diff --git a/drace-client/include/aligned-buffer.h b/drace-client/include/aligned-buffer.h
index 71b31a9..3948176 100644
--- a/drace-client/include/aligned-buffer.h
+++ b/drace-client/include/aligned-buffer.h
@@ -83,9 +83,14 @@ namespace drace {
 				// copy this as value is modified by std::align
 				size_t space_size = _size_in_bytes;
 				_mem = dr_thread_alloc(drcontext, _size_in_bytes);
-				data = (T*)std::align(alignment, capacity, _mem, space_size);
+                // std::align changes pointer to memspace, hence copy
+                void * mem_align = _mem;
+                DR_ASSERT_MSG(
+                    std::align(alignment, capacity, mem_align, space_size) != nullptr,
+                    "could not allocate aligned memory");
+                data = (T*)mem_align;
 				DR_ASSERT(((uint64_t)data % alignment) == 0);
 			}
 		}
 	};
-}
\ No newline at end of file
+}
diff --git a/drace-client/src/memory-tracker.cpp b/drace-client/src/memory-tracker.cpp
index c9f4d51..af01e0c 100644
--- a/drace-client/src/memory-tracker.cpp
+++ b/drace-client/src/memory-tracker.cpp
@@ -273,6 +273,8 @@ namespace drace {
         data->stack.deallocate(drcontext);
         data->mem_buf.deallocate(drcontext);
 
+        hashtable_delete(&(data->mutex_book));
+
         // free statistics
         data->stats->~Statistics();
         dr_thread_free(drcontext, data->stats, sizeof(Statistics));