Re: autoupdate: AU_ALIAS shouldn't affect itself

[Eric Gallager]

On Tue, Jan 26, 2021 at 4:00 PM Nick Bowler <nbowler@draconx.ca> wrote:

> On 2021-01-26, egall--- via Bug reports for autoconf
> <bug-autoconf@gnu.org> wrote:
> > Say I have an M4 macro file with an AU_ALIAS usage in it like this:
> >
> > AU_ALIAS([BNV_HAVE_QT], [AX_HAVE_QT])
> >
> > If I run autoupdate on this file, that will become:
> >
> > AU_ALIAS([AX_HAVE_QT], [AX_HAVE_QT])
> >
> > This seems pointless, as now the AU_ALIAS won't do what it was originally
> > meant to do anymore. Perhaps autoupdate could be updated to stop making
> > this change.
>
> It does seem counterproductive.  Unfortunately autoupdate doesn't actually
> understand m4 syntax so it often runs into problems similar this one.


Yeah, another one like this I noticed was autoupdate expanding macros in
comments,
which means I can't do things like this:

dnl Can't use AC_TYPE_SIGNAL here because it is obsolete
or
# Stop using AC_HEADER_STDC here because it is deprecated

(without escaping them, that is)

I'm sure it could be improved to better handle this specific case, though.
>
> But for the same reason, you should be able to work around the problem
> just by quoting differently, for example:
>
>   AU_ALIAS([BNV_][HAVE_QT], [AX_HAVE_QT])
>
> Cheers,
>   Nick
>