diff --git a/Marlin/Makefile b/Marlin/Makefile
index 1315a9d4328f8cdfb02ff9a373cd0822c3668eff..626e387c6ef76688aa4ab41acee7ac6f9fe1f225 100644
--- a/Marlin/Makefile
+++ b/Marlin/Makefile
@@ -229,6 +229,22 @@ OPT = s
 
 DEFINES ?=
 
+# Program settings
+CC = $(AVR_TOOLS_PATH)avr-gcc
+CXX = $(AVR_TOOLS_PATH)avr-g++
+OBJCOPY = $(AVR_TOOLS_PATH)avr-objcopy
+OBJDUMP = $(AVR_TOOLS_PATH)avr-objdump
+AR  = $(AVR_TOOLS_PATH)avr-ar
+SIZE = $(AVR_TOOLS_PATH)avr-size
+NM = $(AVR_TOOLS_PATH)avr-nm
+AVRDUDE = avrdude
+REMOVE = rm -f
+MV = mv -f
+
+# Tool for testing compiler flags
+cc-option=$(shell if test -z "`$(1) $(2) -S -o /dev/null -xc /dev/null 2>&1`" \
+    ; then echo "$(2)"; else echo "$(3)"; fi ;)
+
 # Place -D or -U options here
 CDEFS    = -DF_CPU=$(F_CPU) ${addprefix -D , $(DEFINES)}
 CXXDEFS  = $(CDEFS)
@@ -259,10 +275,12 @@ CTUNING += -DMOTHERBOARD=${HARDWARE_MOTHERBOARD}
 endif
 #CEXTRA = -Wa,-adhlns=$(<:.c=.lst)
 
-CFLAGS = $(CDEBUG) $(CDEFS) $(CINCS) -O$(OPT) $(CWARN) $(CEXTRA) $(CTUNING)
-CXXFLAGS =         $(CDEFS) $(CINCS) -O$(OPT) -Wall    $(CEXTRA) $(CTUNING)
+CFLAGS := $(CDEBUG) $(CDEFS) $(CINCS) -O$(OPT) $(CWARN) $(CEXTRA) $(CTUNING) \
+    $(call cc-option,$(CC),-flto -fwhole-program,)
+CXXFLAGS :=         $(CDEFS) $(CINCS) -O$(OPT) -Wall    $(CEXTRA) $(CTUNING) \
+    $(call cc-option,$(CC),-flto -fwhole-program,)
 #ASFLAGS = -Wa,-adhlns=$(<:.S=.lst),-gstabs 
-LDFLAGS = -lm
+LDFLAGS = -lm -Wl,--relax
 
 
 # Programming support using avrdude. Settings and variables.
@@ -272,18 +290,6 @@ AVRDUDE_FLAGS = -D -C $(ARDUINO_INSTALL_DIR)/hardware/tools/avrdude.conf \
 	-p $(MCU) -P $(AVRDUDE_PORT) -c $(AVRDUDE_PROGRAMMER) \
 	-b $(UPLOAD_RATE)
 
-# Program settings
-CC = $(AVR_TOOLS_PATH)avr-gcc
-CXX = $(AVR_TOOLS_PATH)avr-g++
-OBJCOPY = $(AVR_TOOLS_PATH)avr-objcopy
-OBJDUMP = $(AVR_TOOLS_PATH)avr-objdump
-AR  = $(AVR_TOOLS_PATH)avr-ar
-SIZE = $(AVR_TOOLS_PATH)avr-size
-NM = $(AVR_TOOLS_PATH)avr-nm
-AVRDUDE = avrdude
-REMOVE = rm -f
-MV = mv -f
-
 # Define all object files.
 OBJ = ${patsubst %.c, $(BUILD_DIR)/%.o, ${SRC}}
 OBJ += ${patsubst %.cpp, $(BUILD_DIR)/%.o, ${CXXSRC}}
@@ -380,9 +386,13 @@ extcoff: $(TARGET).elf
 	$(NM) -n $< > $@
 
 	# Link: create ELF output file from library.
-$(BUILD_DIR)/$(TARGET).elf: $(OBJ) Configuration.h
+$(BUILD_DIR)/$(TARGET).elf: $(BUILD_DIR)/$(TARGET).o
+	$(Pecho) "  CXX   $@"
+	$P $(CC) $(ALL_CXXFLAGS) -Wl,--gc-sections -o $@ -L. $^ $(LDFLAGS)
+
+$(BUILD_DIR)/$(TARGET).o: $(OBJ) Configuration.h
 	$(Pecho) "  CXX   $@"
-	$P $(CC) $(ALL_CXXFLAGS) -Wl,--gc-sections -o $@ -L. $(OBJ) $(LDFLAGS)
+	$P $(CC) $(ALL_CXXFLAGS) -nostdlib -Wl,-r -o $@ $(OBJ)
 
 $(BUILD_DIR)/%.o: %.c Configuration.h Configuration_adv.h $(MAKEFILE)
 	$(Pecho) "  CC    $<"
diff --git a/Marlin/temperature.cpp b/Marlin/temperature.cpp
index 5a0762d9f1bd2573e1050007616c20c025a0b3bc..61876721625f047f488c5d5e58b95c7363cfed26 100644
--- a/Marlin/temperature.cpp
+++ b/Marlin/temperature.cpp
@@ -432,9 +432,9 @@ void manage_heater()
 	    soft_pwm_bed = 0;
 	  }
 
