How to build a bare GNAT compiler?

["Luke A. Guest" <laguest@n_o_p_o_r_k_a_n_d_h_a_m.abyss2.demon.co.uk>]

Hi,

I want to try building a kernel image in Ada for MIPS-ELF. I can build a
C/C++ compiler and just not use the runtime libraries, but not for Ada.
What exactly do I have to do to achieve this?

I currently have the latest gcc-3.3.2 (core, g++, objc & Ada) built. For
GNAT, there exists only mips-elf-gnatbind & gnat1, no other cross binaries
get build because it wants the RTS built before the tools can be built.

So, if I try to build an empty Ada program, I get the following error:

laguest@rogue ada-test $ mips-elf-gcc -c -v empty.adb
Reading specs from /home/laguest/opt/xgcc-mips-elf/lib/gcc-lib/mips-elf/3.3.2/specs
Configured with: ../gcc-3.3.2/configure --prefix=/home/laguest/opt/xgcc-mips-elf --target=mips-elf --disable-nls --with-gnu-as --with-gnu-ld
Thread model: single
gcc version 3.3.2
 /home/laguest/opt/xgcc-mips-elf/lib/gcc-lib/mips-elf/3.3.2/gnat1 -quiet -dumpbase empty.adb empty.adb -o /tmp/cc1YjQUf.s
fatal error, run-time library not installed correctly
cannot locate file system.ads
compilation abandoned

This *must* be possible? Does anyone have a clue as to how to do it?

Thanks,
Luke.