Libguestfs - Mar 2014 - Re: [PATCH] Fix building on architectures where ocamlopt is not available

---
 builder/Makefile.am        | 18 +++++++++++++-
 configure.ac               |  2 ++
 mllib/Makefile.am          | 60 +++++++++++++++++++++++++++++++---------------
 ocaml/Makefile.am          | 28 +++++++++++++++-------
 ocaml/examples/Makefile.am | 13 ++++++++++
 resize/Makefile.am         | 18 +++++++++++++-
 sparsify/Makefile.am       | 18 +++++++++++++-
 sysprep/Makefile.am        | 18 +++++++++++++-
 8 files changed, 143 insertions(+), 32 deletions(-)

diff --git a/builder/Makefile.am b/builder/Makefile.am
index f0cb1dd..bc7ab6e 100644
--- a/builder/Makefile.am
+++ b/builder/Makefile.am
@@ -68,7 +68,7 @@ noinst_DATA  if HAVE_OCAML
 
 # Note this list must be in dependency order.
-OBJECTS = \
+deps = \
 	$(top_builddir)/mllib/libdir.cmx \
 	$(top_builddir)/mllib/common_gettext.cmx \
 	$(top_builddir)/mllib/common_utils.cmx \
@@ -109,6 +109,12 @@ OBJECTS = \
 	cmdline.cmx \
 	builder.cmx
 
+if HAVE_OCAMLOPT
+OBJECTS = $(deps)
+else
+OBJECTS = $(patsubst %.cmx,%.cmo,$(deps))
+endif
+
 bin_SCRIPTS = virt-builder
 
 # -I $(top_builddir)/src/.libs is a hack which forces corresponding -L
@@ -134,12 +140,22 @@ OCAMLCLIBS  = \
 	-pthread -lpthread \
 	-lncurses -lcrypt
 
+if HAVE_OCAMLOPT
 virt-builder: $(OBJECTS)
 	$(OCAMLFIND) ocamlopt $(OCAMLOPTFLAGS) \
 	  mlguestfs.cmxa -linkpkg $^ \
 	  -cclib '$(OCAMLCLIBS)' \
 	  $(OCAML_GCOV_LDFLAGS) \
 	  -o $@
+else
+virt-builder: $(OBJECTS)
+	$(OCAMLFIND) ocamlc $(OCAMLCFLAGS) \
+	  mlguestfs.cma -linkpkg $^ \
+	  -cclib '$(OCAMLCLIBS)' \
+	  -custom \
+	  $(OCAML_GCOV_LDFLAGS) \
+	  -o $@
+endif
 
 .mli.cmi:
 	$(OCAMLFIND) ocamlc $(OCAMLCFLAGS) -c $< -o $@
diff --git a/configure.ac b/configure.ac
index 0326640..61281f2 100644
--- a/configure.ac
+++ b/configure.ac
@@ -1026,6 +1026,8 @@ AS_IF([test "x$enable_ocaml" !=
"xno"],[
 ])
 AM_CONDITIONAL([HAVE_OCAML],
                [test "x$OCAMLC" != "xno" && test
"x$OCAMLFIND" != "xno"])
+AM_CONDITIONAL([HAVE_OCAMLOPT],
+               [test "x$OCAMLOPT" != "xno" && test
"x$OCAMLFIND" != "xno"])
 AM_CONDITIONAL([HAVE_OCAMLDOC],
                [test "x$OCAMLDOC" != "xno"])
 
