[Bug libstdc++/103387] powerpc64le: segmentation fault on std::cout with ieee128 long double variable

[redi at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103387

--- Comment #8 from Jonathan Wakely <redi at gcc dot gnu.org> ---
And that's because we're using the ostream's cached _M_num_put but that is the
wrong one:

(gdb) step
std::basic_ostream<char, std::char_traits<char> >::_M_insert<__ieee128>
(this=0x101c0900 <std::cout>, __v=0.100000000000000000000000000000000005)
    at
/home/test/build/powerpc64le-unknown-linux-gnu/libstdc++-v3/include/bits/ostream.tcc:66
66              sentry __cerb(*this);
(gdb) n
67              if (__cerb)
(gdb) 
69                  ios_base::iostate __err = ios_base::goodbit;
(gdb) 
72                      const __num_put_type& __np =
__check_facet(this->_M_num_put);
(gdb) p _M_num_put
$18 = (const std::basic_ios<char, std::char_traits<char> >::__num_put_type *)
0x101c1f98 <(anonymous namespace)::num_put_c>