Re: [PATCH]: HC11 linker relax fixes (potential pb on other relax targets)

[Alan Modra <amodra at bigpond dot net dot au>]

On Fri, Apr 04, 2003 at 11:19:41PM +0200, Stephane Carrez wrote:
>   - when we adjust the symbols after removing bytes, we must take into
>     account the symbol that marks the end of the section.  The test that 
>     exists
>     in the bfd relax targets (and that I copied!) is:
> 
>        if (isym->st_shndx == sec_shndx
>  	  && isym->st_value > addr
> 	  && isym->st_value < toaddr)
> 
>     and it is not correct if there is a section that defines a label at its 
>     very end.
>     It will not be adjusted.

I wonder why there is any test of symbol value against "toaddr"?  It
seems to me that this test is bogus, and your replacement of "< toaddr"
with "<= toaddr" just fixes one particular symbol value.  For instance,
suppose we have

 .text
 nop
 nop
sym1:
sym2 = sym1 + 2

and the relax pass decides to delete one of the nops.  Shouldn't sym2
be decremented?  Of course, you could argue that

sym3 = .text + 4

might be better left alone, but that just demonstrates the fragility
of adjusting symbols based on their value.

-- 
Alan Modra
IBM OzLabs - Linux Technology Centre