diff --git a/mllib/Makefile.am b/mllib/Makefile.am
index 920928d..2e35d1e 100644
--- a/mllib/Makefile.am
+++ b/mllib/Makefile.am
@@ -69,6 +69,25 @@ if HAVE_OCAML
 # - We're not actually building a functioning program here, we're just
 #   linking everything together to check all the modules build OK.
 # - This list must be in dependency order.
+ocaml_modules = config \
+	libdir \
+	common_gettext \
+	common_utils \
+	urandom \
+	random_seed \
+	hostname \
+	timezone \
+	firstboot \
+	perl_edit \
+	tTY \
+	fsync \
+	progress \
+	uRI \
+	crypt \
+	password \
+	mkdtemp \
+	planner
+
 OBJECTS = \
 	$(top_builddir)/fish/guestfish-progress.o \
 	$(top_builddir)/fish/guestfish-uri.o \
@@ -77,25 +96,13 @@ OBJECTS = \
 	progress-c.o \
 	uri-c.o \
 	crypt-c.o \
-	mkdtemp-c.o \
-	config.cmx \
-	libdir.cmx \
-	common_gettext.cmx \
-	common_utils.cmx \
-	urandom.cmx \
-	random_seed.cmx \
-	hostname.cmx \
-	timezone.cmx \
-	firstboot.cmx \
-	perl_edit.cmx \
-	tTY.cmx \
-	fsync.cmx \
-	progress.cmx \
-	uRI.cmx \
-	crypt.cmx \
-	password.cmx \
-	mkdtemp.cmx \
-	planner.cmx
+	mkdtemp-c.o
+
+if HAVE_OCAMLOPT
+OBJECTS += $(patsubst %,%.cmx,$(ocaml_modules))
+else
+OBJECTS += $(patsubst %,%.cmo,$(ocaml_modules))
+endif
 
 noinst_SCRIPTS = dummy
 
@@ -116,11 +123,20 @@ OCAMLCLIBS  = \
 	-L../gnulib/lib/.libs -lgnu
 
 dummy: $(OBJECTS)
+if HAVE_OCAMLOPT
 	$(OCAMLFIND) ocamlopt $(OCAMLOPTFLAGS) \
 	  mlguestfs.cmxa -linkpkg $^ \
 	  -cclib '$(OCAMLCLIBS)' \
 	  $(OCAML_GCOV_LDFLAGS) \
 	  -o $@
+else
+	$(OCAMLFIND) ocamlc $(OCAMLCFLAGS) \
+	  mlguestfs.cma -linkpkg $^ \
+	  -cclib '$(OCAMLCLIBS)' \
+	  -custom \
+	  $(OCAML_GCOV_LDFLAGS) \
+	  -o $@
+endif
 
 .mli.cmi:
 	$(OCAMLFIND) ocamlc $(OCAMLCFLAGS) -c $< -o $@
@@ -153,9 +169,15 @@ DEFAULT_INCLUDES = \
 
 check_SCRIPTS = common_utils_tests
 
+if HAVE_OCAMLOPT
 common_utils_tests: common_gettext.cmx common_utils.cmx common_utils_tests.cmx
 	$(OCAMLFIND) ocamlopt $(OCAMLOPTFLAGS) \
 	  mlguestfs.cmxa -linkpkg $^ -cclib -lncurses -o $@
+else
+common_utils_tests: common_gettext.cmo common_utils.cmo common_utils_tests.cmo
+	$(OCAMLFIND) ocamlc $(OCAMLCFLAGS) \
+	  mlguestfs.cma -linkpkg $^ -cclib -lncurses -o $@
+endif
 
 TESTS_ENVIRONMENT = $(top_builddir)/run --test
 
diff --git a/ocaml/Makefile.am b/ocaml/Makefile.am
index 5dd2c9b..708b2e7 100644
--- a/ocaml/Makefile.am
+++ b/ocaml/Makefile.am
@@ -40,7 +40,10 @@ if HAVE_OCAML
 OCAMLCFLAGS = -g -warn-error CDEFLMPSUVYZX
 OCAMLOPTFLAGS = $(OCAMLCFLAGS)
 
-noinst_DATA = mlguestfs.cma mlguestfs.cmxa META
+noinst_DATA = mlguestfs.cma META
+if HAVE_OCAMLOPT
+noinst_DATA +=  mlguestfs.cmxa
+endif
 
 # Build the C part into a library, so that automake handles the C
 # compilation step for us.  Note that we don't directly use this
@@ -51,18 +54,15 @@ noinst_LIBRARIES = libguestfsocaml.a
 # 'libmlguestfs.a' and if run at the same time, they will stomp on or
 # corrupt each others copy.  Hence we have to serialize the calls.
 
