message: Remove pre_release in version info.
  This field is no longer being used, as pre-release versions have
  not been used in cargo for quite some time, and I don't anticipate
  them ever returning.
diff: @@ -22,7 +22,6 @@ pub struct VersionInfo {
  pub major: u8,
  pub minor: u8,
  pub patch: u8,
  - pub pre_release: Option<String>,
  /// Information that's only available when we were built with
  /// rustbuild, rather than Cargo itself.
  pub cfg_info: Option<CfgInfo>,
  @@ -34,8 +33,6 @@ impl fmt::Display for VersionInfo {
  if let Some(channel) = self.cfg_info.as_ref().map(|ci| &ci.release_channel) {
  if channel != "stable" {
  write!(f, "-{}", channel)?;
  - let empty = String::new();
  - write!(f, "{}", self.pre_release.as_ref().unwrap_or(&empty))?;
  }
  };
  @@ -86,7 +83,6 @@ pub fn version() -> VersionInfo {
  major,
  minor,
  patch,
  - pre_release: option_env_str!("CARGO_PKG_VERSION_PRE"),
  cfg_info: Some(CfgInfo {
  release_channel: option_env_str!("CFG_RELEASE_CHANNEL").unwrap(),
  commit_info,
  @@ -98,7 +94,6 @@ pub fn version() -> VersionInfo {
  major,
  minor,
  patch,
  - pre_release: option_env_str!("CARGO_PKG_VERSION_PRE"),
  cfg_info: None,
  },
  }
  