diff --git a/res/buildings/castle-2.xml b/res/buildings/castle-2.xml
index f32b5f480..a54957415 100644
--- a/res/buildings/castle-2.xml
+++ b/res/buildings/castle-2.xml
@@ -1,5 +1,5 @@
 <?xml version="1.0"?>
-<building name="castle" capacity="1" fort="1">
+<building name="castle" capacity="1" fort="yes">
   <function name="name" value="castle_name_2"/>
   <function name="protection" value="building_protection"/>
   <function name="taxes" value="lua_building_taxes"/>
diff --git a/res/buildings/castle.xml b/res/buildings/castle.xml
index e4e295a71..9a63d7dc8 100644
--- a/res/buildings/castle.xml
+++ b/res/buildings/castle.xml
@@ -1,5 +1,5 @@
 <?xml version="1.0"?>
-<building name="castle" capacity="1" fort="1">
+<building name="castle" capacity="1" fort="yes">
   <function name="name" value="castle_name"/>
   <function name="protection" value="building_protection"/>
   <construction skill="building" minskill="1" maxsize="2" reqsize="1" defense_bonus="0">
diff --git a/res/core/de/strings.xml b/res/core/de/strings.xml
index 2188b225c..3186dcc42 100644
--- a/res/core/de/strings.xml
+++ b/res/core/de/strings.xml
@@ -246,6 +246,10 @@
       unharmed from every conflict, no enemy will lay hand on
       the bearer for one week.</text>
     </string>
+    <string name="skillpotion">
+        <text locale="en">The recipe of this potion is a well kept secret. Some even say it couldn't be brewed by mere mortals. One thing is certain though, the drinker receives further insight into any learned skills, which furthers their progress towards the mastery of those skills.</text>
+        <text locale="de">Die Herstellung dieses Trunkes ist ein wohlgehütetes Geheimnis. Manche behaupten gar, von Sterblichen könne er gar nicht gebraut werden. Tatsache ist, dass er dem Trinkenden tiefere Einsicht in seine erlernten Talente gewährt, was ihn in der Meisterung dieser Talente voranbringt.</text>
+    </string>
   </namespace>
 
   <namespace name="school">
@@ -3648,10 +3652,6 @@
       <text locale="en">For a healing potion one takes the peel of a windbag and some bugleweed, stirr in some chopped elvendear and sprinkle it with the blossoms of an ice begonia. This has to cook through for four days, while a gapgrowth has to be added on the second day. Then one carefully scoops off the top layer of liquid. One such potion gives four men (or one man four times) a 50% chance to survive otherwise lethal wounds. The potion is automatically used in case of injury.</text>
       <text locale="de">Für einen Heiltrank nehme man die Schale eines Windbeutels und etwas Gurgelkraut, rühre eine kleingehacktes Elfenlieb dazu und bestreue alles mit den Blüten einer Eisblume. Dies muß vier Tage lang gären, wobei man am zweiten Tag einen Spaltwachs dazutun muß. Dann ziehe man vorsichtig den oben schwimmenden Saft ab. Ein solcher Trank gibt vier Männern (oder einem Mann vier mal) im Kampf eine Chance von 50%, sonst tödliche Wunden zu überleben. Der Trank wird von ihnen automatisch bei Verletzung angewandt.</text>
     </string>
-    <string name="skillpotion">
-    	<text locale="en">The recipe of this potion is a well kept secret. Some even say it couldn't be brewed by mere mortals. One thing is certain though, the drinker receives further insight into any learned skills, which furthers their progress towards the mastery of those skills.</text>
-    	<text locale="de">Die Herstellung dieses Trunkes ist ein wohlgehütetes Geheimnis. Manche behaupten gar, von Sterblichen könne er gar nicht gebraut werden. Tatsache ist, dass er dem Trinkenden tiefere Einsicht in seine erlernten Talente gewährt, was ihn in der Meisterung dieser Talente voranbringt.</text>
-    </string>
   </namespace>
   <namespace name="spell">
     <string name="create_rop">
diff --git a/res/e3a/buildings.xml b/res/e3a/buildings.xml
index ef4ef4199..231596dc6 100644
--- a/res/e3a/buildings.xml
+++ b/res/e3a/buildings.xml
@@ -3,7 +3,7 @@
 
   <xi:include href="config://default/buildings/castle-2.xml" />
 
-  <building name="watch" capacity="1" maxsize="10" fort="1">
+  <building name="watch" capacity="1" maxsize="10" fort="yes">
     <function name="name" value="fort_name"/>
     <function name="protection" value="building_protection"/>
     <function name="taxes" value="lua_building_taxes"/>
diff --git a/s/coverity b/s/coverity
index 8a7748e31..0ade4a113 100755
--- a/s/coverity
+++ b/s/coverity
@@ -1,6 +1,7 @@
 #!/bin/bash
 set -e
 VERSION="$1"
+echo "submitting version $VERSION"
 shift
 DESC="$*"
 cd Debug
diff --git a/src/kernel/building.c b/src/kernel/building.c
index d4a7fbbbd..55005722e 100644
--- a/src/kernel/building.c
+++ b/src/kernel/building.c
@@ -666,7 +666,7 @@ void building_setregion(building * b, region * r)
 bool in_safe_building(unit *u1, unit *u2) {
     if (u1->building) {
         building * b = inside_building(u1);
-        if (b->type->flags & BTF_FORTIFICATION) {
+        if (b && b->type->flags & BTF_FORTIFICATION) {
             if (!u2->building) {
                 return true;
             }
diff --git a/src/kernel/building.test.c b/src/kernel/building.test.c
index 4241e893f..f3e66e34d 100644
--- a/src/kernel/building.test.c
+++ b/src/kernel/building.test.c
@@ -410,7 +410,9 @@ static void test_safe_building(CuTest *tc) {
     CuAssertIntEquals(tc, true, in_safe_building(u1, u2));
     u2->building = u1->building;
     CuAssertIntEquals(tc, true, in_safe_building(u1, u2));
-    u1->building->size = 2;
+    u1->number = 2;
+    CuAssertIntEquals(tc, false, in_safe_building(u1, u2));
+    u1->building->size = 3;
     CuAssertIntEquals(tc, false, in_safe_building(u1, u2));
     test_cleanup();
 }