The joystick instance ID is already set in the open call

src/joystick/android/SDL_sysjoystick.c

@@ -572,7 +572,6 @@ static int ANDROID_JoystickOpen(SDL_Joystick *joystick, int device_index)
         return SDL_SetError("Joystick already opened");
     }
 
-    joystick->instance_id = item->device_instance;
     joystick->hwdata = (struct joystick_hwdata *)item;
     item->joystick = joystick;
     joystick->nhats = item->nhats;

src/joystick/apple/SDL_mfijoystick.m

@@ -948,7 +948,6 @@ static int IOS_JoystickOpen(SDL_Joystick *joystick, int device_index)
     }
 
     joystick->hwdata = device;
-    joystick->instance_id = device->instance_id;
 
     joystick->naxes = device->naxes;
     joystick->nhats = device->nhats;

src/joystick/bsd/SDL_bsdjoystick.c

@@ -595,7 +595,6 @@ static int BSD_JoystickOpen(SDL_Joystick *joy, int device_index)
         return -1;
     }
 
-    joy->instance_id = item->device_instance;
     joy->hwdata = hw;
     joy->naxes = hw->naxes;
     joy->nbuttons = hw->nbuttons;

src/joystick/darwin/SDL_iokitjoystick.c

@@ -765,7 +765,6 @@ static int DARWIN_JoystickOpen(SDL_Joystick *joystick, int device_index)
 {
     recDevice *device = GetDeviceForIndex(device_index);
 
-    joystick->instance_id = device->instance_id;
     joystick->hwdata = device;
     device->joystick = joystick;
     joystick->name = device->product;

src/joystick/emscripten/SDL_sysjoystick.c

@@ -311,7 +311,6 @@ static int EMSCRIPTEN_JoystickOpen(SDL_Joystick *joystick, int device_index)
         return SDL_SetError("Joystick already opened");
     }
 
-    joystick->instance_id = item->device_instance;
     joystick->hwdata = (struct joystick_hwdata *)item;
     item->joystick = joystick;
 

src/joystick/haiku/SDL_haikujoystick.cc

@@ -139,7 +139,6 @@ extern "C"
         BJoystick *stick;
 
         /* Create the joystick data structure */
-        joystick->instance_id = device_index;
         joystick->hwdata = (struct joystick_hwdata *) SDL_calloc(1, sizeof(*joystick->hwdata));
         if (joystick->hwdata == NULL) {
             return -1;

src/joystick/linux/SDL_sysjoystick.c

@@ -1593,7 +1593,6 @@ static int LINUX_JoystickOpen(SDL_Joystick *joystick, int device_index)
         return SDL_SetError("No such device");
     }
 
-    joystick->instance_id = item->device_instance;
     joystick->hwdata = (struct joystick_hwdata *)
         SDL_calloc(1, sizeof(*joystick->hwdata));
     if (!joystick->hwdata) {

src/joystick/n3ds/SDL_sysjoystick.c

@@ -91,7 +91,6 @@ static int N3DS_JoystickOpen(SDL_Joystick *joystick, int device_index)
     joystick->nbuttons = NB_BUTTONS;
     joystick->naxes = 4;
     joystick->nhats = 0;
-    joystick->instance_id = device_index;
 
     return 0;
 }

src/joystick/ps2/SDL_sysjoystick.c

@@ -214,7 +214,6 @@ static int PS2_JoystickOpen(SDL_Joystick *joystick, int device_index)
     joystick->nbuttons = PS2_BUTTONS;
     joystick->naxes = PS2_TOTAL_AXIS;
     joystick->nhats = 0;
-    joystick->instance_id = device_index;
 
     SDL_SetBooleanProperty(SDL_GetJoystickProperties(joystick), SDL_PROP_JOYSTICK_CAP_RUMBLE_BOOLEAN, SDL_TRUE);
 

src/joystick/psp/SDL_sysjoystick.c

@@ -164,7 +164,6 @@ static int PSP_JoystickOpen(SDL_Joystick *joystick, int device_index)
     joystick->nbuttons = SDL_arraysize(button_map);
     joystick->naxes = 2;
     joystick->nhats = 0;
-    joystick->instance_id = device_index;
 
     return 0;
 }

src/joystick/virtual/SDL_virtualjoystick.c

@@ -422,7 +422,6 @@ static int VIRTUAL_JoystickOpen(SDL_Joystick *joystick, int device_index)
     if (!hwdata) {
         return SDL_SetError("No such device");
     }
-    joystick->instance_id = hwdata->instance_id;
     joystick->hwdata = hwdata;
     joystick->naxes = hwdata->desc.naxes;
     joystick->nbuttons = hwdata->desc.nbuttons;

src/joystick/vita/SDL_sysjoystick.c

@@ -211,7 +211,6 @@ static int VITA_JoystickOpen(SDL_Joystick *joystick, int device_index)
     joystick->nbuttons = SDL_arraysize(ext_button_map);
     joystick->naxes = 6;
     joystick->nhats = 0;
-    joystick->instance_id = device_index;
 
     SDL_SetBooleanProperty(SDL_GetJoystickProperties(joystick), SDL_PROP_JOYSTICK_CAP_RGB_LED_BOOLEAN, SDL_TRUE);
     SDL_SetBooleanProperty(SDL_GetJoystickProperties(joystick), SDL_PROP_JOYSTICK_CAP_RUMBLE_BOOLEAN, SDL_TRUE);