source file in different directory to Makefile and subdir-objects

[Adam Mercer]

Hi

Since updating to automake-1.14 I'm getting warnings of the form:

src/inspiral/posterior/mpi/Makefile.am:14: warning: source file
'$(srcdir)/../LALInferenceMCMC.c' is in a subdirectory,
src/inspiral/posterior/mpi/Makefile.am:14: but option 'subdir-objects'
is disabled
automake: warning: possible forward-incompatibility.
automake: At least a source file is in a subdirectory, but the 'subdir-objects'
automake: automake option hasn't been enabled.  For now, the
corresponding output
automake: object file(s) will be placed in the top-level directory.  However,
automake: this behaviour will change in future Automake versions: they will
automake: unconditionally cause object files to be placed in the same
subdirectory
automake: of the corresponding sources.
automake: You are advised to start using 'subdir-objects' option throughout your
automake: project, to avoid future incompatibilities.

The Makefile.am in question is (stripping out some stuff to make this clearer):

CC = $(MPICC)
LIBS += $(MPILIBS)

lalinference_mcmc_SOURCES = \
$(srcdir)/../LALInferenceMCMC.c \
$(srcdir)/../LALInferenceMCMCSampler.c \
$(srcdir)/../LALInferenceMCMCSampler.h

bin_PROGRAMS = lalinference_mcmc

This code uses the source files from the parent directory but compiles
them with the MPI C compiler instead of the normal compiler.

The warning above is recommending to set the "subdir-objects" option
but I don't think this is appropriate in this case as we want objects
to be created in the directory that contains the Makefile, not the
source files.

Is there a way to silence this warning?

Cheers

Adam