Use Clippy version in ICE message

Author: phansch

src/driver.rs

@@ -257,10 +257,12 @@ fn report_clippy_ice(info: &panic::PanicInfo<'_>, bug_report_url: &str) {
         handler.abort_if_errors_and_should_abort();
     }
 
+    let version_info = rustc_tools_util::get_version_info!();
+
     let xs: Vec<Cow<'static, str>> = vec![
         "the compiler unexpectedly panicked. this is a bug.".into(),
         format!("we would appreciate a bug report: {}", bug_report_url).into(),
-        format!("rustc {}", option_env!("CFG_VERSION").unwrap_or("unknown_version")).into(),
+        format!("Clippy version: {}", version_info).into(),
     ];
 
     for note in &xs {

tests/ui/custom_ice_message.stderr

@@ -7,5 +7,5 @@ note: the compiler unexpectedly panicked. this is a bug.
 
 note: we would appreciate a bug report: https://github.com/rust-lang/rust-clippy/issues/new
 
-note: rustc unknown_version
+note: Clippy version: clippy 0.0.212 (68ff8b19 2019-09-26)