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[RFC] Emit OPD reloc for all global symbols and then some.

H. J. Lu hjl@lucon.org
Mon Jun 20 20:41:00 GMT 2005 
On Mon, Jun 20, 2005 at 04:26:25PM -0400, John David Anglin wrote:
> > > Under hppa-linux:
> > > ------------------
> > > We want to generate a PLABEL32 (OPD reloc) against all global symbols,
> > > and then some. For example it should be possible for an application to
> > > call dlsym asking for the address of main, and when compared to main it
> > > should match.
> > > 
> > 
> > Does it work on Linux/ia32? If not, why should it work on Linux/hppa?
> 
> The linux manpage for dlsym indicates that symbols in the main
> program can be looked up with dlsym:
> 
>      If filename is a NULL pointer, then the returned handle is
>      for the main program.  When given to dlsym(), this  handle
>      causes a search for a symbol in the main program, followed
>      by all shared libraries loaded  at  program  startup,  and
>      then all shared libraries loaded by dlopen() with the flag
>      RTLD_GLOBAL.
> 
> So, if it doesn't work, that would seem to be a bug in Linux/ia32.

It works if the global symbol is exported. But not all global symbols
in main are exported by default. You can use --export-dynamic to export
all global symbols.


H.J.
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