Alignment of .rodata symbols wasting space

[Ishwar Rattan]

If I recall correctly the data has to be properly aligned
for correct access under SPARC else you might see bus-error
run time errors..

-ishwar


On Fri, 13 May 2005, John Carter wrote:

> I am linking an executable for an embedded target with very limited
> rom/ram resources.
>
> While analysing our space requirements I noted a fairly large discrepancy
> between the amount of rodata reported by readelf vs adding up the
> individual symbols reported by objdump --syms. (About a factor 1.5)
>
> As far as I can see, there are two sources for this discrepancy...
>    1) Alignment. (1 byte symbol followed by a 4 byte aligned symbol)
>    2) Some large mysterious other thing between the last symbol and the end
>       of the rodata segment..
>
> Question 1)
>   Any ld flags / linking script options / ... that I can use to pack all
>   byte aligned objects together?
>
> Question 2)
>   Any guesses as to what are the mystery rodata items that are not showing
>   up in objdump --syms?
>
> Question 3)
>    Are these problems perhaps an artifact of the somewhat elderly version
>    of the toolchain we are using? ie. Would upgrading solve this problem?
>    sparc-rtems-gcc 2.95.2
>    sparc-rtems-objdump 2.11
>
>
> Thanks,
>
>
> John Carter                             Phone : (64)(3) 358 6639
> Tait Electronics                        Fax   : (64)(3) 359 4632
> PO Box 1645 Christchurch                Email : john.carter@tait.co.nz
> New Zealand
>
>