[INFO] fetching crate fallible_collections 0.3.1...
[INFO] checking fallible_collections-0.3.1 against master#6526e5c772f2da07db745c94ca6bb0a591a39ba4 for pr-80920
[INFO] extracting crate fallible_collections 0.3.1 into /workspace/builds/worker-7/source
[INFO] validating manifest of crates.io crate fallible_collections 0.3.1 on toolchain 6526e5c772f2da07db745c94ca6bb0a591a39ba4
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+6526e5c772f2da07db745c94ca6bb0a591a39ba4" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking crates.io crate fallible_collections 0.3.1
[INFO] finished tweaking crates.io crate fallible_collections 0.3.1
[INFO] tweaked toml for crates.io crate fallible_collections 0.3.1 written to /workspace/builds/worker-7/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+6526e5c772f2da07db745c94ca6bb0a591a39ba4" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+6526e5c772f2da07db745c94ca6bb0a591a39ba4" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/source:/opt/rustwide/workdir:ro,Z" "-v" "/var/lib/crater-agent-workspace/cargo-home:/opt/rustwide/cargo-home:ro,Z" "-v" "/var/lib/crater-agent-workspace/rustup-home:/opt/rustwide/rustup-home:ro,Z" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--user" "0:0" "--network" "none" "rustops/crates-build-env@sha256:21f1ed92105a0ef9b0d27ad8bdeb7f36f9f01ac17fffe3a3f3dc5241fc25d8f4" "/opt/rustwide/cargo-home/bin/cargo" "+6526e5c772f2da07db745c94ca6bb0a591a39ba4" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] ec9e8606cc8c03d5614089778f8d22f86b4a7197d38c56057ec825b713e2d527
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] running `Command { std: "docker" "start" "-a" "ec9e8606cc8c03d5614089778f8d22f86b4a7197d38c56057ec825b713e2d527", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "ec9e8606cc8c03d5614089778f8d22f86b4a7197d38c56057ec825b713e2d527", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "ec9e8606cc8c03d5614089778f8d22f86b4a7197d38c56057ec825b713e2d527", kill_on_drop: false }`
[INFO] [stdout] ec9e8606cc8c03d5614089778f8d22f86b4a7197d38c56057ec825b713e2d527
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/source:/opt/rustwide/workdir:ro,Z" "-v" "/var/lib/crater-agent-workspace/cargo-home:/opt/rustwide/cargo-home:ro,Z" "-v" "/var/lib/crater-agent-workspace/rustup-home:/opt/rustwide/rustup-home:ro,Z" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=forbid" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--user" "0:0" "--network" "none" "rustops/crates-build-env@sha256:21f1ed92105a0ef9b0d27ad8bdeb7f36f9f01ac17fffe3a3f3dc5241fc25d8f4" "/opt/rustwide/cargo-home/bin/cargo" "+6526e5c772f2da07db745c94ca6bb0a591a39ba4" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] afb8f0d62ba78cfc3a934964f75408e47f5b69e2a4a96b1be449a8a99552bfa5
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] running `Command { std: "docker" "start" "-a" "afb8f0d62ba78cfc3a934964f75408e47f5b69e2a4a96b1be449a8a99552bfa5", kill_on_drop: false }`
[INFO] [stderr]     Checking fallible_collections v0.3.1 (/opt/rustwide/workdir)
[INFO] [stdout] warning: a method with this name may be added to the standard library in the future
[INFO] [stdout]   --> src/boxed.rs:28:20
[INFO] [stdout]    |
[INFO] [stdout] 28 |             inner: Box::try_new(t)?,
[INFO] [stdout]    |                    ^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unstable_name_collisions)]` on by default
[INFO] [stdout]    = warning: once this method is added to the standard library, the ambiguity may cause an error or change in behavior!
[INFO] [stdout]    = note: for more information, see issue #48919 <https://github.com/rust-lang/rust/issues/48919>
[INFO] [stdout]    = help: call with fully qualified syntax `boxed::FallibleBox::try_new(...)` to keep using the current method
[INFO] [stdout]    = help: add `#![feature(allocator_api)]` to the crate attributes to enable `Box::<T>::try_new`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: a method with this name may be added to the standard library in the future
[INFO] [stdout]   --> src/boxed.rs:95:9
[INFO] [stdout]    |
[INFO] [stdout] 95 |         Self::try_new(Borrow::<T>::borrow(self).try_clone()?)
[INFO] [stdout]    |         ^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = warning: once this method is added to the standard library, the ambiguity may cause an error or change in behavior!
[INFO] [stdout]    = note: for more information, see issue #48919 <https://github.com/rust-lang/rust/issues/48919>
[INFO] [stdout]    = help: call with fully qualified syntax `boxed::FallibleBox::try_new(...)` to keep using the current method
[INFO] [stdout]    = help: add `#![feature(allocator_api)]` to the crate attributes to enable `Box::<T>::try_new`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: a method with this name may be added to the standard library in the future
[INFO] [stdout]   --> src/boxed.rs:28:20
[INFO] [stdout]    |
[INFO] [stdout] 28 |             inner: Box::try_new(t)?,
[INFO] [stdout]    |                    ^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unstable_name_collisions)]` on by default
[INFO] [stdout]    = warning: once this method is added to the standard library, the ambiguity may cause an error or change in behavior!
[INFO] [stdout]    = note: for more information, see issue #48919 <https://github.com/rust-lang/rust/issues/48919>
[INFO] [stdout]    = help: call with fully qualified syntax `boxed::FallibleBox::try_new(...)` to keep using the current method
[INFO] [stdout]    = help: add `#![feature(allocator_api)]` to the crate attributes to enable `std::boxed::Box::<T>::try_new`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: a method with this name may be added to the standard library in the future
[INFO] [stdout]   --> src/boxed.rs:95:9
[INFO] [stdout]    |
[INFO] [stdout] 95 |         Self::try_new(Borrow::<T>::borrow(self).try_clone()?)
