__cxa_pure_virtual

__cxa_pure_virtual

[Sinisa Milivojevic]

Hi!

Sorry for bothering you.

Please CC: a reply to me as I am not a member of the list.

Is there a way of compiling a C++ file, which does not contain any
references to STL classes, so that resultant object file will have no
references to the above symbol, defined in pure.cc of libstdc++.

This is a problem in 3.0[1,2]

I have tried using gcc for CXX, setting -fno-rtti -fno-exceptions, but
still libstdc++ has to be linked in , due to the above symbol.

Any solution or work-around ??


Many thanks in advance.

-- 
Regards,
   __  ___     ___ ____  __
  /  |/  /_ __/ __/ __ \/ /    Mr. Sinisa Milivojevic <sinisa@mysql.com>
 / /|_/ / // /\ \/ /_/ / /__   MySQL AB, Fulltime Developer
/_/  /_/\_, /___/\___\_\___/   Larnaca, Cyprus
       <___/   www.mysql.com

Re: __cxa_pure_virtual

[Nathan Sidwell]

Sinisa Milivojevic wrote:
> Is there a way of compiling a C++ file, which does not contain any
> references to STL classes, so that resultant object file will have no
> references to the above symbol, defined in pure.cc of libstdc++.
Other than by providing definitions of all your abstract functions, no.

> Any solution or work-around ??
You can also link with libsupc++, which contains just the C++ runtime
support routines without the std lib stuff. Or you could define that
symbol explicitly to the linker
	--defsym __cxa_pure_virtual=0
(or, if invoked via gcc)
	-Wl,--defsym -Wl __cxa_pure_virtual=0

nathan

-- 
Dr Nathan Sidwell   ::   http://www.codesourcery.com   ::   CodeSourcery LLC
         'But that's a lie.' - 'Yes it is. What's your point?'
nathan@codesourcery.com : http://www.cs.bris.ac.uk/~nathan/ : nathan@acm.org

Re: __cxa_pure_virtual

[Sinisa Milivojevic]

Nathan Sidwell writes:
> 
> > Any solution or work-around ??
> You can also link with libsupc++, which contains just the C++ runtime
> support routines without the std lib stuff. Or you could define that
> symbol explicitly to the linker
> 	--defsym __cxa_pure_virtual=0
> (or, if invoked via gcc)
> 	-Wl,--defsym -Wl __cxa_pure_virtual=0
> 
> nathan
> 
> -- 
> Dr Nathan Sidwell   ::   http://www.codesourcery.com   ::   CodeSourcery LLC
>          'But that's a lie.' - 'Yes it is. What's your point?'
> nathan@codesourcery.com : http://www.cs.bris.ac.uk/~nathan/ : nathan@acm.org
> 

Thanks. Exactly what I needed. 

I guess I can find libsupc++ on ftp.gnu.org ???

I will try other recommandations too.

Thanks again.

-- 
Regards,
   __  ___     ___ ____  __
  /  |/  /_ __/ __/ __ \/ /    Mr. Sinisa Milivojevic <sinisa@mysql.com>
 / /|_/ / // /\ \/ /_/ / /__   MySQL AB, Fulltime Developer
/_/  /_/\_, /___/\___\_\___/   Larnaca, Cyprus
       <___/   www.mysql.com

Re: __cxa_pure_virtual

[Phil Edwards]

On Fri, Nov 30, 2001 at 07:24:50PM +0200, Sinisa Milivojevic wrote:
> 
> I guess I can find libsupc++ on ftp.gnu.org ???

It's part of GCC 3.0.  If you compiled a C++ compiler, then it should be
possible to only type

    g++ -o a.out ......  -lsupc++

while linking.


Phil

-- 
If ye love wealth greater than liberty, the tranquility of servitude greater
than the animating contest for freedom, go home and leave us in peace.  We seek
not your counsel, nor your arms.  Crouch down and lick the hand that feeds you;
and may posterity forget that ye were our countrymen.            - Samuel Adams

Re: __cxa_pure_virtual

[Phil Edwards]

On Fri, Nov 30, 2001 at 07:24:50PM +0200, Sinisa Milivojevic wrote:
> 
> I guess I can find libsupc++ on ftp.gnu.org ???

It's part of GCC 3.0.  If you compiled a C++ compiler, then it should be
possible to only type

    g++ -o a.out ......  -lsupc++

while linking.


Phil

-- 
If ye love wealth greater than liberty, the tranquility of servitude greater
than the animating contest for freedom, go home and leave us in peace.  We seek
not your counsel, nor your arms.  Crouch down and lick the hand that feeds you;
and may posterity forget that ye were our countrymen.            - Samuel Adams

Re: __cxa_pure_virtual

[Sinisa Milivojevic]

Phil Edwards writes:
> 
> It's part of GCC 3.0.  If you compiled a C++ compiler, then it should be
> possible to only type
> 
>     g++ -o a.out ......  -lsupc++
> 
> while linking.
> 
> 
> Phil
> 

Thank you, I found it out myself pretty fast !!

Small explanation.  We (from MySQL) do not like linking in any code
which has any form of C++ exceptions, as we found out too many
problems with our multi-threaded server on high load on many different
platforms. 

Therefore, I have resolved the above symbol in the manner suggested by
Nathan (thanks again). 

Then I had to resolve missing new / delete operators, which I did by
writting my own set of operators, without any use of exceptions or any
other symbol defined in libsupc++.

So far, all works just fine, thank you !!

