Re: Putting C++ code into gcc front end

[Zack Weinberg <zack at codesourcery dot com>]

Nathanael Nerode <neroden at twcny dot rr dot com> writes:

>>Ignoring Ada for the moment, what if we only built the C front end,
>>optimizers, and back end during all three stages of a bootstrap?  And
>>then came back to build the other front ends when we were done?  At
>>that point, using C++ in the Java front end becomes substantially less
>>hassle: we just have to make sure the C++ front end and runtime
>>library are built first.  This effectively puts each front end on the
>>same footing as its runtime library.
>
> Uh.  The problem is, simply, that currently all languages are built as 
> part of 'one compiler'.  I'm not sure it's safe or easy to try to 
> decouple the middle-end/back-end build from the front end builds as much 
> as you (and Gaby) seem to be suggesting.  It may be, I'm just not sure.

I think it is easy - configure all languages, then do the equivalent
of

make all-libiberty
cd gcc
make bootstrap LANGUAGES=c  # or "c ada"
make LANGUAGES="complete list" CC="./xgcc -B./" CFLAGS="$(BOOT_CFLAGS)"
cd ..
make all

> If it isn't easy, then 'making sure the C++ front end and runtime 
> library are built first' means 'making sure a complete build is 
> done including C++ first', which means *extra stages*.  This is the 
> point I seem to have trouble getting across.

Oh, I'm quite aware for the need for extra stages if we don't do
something like the above.

zw