Re: Proto patch for circular dependencies

[Pavel Roskin]

Hello, Akim!

> Index: ChangeLog
> from  Akim Demaille  <address@hidden>
>       Diagnose AC_REQUIRE circular dependencies.
> 
>       * acgeneral.m4 (_AC_DEFUN_PRO, _AC_DEFUN_EPI): Keep a stack of
>       macro expansions, _AC_EXPANSION_STACK.
>       Use `_AC_EXPANDING(FOO)' to record the fact that `FOO' is being
>       expanded.
>       (_AC_REQUIRE): Diagnose required macros which are already being
>       expanded.
>       Record in _AC_EXPANSION_STACK the AC_REQUIRE calls.
>       (_AC_EXPANSION_STACK_DUMP): New macro.

Excellent. No issues about implementation.
But please fix some typos.

> +#  2. Keeping tracking of the expansion stack

Keeping track ...

> +# 2. Keeping tracking of the expansion stack

The same.

> +# When M4 expansion goes wrong it is often extremely hard to find the
> +# path amongst macros that drove to the failure.  What is needed case

Consider removing "case"

> +# is the stack of macro `calls'. One could imagine that GNU M4 would
> +# maintain a stack of macro expansion, unfortunately it doesn't, so we

of macro expansions

> +# expansion.  Once expanded, emit it in _AC_DIVERT_DUMP.  Keep track

That's better :-)

Regards,
Pavel Roskin