[INFO] [stdout]    |         ^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = warning: once this method is added to the standard library, the ambiguity may cause an error or change in behavior!
[INFO] [stdout]    = note: for more information, see issue #48919 <https://github.com/rust-lang/rust/issues/48919>
[INFO] [stdout]    = help: call with fully qualified syntax `boxed::FallibleBox::try_new(...)` to keep using the current method
[INFO] [stdout]    = help: add `#![feature(allocator_api)]` to the crate attributes to enable `std::boxed::Box::<T>::try_new`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: a method with this name may be added to the standard library in the future
[INFO] [stdout]    --> src/boxed.rs:104:21
[INFO] [stdout]     |
[INFO] [stdout] 104 |         let mut v = Box::try_new(5).unwrap();
[INFO] [stdout]     |                     ^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: once this method is added to the standard library, the ambiguity may cause an error or change in behavior!
[INFO] [stdout]     = note: for more information, see issue #48919 <https://github.com/rust-lang/rust/issues/48919>
[INFO] [stdout]     = help: call with fully qualified syntax `boxed::FallibleBox::try_new(...)` to keep using the current method
[INFO] [stdout]     = help: add `#![feature(allocator_api)]` to the crate attributes to enable `std::boxed::Box::<T>::try_new`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: a method with this name may be added to the standard library in the future
[INFO] [stdout]    --> src/boxed.rs:118:17
[INFO] [stdout]     |
[INFO] [stdout] 118 |         let b = Box::try_new(()).expect("ok");
[INFO] [stdout]     |                 ^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: once this method is added to the standard library, the ambiguity may cause an error or change in behavior!
[INFO] [stdout]     = note: for more information, see issue #48919 <https://github.com/rust-lang/rust/issues/48919>
[INFO] [stdout]     = help: call with fully qualified syntax `boxed::FallibleBox::try_new(...)` to keep using the current method
[INFO] [stdout]     = help: add `#![feature(allocator_api)]` to the crate attributes to enable `std::boxed::Box::<T>::try_new`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: a method with this name may be added to the standard library in the future
[INFO] [stdout]   --> src/rc.rs:17:17
[INFO] [stdout]    |
[INFO] [stdout] 17 |         let b = Box::try_new(t)?;
[INFO] [stdout]    |                 ^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = warning: once this method is added to the standard library, the ambiguity may cause an error or change in behavior!
[INFO] [stdout]    = note: for more information, see issue #48919 <https://github.com/rust-lang/rust/issues/48919>
[INFO] [stdout]    = help: call with fully qualified syntax `boxed::FallibleBox::try_new(...)` to keep using the current method
[INFO] [stdout]    = help: add `#![feature(allocator_api)]` to the crate attributes to enable `Box::<T>::try_new`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: a method with this name may be added to the standard library in the future
[INFO] [stdout]   --> src/arc.rs:21:17
[INFO] [stdout]    |
[INFO] [stdout] 21 |         let b = Box::try_new(t)?;
[INFO] [stdout]    |                 ^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = warning: once this method is added to the standard library, the ambiguity may cause an error or change in behavior!
[INFO] [stdout]    = note: for more information, see issue #48919 <https://github.com/rust-lang/rust/issues/48919>
[INFO] [stdout]    = help: call with fully qualified syntax `boxed::FallibleBox::try_new(...)` to keep using the current method
[INFO] [stdout]    = help: add `#![feature(allocator_api)]` to the crate attributes to enable `Box::<T>::try_new`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: a method with this name may be added to the standard library in the future
[INFO] [stdout]   --> src/rc.rs:17:17
[INFO] [stdout]    |
[INFO] [stdout] 17 |         let b = Box::try_new(t)?;
[INFO] [stdout]    |                 ^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = warning: once this method is added to the standard library, the ambiguity may cause an error or change in behavior!
[INFO] [stdout]    = note: for more information, see issue #48919 <https://github.com/rust-lang/rust/issues/48919>
[INFO] [stdout]    = help: call with fully qualified syntax `boxed::FallibleBox::try_new(...)` to keep using the current method
[INFO] [stdout]    = help: add `#![feature(allocator_api)]` to the crate attributes to enable `std::boxed::Box::<T>::try_new`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: a method with this name may be added to the standard library in the future
[INFO] [stdout]   --> src/arc.rs:21:17
[INFO] [stdout]    |
[INFO] [stdout] 21 |         let b = Box::try_new(t)?;
[INFO] [stdout]    |                 ^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = warning: once this method is added to the standard library, the ambiguity may cause an error or change in behavior!
[INFO] [stdout]    = note: for more information, see issue #48919 <https://github.com/rust-lang/rust/issues/48919>
[INFO] [stdout]    = help: call with fully qualified syntax `boxed::FallibleBox::try_new(...)` to keep using the current method
[INFO] [stdout]    = help: add `#![feature(allocator_api)]` to the crate attributes to enable `std::boxed::Box::<T>::try_new`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 4 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 6 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 1.24s
[INFO] running `Command { std: "docker" "inspect" "afb8f0d62ba78cfc3a934964f75408e47f5b69e2a4a96b1be449a8a99552bfa5", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "afb8f0d62ba78cfc3a934964f75408e47f5b69e2a4a96b1be449a8a99552bfa5", kill_on_drop: false }`
[INFO] [stdout] afb8f0d62ba78cfc3a934964f75408e47f5b69e2a4a96b1be449a8a99552bfa5