diff --git a/portable/MemMang/heap_4.c b/portable/MemMang/heap_4.c
index 50af15dfb..8d4f69246 100644
--- a/portable/MemMang/heap_4.c
+++ b/portable/MemMang/heap_4.c
@@ -90,7 +90,7 @@
 
 /* The application writer has already defined the array used for the RTOS
  * heap - probably so it can be placed in a special segment or address. */
-    extern uint8_t ucHeap[ configTOTAL_HEAP_SIZE ];
+    extern uint8_t ucHeap[ ];
 #else
     PRIVILEGED_DATA static uint8_t ucHeap[ configTOTAL_HEAP_SIZE ];
 #endif /* configAPPLICATION_ALLOCATED_HEAP */