[Bug libstdc++/93059] char and char8_t does not talk with each other with memcpy. std::copy std::copy_n, std::fill, std::fill_n, std::uninitialized_copy std::uninitialized_copy_n, std::fill, std::uninitialized_fill_n fails to convert to memxxx functions

[euloanty at live dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=93059

--- Comment #29 from fdlbxtqi <euloanty at live dot com> ---
(In reply to Marc Glisse from comment #17)
> (In reply to fdlbxtqi from comment #15)
> > What I am worried about is that whether revamping these functions would be 
> > a new wave of ABI breaking.
> 
> I don't foresee any ABI issue here. Do make sure your code doesn't break
> with -std=c++03, and run the testsuite before submitting it.

I think the test suite has passed. However, I am not sure since I have never
used dejagnu before.

It looks like these test suites will fail in some cases even without my patch.
(filesystem, network ts for example)

I need you to check them.