Subject: Re: make: making .WAIT recursive
To: Manuel Bouyer <bouyer@antioche.eu.org>
From: Chuck Silvers <chuq@chuq.com>
List: tech-toolchain
Date: 02/12/2006 21:52:27
On Sun, Feb 12, 2006 at 02:43:43PM +0100, Manuel Bouyer wrote:
> In other words IMHO the problem is more in the makefiles than in
> make itself.

most of the cases where we use .WAIT today are trying to express
dependencies between things built in different directories by
separate make processes.  the makefile syntax has no way to
express such things directly, so .WAIT is the approximation
that we use instead.

this really is a lack in make itself, and I think that changing
.WAIT to apply recursively to dependencies is a better way to
satisfy the intent of our usage of it.

if we really want to fix this the best way, make would need to evaluate
the entire dependency graph of everything recursively built by the original
make invocation all at once (most likely in the same process), so that it
could consider these dependencies between directories.  then we would never
need to use .WAIT and the current issue would be moot.

-Chuck