[Top][All Lists]
[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: problem linking with shared library
From: |
Albert Chin |
Subject: |
Re: problem linking with shared library |
Date: |
Wed, 12 Oct 2005 17:19:03 -0500 |
User-agent: |
Mutt/1.5.6i |
On Wed, Oct 12, 2005 at 01:56:39PM -0500, Nitesh Soni (NC/TNT) wrote:
> Now I dont understand one basic thing:
>
> Since both static and shared library versions of libY have this
> symbol as "U" when I link application X with static version it works
> but not with shared. Also, point to be noted is X is not using this
> symbol at all. How does shared and static libraries treat the
> symbols which are undefined.?
When you link against a static library, only those symbols required by
X are linked in.
> Thanks
>
> -----Original Message-----
> From: Albert Chin [mailto:address@hidden
> Sent: Wednesday, October 12, 2005 2:19 PM
> To: Nitesh Soni (NC/TNT)
> Cc: 'address@hidden'
> Subject: Re: problem linking with shared library
>
>
> On Wed, Oct 12, 2005 at 01:03:12PM -0500, Nitesh Soni (NC/TNT) wrote:
> > The error linker is giving is: ... libY.so: undefined reference to
> > 'Z'
> >
> > Also, this symbol is not used anywhere in any source code required
> > to build application X ( i mean if X depends on x.c y.c z.c and
> > library libY .. none of the sources x.c y.c and z.c use this symbol)
>
> That's ok. libY might be dependent on another library where Z is
> defined.
>
> > I am using gcc version 3.3.1 ( MontaVista ) building for x86.
>
> Odd that static linking works. You can extract the object files from
> libY.a to determine which one has Z undefined. As you have the source
> to libY, you can find out why the symbol is undefined.
>
> > -----Original Message-----
> > From: Albert Chin [mailto:address@hidden
> > Sent: Wednesday, October 12, 2005 1:25 PM
> > To: Nitesh Soni (NC/TNT)
> > Cc: address@hidden
> > Subject: Re: problem linking with shared library
> >
> > On Wed, Oct 12, 2005 at 11:22:42AM -0500, Nitesh Soni (NC/TNT) wrote:
> > > I am trying to build an executable "X" which links with libY.
> > >
> > > I am using libtool to build this library libY; so I have a static
> > > version libY.a and libY.so
> > >
> > > When I link the static version libY.a, i am able to build the
> > > application X But when I link against the shared version libY.so I
> > > am not able to build the application; it fails with some undefined
> > > reference to (lets say) Z
> > >
> > > Now I did "nm libY.a" and "nm libY.so"
> > >
> > > Both these versions have symbol Z as "U"
> >
> > Is symbol Z defined in executable X?
> >
> > What specific error is the linker giving?
> >
> > What platform?
> >
> > --
> > albert chin (address@hidden)
>
> --
> albert chin (address@hidden)
>
>
> _______________________________________________
> http://lists.gnu.org/mailman/listinfo/libtool
>
>
--
albert chin (address@hidden)