On Fri, 15 Sep 2017, Johan Alfredsson wrote:
I ran into a symbol name difference linking an executable compiled with
clang 5.0 vs. compiling with gcc 7.1.0 on Solaris/SPARC.
In bits/locale_facets_nonio.tcc, there is the following template:
template<typename _CharT, typename _OutIter>
_OutIter
time_put<_CharT, _OutIter>::
put(iter_type __s, ios_base& __io, char_type __fill, const tm* __tm,
const _CharT* __beg, const _CharT* __end) const
Looking at the symbol in libstdc++.so corresponding to the instantiation of
time_put<char, std::ostreambuf_iterator<char, std::char_traits<char>>>, it
is
_ZNKSt8time_putIcSt19ostreambuf_iteratorIcSt11char_
traitsIcEEE3putES3_RSt8ios_basePK2tmPKcSB_
This corresponds to (according to c++filt):
std::time_put<char, std::ostreambuf_iterator<char, std::char_traits<char> >
::put(std::ostreambuf_iterator<char, std::char_traits<char> >,
std::ios_base&, tm const*, char const*, char const*) const
Now, linking the executable compiled with clang 5.0 results in an error
about a missing symbol. That symbol is:
std::time_put<char, std::ostreambuf_iterator<char, std::char_traits<char> >
::put(std::ostreambuf_iterator<char, std::char_traits<char> >,
std::ios_base&, std::tm const*, char const*, char const*) const
where the difference is that the type tm is now std::tm.
It seems to me that std::tm should be the proper type here, but I might be
wrong.
Comments?
This was done on purpose when we changed __cplusplus from 1 to 199711, to
avoid breaking the ABI. On Solaris, we will mangle std::tm as if it was
::tm until the next ABI break (probably not soon).
--
Marc Glisse