-CLEANFILES += stamp-mlguestfs
-
-mlguestfs.cma mlguestfs.cmxa: stamp-mlguestfs
-
-stamp-mlguestfs: libguestfsocaml.a guestfs.cmo guestfs.cmx
+mlguestfs.cma: libguestfsocaml.a guestfs.cmo
 	$(OCAMLMKLIB) -o mlguestfs \
 	  $(libguestfsocaml_a_OBJECTS) guestfs.cmo \
 	  -L$(top_builddir)/src/.libs -lguestfs
+
+mlguestfs.cmxa: libguestfsocaml.a guestfs.cmx
 	$(OCAMLMKLIB) -o mlguestfs \
 	  $(libguestfsocaml_a_OBJECTS) guestfs.cmx \
 	  -L$(top_builddir)/src/.libs -lguestfs
-	touch $@
 
 libguestfsocaml_a_CPPFLAGS = \
 	-DGUESTFS_PRIVATE=1 \
@@ -121,11 +121,17 @@ test_progs_opt += \
 	t/guestfs_430_progress_messages.opt
 endif
 
-test_progs_all = $(test_progs_bc) $(test_progs_opt)
+test_progs_all = $(test_progs_bc)
+if HAVE_OCAMLOPT
+test_progs_all += $(test_progs_opt)
+endif
 
 TESTS = run-bindtests $(test_progs_all)
 
-noinst_DATA += bindtests.bc bindtests.opt $(test_progs_all)
+noinst_DATA += bindtests.bc $(test_progs_all)
+if HAVE_OCAMLOPT
+noinst_DATA += bindtests.opt
+endif
 
 %.bc: %.cmo mlguestfs.cma
 	$(top_builddir)/libtool -dlopen $(top_builddir)/src/.libs/libguestfs.la
--mode=execute \
@@ -178,3 +184,7 @@ install-data-hook:
 CLEANFILES += $(noinst_DATA)
 
 endif
+
+# Tell version 3.79 and up of GNU make to not build goals in this
+# directory in parallel.
+.NOTPARALLEL:
diff --git a/ocaml/examples/Makefile.am b/ocaml/examples/Makefile.am
index 200a0aa..472e180 100644
--- a/ocaml/examples/Makefile.am
+++ b/ocaml/examples/Makefile.am
@@ -49,6 +49,7 @@ noinst_SCRIPTS = create_disk inspect_vm
 
 OCAMLFINDFLAGS = -cclib -L$(top_builddir)/src/.libs
 
+if HAVE_OCAMLOPT
 create_disk: create_disk.ml
 	$(OCAMLFIND) ocamlopt $(OCAMLFINDFLAGS) -package unix -linkpkg \
           -warn-error A -I .. mlguestfs.cmxa $< -o $@
@@ -56,5 +57,17 @@ create_disk: create_disk.ml
 inspect_vm: inspect_vm.ml
 	$(OCAMLFIND) ocamlopt $(OCAMLFINDFLAGS) -package unix -linkpkg \
           -warn-error A -I .. mlguestfs.cmxa $< -o $@
+else
+
+# This avoids:
+#   Error: Error on dynamically loaded library: ../dllmlguestfs.so:
libguestfs.so.0: cannot open shared object file: No such file or directory
+create_disk: create_disk.ml
+	$(top_builddir)/run $(OCAMLFIND) ocamlc $(OCAMLFINDFLAGS) -package unix
-linkpkg \
+          -warn-error A -I .. mlguestfs.cma $< -o $@
+
+inspect_vm: inspect_vm.ml
+	$(top_builddir)/run $(OCAMLFIND) ocamlc $(OCAMLFINDFLAGS) -package unix
-linkpkg \
+          -warn-error A -I .. mlguestfs.cma $< -o $@
+endif
 
 endif
diff --git a/resize/Makefile.am b/resize/Makefile.am
index 76c26ee..ef35bf9 100644
--- a/resize/Makefile.am
+++ b/resize/Makefile.am
@@ -31,7 +31,7 @@ SOURCES = \
 if HAVE_OCAML
 
 # Note this list must be in dependency order.
-OBJECTS = \
+deps = \
 	$(top_builddir)/mllib/tty-c.o \
 	$(top_builddir)/mllib/tTY.cmx \
 	$(top_builddir)/mllib/fsync-c.o \
@@ -47,6 +47,12 @@ OBJECTS = \
 	$(top_builddir)/mllib/config.cmx \
 	resize.cmx
 
+if HAVE_OCAMLOPT
+OBJECTS = $(deps)
+else
+OBJECTS = $(patsubst %.cmx,%.cmo,$(deps))
+endif
+
 bin_SCRIPTS = virt-resize
 
