Upgrade the fortanix-sgx-abi dependency

[tgross35]

0.6.1 removes the compiler-builtins dependency, part of RUST-142265. The breaking change from 0.5 to 0.6 is for an update to the insecure_time API [1].

I validated that ./x c library --target x86_64-fortanix-unknown-sgx completes successfully with this change.

Link: fortanix/rust-sgx@a34e976 [1]

[rustbot]

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[rustbot]

These commits modify the library/Cargo.lock file. Unintentional changes to library/Cargo.lock can be introduced when switching branches and rebasing PRs.

If this was unintentional then you should revert the changes before this PR is merged.
Otherwise, you can ignore this comment.

[tgross35]

@jethrogb mind taking a look at this?

[jethrogb]

Unfortunately, we're missing documentation for the modified insecure_time call so I don't know if this is correct.

[tgross35]

Is this unimplemented!() the actual function, or does it get hooked somewhere? I'm having some difficulty tracing this back https://github.com/fortanix/rust-sgx/blob/adcc6cdb981bcf2101437edbd3ef6144246621d3/intel-sgx/fortanix-sgx-abi/src/lib.rs#L584. I'm thinking that if it is actually an unconditional panic, the function body for insecure_time here could become unimplemented!() rather than calling raw::insecure_time so we can upgrade without concern of the API change.

[jethrogb]

fortanix-sgx-abi just contains definitions describing the ABI. The implementations exist elsewhere:

https://github.com/rust-lang/rust/blob/master/library/std/src/sys/pal/sgx/abi/usercalls/raw.rs
https://github.com/fortanix/rust-sgx/blob/master/intel-sgx/enclave-runner/src/usercalls/abi.rs

But without documentation it's not really possible to determine whether the implementation is correct.