-- 
Regards,
   __  ___     ___ ____  __
  /  |/  /_ __/ __/ __ \/ /    Mr. Sinisa Milivojevic <sinisa@mysql.com>
 / /|_/ / // /\ \/ /_/ / /__   MySQL AB, Fulltime Developer
/_/  /_/\_, /___/\___\_\___/   Larnaca, Cyprus
       <___/   www.mysql.com

Re: __cxa_pure_virtual

[Alexandre Oliva]

On Nov 30, 2001, Sinisa Milivojevic <sinisa@mysql.com> wrote:

> I guess I can find libsupc++ on ftp.gnu.org ???

It's created as part of the libstdc++ built procedure.

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

Re: __cxa_pure_virtual

[Alexandre Oliva]

On Nov 30, 2001, Sinisa Milivojevic <sinisa@mysql.com> wrote:

> I guess I can find libsupc++ on ftp.gnu.org ???

It's created as part of the libstdc++ built procedure.

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

Re: __cxa_pure_virtual

[Sinisa Milivojevic]

Alexandre Oliva writes:
> On Nov 30, 2001, Sinisa Milivojevic <sinisa@mysql.com> wrote:
> 
> > I guess I can find libsupc++ on ftp.gnu.org ???
> 
> It's created as part of the libstdc++ built procedure.
> 
> -- 
> Alexandre Oliva   Enjoy Guarana', see http://www.ic.unicamp.br/~oliva/
> Red Hat GCC Developer                  aoliva@{cygnus.com, redhat.com}
> CS PhD student at IC-Unicamp        oliva@{lsd.ic.unicamp.br, gnu.org}
> Free Software Evangelist    *Please* write to mailing lists, not to me
> 

Thank you I found it out myself pretty soon.

Small explanation.  We (from MySQL) do not like linking in any code
which has any form of C++ exceptions, as we found out too many
problems with our multi-threaded server on high load on many different
platforms. 

Therefore, I have resolved the above symbol in the manner suggested by
Nathan (thanks again). 

Then I had to resolve missing new / delete operators, which I did by
writting my own set of operators, without any use of exceptions or any
other symbol defined in libsupc++.


-- 
Regards,
   __  ___     ___ ____  __
  /  |/  /_ __/ __/ __ \/ /    Mr. Sinisa Milivojevic <sinisa@mysql.com>
 / /|_/ / // /\ \/ /_/ / /__   MySQL AB, Fulltime Developer
/_/  /_/\_, /___/\___\_\___/   Larnaca, Cyprus
       <___/   www.mysql.com

Re: __cxa_pure_virtual

[Sinisa Milivojevic]

Nathan Sidwell writes:
> 
> > Any solution or work-around ??
> You can also link with libsupc++, which contains just the C++ runtime
> support routines without the std lib stuff. Or you could define that
> symbol explicitly to the linker
> 	--defsym __cxa_pure_virtual=0
> (or, if invoked via gcc)
> 	-Wl,--defsym -Wl __cxa_pure_virtual=0
> 
> nathan
> 
> -- 
> Dr Nathan Sidwell   ::   http://www.codesourcery.com   ::   CodeSourcery LLC
>          'But that's a lie.' - 'Yes it is. What's your point?'
> nathan@codesourcery.com : http://www.cs.bris.ac.uk/~nathan/ : nathan@acm.org
> 

Thanks. Exactly what I needed. 

I guess I can find libsupc++ on ftp.gnu.org ???

I will try other recommandations too.

Thanks again.

-- 
Regards,
   __  ___     ___ ____  __
  /  |/  /_ __/ __/ __ \/ /    Mr. Sinisa Milivojevic <sinisa@mysql.com>
 / /|_/ / // /\ \/ /_/ / /__   MySQL AB, Fulltime Developer
/_/  /_/\_, /___/\___\_\___/   Larnaca, Cyprus
       <___/   www.mysql.com

Re: __cxa_pure_virtual

[Nathan Sidwell]

Sinisa Milivojevic wrote:
> Is there a way of compiling a C++ file, which does not contain any
> references to STL classes, so that resultant object file will have no
> references to the above symbol, defined in pure.cc of libstdc++.
Other than by providing definitions of all your abstract functions, no.

> Any solution or work-around ??
You can also link with libsupc++, which contains just the C++ runtime
support routines without the std lib stuff. Or you could define that
symbol explicitly to the linker
	--defsym __cxa_pure_virtual=0
(or, if invoked via gcc)
	-Wl,--defsym -Wl __cxa_pure_virtual=0

nathan

-- 
Dr Nathan Sidwell   ::   http://www.codesourcery.com   ::   CodeSourcery LLC
         'But that's a lie.' - 'Yes it is. What's your point?'
nathan@codesourcery.com : http://www.cs.bris.ac.uk/~nathan/ : nathan@acm.org

__cxa_pure_virtual

[Sinisa Milivojevic]

Hi!

Sorry for bothering you.

Please CC: a reply to me as I am not a member of the list.

Is there a way of compiling a C++ file, which does not contain any
references to STL classes, so that resultant object file will have no
references to the above symbol, defined in pure.cc of libstdc++.

This is a problem in 3.0[1,2]

I have tried using gcc for CXX, setting -fno-rtti -fno-exceptions, but
still libstdc++ has to be linked in , due to the above symbol.

Any solution or work-around ??


Many thanks in advance.

-- 
Regards,
   __  ___     ___ ____  __
  /  |/  /_ __/ __/ __ \/ /    Mr. Sinisa Milivojevic <sinisa@mysql.com>
 / /|_/ / // /\ \/ /_/ / /__   MySQL AB, Fulltime Developer
/_/  /_/\_, /___/\___\_\___/   Larnaca, Cyprus
       <___/   www.mysql.com