os,dix: Depend custom libs on libs, not objects

The custom os/os.O library reuses *.o files of os/libos.la.

The current rule assumes automake puts all the objects into per-target
am__*_la_OBJECTS variable.  At least with AC_REPLACE_FUNCS, this no
longer holds (as wanted objects are put into LTLIBOBJS instead).

Depend on automake's result, the *.la library instead, to express demand
of any its dependencies being built.

Should be fixing randomly occuring "undefined reference to `strlcpy'"
errors when linking Xvfb and other DDX-es that could use os.O.

Reviewed-by: Adam Jackson <ajax@redhat.com>
Signed-off-by: Mihail Konev <k.mvc@ya.ru>

dix/Makefile.am

@@ -61,13 +61,13 @@ endif
 
 if SPECIAL_DTRACE_OBJECTS
 # Generate dtrace object code for probes in libdix
-dtrace-dix.o: $(top_srcdir)/dix/Xserver.d $(am_libdix_la_OBJECTS)
+dtrace-dix.o: $(top_srcdir)/dix/Xserver.d libdix.la
 	$(AM_V_GEN)$(DTRACE) -G -C -o $@ -s $(top_srcdir)/dix/Xserver.d $(am_libdix_la_OBJECTS:%.lo=.libs/%.o)
 
 noinst_PROGRAMS = dix.O
 
 dix_O_SOURCES =
-dix.O: dtrace-dix.o $(am_libdix_la_OBJECTS)
+dix.O: dtrace-dix.o libdix.la
 	$(AM_V_GEN)ld -r -o $@ $(am_libdix_la_OBJECTS:%.lo=.libs/%.o)
 endif
 

os/Makefile.am

@@ -58,12 +58,12 @@ EXTRA_DIST = $(SECURERPC_SRCS) $(XDMCP_SRCS)
 
 if SPECIAL_DTRACE_OBJECTS
 # Generate dtrace object code for probes in libos & libdix
-dtrace.o: $(top_srcdir)/dix/Xserver.d $(am_libos_la_OBJECTS)
+dtrace.o: $(top_srcdir)/dix/Xserver.d libos.la
 	$(AM_V_GEN)$(DTRACE) -G -C -o $@ -s $(top_srcdir)/dix/Xserver.d .libs/*.o ../dix/.libs/*.o
 
 noinst_PROGRAMS = os.O
 
 os_O_SOURCES =
-os.O: dtrace.o $(am_libos_la_OBJECTS)
+os.O: dtrace.o libos.la
 	$(AM_V_GEN)ld -r -o $@ dtrace.o .libs/*.o
 endif