diff --git a/include/display.h b/include/display.h
index 20c6cead6..ee4958905 100644
--- a/include/display.h
+++ b/include/display.h
@@ -157,7 +157,7 @@
  * definition here is convenient.  No longer limited to pets.
  */
 #define _is_safemon(mon) \
-    (flags.safe_dog && (mon) && (mon)->mpeaceful && canspotmon(mon)     \
+    (flags.safe_dog && (mon)->mpeaceful && canspotmon(mon)              \
      && !Confusion && !Hallucination && !Stunned)
 
 /*
diff --git a/src/hack.c b/src/hack.c
index 1f18b41fe..1c0f6c4fe 100644
--- a/src/hack.c
+++ b/src/hack.c
@@ -1768,6 +1768,7 @@ domove_attackmon_at(
     coordxy x, coordxy y,
     boolean *displaceu)
 {
+    /* assert(mtmp != NULL) */
     /* only attack if we know it's there
      * or if we used the 'F' command to fight blindly
      * or if it hides_under, in which case we call do_attack() to print