Re: HPUX and +DAportable

[Bob Proulx]

Paul Eggert wrote:
> Joe Buehler writes:
> > I have a mix of PA-RISC 1.1 and 2.0 processors and am continually having
> > to manually add +DAportable to compile flags in order to get binaries to
> > run on both kinds of machines (since I compile on a PA-RISC 2.0 machine).
> > 
> > Is there some reason this is not currently added by autoconf?
> 
> I don't think anyone has ever raised the issue before.

I have vague memories of something several years ago.  But it is the
vendor's choice to default to the native system optimization.  I think
the user in this case would need to say more to get different
behavior.  And I think that is the right answer.

Remember that by compiling for the other architecture you are
effectively operating in a cross compilation mode.  It is a simple
crosscompile in this case but still not the native mode.  The
autotools support a large amount of cross compilation.  But that is
not the default behavior.  The default is to compile for the native
environment.  I think that still makes the most sense.

I also have a large mixed environment of HP-UX hardware.  Except I
have pretty much replaced PA1.1 in favor of PA2.0.  My last remaining
80 MHz PA1.1 9000/712 just can't compete with modern machines.  :-)

So as one of the other people who has been affected by this for years
I would still vote to keep autconf ignorant of DAportable.  Using it
would needlessly slow down users on systems which do not need
compatibility to older architectures.  It would force those users to
supply a configuration to compile for the native architecture in order
to gain back the performance.  And there are available other methods
of solving this problem which work equally well so it is unneeded.

> Generally Autoconf defers to the compiler-supplier and/or the
> installer on issues like these.  Perhaps the simplest thing is for you
> to add a simple shell-script wrapper that always passes +DAportable to
> your compiler.

Ralph suggested the use of 'CCOPTS' and 'LDOPTS' which are effectively
global variables to the compiler and linker which pass extra options
to them on HP-UX.  The autotools don't know about them so they will
cut through all layers completely transparently.  This is what I do
in my environment too.  It works well for me.

Bob