fix warning C6011

card.cpp

@@ -43,9 +43,10 @@ bool card::card_operation_sort(card* c1, card* c2) {
 	if(c1->current.location != c2->current.location)
 		return c1->current.location < c2->current.location;
 	if(c1->current.location & LOCATION_OVERLAY) {
-		if(c1->overlay_target->current.sequence != c2->overlay_target->current.sequence)
+		if(c1->overlay_target && c2->overlay_target && c1->overlay_target->current.sequence != c2->overlay_target->current.sequence)
 			return c1->overlay_target->current.sequence < c2->overlay_target->current.sequence;
-		else return c1->current.sequence < c2->current.sequence;
+		else
+			return c1->current.sequence < c2->current.sequence;
 	} else {
 		if(c1->current.location & (LOCATION_DECK | LOCATION_EXTRA | LOCATION_GRAVE | LOCATION_REMOVED))
 			return c1->current.sequence > c2->current.sequence;

ocgapi.cpp

@@ -265,7 +265,7 @@ extern "C" DECL_DLLEXPORT int32 query_field_card(ptr pduel, uint8 playerid, uint
 		}
 	}
 	else {
-		field::card_vector* lst = 0;
+		field::card_vector* lst = nullptr;
 		if(location == LOCATION_HAND)
 			lst = &player.list_hand;
 		else if(location == LOCATION_GRAVE)
@@ -276,6 +276,8 @@ extern "C" DECL_DLLEXPORT int32 query_field_card(ptr pduel, uint8 playerid, uint
 			lst = &player.list_extra;
 		else if(location == LOCATION_DECK)
 			lst = &player.list_main;
+		else
+			return 0;
 		for(auto& pcard : *lst) {
 			uint32 clen = pcard->get_infos(p, query_flag, use_cache);
 			p += clen;