[PATCH] bfd/elf-hppa.h: Cleanup constants and comments
Nick Clifton
nickc@redhat.com
Wed Aug 22 09:34:00 GMT 2018
Hi John, Hi Helge,
> I'm think that 4 is the correct value here, because I think I read that somewhere once.
> In that case I think "2 left-shifted by this value" should show the number of bytes per table line.
> But looking at all other usages of sh_entsize, this seems unlikely and everything is still unclear.
> So, maybe we should simply leave the comment as is, until someone finds out?
FYI - the ELF spec says that the sh_entsize field is a byte quantity.
But I agree that it would be best to leave things as they are unless someone
can prove that a change is correct and does not break anything. So this is
what I have checked in:
diff --git a/bfd/elf-hppa.h b/bfd/elf-hppa.h
index 9f34a030cc..3b72140e5f 100644
--- a/bfd/elf-hppa.h
+++ b/bfd/elf-hppa.h
@@ -889,9 +889,11 @@ elf_hppa_fake_sections (bfd *abfd, Elf_Internal_Shdr *hdr, asection *sec)
asection *asec;
#if ARCH_SIZE == 64
- hdr->sh_type = SHT_LOPROC + 1;
+ hdr->sh_type = SHT_PARISC_UNWIND;
#else
- hdr->sh_type = 1;
+ /* Note - it is not clear why this is not SHT_PARISC_UNWIND as well.
+ Presumably it is a historical constraint, so leave it as it is. */
+ hdr->sh_type = SHT_PROGBITS;
#endif
/* ?!? How are unwinds supposed to work for symbols in arbitrary
sections? Or what if we have multiple .text sections in a single
@@ -912,7 +914,10 @@ elf_hppa_fake_sections (bfd *abfd, Elf_Internal_Shdr *hdr, asection *sec)
}
}
- /* I have no idea if this is really necessary or what it means. */
+ /* The unwind table entries are 16 bytes long, so it is not clear
+ why this field is set to 4. (The ELF spec says that the sh_entsize
+ field is a byte quantity, but this is a processor specific section,
+ so it is allowed to change the rules). Leave as it is for now. */
hdr->sh_entsize = 4;
}
return TRUE;
Cheers
Nick
bfd/ChangeLog
2018-08-22 Helge Deller <deller@gmx.de>
Nick Clifton <nickc@redhat.com>
* elf-hppa.h (elf_hppa_fake_sections): Use SHT_PARISC_UNWIND as
the section type of the .PARISC.unwind section on 64-bit binaries
and SHT_PROGBITS for 32-bit binaries. Add a comment about it.
Add comment about the sh_entsize value.
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