Cannot run benchmarks with `panic = "abort"`

[AaronFriel]

The following error is obtained when running cargo bench, with the a panic = "abort" option in cargo.toml:

error: the linked panic runtime `panic_unwind` is not compiled with this crate's panic strategy `abort`

The cargo.toml needs to set the panic behavior in [profile.bench], e.g.:

cargo.toml:

[package]
name = "foobar"
version = "0.1.0"
authors = ["Aaron Friel <mayreply@aaronfriel.com>"]

[dependencies]
clap="^2.13.0"

[profile.bench]
panic = "abort"

[alexcrichton]

Dug a bit more into this today. The dependency actually isn't needed here to trigger the bug, and if you configure profile.test with abort then cargo test is also broken.

The problem here is that libtest, Rust's testing framework, requires the unwind panic mode and is incompatible with panic = "abort". If you configure profile.dev to have panic = "abort", it actually compiles all dependencies with -Cpanic=unwind when you execute cargo test to satisfy this constraint.

The "fix" here would be to ignore panic = "abort" in the bench and test profiles.

[AaronFriel]

The patch in #3175 is confusing to me. Is there any way to run tests or benchmarks with panic="abort"?

[alexcrichton]

Unfortunately no because they all link to libtest which is compiled with panic=unwind :(

[AaronFriel]

I see, and because libtest depends on panics to observe assert! failures, that's the blocking issue?

Is there any work on making an alternative libtest based on Result<>, with an, e.g.: try_assert! that works like try!?

[alexcrichton]

Perhaps yeah, but that's more of a rust-lang/rust issue than a Cargo one.

[AaronFriel]

Interesting. If I were to make an alternative libtest, is there a way to specify that in cargo.toml? Or are tests (and their return types) part of rust-lang/rust?

[alexcrichton]

Yeah you can specify harness = false in which case Cargo will just compile the test as an executable, and then you can link to whatever