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Re: Bootstrapping Debian GNU/Linux distribution on SuperH

>>>>> In <200109210041.f8L0fFs09672@mule.m17n.org> 
>>>>>	NIIBE Yutaka <gniibe@m17n.org> wrote:
>> Thanks for your attention.  I'd like to express my thanks to your
>> continuous efforts for Debian SuperH, too.  The (cross) bootstrap of
>> Debian SuperH is dedicated to you. :-)

 Thanks, I'll work more hardly for Debian SuperH porting ;-)

>> ISHIKAWA Mutsumi wrote:
>>  >  But ABI level incompatibility does exist between SH3 binary and SH4
>>  > binary, so binary for SH3 can not run on SH4 binary environmet.
>>  > Of cause little endien and big endian incompatibility does exists.
>> For endian, it is obvious that ABI is different.
>> For the difference between SH3 and SH4, it's somewhat complicated.  I
>> thought that SH4's ABI were backward compatible.  Actually, almost all
>> existing binaries for SH3 work fine on SH4.  You know, you can run
>> current Debian "sh-linux" on SH4.

 Yes, I know. Almost all binary-sh packages works fine on Jornada690
(SH3 machine) and Dreamcast (SH4 machine)

>> However, according to Hitachi, the ABI is different between SH3 and
>> SH4.  Please check out programming manuals of SH3 and SH4.
>> Instruction set are backward compatible.  However, some instructions
>> are allowed in delay-slot for SH3 but not for SH4.  I mean, if someone
>> tunes a program for SH3 pipeline, it may not work on SH4.  It's easy
>> to write such program, if people use assembler.  Current GCC does not
>> emit such a code (this is the reason why almost all code work fine).
>> But it's free to do so in future GCC, because the definition of ABI is
>> different.
>> SH4 kernel could emulate such cases, in theory.  We've discussed this
>> issue, but it found that it's quite hard...

 OK, I understand it.

>>  >  So, 4 separated binary arcitecture tree?
>>  > 
>>  >   binary-sh3, binary-sh4, binary-sh3eb and binary-sh4eb
>>  > 
>>  >  Is it true?
>> Exactly.

 So, We should migrate from old binary tree (binary-sh) to
new binary trees (binary-sh3, binary-sh4, binary-sh3eb and

 I want to propose the following prosess for smooth migration.

 0. Stop to working for binary-sh tree.
   (I've already stoped autobuilder for binary-sh)

 1. Please add following binaries in ftp tree and katie database,

    binary-sh3    ... Hitach SuperH SH3 little endian binaries 
    binary-sh4    ... Hitach SuperH SH4 little endian binaries
    binary-sh3eb  ... Hitach SuperH SH3 big endian binaries
    binary-sh4eb  ... Hitach SuperH SH4 big endian binaries

  Is it better that I post these change to BTS as ftp.debian.org's bug,

 2. dpkg's patch to support these architectures will be merged into
   dpkg.deb. Is this patch already uploaded to ftp.m17n.org, NIIBE ?

 3. binary-sh{3,4,3eb,4eb} build build build .... 

 4. binary-sh will be erased if it becomes at a certain time.
    I'll ask this to ftpmaster at that time.

 Almost all binary-sh packages ware built by Oliver M. Bolzer
<oliver@debian.org>, YAEGASHI Takeshi <t@keshi.org> and me.

 What do you think about this Oliver and Takeshi?

 Are any problems in this migrate process?

 <ishikawa@linux.or.jp>, <ishikawa@debian.org>, <ishikawa@redhat.com>

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