thread 'main' panicked at 'called Option::unwrap() on a None value', /checkout/src/libcore/option.rs:323

[crazyjin]

#git clone https://github.com/SergioBenitez/rocket
#cd rocket/examples/hello_world
#cargo run
thread 'main' panicked at 'called Option::unwrap() on a None value', /checkout/src/libcore/option.rs:323
note: Some details are omitted, run with RUST_BACKTRACE=full for a verbose backtrace.
stack backtrace:
0: cargo::version
at /checkout/src/libcore/macros.rs:21
at /checkout/cargo/src/cargo/lib.rs:263
1: cargo::ops::registry::http_handle
at /checkout/cargo/src/cargo/ops/registry.rs:227
2: <cargo::sources::registry::remote::RemoteRegistry<'cfg> as cargo::sources::registry::RegistryData>::update_index
at /checkout/cargo/src/cargo/sources/registry/remote.rs:63
3: cargo::sources::registry::RegistrySource::do_update
at /checkout/cargo/src/cargo/sources/registry/mod.rs:309
4: <cargo::sources::registry::RegistrySource<'cfg> as cargo::core::source::Source>::update
at /checkout/cargo/src/cargo/sources/registry/mod.rs:353
5: cargo::core::registry::PackageRegistry::ensure_loaded
at /checkout/cargo/src/cargo/core/registry.rs:191
at /checkout/cargo/src/cargo/util/errors.rs:58
at /checkout/cargo/src/cargo/core/registry.rs:180
at /checkout/cargo/src/cargo/core/registry.rs:141
6: <cargo::core::registry::PackageRegistry<'cfg> as cargo::core::registry::Registry>::query
at /checkout/cargo/src/cargo/core/registry.rs:339
7: <&'a mut I as core::iter::iterator::Iterator>::next
at /checkout/cargo/src/cargo/core/resolver/mod.rs:859
at /checkout/cargo/src/cargo/core/resolver/mod.rs:832
at /checkout/src/libcore/ops.rs:2654
at /checkout/src/libcore/option.rs:383
at /checkout/src/libcore/iter/mod.rs:999
at /checkout/src/libcore/result.rs:1087
at /checkout/src/libcore/iter/iterator.rs:2197
8: cargo::core::resolver::activate
at /checkout/src/libcollections/vec.rs:1653
at /checkout/src/libcollections/vec.rs:1566
at /checkout/src/libcore/result.rs:1104
at /checkout/src/libcore/iter/iterator.rs:1221
at /checkout/cargo/src/cargo/core/resolver/mod.rs:831
at /checkout/cargo/src/cargo/core/resolver/mod.rs:340
9: cargo::core::resolver::activate_deps_loop
at /checkout/cargo/src/cargo/core/resolver/mod.rs:457
10: cargo::core::resolver::resolve
at /checkout/cargo/src/cargo/core/resolver/mod.rs:280
11: cargo::ops::resolve::resolve_with_previous
at /checkout/cargo/src/cargo/ops/resolve.rs:225
12: cargo::ops::resolve::resolve_with_registry
at /checkout/cargo/src/cargo/ops/resolve.rs:88
13: cargo::ops::resolve::resolve_ws_precisely
at /checkout/cargo/src/cargo/ops/resolve.rs:43
14: cargo::ops::cargo_compile::compile_ws
at /checkout/cargo/src/cargo/ops/cargo_compile.rs:177
15: cargo::ops::cargo_compile::compile_with_exec
at /checkout/cargo/src/cargo/ops/cargo_compile.rs:153
16: cargo::ops::cargo_run::run
at /checkout/cargo/src/cargo/ops/cargo_compile.rs:141
at /checkout/cargo/src/cargo/ops/cargo_run.rs:55
17: cargo::try_execute_builtin_command
at /checkout/cargo/src/bin/run.rs:108
at /checkout/cargo/src/cargo/lib.rs:128
at /checkout/cargo/src/bin/cargo.rs:259
18: cargo::execute
at /checkout/cargo/src/bin/cargo.rs:223
19: cargo::call_main_without_stdin
at /checkout/cargo/src/cargo/lib.rs:128
20: cargo::main
at /checkout/cargo/src/bin/cargo.rs:91
at /checkout/cargo/src/bin/cargo.rs:84

#rustc --version
rustc 1.17.0-nightly (a559452b0 2017-03-17)

[Eijebong]

That was a regression in rust/cargo. There is a second one though that impacts rocket, see #235

[SergioBenitez]

Rust nightly 2017-03-17 shipped with a bug in cargo (rust-lang/cargo#3844), resulting in what you see there. Rust nightly 2017-03-18 shipped with a bug in rustc (rust-lang/rust#40663, fixed in rust-lang/rust#40664, discussed in #235) that affected Rocket. The last fully working nightly release is 2017-03-16. Use rustup default nightly-2017-03-16 to switch to this version. Once the rustc bug has been fixed, a new version of Rocket will be released. At this point, you'll need to switch to the latest nightly via rustup default nightly.

Closing this as a "duplicate" of #235.

[crazyjin]

@SergioBenitez @Eijebong Thank you for all your work on rocket. I swithed to the last nightly-2017-03-16 and problem solved.