[v3] Abstract target specific ABI tweaks

[Benjamin Kosnik]

>2004-07-02  Paul Brook  <paul@codesourcery.com>
>
>	* configure.ac: Set ABI_TWEAKS_SRCDIR.
>	* configure.host: Set abi_tweaks_dir.  Check for atomicity.h when
>	setting atomicity_dir.  Override type_cpu for arm based targets.
>	* include/Makefile.am (host_headers): Add cxxabi_tweaks.h.
>	* libsupc++/cxxabi.h: Include bits/cxxabi.h. Don't declare __guard.
>	* libsupc++/guard.cc: Use definitions from cxxabi_tweaks.h.
>	* libsupc++/vec.cc: Ditto.
>	* config/cpu/arm/cxxabi_tweaks.h: New file.
>	* config/cpu/generic/cxxabi_tweaks.h: New file.
>	* */Makefile.in: Regenerate.
>	* configure: Regenerate.

This looks fine to me.

-benjamin