How to add a new target in binutils ?

[Shawn]

On 2012年09月21日 01:27, Ian Lance Taylor wrote:
> On Wed, Sep 19, 2012 at 11:41 PM, Shawn <shaolin.xie@ia.ac.cn> wrote:
>
>>      I'm new to binutils and I want to port a linker  to a new architecture.
>> What I need is just a very basic linker , which can link static elf object
>> files or static libraries into executables, no functionality for shared
>> library or dynamic link.
>>      I tried the Gold first,  but found it has been bounded to the binutils,
>> and can't be compiled separately. so I tried to port the bintuils as a
>> whole.
> Although gold is part of the binutils, it does not use BFD.  So to
> port gold it would suffice to just change the top level configure and
> make files.
Thanks Ian, that's great, GOLD is a nice work. I plan to take the 
gold/powerpc.cc & elfcpp/powerpc.h as my start point.

But I still have some questions. At first I have tried to compile the 
gold separately with following command :
======================================
~/Work/binutils/binutils-mpu-2.22/gold/configure 
--prefix=/home/xiesl/Tools/binutils/
make

but error occurs:
======================================
/home/xiesl/Work/binutils/binutils-mpu-2.22/gold/options.cc:35:27: fatal 
error： ../bfd/bfdver.h：no such file or directory
compilation interrupted.
make[2]: *** [options.o] error 1
make[2]:leaving `/tmp/build'
make[1]: *** [all-recursive] error 1
make[1]:leaving `/tmp/build'
make: *** [all] error 2

So can I compile the gold separately ?
>
>>     configure: error: *** unknown target vector bfd_elf32_mpu_vec
> You need to add your new vector to the list in bfd/configure.in and
> then run autoconf.
I added the bfd_elf32_mpu_vec in bfd/configure.in as follows:
======================================
....
bfd_elf32_cr16_vec) tb="$tb elf32-cr16.lo elf32.lo $elf" ;;
bfd_elf32_mpu_vec) tb="$tb elf32-mpu.lo elf32.lo $elf" ;;
....

and the run the aclocal & autoconf , but errors
======================================
xiesl@ubuntu:~/Work/binutils/binutils-mpu-2.22/bfd$ aclocal
configure.in:116: warning: macro `AM_BINUTILS_WARNINGS' not found in library
xiesl@ubuntu:~/Work/binutils/binutils-mpu-2.22/bfd$ autoconf
configure.in:116: error: possibly undefined macro: AM_BINUTILS_WARNINGS
If this token and others are legitimate, please use m4_pattern_allow.
See the Autoconf documentation.
======================================

By the way, I have used the option "--enable-maintainer-mode" at the 
first try, Will this option update the configuration script automatically ?

Shawn.