Re: [MLB] Patch: Check for GNU nm under AIX 4 and 5

[Alexandre Oliva]

And, given that you're playing with AIX and I believe you have been in
touch with folks at IBM that do understand the workings of shared
libraries there...

I've just found out why gcc -shared (and a shared libstdc++) wouldn't
work in with GCC 2.95.2.  GCC's collect implicitly creates an import
file whose files line is `#! .'.  On AIX 4.1, this causes the library
to depend on `.'; on 4.3, `.' is handled especially.  I'd like to know
whether this works on 4.2, but I don't have access to any such
system.  Would you mind asking folks over there?

My plan is to set deplibs_check_method=none for releases of GCC
earlier than 2.97.x (currently development snapshots of GCC no longer
generate these import files).  My currently-being-tested patch does
something like this in AIX's section of ltconfig:

    if { echo '#if __GNUC__ > 2 || (__GNUC__ == 2 && __GNUC__ >= 97)'
         echo ' yes '
         echo '#endif'; } | ${CC} -E - | grep yes > /dev/null; then
      # With GCC up to 2.95.x, collect2 would create an import file
      # for dependence libraries.  The import file would start with
      # the line `#! .'.  This would cause the generated library to
      # depend on `.', always an invalid library.  This was fixed in
      # development snapshots of GCC prior to 3.0.
      deplibs_check_method=pass_all
    else
      # If we have an older version of GCC, disable dependence libraries.
      deplibs_check_method=none
    fi

I'd like to start the `if' with something that indicates
deplibs_check_method=pass_all for AIX 4.3 or newer, and maybe for 4.2,
if its linker handles `#! .' especially in -bI: import files.

-- 
Alexandre Oliva   Enjoy Guarana', see http://www.ic.unicamp.br/~oliva/
Red Hat GCC Developer                  address@hidden, redhat.com}
CS PhD student at IC-Unicamp        address@hidden, gnu.org}
Free Software Evangelist    *Please* write to mailing lists, not to me