Using convenience libraries with non-recursive make

[Del Merritt]

I'm using automake 1.11.1 and autoconf 2.68.  I am switching from a set 
of hand-written Makefiles to autoconf/automake.  I'm switching to 
autotools since the support for cross-compilation is already there; my 
hand-written Makefiles are getting hard to manage, and they don't 
support VPATH builds cleanly.

I have a lot of source files (4K+) and a lot of libraries (40+).  My 
goal is to generate a single (typically/initially static) library and an 
executable that demos/drives it.  I am hoping to avoid a recursive make 
(SUBDIRS=...), since I am holding to the "Recursive makefiles considered 
harmful" mantra.

A representative Makefile.am for my project is:

   # Automake rules to build application.
   AM_CXXFLAGS = -I${includedir}
   ACLOCAL_AMFLAGS = -I m4
   bin_PROGRAMS = myprog
   myprog_SOURCES = b/c/d/myprog__main.cpp
   myprog_LDADD = libmyprog.la
   lib_LTLIBRARIES = libmyprog.la
   nodist_EXTRA_libmyprog_la_SOURCES = dummy.cxx

   lib_LTLIBRARIES += liba_s1.la libb_s2.la libb_c_s3.la libb_c_d_myprog.la

   libmyprog_la_LIBADD =  liba_s1.la libb_s2.la libb_c_s3.la
   libb_c_d_myprog.la
   liba_s1_la_SOURCES = a/s1.cpp
   libb_s2_la_SOURCES = b/s2.cpp
   libb_c_s3_la_SOURCES = b/c/s3.cpp
   libb_c_d_myprog_la_SOURCES = b/c/d/myprog.cpp

And it's similarly-simple configure.ac:

   AC_PREREQ([2.59])
   AC_INIT([libmyprog], [1.0], address@hidden)
   AM_INIT_AUTOMAKE([foreign subdir-objects])
   AC_CONFIG_SRCDIR([a/s1.cpp])
   AC_CONFIG_HEADERS([libmyprogconfig.h])
   AC_CONFIG_MACRO_DIR([m4])
   AC_PROG_MKDIR_P
   AC_PROG_CXX
   AM_PROG_LIBTOOL
   AC_CONFIG_FILES([Makefile])
   AC_OUTPUT

The directory structure is similar to:

   ./a/s1.cpp
   ./b/s2.cpp
   ./b/c/d/myprog.cpp
   ./b/c/d/myprog__main.cpp
   ./b/c/s3.cpp

and in my real project there's lots more source in each subdirectory, 
and lots more nested subdirectories.  Yes, the source containing main() 
is down deep in the structure; myprog.cpp instances some top-level 
classes, and myprog_main.cpp is just the main() that gets things rolling.

When ./configure and make, I get:

   address@hidden ~/am $ make
   make  all-am
   make[1]: Entering directory `/home/del/am'
   make[1]: *** No rule to make target `libmyprog.lo', needed by
   `libmyprog.la'.  Stop.
   make[1]: Leaving directory `/home/del/am'
   make: *** [all] Error 2

With the legacy hand-written makefile my project builds just fine.  I'm 
looking for suggestions as to what I'm missing in my Makefile.am.  Note 
that I can explicitly say:

   $ make libb_c_s3.la

and I lo, that library's source(s) compile and link.  So part of the 
generated Makefile is cool.

Thanks,
-Del