Re: autoconf 2.61: AC_DEFINE variable with parenthesis

[Paul Eggert]

>> > AC_DEFINE([DEF(x)], [somevalue])
>> 
>> Ouch!  That's not supported, and I'm surprised you got it to work as
>> well as it did.
>
> status.m4 contains a code which supports this, so until now I had no
> idea that this may be deprecated.  I think this feature was available
> since the beginning of Autoconf.

When you say "this", do you mean AC_DEFINE([DEF(x)], [somevalue]),
or do you mean merely putting something like this into config.h.in:

  #define DEF(x) somevalue

and having 'configure' ignore it if DEF is not otherwise affected by
substitutions?

> I understand that there is no real reason to use this feature, but
> OTOH, when we remove it we'll again hear cries that "the Autotools
> people are never able to produce a backward compatible release".

The old behavior was never documented, so I'm less sympathetic
to this argument than I might otherwise be.

Would you also support perverse configure.in files like this?  They
"worked' in Autoconf 2.60 but not 2.61.  (In 2.61 this test fails
miserably, at autoconf time, with a mismatched m4 macro.)

   AC_INIT([TEST], [1], [somebody])

   AC_DEFINE([DEF(x], [) x])

   AC_CONFIG_HEADER([config.h])
   AC_OUTPUT

> Shouldn't we rather maintain the feature?

If it's easy to support the particular test that started this thread,
please feel free.