regression tests for ICEs

[venkatagiri]

closes#36379
closes#37550
closes#37665
closes#38160
closes#38954
closes#39362

r? @Mark-Simulacrum

[rust-highfive]

Thanks for the pull request, and welcome! The Rust team is excited to review your changes, and you should hear from @Mark-Simulacrum (or someone else) soon.

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[Mark-Simulacrum]

I believe this test needs to have --unpretty mir -Z unstable-options passed to the compiler. // compile-flags: -Z unstable-options --unpretty=mir should work at the top of the file.

[venkatagiri]

Done.

[Mark-Simulacrum]

Hm, looks like this won't quite work since (I believe) we don't actually reach the phase of the compiler where this errors out. Could you add a let x: () = 0; line with //~ ERROR: mismatched types attached to it and remove the rustc_error?

[venkatagiri]

Thanks for the tip. Am getting the error locally now, with & without the mir option.
Have pushed the fix.

[Mark-Simulacrum]

Thanks!

@bors r+ rollup

[bors]

📌 Commit c4570a7 has been approved by Mark-Simulacrum

[Mark-Simulacrum]

@bors r-

Travis failed

[venkatagiri]

The --unpretty=mir option is affecting the error being thrown.
With this option, the compilation is succeeding. Even though #[rustc_error] is added.
Removing the mir option, the compilation is failing as expected.

$ build/x86_64-unknown-linux-gnu/stage2/bin/rustc src/test/compile-fail/issue-37665.rs \
-L build/x86_64-unknown-linux-gnu/test/compile-fail --target=x86_64-unknown-linux-gnu --error-format json \
-L build/x86_64-unknown-linux-gnu/test/compile-fail/issue-37665.stage2-x86_64-unknown-linux-gnu.compile-fail.libaux \
-C prefer-dynamic -o build/x86_64-unknown-linux-gnu/test/compile-fail/issue-37665.stage2-x86_64-unknown-linux-gnu \
-Crpath -O -Lnative=build/x86_64-unknown-linux-gnu/native/rust-test-helpers -Z unstable-options --unpretty=mir
$ echo$?
0
$ build/x86_64-unknown-linux-gnu/stage2/bin/rustc src/test/compile-fail/issue-37665.rs \
-L build/x86_64-unknown-linux-gnu/test/compile-fail --target=x86_64-unknown-linux-gnu --error-format json \
-L build/x86_64-unknown-linux-gnu/test/compile-fail/issue-37665.stage2-x86_64-unknown-linux-gnu.compile-fail.libaux \
-C prefer-dynamic -o build/x86_64-unknown-linux-gnu/test/compile-fail/issue-37665.stage2-x86_64-unknown-linux-gnu \
-Crpath -O -Lnative=build/x86_64-unknown-linux-gnu/native/rust-test-helpers -Z unstable-options
{"message":"compilation successful","code":null,"level":"error","spans":[{"file_name":"src/test/compile-fail/issue-37665.rs","byte_start":594,"byte_end":743,"line_start":18,"line_end":22,"column_start":1,"column_end":2,"is_primary":true,"text":[{"text":"fn main() { //~ ERROR compilation successful","highlight_start":1,"highlight_end":45},{"text":" let mut foo : String = \"hello\".to_string();","highlight_start":1,"highlight_end":48},{"text":" foo.push(MAIN_SEPARATOR);","highlight_start":1,"highlight_end":30},{"text":" println!(\"{}\", foo);","highlight_start":1,"highlight_end":25},{"text":"}","highlight_start":1,"highlight_end":2}],"label":null,"suggested_replacement":null,"expansion":null}],"children":[],"rendered":null}
$ echo$?
101

[Mark-Simulacrum]

Right, I think the fix I suggested here: #42230 (comment) should help.

[Mark-Simulacrum]

@bors r+ rollup

[bors]

📌 Commit 2160b4a has been approved by Mark-Simulacrum