NULL pointer to instance

[AXEL777 2]

I am view this in script.log:

SCRIPT    (E): NULL pointer to instance
Function: 'Get_State_For_Item'
Stack trace:
$CurrentDir:mpmissions/dayzOffline.chernarusplus/EnScript/Functions_Fixed.c:2036
$CurrentDir:mpmissions/dayzOffline.chernarusplus/EnScript/Functions_Fixed.c:2136
$CurrentDir:mpmissions/dayzOffline.chernarusplus/EnScript/Functions_Fixed.c:1948
$CurrentDir:mpmissions/dayzOffline.chernarusplus/EnScript/Functions_Fixed.c:2210
$CurrentDir:mpmissions/dayzOffline.chernarusplus/EnScript/Functions_Fixed.c:2191

what this is and how fix this?

I am use functions:

void Get_State_For_Item()
{
	... code ...
}

in init.c mpmission. What is wrong???

Edited December 16, 2018 by AXEL777

[colinm9991 196]

What's the code?

[AXEL777 2]

1 hour ago, colinm9991 said:

What's the code?

in this method:

static string Get_State_For_Item(ItemBase item)
{
	string return_stage_value = "";
	Edible_Base item_to_Edible_Base = Edible_Base.Cast(item);	
	if ((item_to_Edible_Base.IsMeat()) && (item_to_Edible_Base))
	{
		private string temp_ret_zn = "";
		temp_ret_zn = item_to_Edible_Base.GetFoodStageName(item_to_Edible_Base.GetFoodStageType());
		if (temp_ret_zn != "")
		{			
			return_stage_value = temp_ret_zn;
		}
	}
	return return_stage_value;
}

 

[colinm9991 196]

Swap around the if statement conditions, your logic currently says

IF item_to_Edible_Base is Meat AND item_to_Edible_Base is Not Null

Which has the possibility of checking if a null item IsMeat first before validating that it's actually a valid object.

 

You should first check for null, then if IsMeat, as the && will short-circuit the statement if the first condition is false.

 

See if the issue occurs after that, you could also put diagnostic logging in to see how far the script gets in its execution.

 

Is there a stack trace included in the log which you have omitted, or is it purposely blank?

Edited December 16, 2018 by colinm9991

[AXEL777 2]

3 minutes ago, colinm9991 said:

Swap around the if statement conditions, your logic currently says

IF item_to_Edible_Base is Meat AND item_to_Edible_Base is Not Null

Which has the possibility of checking if a null item IsMeat first before validating that it's actually a valid object.

 

You should first check for null, then if IsMeat, as the && will short-circuit the statement if the first condition is false.

 

See if the issue occurs after that, you could also put diagnostic logging in to see how far the script gets in its execution.

 

Is there a stack trace included in the log which you have omitted, or is it purposely blank?

yes, stack trace exist

SCRIPT    (E): NULL pointer to instance
Function: 'Get_State_For_Item'
Stack trace:
$CurrentDir:mpmissions/dayzOffline.chernarusplus/EnScript/Functions_Fixed.c:2036
$CurrentDir:mpmissions/dayzOffline.chernarusplus/EnScript/Functions_Fixed.c:2136
$CurrentDir:mpmissions/dayzOffline.chernarusplus/EnScript/Functions_Fixed.c:1948
$CurrentDir:mpmissions/dayzOffline.chernarusplus/EnScript/Functions_Fixed.c:2210
$CurrentDir:mpmissions/dayzOffline.chernarusplus/EnScript/Functions_Fixed.c:2191

 

Edited December 16, 2018 by AXEL777

[colinm9991 196]

4 minutes ago, AXEL777 said:

yes, stack trace exist

Can you update the post with it?

 

We can't debug/help if we don't have enough information about the event.

 

-- Edit:

 

Try the above recommendation please with changes to your script, I can see the stack trace isn't very helpful

Edited December 16, 2018 by colinm9991

[AXEL777 2]

11 minutes ago, colinm9991 said:

Can you update the post with it?

 

yes, updated

[AXEL777 2]

4 hours ago, colinm9991 said:

 

Try the above recommendation please with changes to your script, I can see the stack trace isn't very helpful

yes, this work, big thanks