parents would be get remade, even if children were not really updated
by the commands executed for them. It also makes all the children have
the real modification time set if possible, so it should fix some other
timing weirdnesses...
- collapse childMade and make fields into flags and convert them to bits
CHILDMADE and REMAKE
- introduce FORCE flag that gets set in all the parents of a child that
has no sources and does not exist.
- set oodate if the FORCE flag is set, and not if CHILDMADE
- centralize the RECHECK into Make_Recheck() and use this in make.c and compat.c
- use Make_TimeStamp for all child -> parent timestamp propagations
Make used to only use the search path for nodes that were pure
sources (not targets of other sources). This has been corrected
and now gnu-autoconf generated Makefiles work in directories other
than the source one.
- Suffix transformation rescanning:
Suffix transformations (.c.o:; cc ...) were only recognized in
the past when both suffixes were members of the suffix list.
Thus a sequence like:
.z.b:
echo ${.TARGET}
.SUFFIXES: .z
would cause .z.b: to be inserted as a regular target (and the main
target in this case). Other make programs always add rules that
start with a period in the transformation list and never consider
them as targets. We cannot do that (consider .depend files) so we
resort to scanning the list of the current targets every time a
suffix gets added, and we mutate existing targets that are now
valid transformation rules into transformation rules. If the
transformed target was also the main target, we set the main target
to be the next target in the targets list.
1. ${.*} variables did not get expanded in dependencies.
2. expanded ${.*} variables in .USE dependencies can cause tree
restructuring; handle it.
3. in compat mode, expand .USE before evaluating the list of targets,
instead of doing .USE expansions on demand, because they can cause
tree restructuring.
