make compiletest aware whether compiler was built with debug assertions

[matthiaskrgr]

I would like to be able to add tests of the form:
"rustc must crash on this file, but only if the compiler was built with debug assertions, otherwise the test shall be ignored (since it wont crash)"

[jieyouxu]

@matthiaskrgr does //@ only-debug do what you want? cf. https://rustc-dev-guide.rust-lang.org/tests/directives.html?highlight=ignore-debug#controlling-when-tests-are-run.

[matthiaskrgr]

error: detected unknown compiletest test directive `only-debug` in /home/matthias/vcs/github/rust/tests/crashes/1234.rs:2
errors encountered during EarlyProps parsing: /home/matthias/vcs/github/rust/tests/crashes/1234.rs
thread 'main' panicked at src/tools/compiletest/src/header.rs:68:13:
errors encountered during EarlyProps parsing

¯\_(ツ)_/¯

[jieyouxu]

Okay I see, historically there was a // only-debug, but it was never actually used in the test suite, it it's absent from the command-list allowlist. It also doesn't do what you want because that's conditional on std debug assertions.