[XLC++ 7.0, 8.0, 9.0] warning 1540-0183 on explicit instantiation

• Key: STDCXX-367
• Type: Bug
• Status: Resolved
• Resolution: Cannot Reproduce
• Priority: Minor
• Assignee: Travis Vitek
• Reporter: Martin Sebor
• Component/s: Build and Installation
• Affects Version/s: 4.1.3
• Fix Version/s: 4.2.2

Description

Compiling stdcxx 4.1.3 with XLC++ 7.0 on AIX produces many warnings like the ones below:

xlCcore -c -I/amd/devco/sebor/stdcxx-4.1.3/include/ansi -D_RWSTDDEBUG -D_RWSTD_USE_CONFIG -I/build/sebor/stdcxx-4.1.3-xlc-7.0.0.9-11s/include -I/amd/devco/sebor/stdcxx-4.1.3/include -g -qtemplateregistry=repository.ti /amd/devco/sebor/stdcxx-4.1.3/src/ti_istream.cpp
"/amd/devco/sebor/stdcxx-4.1.3/include/istream", line 580.23: 1540-0183 (W) The explicit instantiation "basic_istream<char,std::char_traits<char> >" should either be explictly qualified or be declared in the namespace containing the template.
"/amd/devco/sebor/stdcxx-4.1.3/include/istream", line 580.23: 1540-0183 (W) The explicit instantiation "basic_istream<char,std::char_traits<char> >" should either be explictly qualified or be declared in the namespace containing the template.
"/amd/devco/sebor/stdcxx-4.1.3/include/istream", line 153.16: 1540-0700 (I) The previous message was produced while processing "_rw::_rw_extract<char,std::char_traits<char>,bool>(basic_istream<char,std::char_traits<char> > &, bool &)".
"/amd/devco/sebor/stdcxx-4.1.3/include/istream", line 152.20: 1540-0700 (I) The previous message was produced while processing "std::basic_istream<char,std::char_traits<char> >::operator>>(bool &)".
"/amd/devco/sebor/stdcxx-4.1.3/include/istream", line 82.7: 1540-0700 (I) The previous message was produced while processing "class std::basic_istream<char,std::char_traits<char> >".
...

Comments

[Martin Sebor]

This is a problem across all versions from 7.0 through 9.0.

[Martin Sebor]

I don't see the warnings in recent builds or in builds with 4.2.0.
Travis, can you confirm that we are haven't accidentally disabled explicit instantiation and close this issue if it's been fixed?

[Travis Vitek]

The templates are being explicitly instantiated. The basic_istream<char> symbols are all in the lib. If I preprocess ti_ostream.cpp I see the following code...

namespace std {
  template class basic_istream<char, char_traits<char> >;
}

I do see some conditional code in rw/_defs.h that disables explicit instantation to avoid an ICE with XLC++ 8.0. This is only enabled under very specific conditions and would not have an impact on other versions of the compiler.