compiletest: crashes: turn off backtraces for faster tests

Author: matthiaskrgr

src/tools/compiletest/src/header.rs

@@ -581,6 +581,16 @@ impl TestProps {
 self.incremental = true;
 }
 
+if config.mode == Mode::Crashes{
+// we don't want to pollute anything with backtrace-files
+// also turn off backtraces in order to save some execution
+// time on the tests; we only need to know IF it crashes
+self.rustc_env = vec![
+("RUST_BACKTRACE".to_string(),"0".to_string()),
+("RUSTC_ICE".to_string(),"0".to_string()),
+];
+}
+
 for key in&["RUST_TEST_NOCAPTURE","RUST_TEST_THREADS"]{
 ifletOk(val) = env::var(key){
 ifself.exec_env.iter().find(|&&(ref x, _)| x == key).is_none(){
@@ -596,7 +606,8 @@ impl TestProps {
 
 fnupdate_fail_mode(&mutself,ln:&str,config:&Config){
 let check_ui = |mode:&str| {
-if config.mode != Mode::Ui{
+// Mode::Crashes may need build-fail in order to trigger llvm errors or stack overflows
+if config.mode != Mode::Ui && config.mode != Mode::Crashes{
 panic!("`{}-fail` header is only supported in UI tests", mode);
 }
 };
@@ -625,7 +636,7 @@ impl TestProps {
 fnupdate_pass_mode(&mutself,ln:&str,revision:Option<&str>,config:&Config){
 let check_no_run = |s| match(config.mode, s){
 (Mode::Ui, _) => (),
-(Mode::Crashes,"should-ice") => (),
+(Mode::Crashes,_) => (),
 (Mode::Codegen,"build-pass") => (),
 (Mode::Incremental, _) => {
 if revision.is_some() && !self.revisions.iter().all(|r| r.starts_with("cfail")){