Fix concurrent creation of `recursive-*deps-list.log` files

To do that, we simply include the PID of the Make process in temporary
file.

We also compare the finished temporary file with the actual target file.
If they are different, the temporary file is moved to the final target,
otherwise, we just get rid of the temporary file. This way, the target
timestamp stays the same if the content does not change.

core/deps-tools.mk

@@ -53,7 +53,7 @@ ifneq ($(filter shell,$(DEP_TYPES)),)
 $(ERLANG_MK_RECURSIVE_DEPS_LIST): $(ALL_SHELL_DEPS_DIRS)
 endif
 
-ERLANG_MK_RECURSIVE_TMP_LIST := $(abspath $(ERLANG_MK_TMP)/recursive-tmp-deps.log)
+ERLANG_MK_RECURSIVE_TMP_LIST := $(abspath $(ERLANG_MK_TMP)/recursive-tmp-deps-$(shell echo $$PPID).log)
 
 $(ERLANG_MK_RECURSIVE_DEPS_LIST) \
 $(ERLANG_MK_RECURSIVE_DOC_DEPS_LIST) \
@@ -82,7 +82,11 @@ endif
 		fi \
 	done
 ifeq ($(IS_APP)$(IS_DEP),)
-	$(verbose) sort < $(ERLANG_MK_RECURSIVE_TMP_LIST) | uniq > $@
+	$(verbose) sort < $(ERLANG_MK_RECURSIVE_TMP_LIST) | \
+		uniq > $(ERLANG_MK_RECURSIVE_TMP_LIST).sorted
+	$(verbose) cmp -s $(ERLANG_MK_RECURSIVE_TMP_LIST).sorted $@ \
+		|| mv $(ERLANG_MK_RECURSIVE_TMP_LIST).sorted $@
+	$(verbose) rm -f $(ERLANG_MK_RECURSIVE_TMP_LIST).sorted
 	$(verbose) rm $(ERLANG_MK_RECURSIVE_TMP_LIST)
 endif
 endif # ifneq ($(SKIP_DEPS),)