system.insert wipes the string if item is an empty string

[ghost]

Description

This code currently works with --mm:refc, but with --mm:arc or ORC (default) it replaces all characters in the string with null bytes:

proc main = 
  var stuff = "hello"
  stuff.insert ""
  echo repr stuff
  echo stuff.len

main()

Nim Version

Nim Compiler Version 2.1.1 [Linux: amd64]
Compiled at 2024-01-17
Copyright (c) 2006-2024 by Andreas Rumpf

git hash: f46f26e79aada7195f4d83d8601f0d856520763d
active boot switches: -d:release

Current Output

"\0\0\0\0\0"
5

Expected Output

Either a runtime error when calling insert with an empty item, or fixing the bug so that the output becomes:

"hello"
5

Possible Solution

No response

Additional Information

No response

[ringabout]

Yeah, it needs to prevent self movement.