Merge pull request #1735 from AnHardt/compilerCandy

Remove some further warnings

Marlin/dogm_lcd_implementation.h

 }
 
 static void lcd_implementation_status_screen() {
-
-  static unsigned char fan_rot = 0;
- 
   u8g.setColorIndex(1); // black on white
 
   // Symbols menu graphics, animated fan
   lcd_implementation_mark_as_selected(row, isSelected);
 
   if (isDir) lcd_print(LCD_STR_FOLDER[0]);
-  while (c = *filename) {
+  while ((c = *filename)) {
     n -= lcd_print(c);
     filename++;
   }

Marlin/stepper.cpp

       #ifdef COREXY
         // Head direction in -X axis for CoreXY bots.
         // If DeltaX == -DeltaY, the movement is only in Y axis
-        if (current_block->steps[A_AXIS] != current_block->steps[B_AXIS] || (TEST(out_bits, A_AXIS) == TEST(out_bits, B_AXIS)))
+        if ((current_block->steps[A_AXIS] != current_block->steps[B_AXIS]) || (TEST(out_bits, A_AXIS) == TEST(out_bits, B_AXIS))) {
           if (TEST(out_bits, X_HEAD))
       #else
           if (TEST(out_bits, X_AXIS))   // stepping along -X axis (regular cartesians bot)
               }
           }
       #ifdef COREXY
+        }
         // Head direction in -Y axis for CoreXY bots.
         // If DeltaX == DeltaY, the movement is only in X axis
-        if (current_block->steps[A_AXIS] != current_block->steps[B_AXIS] || (TEST(out_bits, A_AXIS) != TEST(out_bits, B_AXIS)))
+        if ((current_block->steps[A_AXIS] != current_block->steps[B_AXIS]) || (TEST(out_bits, A_AXIS) != TEST(out_bits, B_AXIS))) {
           if (TEST(out_bits, Y_HEAD))
       #else
           if (TEST(out_bits, Y_AXIS))   // -direction
               UPDATE_ENDSTOP(y, Y, max, MAX);
             #endif
           }
+      #ifdef COREXY
+        }
+      #endif
     }
 
     if (TEST(out_bits, Z_AXIS)) {   // -direction

Marlin/temperature.cpp

 #ifdef FILAMENT_SENSOR
   int current_raw_filwidth = 0;  //Holds measured filament diameter - one extruder only
 #endif  
+#if defined (THERMAL_RUNAWAY_PROTECTION_PERIOD) && THERMAL_RUNAWAY_PROTECTION_PERIOD > 0
+void thermal_runaway_protection(int *state, unsigned long *timer, float temperature, float target_temperature, int heater_id, int period_seconds, int hysteresis_degc);
+static int thermal_runaway_state_machine[4]; // = {0,0,0,0};
+static unsigned long thermal_runaway_timer[4]; // = {0,0,0,0};
+static bool thermal_runaway = false;
+#if TEMP_SENSOR_BED != 0
+  static int thermal_runaway_bed_state_machine;
+  static unsigned long thermal_runaway_bed_timer;
+#endif
+#endif
+
 //===========================================================================
 //=============================private variables============================
 //===========================================================================
 }
 
 #ifdef HEATER_0_USES_MAX6675
-  #define MAX6675_HEAT_INTERVAL 250
-  long max6675_previous_millis = MAX6675_HEAT_INTERVAL;
+  #define MAX6675_HEAT_INTERVAL 250u
+  unsigned long max6675_previous_millis = MAX6675_HEAT_INTERVAL;
   int max6675_temp = 2000;
 
   static int read_max6675() {

Marlin/temperature.h

 void setWatch();
 void updatePID();
 
-#if defined (THERMAL_RUNAWAY_PROTECTION_PERIOD) && THERMAL_RUNAWAY_PROTECTION_PERIOD > 0
-void thermal_runaway_protection(int *state, unsigned long *timer, float temperature, float target_temperature, int heater_id, int period_seconds, int hysteresis_degc);
-static int thermal_runaway_state_machine[4]; // = {0,0,0,0};
-static unsigned long thermal_runaway_timer[4]; // = {0,0,0,0};
-static bool thermal_runaway = false;
-#if TEMP_SENSOR_BED != 0
-  static int thermal_runaway_bed_state_machine;
-  static unsigned long thermal_runaway_bed_timer;
-#endif
-#endif
+void PID_autotune(float temp, int extruder, int ncycles);
+
+void setExtruderAutoFanState(int pin, bool state);
+void checkExtruderAutoFans();
 
 FORCE_INLINE void autotempShutdown() {
   #ifdef AUTOTEMP
   #endif
 }
 
-void PID_autotune(float temp, int extruder, int ncycles);
-
-void setExtruderAutoFanState(int pin, bool state);
-void checkExtruderAutoFans();
 
 #endif

Marlin/ultralcd_st7920_u8glib_rrd.h

 #define ST7920_NCS()             {WRITE(ST7920_CS_PIN,0);}
 #define ST7920_SET_CMD()         {ST7920_SWSPI_SND_8BIT(0xf8);u8g_10MicroDelay();}
 #define ST7920_SET_DAT()         {ST7920_SWSPI_SND_8BIT(0xfa);u8g_10MicroDelay();}
-#define ST7920_WRITE_BYTE(a)     {ST7920_SWSPI_SND_8BIT((a)&0xf0);ST7920_SWSPI_SND_8BIT((a)<<4);u8g_10MicroDelay();}
+#define ST7920_WRITE_BYTE(a)     {ST7920_SWSPI_SND_8BIT((uint8_t)((a)&0xf0u));ST7920_SWSPI_SND_8BIT((uint8_t)((a)<<4u));u8g_10MicroDelay();}
 #define ST7920_WRITE_BYTES(p,l)  {uint8_t i;for(i=0;i<l;i++){ST7920_SWSPI_SND_8BIT(*p&0xf0);ST7920_SWSPI_SND_8BIT(*p<<4);p++;}u8g_10MicroDelay();}
 
 uint8_t u8g_dev_rrd_st7920_128x64_fn(u8g_t *u8g, u8g_dev_t *dev, uint8_t msg, void *arg)