Merge pull request #4398 from thinkyhead/rc_z_safe_sanity

Sanity checks for Z_SAFE_HOMING

Marlin/Conditionals.h

    */
   #define HAS_PROBING_PROCEDURE (ENABLED(AUTO_BED_LEVELING_FEATURE) || ENABLED(Z_MIN_PROBE_REPEATABILITY_TEST))
 
-  #if HAS_PROBING_PROCEDURE
-    // Boundaries for probing based on set limits
-    #define MIN_PROBE_X (max(X_MIN_POS, X_MIN_POS + X_PROBE_OFFSET_FROM_EXTRUDER))
-    #define MAX_PROBE_X (min(X_MAX_POS, X_MAX_POS + X_PROBE_OFFSET_FROM_EXTRUDER))
-    #define MIN_PROBE_Y (max(Y_MIN_POS, Y_MIN_POS + Y_PROBE_OFFSET_FROM_EXTRUDER))
-    #define MAX_PROBE_Y (min(Y_MAX_POS, Y_MAX_POS + Y_PROBE_OFFSET_FROM_EXTRUDER))
-  #endif
+  // Boundaries for probing based on set limits
+  #define MIN_PROBE_X (max(X_MIN_POS, X_MIN_POS + X_PROBE_OFFSET_FROM_EXTRUDER))
+  #define MAX_PROBE_X (min(X_MAX_POS, X_MAX_POS + X_PROBE_OFFSET_FROM_EXTRUDER))
+  #define MIN_PROBE_Y (max(Y_MIN_POS, Y_MIN_POS + Y_PROBE_OFFSET_FROM_EXTRUDER))
+  #define MAX_PROBE_Y (min(Y_MAX_POS, Y_MAX_POS + Y_PROBE_OFFSET_FROM_EXTRUDER))
 
   #define HAS_Z_SERVO_ENDSTOP (defined(Z_ENDSTOP_SERVO_NR) && Z_ENDSTOP_SERVO_NR >= 0)
 

Marlin/SanityCheck.h

     #error "AUTO_BED_LEVELING_FEATURE requires a probe! Define a Z Servo, Z_PROBE_ALLEN_KEY, Z_PROBE_SLED, or FIX_MOUNTED_PROBE."
   #elif ENABLED(Z_MIN_PROBE_REPEATABILITY_TEST)
     #error "Z_MIN_PROBE_REPEATABILITY_TEST requires a probe! Define a Z Servo, Z_PROBE_ALLEN_KEY, Z_PROBE_SLED, or FIX_MOUNTED_PROBE."
+  #elif ENABLED(Z_SAFE_HOMING)
+    #error "Z_SAFE_HOMING currently requires a probe."
   #endif
 
 #endif
 
 /**
+ * Make sure Z_SAFE_HOMING point is reachable
+ */
+#if ENABLED(Z_SAFE_HOMING)
+  #if Z_SAFE_HOMING_X_POINT < MIN_PROBE_X || Z_SAFE_HOMING_X_POINT > MAX_PROBE_X
+    #error "The given Z_SAFE_HOMING_X_POINT can't be reached by the Z probe."
+  #elif Z_SAFE_HOMING_Y_POINT < MIN_PROBE_Y || Z_SAFE_HOMING_Y_POINT > MAX_PROBE_Y
+    #error "The given Z_SAFE_HOMING_Y_POINT can't be reached by the Z probe."
+  #endif
+#endif // Z_SAFE_HOMING
+
+/**
  * Auto Bed Leveling
  */
 #if ENABLED(AUTO_BED_LEVELING_FEATURE)