C++ err msgs [ was Re: building libstdc++-v3 from the 20000105 snapshot dies with multiple def errors. ]

[Gabriel Dos Reis]

Benjamin Kosnik <bkoz@cygnus.com> writes:

| you can try 
| 
| -fmessage-length=WIDTH
| 
| where WIDTH is a length substituted by you.
| 
| Gaby did a bunch of work on this kind of stuff, so I'll let him give a 
| more authoritative answer.

-fmessage-length only affects line widths.  It doesn't have any effect
on other formatting aspects (for example, it doesn't tell anything
about whether default template-argument are displayed or not).

One of the problems lies in the fact that G++ applies a single flag to
tell whether declarations should be verbose or not.  Under what
circumstances default template arguments should be displayed isn't
that obvious.  Any suggestion is welcome.

Parts of cp/errors.c are being rewritten to take advantage of the possibility

| I believe this part of the original mail was human-constructed: if not, 
| I'd like to know how to get g++ to format like this (exact command line 
| please)
| 
| .libs/libinst-string.al(stringCTORDUPAL.lo): In 
| function `std::messages_base type_info function':
| /usr/building/libstdc++-devel/gcc-2.95.2.objdir/i686-pc-linux-gnu/libstdc++/src/../../../../gcc-2.95.2/libstdc++/bits/st
| ring.tcc:54:
| multiple definition of
| `
| std::basic_string
| <
|   char,
|   std::char_traits<char>,
|   std::allocator<char>
| >::basic_string(unsigned int, char, std::allocator<char> const &)
| 
| 
| Would be cool if all the messages looked like this......

Is this Gnucally correct? Note that I don't have trouble to implement
thus scheme (since parts of cp/errors are being rewritten in order to
be easily parameterized by formatting standards) but I need to know
that it won't be thrown away.

-- Gaby
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