1 files changed, 13 insertions, 7 deletions

diff --git a/src/core/templates.h b/src/core/templates.h
index 9f5bd5ea..bb89814e 100644
--- a/src/core/templates.h
+++ b/src/core/templates.h
@@ -123,13 +123,19 @@ public:
 		return m_flags[handle>>8].u == (handle & 0xFF) ?
 		       (T*)&m_entries[handle >> 8] : nil;
 	}
-	int GetIndex(T *entry){
-		int i = GetJustIndex(entry);
-		return m_flags[i].u + (i<<8);
-	}
-	int GetJustIndex(T *entry){
-		// TODO: the cast is unsafe
-		return (int)((U*)entry - m_entries);
+	int GetIndex(T* entry) {
+		int i = GetJustIndex_NoFreeAssert(entry);
+		return m_flags[i].u + (i << 8);
+	}
+	int GetJustIndex(T* entry) {
+		int index = GetJustIndex_NoFreeAssert(entry);
+		assert(!IsFreeSlot(index));
+		return index;
+	}
+	int GetJustIndex_NoFreeAssert(T* entry) {
+		int index = ((U*)entry - m_entries);
+		assert((U*)entry == (U*)&m_entries[index]); // cast is unsafe - check required
+		return index;
 	}
 	int GetNoOfUsedSpaces(void) const {
 		int i;