Re: (toplevel) introduce host subdir configuration in Makefile

[Nathanael Nerode <neroden@twcny.rr.com>]

>>At the moment it appears that 'gcc','zlib','fastjar', and 'libiberty' 
>>can
>>be configured in any order relative to each other (nice and 
>>straightforward).
>>If anyone knows of specific configure order dependencies, they should 
>>tell
>>me.  I'll be spending a while fiddling with gcc and src trying to 
>identify
>any other real configure order dependencies.
> Nathanael,
>
> Some heads up.
>
> GDB requires an ISO C compiler and on some systems that involves 
>running the compiler with specific flags (-Ae, I think, on HP/UX?). The 
>problem is that GDB can't test/configure this directly. By time time it 
>has a say in the matter, it is too late. The top level will need to do 
>this very early on.
This *shouldn't*, hopefully, be affected, because this doesn't require
that any other *subdirectories* be built.  The top level still 
determines the value of CC, CFLAGS, and so on and so forth, and passes 
them down to subconfigures and submakes.

> While GDB has a depencency on the SIM directory, it resolves it by 
>testing for ${srcdir)/../sim so that should be ok.
Whee.  I put a dependency in for that anyway because of the comment (in
my follow-up patch).

> While INSIGHT has a dependency on tcl/tk, it appears to resolve it 
>doing some pretty agressive hunting. It looks in both ${srcdir} and 
>`pwd`.
Extensive testing indicated that several subdirs with tcl/tk 
dependencies *did* require that in-source tcl/tk be configured; 
otherwise they used installed tcl/tk (or just failed). I dealt with this
in a subsequent patch (but I'm going to commit these patches as a whole,
probably, once I eventually get to them, since the follow-ups are 
effectively tweaks to the original).

> Andrew
Thanks for all the help.  This particular bit is likely to be the most 
destabilizing of my changes; most of the stuff prior to it was carefully
designed to be "behavior-change-free".

--Nathanael