Re: RFC: Permit relative path for --with-gxx-include-dir

[Mark Mitchell <mark at codesourcery dot com>]

Daniel Jacobowitz wrote:
> On Wed, Mar 07, 2007 at 08:41:50AM -0800, Mark Mitchell wrote:
>> I'm not sure what else a relative path would be relative to, other than
>> the prefix?  The current working directory doesn't seem an obvious
>> choice to me, but that's the only other thing I can imagine.  What
>> interpretation would you make of a relative path?
> 
> "the user made a mistake" or "absolute paths don't start with / on
> this system" (which your code incorrectly assumes, by the way).

The libstdc++ Makefiles treat this path as a build-machine path (they
install files there), so I believe we can safely assume UNIX-style
paths.  (Windows users will be running from within Cygwin.)  However, if
the absolute path detection is a problem, that's certainly fixable.

The core configure-script UI design issue I was raising is that it seems
bad idea to force users to write '${prefix}' in a configure argument,
thereby depending on both an internal variable used by both configure as
well as Bourne shell syntax. That violates an abstraction barrier (by
making users refer to internal variables) and is arcane (by requiring an
obscure bit of syntax).

> Google Code Search is really handy

I don't think you said this explicitly, but perhaps your concern is
breaking existing practice?  I suppose that should have been obvious to
 me when you raised the fact that you had used the alternative syntax --
but you should never assume competence on my part!  (I thought you were
raising the point to show that people had worked out how to do the
obscure thing, not to show that my patch would break their world.)

I think that's a valid and powerful objection.  In that light, I
withdraw the patch.

Thanks,

-- 
Mark Mitchell
CodeSourcery
mark@codesourcery.com
(650) 331-3385 x713