message: Pin rust nightly version
diff: language: rust
  rust:
  - - nightly
  + - nightly-2019-08-25
  os:
  - linux
  -dist: bionic
  +dist: xenial
  sudo: false
  @@ -18,7 +18,7 @@ addons:
  apt:
  sources:
  - ubuntu-toolchain-r-test
  - - llvm-toolchain-bionic
  + - llvm-toolchain-xenial
  packages:
  - g++
  - llvm-dev
  