[PATCH] S/390: Fix two issues with the IFUNC optimized mem* routines

[H.J. Lu]

On Sat, Sep 1, 2012 at 2:24 PM, Richard Henderson <rth@twiddle.net> wrote:
> On 2012-09-01 10:21, H.J. Lu wrote:
>> It may work for other targets.  But x86 doesn't have a relax
>> pass.  I believe doing it in size_dynamic_sections is more
>> sensible.
>
> It *should* have a relax pass.  Especially as that allows one

A relax pass won't work properly for x86 without some surgery
since lang_relax_sections is called after bfd_elf_size_dynamic_sections
which calls elf_x86_64_allocate_dynrelocs to allocate GOT entries
and dynamic relocations. After it is done, it is not to easy to undo
the damage.

> to turn it all off just in case a bug is encountered.
>

This is a separate issue.  X86 backends also optimize
TLS relocations.  Some compilers generate bad TLS
sequences which lead to corrupted output:

http://sourceware.org/bugzilla/show_bug.cgi?id=4928

But there is no way to turn off the TLS optimization.  It
will be nice to move disable_target_specific_optimizations
from command_line to link_info so that a backend
can check it.


-- 
H.J.