Re: microblaze port committed

[Isaac Dunham <idunham@lavabit.com>]

On Sat, 29 Sep 2012 01:41:57 -0400
Rich Felker <dalias@aerifal.cx> wrote:

> Hi all,
> 
> I've committed the initial (and seemingly fully-working) version of
> the microblaze port. Several caveats:
> 
> 1. Upstream binutils has a serious bug in gas whereby the relocations
>    it generates for symbols with local weak definitions cannot be
>    resolved by the linker. Patch at:
>    http://permalink.gmane.org/gmane.linux.uclinux.microblaze/11155
> 
> 2. The toolchain binaries from Xilinx seem to produce .o files
>    incompatible with standard binutils, and vice versa. Pick one or
>    the other; don't mix them.
For Landley's sake, I'll mention what we discussed on IRC (+ some details):
-The Xilinx toolchain is binutils 2.16 + gcc 4.1.2 (GPLv2); binutils support was merged upstream in 2009, so Aboriginal would need the Xilinx EDK toolchain (see http://git.xilinx.com/?p=mb_gnu.git;a=summary ofor source)

-Rich says that on microblaze, due to the way relocations are handled, using -Bsymbolic instead of -Bsymbolic-functions gives a libc.so that is either minimally broken or fully operational.
(Mips also works with -Bsymbolic.)

-The possibility of using mapfiles instead of -Bsymbolic-functions was mentioned, but Rich doubts that they were supported in older binutils.
 
> 3. Threads are untested because qemu is broken, at least my version of
>    qemu (app-level emu) has a bug where clone() does not advance the
>    program counter properly in the child, so it starts a forkbomb-like
>    cascade of clone syscalls (thankfully just linear growth rather
>    than exponential).
Ow.

Rob, any thoughts on an Aboriginal port?

-- 
Isaac Dunham <idunham@lavabit.com>