Re: avr32 build failures in linux-next

[Guenter Roeck]

On 02/06/2016 06:01 AM, Måns Rullgård wrote:
> Hans-Christian Noren Egtvedt <egtvedt@xxxxxxxxxxxx> writes:
>
> > > > Example for avr32:defconfig:
> > > >
> > > > fs/built-in.o: In function `anon_inode_getfile':
> > > > (.text+0x2ae90): relocation truncated to fit: R_AVR32_21S against
> > > > `.text'+296c0
> > > >
> > > > All builds but avr32:allnoconfig fail with such truncated relocations.
> >
> > Weirdly I do not get this when I build torvalds/master with allnoconfig.
> >
> > The avr32 kernel was never very fond of CONFIG_CC_OPTIMIZE_FOR_SIZE=n, it
> > was always built with CONFIG_CC_OPTIMIZE_FOR_SIZE=y for actual usage.
>
> 4.5-rc1 builds and runs with CONFIG_CC_OPTIMIZE_FOR_SIZE=n here.  It's a
> fairly minimal config though.

4.5-rcX is not the problem. I was talking about linux-next.

Disabling CONFIG_CC_OPTIMIZE_FOR_SIZE does not make a difference. Same problem.

> > > > Toolchain used is the old gcc 4.2.4 toolchain from kernel.org. I have been
> > > > unable to find or build newer versions of gcc for avr32.
> > > >
> > > > Does anyone know if a more recent toolchain for avr32 is available ?
> > >
> > > https://sourceware.org/ml/crossgcc/2015-10/msg00050.html
> > > says avr32 has been depreciated.
> >
> > Last release of avr32-linux GCC was the 4.2.4 patches in Buildroot for AVR32.
> >
> > Atmel never upstreamed the AVR32 patches for GCC.
>
> There are patches for gcc 4.4.3 at
> http://distribute.atmel.no/tools/opensource/avr32-gcc/
> The patches apply with only trivial fixes to 4.4.7 as well.  I tried
> forward-porting to something newer, but my knowledge gcc internal voodoo
> wasn't sufficient.
I managed to build avr32 gcc 4.4.7 from
http://distribute.atmel.no/tools/opensource/Atmel-AVR32-GNU-Toolchain/3.4.3/
after making a couple of changes in the gcc source to make its first stage build
with a recent version of gcc (looks like one can not build gcc 4.4.7 with gcc 5.2
without fixing it up first ;-).

No difference. If anything, the situation is worse, since it produces lots of

avr32-ld:built in linker script:15: warning: memory region `FLASH' not declared
avr32-ld:built in linker script:140: warning: memory region `CPUSRAM' not declared

in addition to the final 'relocation truncated to fit' error.

Since the message is produced by the linker, maybe this isn't even a compiler
problem but a problem with binutils.

> > > > Another question is if the avr32 kernel still supported, or if I should
> > > > just stop trying to build test it. Any thoughts ?
> > >
> > > I have already stopped building it.
> >
> > I build the kernel and try to fix small issues here and there.
>
> Even when it builds, it often doesn't work since non-DT support has
> bitrotted in many drivers.
Not very encouraging.

I'll stop building it after avr32:defconfig fails to build in mainline.

Guenter