Re: make: ignore stale .depend

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

Sorry forgot to address your other comment.

If the header recorded in .depend moves, 
it is going to be ignored anyway, so the fact that it gets tweaked - to
potentially help its seach, does no harm as shown below.

$ make
make: ignoring stale .depend for 
/c/sjg/work/bt/src/buildtools/tests/stale0/foo.c
make: ignoring stale .depend for 
/c/sjg/work/bt/src/buildtools/tests/stale0/foo.h
make: ignoring stale .depend for 
/c/sjg/work/bt/src/buildtools/tests/stale0/goo.c
make: ignoring stale .depend for 
/c/sjg/work/bt/src/buildtools/tests/stale0/h/goo.h
make: ignoring stale .depend for goo.h
cc -O2 -I/c/sjg/work/bt/src/buildtools/tests/stale2/h    -MD -MF goo.d -MT 
goo.o   -c /c/sjg/work/bt/src/buildtools/tests/stale2/goo.c
cc   -o stale  -Wl,-rpath,/usr/lib:/usr/lib main.o foo.o goo.o 
$ make
$ touch ../stale2/h/goo.h                                 
$ make
cc -O2 -I/c/sjg/work/bt/src/buildtools/tests/stale2/h    -MD -MF goo.d -MT 
goo.o   -c /c/sjg/work/bt/src/buildtools/tests/stale2/goo.c
cc   -o stale  -Wl,-rpath,/usr/lib:/usr/lib main.o foo.o goo.o 
$