 # -I $(top_builddir)/src/.libs is a hack which forces corresponding -L
@@ -69,12 +75,22 @@ OCAMLCLIBS  = \
 	-L../src/.libs -lutils \
 	-L../gnulib/lib/.libs -lgnu
 
+if HAVE_OCAMLOPT
 virt-resize: $(OBJECTS)
 	$(OCAMLFIND) ocamlopt $(OCAMLOPTFLAGS) \
 	  mlguestfs.cmxa -linkpkg $^ \
 	  -cclib '$(OCAMLCLIBS)' \
 	  $(OCAML_GCOV_LDFLAGS) \
 	  -o $@
+else
+virt-resize: $(OBJECTS)
+	$(OCAMLFIND) ocamlc $(OCAMLCFLAGS) \
+	  mlguestfs.cma -linkpkg $^ \
+	  -cclib '$(OCAMLCLIBS)' \
+	  -custom \
+	  $(OCAML_GCOV_LDFLAGS) \
+	  -o $@
+endif
 
 .mli.cmi:
 	$(OCAMLFIND) ocamlc $(OCAMLCFLAGS) -c $< -o $@
diff --git a/sparsify/Makefile.am b/sparsify/Makefile.am
index 98d9c70..bf6caf0 100644
--- a/sparsify/Makefile.am
+++ b/sparsify/Makefile.am
@@ -32,7 +32,7 @@ SOURCES = \
 if HAVE_OCAML
 
 # Note this list must be in dependency order.
-OBJECTS = \
+deps = \
 	$(top_builddir)/fish/guestfish-progress.o \
 	$(top_builddir)/mllib/tty-c.o \
 	$(top_builddir)/mllib/progress-c.o \
@@ -44,6 +44,12 @@ OBJECTS = \
 	statvfs-c.o \
 	sparsify.cmx
 
+if HAVE_OCAMLOPT
+OBJECTS = $(deps)
+else
+OBJECTS = $(patsubst %.cmx,%.cmo,$(deps))
+endif
+
 bin_SCRIPTS = virt-sparsify
 
 # -I $(top_builddir)/src/.libs is a hack which forces corresponding -L
@@ -61,12 +67,22 @@ endif
 OCAMLCFLAGS = -g -warn-error CDEFLMPSUVYZX $(OCAMLPACKAGES)
 OCAMLOPTFLAGS = $(OCAMLCFLAGS)
 
+if HAVE_OCAMLOPT
 virt-sparsify: $(OBJECTS)
 	$(OCAMLFIND) ocamlopt $(OCAMLOPTFLAGS) \
 	  mlguestfs.cmxa -linkpkg $^ \
 	  -cclib -lncurses \
 	  $(OCAML_GCOV_LDFLAGS) \
 	  -o $@
+else
+virt-sparsify: $(OBJECTS)
+	$(OCAMLFIND) ocamlc $(OCAMLCFLAGS) \
+	  mlguestfs.cma -linkpkg $^ \
+	  -cclib -lncurses \
+	  -custom \
+	  $(OCAML_GCOV_LDFLAGS) \
+	  -o $@
+endif
 
 .mli.cmi:
 	$(OCAMLFIND) ocamlc $(OCAMLCFLAGS) -c $< -o $@
diff --git a/sysprep/Makefile.am b/sysprep/Makefile.am
index 9c9ab14..22da6fd 100644
--- a/sysprep/Makefile.am
+++ b/sysprep/Makefile.am
@@ -85,7 +85,7 @@ SOURCES = \
 if HAVE_OCAML
 
 # Note this list must be in dependency order.
-OBJECTS = \
+deps = \
 	$(top_builddir)/mllib/common_gettext.cmx \
 	$(top_builddir)/mllib/common_utils.cmx \
 	$(top_builddir)/fish/guestfish-uri.o \
@@ -106,6 +106,12 @@ OBJECTS = \
 	$(patsubst %,sysprep_operation_%.cmx,$(operations)) \
 	main.cmx
 
+if HAVE_OCAMLOPT
+OBJECTS = $(deps)
+else
+OBJECTS = $(patsubst %.cmx,%.cmo,$(deps))
+endif
+
 bin_SCRIPTS = virt-sysprep
 
 # -I $(top_builddir)/src/.libs is a hack which forces corresponding -L
@@ -128,12 +134,22 @@ OCAMLCLIBS  = \
 	-L../src/.libs -lutils \
 	-L../gnulib/lib/.libs -lgnu
 
