Add JOIN for simple append

Marlin/src/core/macros.h

 #define LIST_N(N,V...) _LIST_N(N,V)
 #define ARRAY_N(N,V...) { _LIST_N(N,V) }
 
+#define _JOIN_1(O)         (O)
+#define JOIN_N(N,C,V...)   (DO(JOIN,C,LIST_N(N,V)))
+
 // Macros for adding
 #define INC_0 1
 #define INC_1 2

Marlin/src/lcd/menu/menu_filament.cpp

             SUBMENU(MSG_FILAMENTUNLOAD, menu_temp_e0_filament_unload);
         #else
           #if ENABLED(FILAMENT_UNLOAD_ALL_EXTRUDERS)
-            if (thermalManager.targetHotEnoughToExtrude(0)
-              #if E_STEPPERS > 1
-                && thermalManager.targetHotEnoughToExtrude(1)
-                #if E_STEPPERS > 2
-                  && thermalManager.targetHotEnoughToExtrude(2)
-                  #if E_STEPPERS > 3
-                    && thermalManager.targetHotEnoughToExtrude(3)
-                    #if E_STEPPERS > 4
-                      && thermalManager.targetHotEnoughToExtrude(4)
-                      #if E_STEPPERS > 5
-                        && thermalManager.targetHotEnoughToExtrude(5)
-                      #endif // E_STEPPERS > 5
-                    #endif // E_STEPPERS > 4
-                  #endif // E_STEPPERS > 3
-                #endif // E_STEPPERS > 2
-              #endif // E_STEPPERS > 1
-            )
-              GCODES_ITEM(MSG_FILAMENTUNLOAD_ALL, PSTR("M702"));
+            if (JOIN_N(E_STEPPERS, &&,
+              thermalManager.targetHotEnoughToExtrude(0),
+              thermalManager.targetHotEnoughToExtrude(1),
+              thermalManager.targetHotEnoughToExtrude(2),
+              thermalManager.targetHotEnoughToExtrude(3),
+              thermalManager.targetHotEnoughToExtrude(4),
+              thermalManager.targetHotEnoughToExtrude(5))
+            ) GCODES_ITEM(MSG_FILAMENTUNLOAD_ALL, PSTR("M702"));
           else
             SUBMENU(MSG_FILAMENTUNLOAD_ALL, menu_unload_filament_all_temp);
           #endif

buildroot/share/tests/megaatmega2560-tests

            EEPROM_SETTINGS SDSUPPORT SD_REPRINT_LAST_SELECTED_FILE BINARY_FILE_TRANSFER \
            BLINKM PCA9632 RGB_LED RGB_LED_R_PIN RGB_LED_G_PIN RGB_LED_B_PIN LED_CONTROL_MENU \
            NEOPIXEL_LED CASE_LIGHT_ENABLE CASE_LIGHT_USE_NEOPIXEL CASE_LIGHT_MENU \
-           NOZZLE_PARK_FEATURE ADVANCED_PAUSE_FEATURE FILAMENT_RUNOUT_DISTANCE_MM FILAMENT_RUNOUT_SENSOR \
-           AUTO_BED_LEVELING_BILINEAR Z_MIN_PROBE_REPEATABILITY_TEST DEBUG_LEVELING_FEATURE \
+           PID_PARAMS_PER_HOTEND PID_AUTOTUNE_MENU PID_EDIT_MENU \
+           NOZZLE_PARK_FEATURE FILAMENT_RUNOUT_SENSOR FILAMENT_RUNOUT_DISTANCE_MM \
+           ADVANCED_PAUSE_FEATURE FILAMENT_LOAD_UNLOAD_GCODES FILAMENT_UNLOAD_ALL_EXTRUDERS \
+           AUTO_BED_LEVELING_BILINEAR Z_MIN_PROBE_REPEATABILITY_TEST \
            SKEW_CORRECTION SKEW_CORRECTION_FOR_Z SKEW_CORRECTION_GCODE \
            BACKLASH_COMPENSATION BACKLASH_GCODE BAUD_RATE_GCODE BEZIER_CURVE_SUPPORT \
            FWRETRACT ARC_P_CIRCLES CNC_WORKSPACE_PLANES CNC_COORDINATE_SYSTEMS \
            PSU_CONTROL AUTO_POWER_CONTROL POWER_LOSS_RECOVERY POWER_LOSS_PIN POWER_LOSS_STATE \
-           SLOW_PWM_HEATERS THERMAL_PROTECTION_CHAMBER \
+           SLOW_PWM_HEATERS THERMAL_PROTECTION_CHAMBER LIN_ADVANCE \
            PINS_DEBUGGING MAX7219_DEBUG M114_DETAIL
 opt_set TEMP_SENSOR_CHAMBER 3
 opt_set HEATER_CHAMBER_PIN 45
-exec_test $1 $2 "RAMPS with 2 extruders, RepRap LCD, Linear ABL, LEDs, and many options"
+exec_test $1 $2 "RAMPS, 2 extruders, LCD/SD, Probe, ABL-Linear, PLR, LEDs, many options"
 
 #
 # Test a probeless build of AUTO_BED_LEVELING_UBL, with lots of extruders

buildroot/share/tests/teensy31-tests

 exec_test $1 $2 "Teensy3.1 with default config"
 
 #
-# Test as many features together as possible
+# Test many features together
 #
 restore_configs
 opt_set MOTHERBOARD BOARD_TEENSY31_32
 opt_set TEMP_SENSOR_0 1
 opt_set TEMP_SENSOR_BED 1
 opt_enable EEPROM_SETTINGS FILAMENT_WIDTH_SENSOR CALIBRATION_GCODE BAUD_RATE_GCODE \
-           FIX_MOUNTED_PROBE Z_SAFE_HOMING AUTO_BED_LEVELING_BILINEAR Z_MIN_PROBE_REPEATABILITY_TEST DEBUG_LEVELING_FEATURE \
+           FIX_MOUNTED_PROBE Z_SAFE_HOMING AUTO_BED_LEVELING_BILINEAR DEBUG_LEVELING_FEATURE Z_MIN_PROBE_REPEATABILITY_TEST \
            BABYSTEPPING BABYSTEP_XY BABYSTEP_ZPROBE_OFFSET PRINTCOUNTER SLOW_PWM_HEATERS PIDTEMPBED \
            INCH_MODE_SUPPORT TEMPERATURE_UNITS_SUPPORT M100_FREE_MEMORY_WATCHER \
            NOZZLE_PARK_FEATURE NOZZLE_CLEAN_FEATURE PARK_HEAD_ON_PAUSE \