Re: --with-foo= vs. FOO=${FOO:-foo_default}

[Troy Cauble]

> Philip Willoughby wrote, on  Mon, 2 Sep 2002 14:56:39 +0100 (BST)

> Today, address@hidden wrote:
>
> > > It may be wrong (or merely suboptimal) to abuse --with and --enable, but if
> > > the only tool you have is a hammer...
> >
> > This is unfortunately how I feel.  I hate to abuse the --with flags, but
> > setting 27 different environment variables or editing a config file feels
> > like a step back.
>
> Blindingly obvious answer:
>
> Why not copy the AC_ARG_WITH macro and rename it to AC_ARG_DEFAULT and
> change the code appropriately.
>
> It seems sensible to me to change the defaults at configure time, but I
> agree then --with and --enable are inappropriate.

A related question:

I'm porting a large, full-featured, autoconf-based project to an embedded linux
system where certain features cannot be supported.  The C/C++ files will
require a -D flag to control some ifdefs.  The Makefile.am's will require
either ifeq statements or @MY_FLAGS@ style substitutions.

Is the best way to trigger all this with --with, --enable, or something else?

Thanks,
-troy