+if HAVE_OCAMLOPT
 virt-sysprep: $(OBJECTS)
 	$(OCAMLFIND) ocamlopt $(OCAMLOPTFLAGS) \
 	  mlguestfs.cmxa -linkpkg $^ \
 	  -cclib '$(OCAMLCLIBS)' \
 	  $(OCAML_GCOV_LDFLAGS) \
 	  -o $@
+else
+virt-sysprep: $(OBJECTS)
+	$(OCAMLFIND) ocamlc $(OCAMLCFLAGS) \
+	  mlguestfs.cma -linkpkg $^ \
+	  -cclib '$(OCAMLCLIBS)' \
+	  -custom \
+	  $(OCAML_GCOV_LDFLAGS) \
+	  -o $@
+endif
 
 .mli.cmi:
 	$(OCAMLFIND) ocamlc $(OCAMLCFLAGS) -c $< -o $@
-- 
1.9.0

On Fri, Feb 28, 2014 at 02:35:56PM +0100, Hilko Bengen
wrote:
> +if HAVE_OCAMLOPT
> +OBJECTS = $(deps)
> +else
> +OBJECTS = $(patsubst %.cmx,%.cmo,$(deps))
There's something about automake 1.13 which breaks use of patsubst /
subst (or any GNU make extension used in certain automake variables).

I can't test if it will specifically break this because I don't have
access to any machines that don't have ocamlopt, but it's something to
watch out for.

In any case, I have pushed this since it works fine for me.

Something for the future: It'd be nice to use automake to build
objects.  This is possible if the program contains at least one C
object file.  See:
https://github.com/libguestfs/supermin/blob/master/src/Makefile.am#L96
https://github.com/libguestfs/supermin/blob/master/src/supermin-link.sh.in

Thanks,

Rich.

-- 
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
virt-df lists disk usage of guests without needing to install any
software inside the virtual machine.  Supports Linux and Windows.
http://people.redhat.com/~rjones/virt-df/

On Fri, Feb 28, Hilko Bengen wrote:
> ---
>  builder/Makefile.am        | 18 +++++++++++++-
>  configure.ac               |  2 ++
>  mllib/Makefile.am          | 60
+++++++++++++++++++++++++++++++---------------
>  ocaml/Makefile.am          | 28 +++++++++++++++-------
Something like this is required:


diff --git a/ocaml/Makefile.am b/ocaml/Makefile.am
index 708b2e7..698e13a 100644
--- a/ocaml/Makefile.am
+++ b/ocaml/Makefile.am
@@ -37,6 +37,11 @@ CLEANFILES += t/*.cmi t/*.cmo t/*.cmx t/*.o t/*.a t/*.so
 
 if HAVE_OCAML
 
+DATA_HOOK_FILES = META *.so *.a *.cma *.cmi $(srcdir)/*.mli
+if HAVE_OCAMLOPT
+DATA_HOOK_FILES += *.cmx *.cmxa
+endif
+
 OCAMLCFLAGS = -g -warn-error CDEFLMPSUVYZX
 OCAMLOPTFLAGS = $(OCAMLCFLAGS)
 
@@ -177,7 +182,7 @@ install-data-hook:
 	$(OCAMLFIND) install \
 	  -ldconf ignore -destdir $(DESTDIR)$(OCAMLLIB) \
 	  guestfs \
-	  META *.so *.a *.cma *.cmx *.cmxa *.cmi $(srcdir)/*.mli
+	  $(DATA_HOOK_FILES)
 	rm $(DESTDIR)$(OCAMLLIB)/guestfs/bindtests.*
 	rm $(DESTDIR)$(OCAMLLIB)/guestfs/libguestfsocaml.a

