Re: [RFA] Fix for sparc-lynxos build

["David S. Miller" <davem at redhat dot com>]

   From: Michael Snyder <msnyder@redhat.com>
   Date: Tue, 23 Apr 2002 12:05:36 -0700

   "David S. Miller" wrote:
   > 
   > remote.c, if SOLIB_CREATE_INFERIOR_HOOK is define, calls
   > no_shared_libraries.  sparc-lynxos uses coff-solib.c which
   > does not provide this function, thus the final link of the
   > build fails.
   > 
   > This adds a dummy definition so at least this target can link
   > successfully, but keep a FIXME comment there so that this gets
   > some attention in the future.
   > 
   > Ok to install?
   
   I'm worried that, once this goes in, it may never get fixed.
   How about at least making it print a warning?
   
   > 
   > 2002-04-21  David S. Miller  <davem@redhat.com>
   > 
   >         * coff-solib.c (no_shared_libraries): Add dummy implementation.
   > 

I looked some more into this, and there are many other problems
to do with this function.

First of all, if we add an implementation to coff-solib.c we
have a problem for the rs6000lynx configuration because:

config/rs6000/rs6000lynx.mt:TDEPFILES= coff-solib.o rs6000-tdep.o ppc-linux-tdep.o solib.o solib-svr4.o

This brings in both coff-solib.o and solib.o, thus we would end up
with two instances of this symbol and the build would fail....
Well, even now rs6000-lynxos fails to link for other reasons:

libgdb.a(buildsym.o): In function `end_symtab':
_SC_REALTIME_SIGNALS/../../src/gdb/buildsym.c:951: undefined reference to `aix_process_linenos'

Oops.

Not only that, this situation exists already via xcoffsolib.o,
consider:

config/rs6000/rs6000.mh:             xcoffsolib.o
config/rs6000/rs6000.mt:TDEPFILES= rs6000-tdep.o xcoffread.o ppc-linux-tdep.o solib.o solib-svr4.o

Ie. this configuration brings in both xcoffsolib.o (which has an empty
no_shared_libraries implementation) as well as solib.o (which has a
real implementation).  This should cause a build failure too.

It seems that implementing no_shared_libraries for xcoffsolib.c and
coff-solib.c with just a call to objfile_purge_solibs() would be
correct.

However, maybe an even more correct solution is to not have any
implementation in xcoffsolib.c and coff-solib.c.  Then add solib.o
to the appropriate target makefile fragments.

Comments?