Re: AC_CONFIG_FILES assumes that build directories have sibling in the source tree

[Alexandre Duret-Lutz]

>>> "Akim" == Akim Demaille <address@hidden> writes:

[...]

 >> I can see only two options to define @abs_srcdir@ when the
 >> source directory does not exist:

 >> 1. define @abs_srcdir@ as junk
 >> 2. compute @abs_srcdir@ without using cd

 >> I've suggested option 1 in my previous mail because that seems
 >> the easier to implement, and I can't see why one would want to
 >> use this variable when the source directory does not exist.

 Akim> So why define it at all?

For uniformity.  

 >> Not AC_SUBSTing @abs_srcdir@ in this case does not seem very
 >> sensible, because it will be impossible for tools which trace
 >> AC_SUBST to know which AC_SUBSTs are substituted and which are
 >> not.  (However if what you meant was to never AC_SUBST
 >> @abs_srcdir@, then I'm all for it.  IMHO all the abs_
 >> substitutions are evil.)

 Akim> Well, by "AC_SUSBT" I was referring to the @-substitution, but not the
 Akim> actual AC_SUBST: these magic values (srcdir, buliddir, etc.)  that
 Akim> change across directories require another mechanism that AC_SUBST.
 Akim> You won't see them in AC_SUBST traces.

Point taken.

 Akim> I'm not sure which I like most currently.  As Paul, I was
 Akim> in favor of (3), but now, I'm not so sure :(

Actually Paul's patch seems the best solution to me.  IFAICT
what he calls (3) is what I call 2: the semantic of @srcdir@ and
@abs_srcdir@ isn't changed.
-- 
Alexandre Duret-Lutz