diff --git a/src/gc/include/private/gcconfig.h b/src/gc/include/private/gcconfig.h
index 5f897a43c..93c118099 100644
--- a/src/gc/include/private/gcconfig.h
+++ b/src/gc/include/private/gcconfig.h
@@ -1470,8 +1470,8 @@
 #    define OS_TYPE "NONSTOP"
 #    define ALIGNMENT 4
 #    define DATASTART ((ptr_t) 0x08000000)
-     extern int _end[];
-#    define DATAEND (_end)
+     extern char **environ;
+#    define DATAEND ((ptr_t)(environ - 0x10))
 #    define STACKBOTTOM ((ptr_t) 0x4fffffff)
 #    define USE_GENERIC_PUSH_REGS
 #   endif