Re: AIX and shared libraries (missing vtable)

Re: AIX and shared libraries (missing vtable)

[David Edelsohn]

	AIX ld -bexpall does not export symbols with a prepended
underscore, as is specified by GCC C++ ABI.  One needs to explicitly
generate an export symbol list.

David

Re: AIX and shared libraries (missing vtable)

[Alexandre Oliva]

On Jun  3, 2003, Eljay Love-Jensen <eljay@adobe.com> wrote:

> It's probably having a problem with your non-standard ".o" extension
> on the shared-library you've produced called "shr.o", and then
> packaging that shared-library into an archive library (.a).  Very
> unusual.

Not unusual at all if you're familiar with the several different
flavors of shared libraries supported by AIX.  This happens to be
exactly the right way to create one of such flavors.

-- 
Alexandre Oliva   Enjoy Guarana', see http://www.ic.unicamp.br/~oliva/
Red Hat GCC Developer                 aoliva@{redhat.com, gcc.gnu.org}
CS PhD student at IC-Unicamp        oliva@{lsd.ic.unicamp.br, gnu.org}
Free Software Evangelist                Professional serial bug killer

Re: AIX and shared libraries (missing vtable)

[Eljay Love-Jensen]

Hi Joerg,

It's probably having a problem with your non-standard ".o" extension on the 
shared-library you've produced called "shr.o", and then packaging that 
shared-library into an archive library (.a).  Very unusual.

Sincerely,
--Eljay

AIX and shared libraries (missing vtable)

[Joerg.Richter]

Hi,

I have problems building shared libraries on AIX. 

$ g++ -v
Reading specs from
/tools/pkg/gcc/3.2.1/lib/gcc-lib/powerpc-ibm-aix5.1.0.0/3.2.1/specs
Configured with: configure --prefix=/tools/pkg/gcc/3.2.1 --with-ld=/bin/ld
--with-as=/bin/as --enable-languages=c,c++
Thread model: aix
gcc version 3.2.1

I have following reduced testcase:

----- sh.h -----
struct A
{
    virtual ~A();
};

----- sh.cc -----
#include "sh.h"

A::~A()
{}

----- main.cc -----
#include "sh.h"

int main()
{
  A a;
  return 0;
}

----- buildscript -----
CC="/tools/pkg/gcc/3.2.1/bin/g++"

$CC -c -o sh.o sh.cc
$CC -shared -Wl,-bexpall -o shr.o sh.o
ar cruv libsh.a shr.o
ranlib libsh.a
$CC -c -o main.o main.cc
$CC -o main main.o -L. -lsh

The last command has this error messages:

ld: 0711-317 ERROR: Undefined symbol: vtable for A
ld: 0711-345 Use the -bloadmap or -bnoquiet option to obtain more
information.
collect2: ld returned 8 exit status


The best is, that nm on the library says, that the vtable for A is in the
library

dump -Tv says that the symbol for the vtable is not in the export list of
the library. But -bexpall should have made this. I know that this is a
aix-ld option, but perhabs there is any option for g++ that i have overseen?

Can someone please help me figure out what goes wrong?

tia

Joerg Richter