Re: Question marks in Makefile.in

[Akim Demaille]

Pavel Roskin <address@hidden> writes:

> Hello, Akim!
> 
> > > ?EXEC?insexec-data-am: install-info-am
> > > ?!EXEC?install-data-am: install-info-am
> 
> By the way, it will be nice to have a test that actually fails in absense
> of insexec-data-am or install-data-am.

Err, insexec does not exist, it should read install-exec-am.  Which is
wrong too :)

> > Still, this bug can be easily detected by automake.  But @FOO@ bugs
> 
> Maybe it's not necessary to check the output since the user is highly
> unlikely to use ?FOO? in Makefile.am. I understand it's an internal
> mechanism for Automake, not exposed to users.
> 
> However, an optional check would be appropriate. It could be turned on in
> the testsuite.

I have not understood.  Sure, this test would be enabled only for
Automake's *.am file, and only when outputting these files themselves,
not in Makefile.in.

> > are harder since we share @ with AC_SUBST.  I would really love to
> > use %FOO% instead in Automake.  Tom, what do you think?  This would
> > make it possible for automake to check what it outputs.
> 
> Are you suggesting AM_SUBST?

Nope, I'm saying it's very confusing to use @ to have automake replace
it's own automake-time variables in the *.am files, since these files
also contain AC_SUBST'd variables.  To make it more obscure, there are
even @VARS@ that can be substituted at either automake-time
substituted, or configure-time!  ISTR @AMDEP@ is one such example.
Hm...  Yep, I left a note in depend2.am:

## This file is read several times:
## - once per language for generic compilation rules
## - once for each file which requires specific flags.
##
## It is worth noting that @AMDEPBACKSLASH@ is not transformed by automake,
## it is AC_SUBST'ed, and @AMDEP@ can be both deactivated by automake,
## or by AC_SUBST.

@AMDEP@@address@hidden = @@address@hidden@
...

My suggestion is therefore that this should become

address@hidden@%FPFX%DEPMODE = @%FPFX%DEPMODE@

where ? means, automake-time Boolean, %, automake-time variable, @,
configure-time variable.

?VAR?, ?!VAR? and %VAR% are prohibited after the transform part of
file_contents.