Use C++ language supported 'nullptr' (#13944)

Marlin/src/module/configuration_store.cpp

@@ -2132,7 +2132,7 @@ void MarlinSettings::postprocess() {
       #endif
     }
 
-    void MarlinSettings::load_mesh(const int8_t slot, void * const into/*=NULL*/) {
+    void MarlinSettings::load_mesh(const int8_t slot, void * const into/*=nullptr*/) {
 
       #if ENABLED(AUTO_BED_LEVELING_UBL)
 
@@ -2545,7 +2545,7 @@ void MarlinSettings::reset() {
   #if HAS_TRINAMIC
     inline void say_M906(const bool forReplay) { CONFIG_ECHO_START(); SERIAL_ECHOPGM("  M906"); }
     #if HAS_STEALTHCHOP
-      void say_M569(const char * const etc=NULL) {
+      void say_M569(const char * const etc=nullptr) {
         SERIAL_ECHOPGM("  M569 S1");
         if (etc) {
           SERIAL_CHAR(' ');

Marlin/src/module/configuration_store.h

@@ -65,7 +65,7 @@ class MarlinSettings {
         static uint16_t calc_num_meshes();
         static int mesh_slot_offset(const int8_t slot);
         static void store_mesh(const int8_t slot);
-        static void load_mesh(const int8_t slot, void * const into=NULL);
+        static void load_mesh(const int8_t slot, void * const into=nullptr);
 
         //static void delete_mesh();    // necessary if we have a MAT
         //static void defrag_meshes();  // "

Marlin/src/module/endstops.cpp

@@ -377,7 +377,7 @@ void Endstops::event_handler() {
   prev_hit_state = hit_state;
 }
 
-static void print_es_state(const bool is_hit, PGM_P const label=NULL) {
+static void print_es_state(const bool is_hit, PGM_P const label=nullptr) {
   if (label) serialprintPGM(label);
   SERIAL_ECHOPGM(": ");
   serialprintPGM(is_hit ? PSTR(MSG_ENDSTOP_HIT) : PSTR(MSG_ENDSTOP_OPEN));

Marlin/src/module/planner.cpp

@@ -900,7 +900,7 @@ void Planner::reverse_pass() {
   // Reverse Pass: Coarsely maximize all possible deceleration curves back-planning from the last
   // block in buffer. Cease planning when the last optimal planned or tail pointer is reached.
   // NOTE: Forward pass will later refine and correct the reverse pass to create an optimal plan.
-  const block_t *next = NULL;
+  const block_t *next = nullptr;
   while (block_index != planned_block_index) {
 
     // Perform the reverse pass
@@ -995,7 +995,7 @@ void Planner::forward_pass() {
   uint8_t block_index = block_buffer_planned;
 
   block_t *current;
-  const block_t * previous = NULL;
+  const block_t * previous = nullptr;
   while (block_index != block_buffer_head) {
 
     // Perform the forward pass
@@ -1045,7 +1045,7 @@ void Planner::recalculate_trapezoids() {
   }
 
   // Go from the tail (currently executed block) to the first block, without including it)
-  block_t *current = NULL, *next = NULL;
+  block_t *current = nullptr, *next = nullptr;
   float current_entry_speed = 0.0, next_entry_speed = 0.0;
   while (block_index != head_block_index) {
 

Marlin/src/module/planner.h

@@ -746,7 +746,7 @@ class Planner {
     FORCE_INLINE static bool has_blocks_queued() { return (block_buffer_head != block_buffer_tail); }
 
     /**
-     * The current block. NULL if the buffer is empty.
+     * The current block. nullptr if the buffer is empty.
      * This also marks the block as busy.
      * WARNING: Called from Stepper ISR context!
      */
@@ -763,7 +763,7 @@ class Planner {
           --delay_before_delivering;
           // If the number of movements queued is less than 3, and there is still time
           //  to wait, do not deliver anything
-          if (nr_moves < 3 && delay_before_delivering) return NULL;
+          if (nr_moves < 3 && delay_before_delivering) return nullptr;
           delay_before_delivering = 0;
         }
 
@@ -771,7 +771,7 @@ class Planner {
         block_t * const block = &block_buffer[block_buffer_tail];
 
