Build change from 3.14 to 3.15

[<michael.abbott@diamond.ac.uk>]

I have a makefile rule in my IOC to build a .db file from a Python script, but something has changed in EPICS 3.15 (and subsequently, I guess) to break my build.  If anyone can let me know what I need to change to fix this I'd be very grateful.
 
Here is the Makefile used to generate the .db file:


TOP = ..
include $(TOP)/configure/CONFIG

DB += test.db

include $(TOP)/configure/RULES

$(COMMON_DIR)/%.db: ../%.py
	$(PYTHON) $< >$@


When run under 3.14 this runs test.py, places the output in O.Common/test.db, and places O.Common/test.db in $(TOP)/db/test.db, as expected.

When run under 3.15 it fails at the install step:


$ make
perl -CSD /scratch/epics/base-3.15.4/bin/linux-x86_64/makeMakefile.pl O.linux-x86_64 ../..
mkdir O.Common
make -C O.linux-x86_64 -f ../Makefile TOP=../.. \
	    T_A=linux-x86_64 install
make[1]: Entering directory `/home/mga83/test/epics/basic_ioc/Db/O.linux-x86_64'
python ../test.py >../O.Common/test.db
Installing created db file ../../db/test.db
make[1]: *** No rule to make target `test.db.d', needed by `build'.  Stop.
make[1]: Leaving directory `/home/mga83/test/epics/basic_ioc/Db/O.linux-x86_64'
make: *** [install.linux-x86_64] Error 2
$


In case the problem is something to do with other files I haven't show here, I've attached a complete minimal IOC.

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Attachment: basic_ioc.tgz
Description: basic_ioc.tgz