diff --git a/src/snmalloc/backend/backend.h b/src/snmalloc/backend/backend.h
index 1463fa9..5db5841 100644
--- a/src/snmalloc/backend/backend.h
+++ b/src/snmalloc/backend/backend.h
@@ -97,14 +97,13 @@ namespace snmalloc
 #ifdef SNMALLOC_TRACING
         message<1024>("Out of memory");
 #endif
-        return {p, nullptr};
+        return {nullptr, nullptr};
       }
 
       typename Pagemap::Entry t(meta, ras);
       Pagemap::set_metaentry(address_cast(p), size, t);
 
-      p = Aal::capptr_bound<void, capptr::bounds::Chunk>(p, size);
-      return {p, meta};
+      return {Aal::capptr_bound<void, capptr::bounds::Chunk>(p, size), meta};
     }
 
     /**
diff --git a/src/snmalloc/backend_helpers/range_helpers.h b/src/snmalloc/backend_helpers/range_helpers.h
index 90ee847..454cba0 100644
--- a/src/snmalloc/backend_helpers/range_helpers.h
+++ b/src/snmalloc/backend_helpers/range_helpers.h
@@ -4,8 +4,11 @@
 
 namespace snmalloc
 {
-  template<size_t MIN_BITS, typename F>
-  void range_to_pow_2_blocks(capptr::Chunk<void> base, size_t length, F f)
+  template<
+    size_t MIN_BITS,
+    SNMALLOC_CONCEPT(capptr::ConceptBound) B,
+    typename F>
+  void range_to_pow_2_blocks(CapPtr<void, B> base, size_t length, F f)
   {
     auto end = pointer_offset(base, length);
     base = pointer_align_up(base, bits::one_at_bit(MIN_BITS));