.
        (operator=(pair&&)): Likewise
        * include/std/tuple
        (operator=(const tuple&)): Use __nonesuch instead of
__nonesuch_no_braces.
        (operator=(tuple&&)): Likewise
        * include/experimental/type_traits
         struct nonesuch: added private base class to make nonesuch
not an aggregate and removed deleted default constructor
        * testsuite/20_util/nonesuch/nonesuch.cc: New
        * testsuite/experimental/type_traits/nonesuch.cc: New
-------------- next part --------------
A non-text attachment was scrubbed...
Name: lwg2960.diff
Type: text/x-patch
Size: 7358 bytes
Desc: not available
URL: <http://gcc.gnu.org/pipermail/libstdc++/attachments/20190514/e740304d/attachment.bin>