Re: [avr-gcc-list] Re: Removal of unused functions

[Joerg Wunsch]

Bernd Trog <address@hidden> wrote:

> IMO, we should clearly distinguish between compile-time and link-time
> optimizations:

> compile-time: (gcc-4.1+)

> Use __attribute__((used)) for ISRs if you call gcc with -combine
> -fwhole-program *.c.

OK, that'll require changes in avr-libc (in the prototype for ISR()).
Should be easy though.

Are there any other changes required?

> link-time: (binutils ~2.10+)

> Use KEEP(vectors) in the linker script if you call ld with
> --gc-sections.

Ah OK, that's the other thing I was curious about, and I see it's
present in current binutils.  Can anyone tell whether it's already
present in binutils-2.17?

-- 
cheers, J"org               .-.-.   --... ...--   -.. .  DL8DTL

http://www.sax.de/~joerg/                        NIC: JW11-RIPE
Never trust an operating system you don't have sources for. ;-)