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Multiple relocation in ELF

David Daney ddaney@avtrex.com
Tue Jul 25 00:32:00 GMT 2006 
Ian Lance Taylor wrote:
> Michael Eager <eager@eagercon.com> writes:
> 
> 
>>Can you give an example of how this might be done?  I don't think that
>>it is possible to apply two relocations to a single location in ELF.
> 
> 
> You need to write the relocation semantics so that it will work.  It
> won't work in general.
> 
> The 64-bit MIPS ABI is an example of a processor supplement which
> applies multiple relocations to a single address.  However, it does it
> in a different way, by changing the reloc format.
> 

Just a couple of days ago on gcc@gcc.gnu.org, this very point came up. 
It turns out that generating jump tables for case statements is one 
place where this could be of use.  If the jump table is in a different 
section than the code, you might need relocations to evaluate the 
distance between two symbols.

David Daney.
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