diff --git a/lib/system/deepcopy.nim b/lib/system/deepcopy.nim
index 7a26a17c54..19accf304f 100644
--- a/lib/system/deepcopy.nim
+++ b/lib/system/deepcopy.nim
@@ -34,7 +34,7 @@ proc genericDeepCopyAux(dest, src: pointer, n: ptr TNimNode) {.benign.} =
 
 proc copyDeepString(src: NimString): NimString {.inline.} =
   if src != nil:
-    result = rawNewString(src.space)
+    result = rawNewStringNoInit(src.len)
     result.len = src.len
     c_memcpy(result.data, src.data, (src.len + 1) * sizeof(char))