GCC Needs a backend cleanup and complete rewrite

[Geert Bosch]

On Thu, 22 Feb 2001, Marc Espie wrote:
|In fact, if gcc was no longer written in C and required a cross-compiler
|for the initial bootstrap, this might also help cleaning up some rather
|arcane issues with cross-compiling...
|
|A joke ? not completely, think about it...

GNAT, the GNU Ada front-end for GCC, has always been written in
Ada. After the first bootstrap, for which a commercial Ada83 compiler
was used, all builds and ports have been done using GNAT itself.

Although we have thought many times about schemes to be able
to bootstrap from a system compiler, it turned out that in
practise there were very few problems doing cross-compiles,
or bootstrapping from a previous version. (We always guarantee
that version X can bootstrap version X+1.)

It makes sense to implement a compiler for a general-purpose
language X in X, as that will often be the language the developers 
know and like best. Furthermore bootstrapping the compiler becomes
more meaningful and is an easy sanity check to verify correct
compilation and spot performance issues.

  -Geert