diff --git a/src/p_local.h b/src/p_local.h
index e1e248b6b..419b5b0f0 100644
--- a/src/p_local.h
+++ b/src/p_local.h
@@ -274,7 +274,7 @@ class FBlockThingsIterator
 	int NumFixedHash;
 	TArray<HashEntry> DynHash;
 
-	HashEntry *GetHashEntry(int i) { return i < countof(FixedHash) ? &FixedHash[i] : &DynHash[i - countof(FixedHash)]; }
+	HashEntry *GetHashEntry(int i) { return i < (int)countof(FixedHash) ? &FixedHash[i] : &DynHash[i - countof(FixedHash)]; }
 
 	void StartBlock(int x, int y);
 	void SwitchBlock(int x, int y);