[Patch,AVR]: Fix PR13697: Wrong symbols with --gc-sections

[Hans-Peter Nilsson]

On Mon, 28 May 2012, Georg-Johann Lay wrote:
> This bug is because an empty .data will be removed by the ld machinery.

I think that bug has been fixed, at least, if you add a
symbol-setting (one without PROVIDE) which seems slightly better
than decorating input .data sections with KEEP, which just stops
--gc-sections for *any* input .data.

> ld/
>     PR 13697
>     * scripttempl/avr.sc (.data): Keep it.
>

(bah, I have to cutnpaste; pine doesn't quote attachments):
>     *(.data)
>+    /* --gc-sections will delete empty .data. This leads to wrong start
>+       addresses for subsequent sections because -Tdata= from the command
>+       line will have no effect, see PR13697.  Thus, keep .data  */
>+    KEEP (*(.data))

"KEEP" is a decoration, not a separate statement.  At a minimum,
drop the first "*(.data).  It's at least confusing, but might
add a second copy, I'm not sure.  Try without --gc-sections and
gc:able .data.

Though, adding a symbol should do it, at least for a corrected
linker.

brgds, H-P