fix: remove unused variable when dynamically sized at end

contracts/staking/Unpack.sol

@@ -40,7 +40,6 @@ library Unpack {
             let dynLength := sub(length, 84)
             v5 := add(input, 84)
             mstore(v5, dynLength)
-            let end := add(input, add(length, 0x20))
         }
     }
 
@@ -137,7 +136,6 @@ library Unpack {
             let dynLength := sub(length, 80)
             v4 := add(input, 80)
             mstore(v4, dynLength)
-            let end := add(input, add(length, 0x20))
         }
     }
 }

utils/unpack/Unpack.sol.gotmpl

@@ -54,7 +54,9 @@ library Unpack {
             v{{$i}} := add(input, {{.Offset}})
             mstore(v{{$i}}, dynLength)
                 {{- end}}
+                {{- if not ($unpacker.IsLastVar $i)}}
             let end := add(input, add(length, 0x20))
+                {{- end}}
             {{- else}}
                 {{- if .Front}}
             v{{$i}} := mload(add(input, {{.OffsetHex}}))

utils/unpack/unpack.go

@@ -222,6 +222,10 @@ func (u *unpacker) FuncNameSuffix() string {
 	return fmt.Sprintf("%s_Destructive", base)
 }
 
+func (u *unpacker) IsLastVar(i int) bool {
+	return i >= len(u.Vars)-1
+}
+
 // varPrefix is the prefix of all numerically identified variables in the
 // generated code; i.e. for prefix v, the variables are v0, v1, v2...
 const varPrefix = "v"