Getting host and target size and alignment information at build time?

[Daniel Jacobowitz]

On Sat, Apr 12, 2008 at 06:59:28AM +1000, Tim Josling wrote:
> > Why not get it out of GCC later?  You don't need to hack up GCC to do
> > that.
> 
> Later is too late. I need to make decisions before the GCC back end gets
> involved (the back end is in a separate OS process). For example "Is
> this literal too long for this group data item?". Or "Is a redefine
> larger than the original (which is not allowed)?". If the literal is too
> long I need to truncate it and give an error message; if a redefine is
> too large I need to extend the original and give an error message.

That's not what I meant.  You don't need it _during the GCC build
process_.  You can fork GCC and run it and have it tell you the answer
based on the current command line arguments, read its output, and
go on with what you were doing.  Which presumably involves further
compilation.

(You didn't say what you are trying to do, so I'm guessing at the
context a bit.)

-- 
Daniel Jacobowitz
CodeSourcery