[INFO] fetching crate slog-config 0.4.0...
[INFO] checking slog-config-0.4.0 against master#03c609abb6638f9d7f49f34326d4137d07f5cd61 for pr-155945
[INFO] extracting crate slog-config 0.4.0 into /workspace/builds/worker-6-tc1/source
[INFO] started tweaking crates.io crate slog-config 0.4.0
[INFO] finished tweaking crates.io crate slog-config 0.4.0
[INFO] tweaked toml for crates.io crate slog-config 0.4.0 written to /workspace/builds/worker-6-tc1/source/Cargo.toml
[INFO] validating manifest of crates.io crate slog-config 0.4.0 on toolchain 03c609abb6638f9d7f49f34326d4137d07f5cd61
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+03c609abb6638f9d7f49f34326d4137d07f5cd61" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+03c609abb6638f9d7f49f34326d4137d07f5cd61" "generate-lockfile" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Updating crates.io index
[INFO] [stderr] error: failed to select a version for `toml`.
[INFO] [stderr]     ... required by package `slog-config v0.4.0 (/workspace/builds/worker-6-tc1/source)`
[INFO] [stderr] versions that meet the requirements `^0.4` are: 0.4.10, 0.4.9, 0.4.8, 0.4.7, 0.4.6, 0.4.5, 0.4.4, 0.4.3, 0.4.2, 0.4.1, 0.4.0
[INFO] [stderr] 
[INFO] [stderr] package `slog-config` depends on `toml` with feature `serde` but `toml` does not have that feature.
[INFO] [stderr] note: a required dependency with that name exists, but only optional dependencies can be used as features.
[INFO] [stderr] 
[INFO] [stderr] 
[INFO] [stderr] failed to select a version for `toml` which could resolve this conflict


overridden task result to prepare-fail:unknown

Caused by:
    0: uncategorized prepare error
    1: command failed: exit status: 101
       
           Updating crates.io index
       error: failed to select a version for `toml`.
           ... required by package `slog-config v0.4.0 (/workspace/builds/worker-6-tc1/source)`
       versions that meet the requirements `^0.4` are: 0.4.10, 0.4.9, 0.4.8, 0.4.7, 0.4.6, 0.4.5, 0.4.4, 0.4.3, 0.4.2, 0.4.1, 0.4.0
       
       package `slog-config` depends on `toml` with feature `serde` but `toml` does not have that feature.
       note: a required dependency with that name exists, but only optional dependencies can be used as features.
       
       
       failed to select a version for `toml` which could resolve this conflict