disabling tests incompatible with miri

[devnexen]

No description provided.

[asomers]

Frankly, I'm surprised that anything in this crate works with Miri. How are you invoking it, any way?

[asomers]

Two problems with the changelog message:

• Integration tests are affected as well as unit tests.
• You disabled the tests conditionally, not unconditionally.

Suggested change

	Disabled unit tests incompatible with Miri.
	Fix running tests with Miri.

You should make a similar change to the commit message, too.

[SteveLauC]

How are you invoking it, any way?

I am also interested in how you test Nix with miri, I tried cargo +nightly miri test --all-features against your branch on my host, but I still got errors:

$ cargo +nightly miri test --all-features
...
test test_fcntl::test_posix_fadvise::test_success ... error: unsupported operation: `open` not available when isolation is enabled
    --> /home/steve/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/std/src/sys/pal/unix/fs.rs:1133:36
     |
1133 |         let fd = cvt_r(|| unsafe { open64(path.as_ptr(), flags, opts.mode as c_int) })?;
     |                                    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ `open` not available when isolation is enabled
...

And, what is the advantage of doing so if we don't add Miri to our CI?

[devnexen]

How are you invoking it, any way?

I am also interested in how you test Nix with miri, I tried cargo +nightly miri test --all-features against your branch on my host, but I still got errors:

$ cargo +nightly miri test --all-features
...
test test_fcntl::test_posix_fadvise::test_success ... error: unsupported operation: `open` not available when isolation is enabled
    --> /home/steve/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/std/src/sys/pal/unix/fs.rs:1133:36
     |
1133 |         let fd = cvt_r(|| unsafe { open64(path.as_ptr(), flags, opts.mode as c_int) })?;
     |                                    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ `open` not available when isolation is enabled
...

And, what is the advantage of doing so if we don't add Miri to our CI?

Try with the following MIRIFLAGS="-Zmiri-disable-isolation -Zmiri-permissive-provenance"

[asomers]

I'm inclined not to merge this PR. Not because it's wrong, but because I don't think that miri is of much use to a crate like this one, and the changes included in this PR add a lot of line noise. What do you think, @devnexen ?

[devnexen]

yes true that s adding a lot of lines and we ll most likely need to care for this with new tests.