Panic on startup: index out of bounds in src/ui_model/mod.rs

I'm using rust stable. I can't reproduce this reliably, but for some reason, it crashes on startup, both with and without a file argument.

Name	Details
Neovim version	Development version, from commit https://github.com/neovim/neovim/commit/43d32762e3aca2bf5656e0a928ac151f4702d93b
`rustup --version`	1.6.0 (a11c01e8c 2017-08-30)
`cargo --version`	0.21.0 (5b4b82ae 2017-08-12)
`rustc --version`	1.20.0 (fd3d6973f4 2017-08-27)
Operating system	Arch Linux

https://github.com/daa84/neovim-gtk/blob/0f4234a622d01b79fac4afd94e6561a15c68e1e8/src/ui_model/mod.rs#L76:25

Here's the backtrace. I installed it from the AUR, so that might explain why it's not showing other source code (it's not running from the same path it was built in):

thread 'main' panicked at 'index out of bounds: the len is 1 but the index is 1', src/ui_model/mod.rs:76:25
stack backtrace:
   0: <unknown>
   1: <unknown>
   2: <unknown>
   3: <unknown>
   4: <unknown>
   5: <unknown>
   6: <unknown>
   7: <unknown>
   8: <unknown>
   9: <unknown>
  10: <unknown>
  11: <unknown>
  12: <unknown>
  13: g_main_context_dispatch
  14: <unknown>
  15: g_main_context_iteration
  16: g_application_run
  17: <unknown>
  18: <unknown>
  19: <unknown>
  20: __libc_start_main
  21: <unknown>

EDIT: add neovim version

daa84 / neovim-gtk

Panic on startup: index out of bounds in src/ui_model/mod.rs #17