Use $(MAKE) instead of make to invoke recursively

Makefile.include

@@ -315,8 +315,8 @@ clean:
 
 distclean:
 	@for TARG in `ls $(CONTIKI)/arch/platform $(TARGETDIRS)`; do \
-		echo Running: make TARGET=$$TARG clean; \
-		make TARGET=$$TARG clean; \
+		echo Running: $(MAKE) TARGET=$$TARG clean; \
+		$(MAKE) TARGET=$$TARG clean; \
 	done
 
 -include $(CONTIKI)/arch/platform/$(TARGET)/Makefile.customrules-$(TARGET)

Makefile.tools

@@ -11,7 +11,7 @@ TUNSLIP6 = $(SERIAL_IO_TOOL_DIR)/tunslip6
 SERIAL_DUMP_BIN = $(SERIAL_IO_TOOL_DIR)/serialdump
 
 $(SERIAL_DUMP_BIN): $(SERIAL_IO_TOOL_DIR)/serialdump.c $(SERIAL_IO_TOOL_DEPS)
-	make -C $(SERIAL_IO_TOOL_DIR) serialdump
+	$(MAKE) -C $(SERIAL_IO_TOOL_DIR) serialdump
 
 $(TUNSLIP6): $(SERIAL_IO_TOOL_DIR)/tunslip6.c $(SERIAL_IO_TOOL_DEPS)
-	make -C $(SERIAL_IO_TOOL_DIR) tunslip6
+	$(MAKE) -C $(SERIAL_IO_TOOL_DIR) tunslip6

tests/Makefile

@@ -36,7 +36,7 @@ summary: $(SUMMARIES)
 	@cat $(SUMMARIES) > $@
 
 %/summary:
-	@make -C $* summary || true
+	@$(MAKE) -C $* summary || true
 
 clean:
 	rm -f $(SUMMARIES) summary

tests/Makefile.compile-test

@@ -40,7 +40,7 @@ get_target_vars = $(wordlist 2,15,$(subst :, ,$1))
 define dooneexample
 @echo -n Building example $(3): $(1) $(4) for target $(2)
 @((cd $(EXAMPLESDIR)/$(1); \
- make $(4) TARGET=$(2) clean && make -j $(4) TARGET=$(2) WERROR=1) > \
+ $(MAKE) $(4) TARGET=$(2) clean && make -j $(4) TARGET=$(2) WERROR=1) > \
       /dev/null 2>make.err && \
  (echo " -> OK" && printf "%-75s %-40s %-20s TEST OK\n" "$(1)" "$(4)" "$(2)" > $(3)-$(subst /,-,$(1))$(2).testlog) || \
  (echo " -> FAIL" && printf "%-75s %-40s %-20s TEST FAIL\n" "$(1)" "$(4)" "$(2)" > $(3)-$(subst /,-,$(1))$(2).testlog ; cat make.err))
@@ -65,4 +65,4 @@ clean:
 	@rm -f *.testlog summary
 	@$(foreach example, $(EXAMPLES), \
            $(foreach target, $(EXAMPLESTARGETS), \
-             (cd $(EXAMPLESDIR)/$(example); make TARGET=$(target) clean);))
+             (cd $(EXAMPLESDIR)/$(example); $(MAKE) TARGET=$(target) clean);))