Re: [U-Boot] [PATCH] PowerPC: Change -fpic flag to -fPIC flag in the config.mk

26 Apr 2012


      On 04/26/2012 01:53 AM, Joakim Tjernlund wrote:
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Scott Wood scottwood@freescale.com wrote on 2012/04/25 21:01:00:
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On 04/18/2012 05:07 AM, Joakim Tjernlund wrote:
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Your linker file is buggy I think. I found u-boot-nand_spl.lds, is that the one?
That's the one for the SPL part.
OK, good.
...
...
Check out that files reloc part:
.reloc : {
      _GOT2_TABLE_ = .;
      KEEP(*(.got2))
      _FIXUP_TABLE_ = .;
      KEEP(*(.fixup))
   }
   __got2_entries = (_FIXUP_TABLE_ - _GOT2_TABLE_) >> 2;
   __fixup_entries = (. - _FIXUP_TABLE_) >> 2;
Compare that with(from u-boot.lds):
 .reloc   :
  {
    _GOT2_TABLE_ = .;
    KEEP(*(.got2))
    KEEP(*(.got))
    PROVIDE(_GLOBAL_OFFSET_TABLE_ = . + 4);
    _FIXUP_TABLE_ = .;
    KEEP(*(.fixup))
  }
  __got2_entries = ((_GLOBAL_OFFSET_TABLE_ - _GOT2_TABLE_) >> 2) - 1;
  __fixup_entries = (. - _FIXUP_TABLE_) >> 2;
I notice a difference between u-boot.lds and u-boot-nand.lds -- the
latter (used for the main part of U-Boot when loaded from SPL) has:
...
.reloc   :
  {
    KEEP(*(.got))
    _GOT2_TABLE_ = .;
    KEEP(*(.got2))
    _FIXUP_TABLE_ = .;
    KEEP(*(.fixup))
  }
  __got2_entries = (_FIXUP_TABLE_ - _GOT2_TABLE_) >> 2;
  __fixup_entries = (. - _FIXUP_TABLE_) >> 2;
Is this wrong as well?
Yes, I think so.  This one does not care about the .got entries at all so I suspect
never gcc's wont work.
Thanks.
I'm not entirely sure about the _GLOBAL_OFFSET_TABLE_ stuff, though --
what's wrong with the simpler version that uses _FIXUP_TABLE_?
-Scott