libstdc++: Fix std::common_iterator triviality [PR100823]

This fixes the remaining problem reported in the PR, that the special
members should be trivial.  This can be done by constraining the
non-trivial versions and adding defaulted overloads that will be used
when the union members are trivial.

Making these members trivial alters the argument passing ABI and so
isn't suitable for backporting to release branches.

libstdc++-v3/ChangeLog:

	PR libstdc++/100823
	* include/bits/stl_iterator.h (common_iterator): Define
	destructor, copy constructor and move constructor as trivial
	when the underlying types allow.
	* testsuite/24_iterators/common_iterator/100823.cc: Check
	triviality of special members.

0 files changed, 0 insertions, 0 deletions