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[TiborB <tiborb95@xxxxxxxxx>]

GunChleoc - this is not about zero division but about out-of-range - I think.

Do you think that problem is that genstats is not populated some very short time after loading and AI tries to access members that are not there yet? So that genstats.size()==0? 

If this is the case I would use other aproach then try-catch...

Also see comments in diff, default decision for AI if it can not get data on military strength of enemy should be 'do not attack'




Diff comments:

> === modified file 'src/ai/defaultai.cc'
> --- src/ai/defaultai.cc	2014-10-31 20:49:02 +0000
> +++ src/ai/defaultai.cc	2014-11-01 14:10:33 +0000
> @@ -698,7 +698,7 @@
>  		}
>  	}
>  
> -	// folowing is done allways (regardless of military or not)
> +	// the following is done always (regardless of military or not)
>  
>  	// we get immovables with higher radius
>  	immovables.clear();
> @@ -710,6 +710,7 @@
>  	field.military_presence_ = 0;
>  
>  	for (uint32_t i = 0; i < immovables.size(); ++i) {
> +
>  		const BaseImmovable& base_immovable = *immovables.at(i).object;
>  
>  		// testing if it is enemy-owned field
> @@ -3089,20 +3090,27 @@
>  	const Game::GeneralStatsVector& genstats = game().get_general_statistics();
>  	for (uint8_t j = 1; j <= plr_in_game; ++j) {
>  		if (pn == j) {
> -			player_attackable[j - 1] = false;
> +			player_attackable.at(j - 1) = false;
>  			continue;
>  		}
>  
> -		if (genstats[j - 1].miltary_strength.back() == 0) {
> -			// to avoid improbable zero division
> -			player_attackable[j - 1] = true;
> -			any_attackable = true;
> -		} else if ((genstats[pn - 1].miltary_strength.back() * 100 /
> -		            genstats[j - 1].miltary_strength.back()) > treshold_ratio) {
> -			player_attackable[j - 1] = true;
> -			any_attackable = true;
> -		} else {
> -			player_attackable[j - 1] = false;
> +		try {
> +			// Avoid division by zero
> +			if (genstats.at(j - 1).miltary_strength.empty() ||
> +				 genstats.at(j - 1).miltary_strength.back() == 0) {
> +				player_attackable.at(j - 1) = true;
> +				any_attackable = true;
> +			// Check threshold
> +			} else if ((genstats.at(pn - 1).miltary_strength.back() * 100 /
> +							genstats.at(j - 1).miltary_strength.back()) > treshold_ratio) {
> +				player_attackable.at(j - 1) = true;
> +				any_attackable = true;
> +			} else {
> +				player_attackable.at(j - 1) = false;
> +			}
> +		} catch (const std::out_of_range&) {
> +			player_attackable.at(j - 1) = true;

change to false

> +			any_attackable = true;

remove the line

>  		}
>  	}
>  
> 


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