diff --git a/src/mem/metaslab.h b/src/mem/metaslab.h
index f364ce6..f96ff76 100644
--- a/src/mem/metaslab.h
+++ b/src/mem/metaslab.h
@@ -33,7 +33,7 @@ namespace snmalloc
     /**
      *  Pointer to first free entry in this slab
      *
-     *  The list will (allocated - needed - 1) long. The -1 is
+     *  The list will be (allocated - needed - 1) long. The -1 is
      *  for the `link` element which is not in the free list.
      */
     void* head;
@@ -145,6 +145,11 @@ namespace snmalloc
       return pointer_cast<Slab>(address_cast(p) & SLAB_MASK);
     }
 
+    static bool is_short(Slab* p)
+    {
+      return (address_cast(p) & SUPERSLAB_MASK) == address_cast(p);
+    }
+
     /**
      * Check bump-free-list-segment for cycles
      *
@@ -187,9 +192,11 @@ namespace snmalloc
 #endif
     }
 
-    void debug_slab_invariant(bool is_short, Slab* slab)
+    void debug_slab_invariant(Slab* slab)
     {
 #if !defined(NDEBUG) && !defined(SNMALLOC_CHEAP_CHECKS)
+      bool is_short = Metaslab::is_short(slab);
+
       if (is_full())
       {
         // There is no free list to validate
@@ -252,7 +259,6 @@ namespace snmalloc
       assert(SLAB_SIZE == accounted_for);
 #else
       UNUSED(slab);
-      UNUSED(is_short);
 #endif
     }
   };
diff --git a/src/mem/slab.h b/src/mem/slab.h
index 4606a87..9234aa5 100644
--- a/src/mem/slab.h
+++ b/src/mem/slab.h
@@ -43,7 +43,7 @@ namespace snmalloc
       void* head = meta.head;
 
       assert(rsize == sizeclass_to_size(meta.sizeclass));
-      meta.debug_slab_invariant(is_short(), this);
+      meta.debug_slab_invariant(this);
       assert(sl.get_head() == (SlabLink*)((size_t)this + meta.link));
       assert(!meta.is_full());
 
@@ -127,7 +127,7 @@ namespace snmalloc
 
       assert(is_start_of_object(Superslab::get(p), p));
 
-      meta.debug_slab_invariant(is_short(), this);
+      meta.debug_slab_invariant(this);
 
       if constexpr (zero_mem == YesZero)
       {
@@ -158,7 +158,7 @@ namespace snmalloc
       if (meta.is_unused())
         error("Detected potential double free.");
 #endif
-      meta.debug_slab_invariant(is_short(), this);
+      meta.debug_slab_invariant(this);
 
       if (unlikely(meta.return_object()))
         return false;
@@ -172,7 +172,7 @@ namespace snmalloc
 
       // Set the next pointer to the previous head.
       Metaslab::store_next(p, head);
-      meta.debug_slab_invariant(is_short(), this);
+      meta.debug_slab_invariant(this);
       return true;
     }
 
@@ -206,7 +206,7 @@ namespace snmalloc
 
         // Push on the list of slabs for this sizeclass.
         sl->insert_back(meta.get_link(this));
-        meta.debug_slab_invariant(is_short(), this);
+        meta.debug_slab_invariant(this);
         return Superslab::NoSlabReturn;
       }
 
@@ -218,10 +218,9 @@ namespace snmalloc
 
       return super->dealloc_slab(this, memory_provider);
     }
-
     bool is_short()
     {
-      return (address_cast(this) & SUPERSLAB_MASK) == address_cast(this);
+      return Metaslab::is_short(this);
     }
   };
 } // namespace snmalloc