build: reduced PX4 warnings and avoid rebuilding when possible

mk/px4_targets.mk

@@ -32,16 +32,20 @@ PX4_V2_CONFIG_FILE=$(MK_DIR)/PX4/config_px4fmu-v2_APM.mk
 
 SKETCHFLAGS=$(SKETCHLIBINCLUDES) -I$(PWD) -DARDUPILOT_BUILD -DCONFIG_HAL_BOARD=HAL_BOARD_PX4 -DSKETCHNAME="\\\"$(SKETCH)\\\"" -DSKETCH_MAIN=ArduPilot_main
 
-PX4_MAKE = make -C $(SKETCHBOOK) -f $(PX4_ROOT)/Makefile EXTRADEFINES="$(SKETCHFLAGS) "'$(EXTRAFLAGS)' APM_MODULE_DIR=$(SKETCHBOOK) SKETCHBOOK=$(SKETCHBOOK) PX4_ROOT=$(PX4_ROOT) NUTTX_SRC=$(NUTTX_SRC) MAXOPTIMIZATION="-Os"
+WARNFLAGS = -Wno-psabi
+
+PX4_MAKE = $(v) make -C $(SKETCHBOOK) -f $(PX4_ROOT)/Makefile EXTRADEFINES="$(SKETCHFLAGS) $(WARNFLAGS) "'$(EXTRAFLAGS)' APM_MODULE_DIR=$(SKETCHBOOK) SKETCHBOOK=$(SKETCHBOOK) PX4_ROOT=$(PX4_ROOT) NUTTX_SRC=$(NUTTX_SRC) MAXOPTIMIZATION="-Os"
 PX4_MAKE_ARCHIVES = make -C $(PX4_ROOT) NUTTX_SRC=$(NUTTX_SRC) archives MAXOPTIMIZATION="-Os"
 
 .PHONY: module_mk
 module_mk:
 	$(RULEHDR)
-	$(v) echo "# Auto-generated file - do not edit" > $(SKETCHBOOK)/module.mk
-	$(v) echo "MODULE_COMMAND = ArduPilot" >> $(SKETCHBOOK)/module.mk
-	$(v) echo "SRCS = Build.$(SKETCH)/$(SKETCH).cpp $(SKETCHLIBSRCSRELATIVE)" >> $(SKETCHBOOK)/module.mk
-	$(v) echo "MODULE_STACKSIZE = 4096" >> $(SKETCHBOOK)/module.mk
+	$(v) echo "# Auto-generated file - do not edit" > $(SKETCHBOOK)/module.mk.new
+	$(v) echo "MODULE_COMMAND = ArduPilot" >> $(SKETCHBOOK)/module.mk.new
+	$(v) echo "SRCS = Build.$(SKETCH)/$(SKETCH).cpp $(SKETCHLIBSRCSRELATIVE)" >> $(SKETCHBOOK)/module.mk.new
+	$(v) echo "MODULE_STACKSIZE = 4096" >> $(SKETCHBOOK)/module.mk.new
+	$(v) cmp $(SKETCHBOOK)/module.mk $(SKETCHBOOK)/module.mk.new 2>/dev/null || mv $(SKETCHBOOK)/module.mk.new $(SKETCHBOOK)/module.mk
+	$(v) rm -f $(SKETCHBOOK)/module.mk.new
 
 px4-v1: showflags $(PX4_ROOT)/Archives/px4fmu-v1.export $(SKETCHCPP) module_mk px4-io-v1
 	$(RULEHDR)

mk/sketch_sources.mk

@@ -70,10 +70,12 @@ showflags:
 $(SKETCHCPP): showflags $(SKETCHCPP_SRC)
 	@echo "building $(SKETCHCPP)"
 	$(RULEHDR)
-	$(v)$(AWK) -v mode=header '$(SKETCH_SPLITTER)'   $(SKETCHCPP_SRC) >  $@
-	$(v)echo "#line 1 \"autogenerated\""                              >> $@
-	$(v)$(AWK)                '$(SKETCH_PROTOTYPER)' $(SKETCHCPP_SRC) >> $@
-	$(v)$(AWK) -v mode=body   '$(SKETCH_SPLITTER)'   $(SKETCHCPP_SRC) >> $@
+	$(v)$(AWK) -v mode=header '$(SKETCH_SPLITTER)'   $(SKETCHCPP_SRC) >  $@.new
+	$(v)echo "#line 1 \"autogenerated\""                              >> $@.new
+	$(v)$(AWK)                '$(SKETCH_PROTOTYPER)' $(SKETCHCPP_SRC) >> $@.new
+	$(v)$(AWK) -v mode=body   '$(SKETCH_SPLITTER)'   $(SKETCHCPP_SRC) >> $@.new
+	$(v)cmp $@ $@.new 2>/dev/null || mv $@.new $@
+	$(v)rm -f $@.new
 
 # delete the sketch.cpp file if a processing error occurs
 .DELETE_ON_ERROR: $(SKETCHCPP)