[AC21.5R21.4] etags and implicit tags

[Francesco Potorti`]

> > I would prefer avoiding this, if possible, by defining VERSION in the
> > Makefile as appropriate.
>
>That makes sense.  

Good:-)

>This is not entirely trivial, as VERSION is computed in our Makefile as
>
>version=@version@
>
>and that of course is done by configure.  But it shouldn't be too hard.

You could just change the call in the Makefile where etags is built by
adding -DVERSION=whatever.  WOuldn't that be simple enough?

> > >-# if PRINT_UNDOCUMENTED_OPTIONS_HELP
> > >+# ifdef PRINT_UNDOCUMENTED_OPTIONS_HELP
> > 
> > You changed this to quench a warning, as I understand.  However, I do
> > not get any, using gcc 4.1.2 with -pedantic and -Wall.  What compiler do
> > you use?
>
>I suppose it's the -Wundef.  

I see.  In the cpp-4.1 manual I read:

   * Identifiers that are not macros, which are all considered to be the
     number zero.  This allows you to write `#if MACRO' instead of
     `#ifdef MACRO', if you know that MACRO, when defined, will always
     have a nonzero value.  Function-like macros used without their
     function call parentheses are also treated as zero.

     In some contexts this shortcut is undesirable.  The `-Wundef'
     option causes GCC to warn whenever it encounters an identifier
     which is not a macro in an `#if'.

I have added something like this:

#ifndef PRINT_UNDOCUMENTED_OPTIONS_HELP
#  define PRINT_UNDOCUMENTED_OPTIONS_HELP FALSE
#endif

I suggest you add this to etags.c if you are in a hurry to release.  I
should soon send out a new release with this change.