automake reports .lo file created with and without libtool

[Skip Montanaro]

I just installed autoconf 2.53 and as a result wound up installing the
Release-1-6 snapshot from the automake CVS tree.  Automake now complains:

    automake: src/Makefile.am: object `alf.lo' created both with libtool and 
without

The relevant Makefile.am file is 

    lib_LIBRARIES = libalf.a
    libalf_a_SOURCES = alf.c alf.h common.h

    lib_LTLIBRARIES = libalf.la
    libalf_la_SOURCES = alf.c alf.h common.h

    libalf_la_LDFLAGS = -version-info @ALF_LT_VERSION@

Since all references to alf.lo are implicit, it's not obvious to me where
I'm supposed to fix this problem, or if it's a problem at all.  I didn't
encounter any errors during the subsequent configure and make steps or when
running a simple test program.

Thanks,

-- 
Skip Montanaro (address@hidden - http://www.mojam.com/)