-    #elif not defined BED_LIMIT_SWITCHING
+    #elif !defined(BED_LIMIT_SWITCHING)
       // Check if temperature is within the correct range
-      if((current_temperature_bed > BED_MAXTEMP) && (current_temperature_bed < BED_MINTEMP))
+      if((current_temperature_bed > BED_MINTEMP) && (current_temperature_bed < BED_MAXTEMP))
       {
         if(current_temperature_bed >= target_temperature_bed)
         {
@@ -1042,6 +1042,7 @@ ISR(TIMER0_COMPB_vect)
 #if EXTRUDERS > 2
       current_temperature_raw[2] = raw_temp_2_value;
 #endif
+      current_temperature_bed_raw = raw_temp_bed_value;
     }
     
     temp_meas_ready = true;
@@ -1101,9 +1102,9 @@ ISR(TIMER0_COMPB_vect)
   /* No bed MINTEMP error? */
 #if defined(BED_MAXTEMP) && (TEMP_SENSOR_BED != 0)
 # if HEATER_BED_RAW_LO_TEMP > HEATER_BED_RAW_HI_TEMP
-    if(current_temperature_bed <= bed_maxttemp_raw) {
+    if(current_temperature_bed_raw <= bed_maxttemp_raw) {
 #else
-    if(current_temperature_bed >= bed_maxttemp_raw) {
+    if(current_temperature_bed_raw >= bed_maxttemp_raw) {
 #endif
        target_temperature_bed = 0;
        bed_max_temp_error();
diff --git a/Marlin/thermistortables.h b/Marlin/thermistortables.h
index d963afff1a0d46776744b099a1c13a676a3ce105..cdf591b2c43ea4b05d7617b4b7d22780ad1fdbe0 100644
--- a/Marlin/thermistortables.h
+++ b/Marlin/thermistortables.h
@@ -474,7 +474,7 @@ const short temptable_55[][2] PROGMEM = {
 
 //Set the high and low raw values for the heater, this indicates which raw value is a high or low temperature
 #ifndef HEATER_0_RAW_HI_TEMP
-# if HEATER_0_USES_THERMISTOR   //In case of a thermistor the highest temperature results in the lowest ADC value
+# ifdef HEATER_0_USES_THERMISTOR   //In case of a thermistor the highest temperature results in the lowest ADC value
 #  define HEATER_0_RAW_HI_TEMP 0
 #  define HEATER_0_RAW_LO_TEMP 16383
 # else                          //In case of an thermocouple the highest temperature results in the highest ADC value
@@ -497,7 +497,7 @@ const short temptable_55[][2] PROGMEM = {
 
 //Set the high and low raw values for the heater, this indicates which raw value is a high or low temperature
 #ifndef HEATER_1_RAW_HI_TEMP
-# if HEATER_1_USES_THERMISTOR   //In case of a thermistor the highest temperature results in the lowest ADC value
+# ifdef HEATER_1_USES_THERMISTOR   //In case of a thermistor the highest temperature results in the lowest ADC value
 #  define HEATER_1_RAW_HI_TEMP 0
 #  define HEATER_1_RAW_LO_TEMP 16383
 # else                          //In case of an thermocouple the highest temperature results in the highest ADC value
@@ -520,7 +520,7 @@ const short temptable_55[][2] PROGMEM = {
 
 //Set the high and low raw values for the heater, this indicates which raw value is a high or low temperature
 #ifndef HEATER_2_RAW_HI_TEMP
-# if HEATER_2_USES_THERMISTOR   //In case of a thermistor the highest temperature results in the lowest ADC value
+# ifdef HEATER_2_USES_THERMISTOR   //In case of a thermistor the highest temperature results in the lowest ADC value
 #  define HEATER_2_RAW_HI_TEMP 0
 #  define HEATER_2_RAW_LO_TEMP 16383
 # else                          //In case of an thermocouple the highest temperature results in the highest ADC value
@@ -540,7 +540,7 @@ const short temptable_55[][2] PROGMEM = {
 
 //Set the high and low raw values for the heater, this indicates which raw value is a high or low temperature
 #ifndef HEATER_BED_RAW_HI_TEMP
-# if BED_USES_THERMISTOR   //In case of a thermistor the highest temperature results in the lowest ADC value
+# ifdef BED_USES_THERMISTOR   //In case of a thermistor the highest temperature results in the lowest ADC value
 #  define HEATER_BED_RAW_HI_TEMP 0
 #  define HEATER_BED_RAW_LO_TEMP 16383
 # else                          //In case of an thermocouple the highest temperature results in the highest ADC value
diff --git a/Marlin/ultralcd.cpp b/Marlin/ultralcd.cpp
index 49cbe996da9a63c08d4438e1257f58973c10966a..beb79beeebf4745df0b3a56058cfd1beda097781 100644
--- a/Marlin/ultralcd.cpp
+++ b/Marlin/ultralcd.cpp
@@ -476,7 +476,7 @@ static void lcd_control_temperature_preheat_pla_settings_menu()
 #if TEMP_SENSOR_BED != 0
     MENU_ITEM_EDIT(int3, MSG_BED, &plaPreheatHPBTemp, 0, BED_MAXTEMP - 15);
 #endif
-#if EEPROM_SETTINGS
+#ifdef EEPROM_SETTINGS
     MENU_ITEM(function, MSG_STORE_EPROM, Config_StoreSettings);
 #endif
     END_MENU();
@@ -491,7 +491,7 @@ static void lcd_control_temperature_preheat_abs_settings_menu()
 #if TEMP_SENSOR_BED != 0
     MENU_ITEM_EDIT(int3, MSG_BED, &absPreheatHPBTemp, 0, BED_MAXTEMP - 15);
 #endif
-#if EEPROM_SETTINGS
+#ifdef EEPROM_SETTINGS
     MENU_ITEM(function, MSG_STORE_EPROM, Config_StoreSettings);
 #endif
     END_MENU();