diff --git a/lib/system.nim b/lib/system.nim
index 00dd00bc09..687a68119a 100644
--- a/lib/system.nim
+++ b/lib/system.nim
@@ -1518,7 +1518,7 @@ proc delete*[T](x: var seq[T], i: Natural) {.noSideEffect.} =
   ##  i.delete(2) #=> @[1, 2, 4, 5]
   template defaultImpl =
     let xl = x.len
-    for j in i..xl-2: shallowCopy(x[j], x[j+1])
+    for j in i.int..xl-2: shallowCopy(x[j], x[j+1])
     setLen(x, xl-1)
 
   when nimvm:
diff --git a/tests/system/tsystem_misc.nim b/tests/system/tsystem_misc.nim
index 66b789ee96..ce36895a13 100644
--- a/tests/system/tsystem_misc.nim
+++ b/tests/system/tsystem_misc.nim
@@ -16,3 +16,7 @@ doAssert high(uint32) > low(uint32)
 doAssert high(float) > low(float)
 doAssert high(float32) > low(float32)
 doAssert high(float64) > low(float64)
+
+# bug #6710
+var s = @[1]
+s.delete(0)