fix parallel builds

Makefile.rules

@@ -60,9 +60,8 @@ ALLDEP+=makecfg.lst
 # returns current type: "" core/unknown, "M" module, "L" libray, "U" util
 crt_type=$(if $(MOD_NAME),M,$(if $(LIB_NAME),L,$(if $(UTIL_NAME),U)))
 
-cmd_CC=$(CC) $(CFLAGS) $(C_INCLUDES) $(INCLUDES) $(C_DEFS) $(DEFS) -c $< -o $@
-cmd_LD=$(LD) $(LDFLAGS) $(objs) $(extra_objs) $(ALL_LIBS) $(SER_RPATH) \
-	-o $(NAME)
+cmd_CC=$(CC) $(CFLAGS) $(C_INCLUDES) $(INCLUDES) $(C_DEFS) $(DEFS) -c $<
+cmd_LD=$(LD) $(LDFLAGS) $(objs) $(extra_objs) $(ALL_LIBS) $(SER_RPATH)
 
 ifeq (,$(CC_MKDEP_OPTS))
 # if CCC_MKDEP_OPTS is empty => CC cannot generate dependencies on the fly
@@ -77,6 +76,21 @@ cmd_CC+=$(CC_MKDEP_OPTS)
 cmd_MKDEP=
 endif # CC_MKDEP_OPTS
 
+cmd_CC+=-o $@.tmp || rm -f $@.tmp; mv -f $@.tmp $@ 2> /dev/null
+cmd_LD+=-o $(NAME).tmp || rm -f $(NAME).tmp; mv -f $(NAME).tmp $(NAME) 2> /dev/null
+
+cmd_CC_lock=while true; do ( flock -n 9 || exit 95; \
+	$(cmd_CC); \
+	) 9> $@.lock; exitcode=$$?; test $$exitcode = 95 || break; sleep 1; \
+	test -e $@ && exit 0; done; \
+	rm -f $@.lock; exit $$exitcode
+cmd_LD_lock=while true; do ( flock -n 9 || exit 95; \
+	$(cmd_LD); \
+	) 9> $@.lock; exitcode=$$?; test $$exitcode = 95 || break; sleep 1; \
+	test -e $@ && exit 0; done; \
+	rm -f $@.lock; exit $$exitcode
+
+
 # what will be displayed if quiet==silent
 silent_cmd_CC=CC ($(CC)) [$(strip $(crt_type) $(NAME))]		$@
 silent_cmd_LD=LD ($(LD)) [$(strip $(crt_type) $(NAME))]		$@
@@ -107,7 +121,7 @@ module_make=	if [ -n "$(1)" -a -r "$(1)/Makefile" ]; then \
 quote:= "
 escall= $(subst $$,\$$,$(subst $(quote),\$(quote),$1))
 exec_cmd= $(if $($(quiet)_cmd_$(1)),\
-			@echo "$(call escall,$($(quiet)_cmd_$(1)))" ;) $(cmd_$(1))
+			@echo "$(call escall,$($(quiet)_cmd_$(1)))" ;) $(cmd_$(1)_lock)
 
 #implicit rules
 %.o:%.c  $(ALLDEP)