Re: autoconf-2.50 issues...

[Akim Demaille]

| > | Do you have some documentation describing what changed from the user point
| > | of view, between 2.13 and 2.50, a sort of "what to do when upgrading"?
| > 
| > ISTR that there is one, indeed, but maybe it's not enough.
| 
| Where can I find it?

In the doc.

Obsolete Constructs

* Obsolete config.status Use::  Different calling convention
* acconfig.h::                  Additional entries in `config.h.in'
* autoupdate Invocation::       Automatic update of `configure.ac'
* Obsolete Macros::             Backward compatibility macros
* Autoconf 1::                  Tips for upgrading your files

But I agree more would be welcome.

| I can't find it from the sources, at least. For example 
| 
| address@hidden ~/rpm/BUILD/autoconf-2.50] find -type f | xargs grep 
AC_TRY_RUN_NATIVE
| ./ChangeLog:    (AC_TRY_RUN_NATIVE): Remove.

Again, AC_TRY_RUN_NATIVE has never been public.

| ./aclang.m4:# directives must not be included.  But AC_TRY_RUN_NATIVE was not

Thanks, forgot to update this one :)


| > What did you write?  AC_LANG (2.13) and _AC_LANG (2.50) are private to
| > Autoconf.  So how come their change has influence on your code?
| 
| I don't talk about my program, I talk about "freeciv", as I said.

Sorry.

| Apparently the aclocal from freeciv is doing at a time a compare from
| AC_LANG to check which default LANGUAGE is in use.

Hm, I'll try to have a look if I have some time.

| Strange that private vars are accessible, though :-).

There is only one name space in M4.


| > That's a *warning*.  It is still tolerated.
| 
| Right - still, warnings command to correct the involved problems.

Correct.  Your (well, theirs :) use with 2.13 was incorrect.  Had
someone used --prefix-program=gnu-, it would have been installed as
gnu-gnu-.  Yes, twice.  So it is an error in 2.13, but 2.50 has magic
to avoid the problem (i.e., here you'd get gnu- anyway).

Indeed, the warning might be unneeded then.  I don't know.  What do
other people think?



| > This would be exposing yourself to future changes too.  It is not
| > defined, none of the two you are referring to are documented, and
| > therefore are not to be used by users.
| 
| So which one should I use, to fix AC_TRY_RUN_NATIVE calls?
| 
|  
| > I agree it probably means Autoconf does not provide what you need, but
| > then, you have to tell us what your needs are, *then*, we'll set up
| > the right macro, document it, and *then* guarantee some maintenance in
| > the future.
| 
| Please note I'm not a developper on this topic, I'm a "packager" whose aim
| is to make current packages build with current autoconf. (which is hard -
| FYI we've reversed to 2.13 currently)

Well, I guess it means these people should contact us, and demonstrate
their needs.  Today we use AC_RUN_IFELSE, but you don't have to know
that, the public interface is AC_TRY_RUN up to now.  Anything else is
wrong.  If this macro doesn't suit their needs, they have to tell us.

Anything which is not documented is not supported (well, roughly).