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Re: [committed] Return to caller when _dl_fixup fails on hppa


On 2017-07-16, at 5:31 PM, Andreas Schwab wrote:

>> That's assumed.  However, it doesn't work on hppa.  The caller has access to a non NULL pointer
>> to a function descriptor.
> 
> It works well on ia64 and ppc64, why not on hppa?

32-bit hppa doesn't have official procedure descriptors (OPDs).  Carlos at one time indicated that
he wanted to rework  binutils elf32-hppa.c to use OPDs but it never happened.  As a result, undefined
weak symbols are poorly supported.

It was a bad design and HP recognized it when they created the 64-bit hppa and ia64 runtimes.  The
32-bit hpux linker doesn't support undefined weak symbols at all.  We worked around it with one-only
support in gcc.

Anyway, one compare instruction checking the return of _dl_fixup doesn't affect performance much.
It could be removed if the problems with undefined weak functions are resolved.

Dave
--
John David Anglin	dave.anglin@bell.net




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