[Info-vax] C and C++ and clanger-free clanging (was: Re: Porting to Linux instead of x86-64 VMS, ...)

[John Reagan]

On Monday, July 8, 2019 at 2:49:07 PM UTC-4, Simon Clubley wrote:
> On 2019-07-03, John Reagan <xyzzy1959 at gmail.com> wrote:
> >
> > For the CXX DCL interface to clang++, I don't see us providing an
> > arbitrary /CLANG_OPTIONS="random string".  We'll provide a reasonable
> > mapping for the existing DCL syntax for the "recompile-and-go" crowd. 
> > We'll probably add some support for various common hardware flavors with
> > /ARCH.  Maybe a few others.  But if you want to specific lots of strange
> > exotic options, use the foreign command form.  That said, if you compile
> > without -fPIC (and perhaps a few other ones), the object probably won't
> > link/execute correctly.  In order to support shareable images,
> > INSTALL/RESIDENT, etc., you must compile with -fPIC.  The DCL interface
> > will set that for you.  We'll provide guidance when the time comes.
> 
> Please do not give in to any pressure to add an option along the lines of
> /CLANG_OPTIONS="random string" as that would cause all kinds of problems.
> For example, what happens when the manually entered options conflict with
> the options added by the other DCL qualifiers ?
> 
> I think the approach you are taking is the best of both worlds:
> 
> Ie: provide a front end driver which automatically maps the existing DCL
> language qualifiers into clang options but require the user to directly
> learn the clang options when they want to do something more complex.
> 
> They are going to have to learn something new anyway (either a newly
> made-up DCL qualifier or the appropriate clang option) so they might
> as well learn the clang option that everyone else uses instead of
> learning a VMS specific qualifier and then having to carry around
> a DCL qualifier to clang mapping table.
> 
> Simon.
> 
> -- 
> Simon Clubley, clubley at remove_me.eisner.decus.org-Earth.UFP
> Microsoft: Bringing you 1980s technology to a 21st century world

Exactly!