         // No trapezoid calculated? Don't execute yet.
-        if (TEST(block->flag, BLOCK_BIT_RECALCULATE)) return NULL;
+        if (TEST(block->flag, BLOCK_BIT_RECALCULATE)) return nullptr;
 
         #if ENABLED(ULTRA_LCD)
           block_buffer_runtime_us -= block->segment_time_us; // We can't be sure how long an active block will take, so don't count it.
@@ -793,7 +793,7 @@ class Planner {
         clear_block_buffer_runtime(); // paranoia. Buffer is empty now - so reset accumulated time to zero.
       #endif
 
-      return NULL;
+      return nullptr;
     }
 
     /**

Marlin/src/module/stepper.cpp

@@ -133,7 +133,7 @@ Stepper stepper; // Singleton
 
 // private:
 
-block_t* Stepper::current_block; // (= NULL) A pointer to the block currently being traced
+block_t* Stepper::current_block; // (= nullptr) A pointer to the block currently being traced
 
 uint8_t Stepper::last_direction_bits, // = 0
         Stepper::axis_did_move; // = 0
@@ -1394,7 +1394,7 @@ void Stepper::stepper_pulse_phase_isr() {
     abort_current_block = false;
     if (current_block) {
       axis_did_move = 0;
-      current_block = NULL;
+      current_block = nullptr;
       planner.discard_current_block();
     }
   }
@@ -1541,7 +1541,7 @@ uint32_t Stepper::stepper_block_phase_isr() {
         runout.block_completed(current_block);
       #endif
       axis_did_move = 0;
-      current_block = NULL;
+      current_block = nullptr;
       planner.discard_current_block();
     }
     else {

Marlin/src/module/temperature.cpp

@@ -1264,7 +1264,7 @@ void Temperature::manage_heater() {
       #if ENABLED(CHAMBER_USER_THERMISTOR)
         t_index == CTI_CHAMBER ? PSTR("CHAMBER") :
       #endif
-      NULL
+      nullptr
     );
     SERIAL_EOL();
   }

Marlin/src/module/thermistor/thermistors.h

@@ -147,7 +147,7 @@
 #elif defined(HEATER_0_USES_THERMISTOR)
   #error "No heater 0 thermistor table specified"
 #else
-  #define HEATER_0_TEMPTABLE NULL
+  #define HEATER_0_TEMPTABLE nullptr
   #define HEATER_0_TEMPTABLE_LEN 0
 #endif
 
@@ -157,7 +157,7 @@
 #elif defined(HEATER_1_USES_THERMISTOR)
   #error "No heater 1 thermistor table specified"
 #else
-  #define HEATER_1_TEMPTABLE NULL
+  #define HEATER_1_TEMPTABLE nullptr
   #define HEATER_1_TEMPTABLE_LEN 0
 #endif
 
@@ -167,7 +167,7 @@
 #elif defined(HEATER_2_USES_THERMISTOR)
   #error "No heater 2 thermistor table specified"
 #else
-  #define HEATER_2_TEMPTABLE NULL
+  #define HEATER_2_TEMPTABLE nullptr
   #define HEATER_2_TEMPTABLE_LEN 0
 #endif
 
@@ -177,7 +177,7 @@
 #elif defined(HEATER_3_USES_THERMISTOR)
   #error "No heater 3 thermistor table specified"
 #else
-  #define HEATER_3_TEMPTABLE NULL
+  #define HEATER_3_TEMPTABLE nullptr
   #define HEATER_3_TEMPTABLE_LEN 0
 #endif
 
@@ -187,7 +187,7 @@
 #elif defined(HEATER_4_USES_THERMISTOR)
   #error "No heater 4 thermistor table specified"
 #else
-  #define HEATER_4_TEMPTABLE NULL
+  #define HEATER_4_TEMPTABLE nullptr
   #define HEATER_4_TEMPTABLE_LEN 0
 #endif
 
@@ -197,7 +197,7 @@
 #elif defined(HEATER_5_USES_THERMISTOR)
   #error "No heater 5 thermistor table specified"
 #else
-  #define HEATER_5_TEMPTABLE NULL
+  #define HEATER_5_TEMPTABLE nullptr
   #define HEATER_5_TEMPTABLE_LEN 0
 #endif