libXaw3d: optional features

[Rafał Mużyło]

On Sun, Aug 28, 2011 at 10:15:05AM -0400, Gaetan Nadon wrote:
> 
>         "AM_YFLAGS is usually used to pass the -d option to yacc. 
>         Automake knows what this means and will automatically adjust its rules
>         to update and distribute the header file built by ‘yacc -d’."
> 
>
> ./configure --help:
> 
>           YFLAGS      The list of arguments that will be passed by default to $YACC.
>                       This script will default YFLAGS to the empty string to avoid a
>                       default value of `-d' given by some make applications.
> 
> 
> It would appear there is a long story behind this. Not to mention
> platforms we don't use,
> different versions of yacc and bison, make programs, backward
> compatibility, etc..., etc...
> 
> There are a couple of apps and the xserver using it as well and I find
> it reassuring when the same situations are coded the same way and have
> been reviewed.
> 
I can't say that I've used yacc, but 'bison -y -Wall' doesn't print any
compatibility warnings about '%defines', so it should have been OK.

What I really am complaining about, is automake using *only* YFLAGS for
the detection, while '%defines' seems to be a valid solution too.