[omniORB] Linking problems in MSVC++ 5.0

[Dee Jay Randall]

  Hmmm. I've only installed omniORB 2.6.1. I don't know how I could
possibly have gotten pre-2.6.x runtime libraries. And I don't get
an undefined symbol: omniORB_2_6.

  I get 31 LINK2001: unresolved external symbol "blahblah" errors.
None of them are for the symbol omniORB_2_6.

  I downloaded omniORB_2_6_1_x86_win32.zip on November 4, so I can't
see old files as the problem. I am re-downloading the files just to be
sure. I would be surprised if that is the problem.

  I can find omniORB_2_6 in omniinternal.h, and my application
doesn't complain about not finding it, so I think it is finding
that symbol no problem.

  Looking inside some of the include files.... Perhaps
"HAS_Cplusplus_Namespace" is not being defined somehow?

  Thanks,

  Dee Jay Randall       _-~-_-~-_-~-_-~-_-~-_-~-_-~-_-~-_-~-_-~-_-~-_-~-_-~-_
  randal@cs.uregina.ca  |  "While reality is neither black and white nor    |
                       { }  right and wrong, those are the only ideals     { }
   _-__-_  ouch,       { }  against which we can evaluate our decisions."  { }
  >      <  that hurt   |                                    -me            |
_)  chomp (___________  ~-_-~-_-~-_-~-_-~-_-~-_-~-_-~-_-~-_-~-_-~-_-~-_-~-_-~

On 9 Nov 1998, Sai-Lai Lo wrote:

> >>>>> Dee Jay Randall writes:
> >
> >   I did manage to build the echo example, and it worked fine.
> > Yes, in eg1.obj, the external symbol name of CORBA::string_free
> > is ?string_free@CORBA@@YAXPAD@Z
> >
> >   Here is what I get when I do a dumpbin on eg1.obj and server.obj
> > (server.obj is my file that is causing the trouble):
> >
> > eg1.obj:
> > 024 00000000 UNDEF  notype ()    External     | ?string_free@CORBA@@YAXPAD@Z
> > (void __cdecl CORBA::string_free(char *))
> >
> > server.obj:
> > 051 00000000 UNDEF  notype ()    External     | ?string_free@CORBA@@SAXPAD@Z
> > (public: static void __cdecl CORBA::string_free(char *))
> >
> >   The "public: static" part is obviously the problem (right?), but how
> > do I get rid of it?
> 
> I think I know what is wrong. Do you have a pre-2.6.x version in your
> development tree? I think when you built server.obj, the omniORB2 header
> files from a pre-2.6.x distribution got included instead of the 2.6.x
> headers.
> 
> One of the changes in 2.6.x is the use of C++ namespace to represent CORBA
> modules when compiled with MSVC++. This is why the signature of
> CORBA::string_free is now:
>      void __cdecl CORBA::string_free(char *);
> 
> In pre-2.6.x versions, CORBA is a C++ class, hence the signature of
> CORBA::string_free is:
> 
>    public: static void __cdecl CORBA::string_free(char *)
> 
> 
> By the way, there is a guard against accidentally linking stubs generated
> by the 2.6.x omniidl2 with the pre-2.6.x runtime. The linkage would fail at
> least with the undefined symbol omniORB_2_6, which is only present in the
> 2.6.x runtime. In your case, this undefined symbol must have been hidden by
> the hundreds of undefined symbols causes by the namespace change.
> 
> Obviously, you just have to remove the old headers from your development
> tree and make sure that the 2.6.x headers are picked up.
> 
> 
> Tell us if this solves your problem.
> 
> 
> Regards,
> 
> Sai-Lai
> 
> 
> -- 
> Dr. Sai-Lai Lo                          |       Research Scientist
>                                         |
> E-mail:         S.Lo@orl.co.uk          |       Olivetti & Oracle Research Lab
>                                         |       24a Trumpington Street
> Tel:            +44 223 343000          |       Cambridge CB2 1QA
> Fax:            +44 223 313542          |       ENGLAND
>