🚀 go-pugleaf

In article <4klsr0$ii4@engnews1.Eng.Sun.COM> clamage@Eng.Sun.COM
(Steve Clamage) writes:
>In article 0804961108400001@news.aimnet.com, mike_duigou@fwb.com
>(Mike Duigou) writes:
>>One change I was hoping for was the inclusion of a non-fatal
>>"#warning" directive to match the fatal '#error" directive.  (hey,
>>the compiler can make both errors and warnings, why can't I?). As
>>you probably know, a number of compilers support the #warning
>>directive.
>
>We've been through this discussion many times. The #error directive isn't
>required to be fatal. All that is required is that it cause a message to
>be emitted. It is difficult to specify "fatal" versus "non-fatal" in a
>system-independent way.

So don't specify it.  I've seen the discussion go around a few times,
but I can't say I've ever understood the objection to requiring
#warning in the standard and letting the distinction be
implementation-defined.  The fact that there isn't a useful
distinction in some environments doesn't diminish the usefulness of a
#warning directive in the large number of environments which *do*
support such a distinction.  This wouldn't be the first item in
the standard that could be more usefully implemented in some
environments than in others.

>Adding non-standard directives like #warning is not very programmer-
>friendly.

Right; that's why it should not be non-standard.  As a non-standard
extension it's of fairly limited utility.  As a standard feature, it
would be useful in many environments, and particularly useful when
you're porting code to a new environment -- i.e., when the code you're
porting by definition can't have any compiler-specific #pragmas
available.  Its utility would lie in its portability; all compilers
would accept it, and the worst they'd do would be to behave exactly as
if they'd seen an #error.  Many compilers would do better than that.
The problem is that there is now no portable way to hint to the
compiler that it may as well go on processing after a particular
#error, even though the compiler is permitted to do so.

-David
-- 
============================================================================
David Wald      http://theory.lcs.mit.edu/~wald/     wald@theory.lcs.mit.edu
============================================================================
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