Why does "make" "order-only-prequisities" work oddly with stems ?

[Paul LAURENT]

Hi everybody,


First of all, I understood this about "order-only-prequisities" :

If a rule only depends on an order only requisities, it means that the target will only be rebuilt upon the prequisity existence condition (instead of the modified time condition)

I joined the short Makefile "order-only.mk" and a script which runs this Makefile. This should reproduce the strange behaviour I noticed.

After cutting/pasting the followings lines respectively into "
order-only.mk" and "test.sh" files, you should get the following result after running "test.sh" (be carefull that "oo-prereq" time is really newer than the target in case your system time is not accurate) :

 *** First build ***
 "Making test.out ..."
 "Making test-stem.out ..."
 *** Build after order only prerequisity is modified ***
 "Making test-stem.out ..."


As expected, the target "
test.out" is not rebuilt but "test-stem.out" is rebuilt in spite of the fact that "oo-prereq" is order only.
If you run "make" in verbose mode ("-d" option), you will notice that in the "stem" case, the order only prereq is recognized as a regular target so make rebuild the target.

=> Please tell me if I misunderstood anything ?
=> Does my "order-only.mk" contains some error ?
=> Is it a GNU make 3.80 bug ?


Thanks in advance for your help.



------------------------- order-only.mk -------------------------
all:		test.out test-stem.out

test.out:	test.in  | oo-prereq
		@echo "Making $@ ..."
		@touch $@

%-stem.out:	%-stem.in | oo-prereq
		@echo "Making $@ ..."
		@touch $@
-----------------------------------------------------------------


---------------------------- 
test.sh ----------------------------
#/bin/sh

rm -f test.in test-stem.in test.out test-stem.out

echo "*** First build ***"
touch 
test.in test-stem.in oo-prereq
make -f order-only.mk

echo "*** Build after order only prerequisity is modified ***"
touch oo-prereq
make -f order-only.mk
-----------------------------------------------------------------