Re: i370 port - constructing compile script

["Paul Edwards" <mutazilah@gmail.com>]

Well, I have good news to report.  The restructuring was a success.

That means with those 30-odd changes to the configure scripts, I
was able to get an auto-host.h built that allowed me to take the
generated source and compile it with my own scripts as per
normal.

There's still a stack more work to do of course, such as reversing
out the ansidecl.h change, which is pretty horrible:

#ifdef PUREISO
#include "../gcc/unixio.h"
#include "../gcc/config/i370/mvspdp.h"
#endif

I needed to put in the relative path to allow compilation.

However, now I would like to know:

1. I think my unixio.h, which has a stack of POSIX functions
that need to be there (mkdir, pwait, open, fileno etc), needs to
be considered "honorary ansi" (after all, so much code assumes
that they exist) and get included in ansidecl, with unixio.h
living in include, and unixio.c living in libiberty.  Does that
sound reasonable?

2. A 3rd EBCDIC port has recently been achieved - MUSIC/SP.
As part of doing that port I ran into an old problem - IFOX's
399 external limitation.  On MVS and CMS we had people who
knew how to modify IFOX.  On MUSIC, we don't.  I have a code
workaround:

#define flag_test_coverage gflags[0]
#define flag_branch_probabilities gflags[1]
#define flag_reorder_blocks gflags[2]
#define flag_reorder_functions gflags[3]
#define flag_rename_registers gflags[4]
#define flag_force_mem gflags[5]
#define flag_force_addr gflags[6]
#define flag_defer_pop gflags[7]
#define flag_float_store gflags[8]
#define flag_strength_reduce gflags[9]

etc

What would be really good is if flags.h and toplev.c had a 
consecutive block of flags, so that even if my few lines of
intrusive code aren't accepted, it's at least easy for me to
mask out an entire block.  At the moment I have to look
for a few largish chunks of flags to mask out.

I'm not sure how many I need to mask out in total.  I'll be
experimenting with that in the coming days on one computer,
while on the other computer I will be getting the compile
scripts auto-generated from the file list.  I haven't tried
linking with the auto-generated file list yet.  I know that
it is a bit different from my list (by something like 10 files),
but haven't yet determined if it is functional anyway.

I'll come back to making the configure changes more
streamlined after the rest of the stuff is working.

BTW, with MUSIC/SP done, VSE is the only currently-used
EBCDIC programming environment without a GCC port, and
in fact, probably the only computer system (definition:
has assembler, has editor, has programmers who use that
editor, commercially-used) in existence without a free C 
compiler (and thus, to me, preventing C from being a truly
universal language for computers).  And there's only about 
1000 lines of assembler in the way of that happening.  
Unfortunately it's the same 1000 lines we've been waiting for 
several years for.  :-)  But I will be concentrating on making
the MUSIC/SP port look nicer first.  If I can get DYNALLOC
working for output datasets, it should be fine.  Otherwise,
the workaround for that problem is pretty horrible.  :-)

Anyway, thanks guys for your help.  I'll post the code after
I've cleaned it up further.

BFN.  Paul.