Re: ld fails to relocate relative to local symbols?

[Paul Lalonde <plalonde at neoptica dot com>]

I've just filed a bug, but for anyone who's keen on finding out how I  
broke it, here's a tgz containing two .o's for AMD64.
ld -r success.o succeeds, ld -r fail.o fails.  The files differ in  
exactly one byte, the change of symbol "mystring" from STB_GLOBAL to  
STB_LOCAL.
It's most likely that I'm violating the ABI in some (not necessarily  
subtle) way, although the seg fault is disconcerting.

Paul

Attachment: ldbug.tgz
Description: Binary data

On 31-Jan-06, at 6:02 PM, Daniel Jacobowitz wrote:

> On Tue, Jan 31, 2006 at 04:18:53PM -0800, Paul Lalonde wrote:
> > -----BEGIN PGP SIGNED MESSAGE-----
> > Hash: SHA1
> >
> > I have an application that uses ELF to encode it's binary data (for
> > assorted reasons, the binary data need relocation and linkage - ELF
> > already supports this well and has many tools).
> > In the process of emitting the data, it's frequently useful to
> > relocate against a local symbol (yes, I know I could add them to a
> > dictionary and do a second pass on my data to resolve them myself).
> > However, if I add a local symbol to the symbol table, and then  a
> > relocation relative to it ld seg faults when I try to link it.  If I
> > change it to a global symbol all is well. (ld -r test.o seg faults as
> > well)
> > Is is the expected behaviour (well, not the seg fault, but at least
> > not handling relocation relative to a local symbol)?
>
> Of course not.  You need to be more specific - preferably with a  
> small,
> reproducible test case.
>
> --
> Daniel Jacobowitz
> CodeSourcery