Re: simple autoconf question

[Nick Bowler]

On 2011-12-20 13:22 -0700, Eric Blake wrote:
> Furthermore, 'all' is a special syntactic sugar for displaying all other
> warning categories, but is not a warning category itself.  m4_warn can
> only be used with the following warning categories (at least, as of
> 2.61, which is what you are targeting as your minimum version): cross,
> obsolete, syntax

This is not what the autoconf 2.68 manual says.  Quoting §8.3.2
Diagnostic messages from M4sugar:

  — Macro: m4_warn (category, message)
  
      Report message as a warning (or as an error if requested by the
      user) if warnings of the category are turned on. If the message is
      emitted, it is prefixed with the current location, and followed by
      a call trace of all macros defined via AC_DEFUN used to get to the
      current expansion. You are encouraged to use standard categories,
      which currently include:
  
      ‘all’
          messages that don't fall into one of the following categories.
          Use of an empty category is equivalent.
      ‘cross’
          related to cross compilation issues.
      ‘obsolete’
          use of an obsolete construct.
      ‘syntax’
          dubious syntactic constructs, incorrectly ordered macro calls.

Amusingly, the statement that an empty category is equivalent turns out
to be correct (probably by accident): it fails in the same way as "all".

Cheers,
-- 
Nick Bowler, Elliptic Technologies (http://www.elliptictech.com/)