Re: quoting bug in definition of AC_DEFINE and AC_DEFINE_UNQUOTED

[Eric Blake]

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According to Bruno Haible on 6/1/2009 4:07 AM:
> Hi,
> 
> The first argument passed to AC_DEFINE or AC_DEFINE_UNQUOTED is subject
> to m4 macro expansion.

My feeling is that it should be, for consistency with most other
single-quoted arguments.

> 
> So it appears that the unexpanded argument is put into config.h.in

Thus, that looks like a bug in autoheader.

> but
>   1) the expanded argument is used in confdefs.h at configure time,
>   2) the expanded argument is used in config.status (which has no
>      effect because the config.h.in contains the unexpanded argument).

The fact that it has no effect is a knock-on effect that autoheader didn't
put the right thing in config.h.in in the first place.

> Should the unexpanded argument be used everywhere, or should the expanded
> argument be used everywhere?
> 
> This is a long-standing bug. It exists at least since autoconf 2.53.

Thanks for the report.  I'll see if I can find a way to make autoheader
also do the expansion (it tends to be more simplistic in how it parses,
because it is intentionally bypassing a lot of autoconf's complexities).

- --
Don't work too hard, make some time for fun as well!

Eric Blake             address@hidden
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