Re: make: ignore stale .depend

["Simon J. Gerraty" <sjg%crufty.net@localhost>]

On Tue, 23 Nov 2010 17:35:13 -0800, "Simon J. Gerraty" writes:
>The logic in make to ignore stale dependencies learned from .depend 
>seems incomplete.

To elaborate.  If using 'gcc -M' to capture dependencies (eg. my
autodep.mk), then .depend will include the path to the .c file as well.
Eg.

cat.o: ../../../../src/bin/cat/cat.c \
  ../../../../src/sys/sys/cdefs.h ../../../../src/sys/sys/param.h \

etc.  If the .h's move, ignoring them does little harm, but
if the .c moves, ignoring that results in the old path being fed to the
compiler, rather than searching for it via .PATH