.relr.dyn, binutils 2.37 and glibc 2.36

.relr.dyn, binutils 2.37 and glibc 2.36

[Tom Kacvinsky]

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I have seen lots of stuff float by on the glibc and binutils list about
changes to each related to relocations.  My I've lost track of what
changes have been made.  I am not sure if this should be posted to
the glibc list or here, so I am trying here first instead of cross posting.

I have a colleague that is using a glibc 2.36 based system and is
using binutils 2.37 (one that I built from source, not the system ld).

This is the error he gets

/opt/binutils-2.37/bin/ld: /lib64/libc.so.6: unknown type [0x13] section
`.relr.dyn'

But then he follows up that while ld.bfd doesn't work, ld.gold (i.e.,
-fuse-ld=gold)
does work.

My recollection is that the changes made in the newer versions of glibc for
relocations required a newer binutils (2.38, I think).

So, what binutils should we be using?  And why, with 2.37, does ld.bfd
croak,
but ld.gold does not?

And yes, I know, if it is a really new system, we should be using the system
binutils for compatibility.  Doing things from source is a vestige of the
fact that
our automated build machine is ancient, so a lot of our tool chain is built
from
source.

Thanks and regards,

Tom

Re: .relr.dyn, binutils 2.37 and glibc 2.36

[Andreas Schwab]

On Sep 12 2022, Tom Kacvinsky via Binutils wrote:

> And why, with 2.37, does ld.bfd
> croak,
> but ld.gold does not?

Probably because ld.gold doesn't even look at it.

-- 
Andreas Schwab, schwab@linux-m68k.org
GPG Key fingerprint = 7578 EB47 D4E5 4D69 2510  2552 DF73 E780 A9DA AEC1
"And now for something completely different."

Re: .relr.dyn, binutils 2.37 and glibc 2.36

[Alan Modra]

On Mon, Sep 12, 2022 at 02:27:24PM -0400, Tom Kacvinsky via Binutils wrote:
> I have seen lots of stuff float by on the glibc and binutils list about
> changes to each related to relocations.  My I've lost track of what
> changes have been made.  I am not sure if this should be posted to
> the glibc list or here, so I am trying here first instead of cross posting.
> 
> I have a colleague that is using a glibc 2.36 based system and is
> using binutils 2.37 (one that I built from source, not the system ld).
> 
> This is the error he gets
> 
> /opt/binutils-2.37/bin/ld: /lib64/libc.so.6: unknown type [0x13] section
> `.relr.dyn'

For a very long time ld.bfd has rejected object files with unknown
ELF sections.  Quite possibly it would be better if ld.bfd accepted
dynamic objects with unknown section types, but that's the way it
works now.

> But then he follows up that while ld.bfd doesn't work, ld.gold (i.e.,
> -fuse-ld=gold)
> does work.
> 
> My recollection is that the changes made in the newer versions of glibc for
> relocations required a newer binutils (2.38, I think).

Yes.

-- 
Alan Modra
Australia Development Lab, IBM