Very Computer

backround info: I'm building an application in standard compat=5 mode, Sun
Workshop 5.0
  I have a set of 3rd party libraries which were built with Sun Workshop 4.2
  These libraries depend in libC. My application depends on libCrun.

  Question: Does it make sense to link both libC and libCrun ?

  When I try and link both libC and libCrun, I get multiply defined symbols,
ie  _ex_register defined in
both libC and libCrun.

Thanks in advance.

Jeff

Linking together ARM (4.2 or -compat=4) C++ code
and ANSI/ISO (5.0 with -compat=4) C++ code will
usually *not* work, because of duplicate or
unresolved symbols at various places (the ABI is different).

The only way you could possibly get this to work is
- exception handling only either in the -compat=4 or the
  -compat=5 part of the code (otherwise
   duplicate symbols here, too)
- the interface between both parts is a pure C interface

Compare the C++ migration guide

Thomas

Quote:> The only way you could possibly get this to work is
> - exception handling only either in the -compat=4 or the
>   -compat=5 part of the code (otherwise
>    duplicate symbols here, too)
> - the interface between both parts is a pure C interface

> Compare the C++ migration guide

Interface description:
Apllication code ( compat=5) invokes extern "C" functions ( which are built
in mode=4).
These extern "C" function are the only place where the 3rd party library
calls are invoked.

Exception handling:
Exeption handling is being used in both parts of the code.  But the extern
"C" functions never
throw an exception and they should catch all exceptions.  However, this is
what I don't
understand.  In the "C++ migration guide, section Mixing Old and New
Binaries" it specifies that
..."No C++ exceptions escape from or are passed into the library"

I believe this is satisfied since it is the extern "C" functions ( compat=4)
which catch the exception being
thrown by the 3rd party libraries. The extern "C" functions translate the
exception into a return code to
the application.

Esentially the C++ Migration Guide does not specify that exception handling
can only be used
in only one part of the code.  Is Sun documention wrong ?  Maybe I have to
use special linking
order. Something like:

link application_code.o -lCrun externCfunctions.o -l3rdPartyLibs.a -lC

Regards,

Jeff

Also no objects can be passed as parameters to those
functions etc. pp.

Quote:> Exception handling:
> Exeption handling is being used in both parts of the code.
> But the extern "C" functions never
> throw an exception and they should catch all exceptions.

This is insufficient.
-compat=4 and -compat=5 create internal symbols
for the exception handling some of which will have the same
names.

Quote:> Esentially the C++ Migration Guide does
> not specify that exception handling can only be used
> in only one part of the code.  Is Sun documention wrong ?

This issue is documented only incompletely
in the C++ Migration Guide from C++ 5.0,
but correctly somewhere in the C++ 5.1 documentation.

Thomas