On Fri, Feb 28, 2014 at 03:53:55PM +0100, Olaf Hering
wrote:
> On Fri, Feb 28, Hilko Bengen wrote:
> 
> > ---
> >  builder/Makefile.am        | 18 +++++++++++++-
> >  configure.ac               |  2 ++
> >  mllib/Makefile.am          | 60
+++++++++++++++++++++++++++++++---------------
> >  ocaml/Makefile.am          | 28 +++++++++++++++-------
> 
> Something like this is required:
> 
> 
> diff --git a/ocaml/Makefile.am b/ocaml/Makefile.am
> index 708b2e7..698e13a 100644
> --- a/ocaml/Makefile.am
> +++ b/ocaml/Makefile.am
> @@ -37,6 +37,11 @@ CLEANFILES += t/*.cmi t/*.cmo t/*.cmx t/*.o t/*.a t/*.so
>  
>  if HAVE_OCAML
>  
> +DATA_HOOK_FILES = META *.so *.a *.cma *.cmi $(srcdir)/*.mli
> +if HAVE_OCAMLOPT
> +DATA_HOOK_FILES += *.cmx *.cmxa
> +endif
> +
>  OCAMLCFLAGS = -g -warn-error CDEFLMPSUVYZX
>  OCAMLOPTFLAGS = $(OCAMLCFLAGS)
>  
> @@ -177,7 +182,7 @@ install-data-hook:
>  	$(OCAMLFIND) install \
>  	  -ldconf ignore -destdir $(DESTDIR)$(OCAMLLIB) \
>  	  guestfs \
> -	  META *.so *.a *.cma *.cmx *.cmxa *.cmi $(srcdir)/*.mli
> +	  $(DATA_HOOK_FILES)
>  	rm $(DESTDIR)$(OCAMLLIB)/guestfs/bindtests.*
>  	rm $(DESTDIR)$(OCAMLLIB)/guestfs/libguestfsocaml.a
Looks reasonable to me.

Rich.

-- 
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
virt-top is 'top' for virtual machines.  Tiny program with many
powerful monitoring features, net stats, disk stats, logging, etc.
http://people.redhat.com/~rjones/virt-top

On Fri, Feb 28, Richard W.M. Jones wrote:
> I can't test if it will specifically break this because I don't
have
> access to any machines that don't have ocamlopt, but it's something
to
> watch out for.
> 
> In any case, I have pushed this since it works fine for me.
Any chance this can be backported to 1.24?

Olaf

On Fri, Feb 28, 2014 at 02:35:56PM +0100, Hilko Bengen
wrote:
> diff --git a/ocaml/Makefile.am b/ocaml/Makefile.am
> index 5dd2c9b..708b2e7 100644
> --- a/ocaml/Makefile.am
> +++ b/ocaml/Makefile.am
[...]
> +# Tell version 3.79 and up of GNU make to not build goals in this
> +# directory in parallel.
> +.NOTPARALLEL:
^ This makes building the OCaml subdirectory very slow (I normally
build with MAKEFLAGS=-j9).  Was there a reason for adding this?

Rich.

-- 
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
Fedora Windows cross-compiler. Compile Windows programs, test, and
build Windows installers. Over 100 libraries supported.
http://fedoraproject.org/wiki/MinGW

* Richard W.M. Jones:
> On Fri, Feb 28, 2014 at 02:35:56PM +0100, Hilko Bengen wrote:
>> diff --git a/ocaml/Makefile.am b/ocaml/Makefile.am
>> index 5dd2c9b..708b2e7 100644
>> --- a/ocaml/Makefile.am
>> +++ b/ocaml/Makefile.am
> [...]
>> +# Tell version 3.79 and up of GNU make to not build goals in this
>> +# directory in parallel.
>> +.NOTPARALLEL:
>
> ^ This makes building the OCaml subdirectory very slow (I normally
> build with MAKEFLAGS=-j9).  Was there a reason for adding this?
I think I added this because both the mlguestfs.cma and mlguestfs.cmxa
targets generate libmlguestfs.a:

mlguestfs.cma: libguestfsocaml.a guestfs.cmo
	$(OCAMLMKLIB) -o mlguestfs \
	  $(libguestfsocaml_a_OBJECTS) guestfs.cmo \
	  -L$(top_builddir)/src/.libs -lguestfs

mlguestfs.cmxa: libguestfsocaml.a guestfs.cmx
	$(OCAMLMKLIB) -o mlguestfs \
	  $(libguestfsocaml_a_OBJECTS) guestfs.cmx \
	  -L$(top_builddir)/src/.libs -lguestfs

As far as I know, those are the only targets that shouldn't be run
parallel. 

I think that an extra target (mlguestfs.cmxa: mlguestfs.cma) would make
the .NOTPARALLEL unnecessary.

Cheers,
-Hilko