Running `rustc --crate-name lettre_email /tmp/.cargo/registry/src/github.com-1ecc6299db9ec823/lettre_email-0.8.3/src/lib.rs --color never --crate-type lib --emit=dep-info,metadata,link -C opt-level=s -C metadata=5a27dd1f6543c759 -C extra-filename=-5a27dd1f6543c759 --out-dir /tmp/4c4d3b61/target/release/deps -L dependency=/tmp/4c4d3b61/target/release/deps --extern base64=/tmp/4c4d3b61/target/release/deps/libbase64-f7445eceaf547ba9.rlib --extern email=/tmp/4c4d3b61/target/release/deps/libemail-e4e2ed35eddf5bec.rlib --extern lettre=/tmp/4c4d3b61/target/release/deps/liblettre-570c40bb33fa8863.rlib --extern mime=/tmp/4c4d3b61/target/release/deps/libmime-67478e7a6103037f.rlib --extern time=/tmp/4c4d3b61/target/release/deps/libtime-dd42bbf9b0e00a33.rlib --extern uuid=/tmp/4c4d3b61/target/release/deps/libuuid-d95cfca80b722681.rlib --cap-lints allow -C target-cpu=ivybridge -C target-feature=-aes,-avx,+fxsr,-popcnt,+sse,+sse2,-sse3,-sse4.1,-sse4.2,-ssse3,-xsave,-xsaveopt`



error[E0283]: type annotations required: cannot resolve `std::string::String: std::convert::AsRef<_>`
   --> /tmp/.cargo/registry/src/github.com-1ecc6299db9ec823/lettre_email-0.8.3/src/lib.rs:387:70
    |
387 |         self.add_header(("Content-Type", format!("{}", content_type).as_ref()));
    |                                                                      ^^^^^^



error: aborting due to previous error

For more information about this error, try `rustc --explain E0283`.



error: Could not compile `lettre_email`.

Caused by:
  process didn't exit successfully: `rustc --crate-name lettre_email /tmp/.cargo/registry/src/github.com-1ecc6299db9ec823/lettre_email-0.8.3/src/lib.rs --color never --crate-type lib --emit=dep-info,metadata,link -C opt-level=s -C metadata=5a27dd1f6543c759 -C extra-filename=-5a27dd1f6543c759 --out-dir /tmp/4c4d3b61/target/release/deps -L dependency=/tmp/4c4d3b61/target/release/deps --extern base64=/tmp/4c4d3b61/target/release/deps/libbase64-f7445eceaf547ba9.rlib --extern email=/tmp/4c4d3b61/target/release/deps/libemail-e4e2ed35eddf5bec.rlib --extern lettre=/tmp/4c4d3b61/target/release/deps/liblettre-570c40bb33fa8863.rlib --extern mime=/tmp/4c4d3b61/target/release/deps/libmime-67478e7a6103037f.rlib --extern time=/tmp/4c4d3b61/target/release/deps/libtime-dd42bbf9b0e00a33.rlib --extern uuid=/tmp/4c4d3b61/target/release/deps/libuuid-d95cfca80b722681.rlib --cap-lints allow -C target-cpu=ivybridge -C target-feature=-aes,-avx,+fxsr,-popcnt,+sse,+sse2,-sse3,-sse4.1,-sse4.2,-ssse3,-xsave,-xsaveopt` (exit code: 1)
warning: build failed, waiting for other jobs to finish...



error: build failed



failed to `cargo build`



{ Error: Command failed: cargo build --verbose --release
    at makeError (/tmp/22454875/.build-utils/.builder/node_modules/execa/index.js:174:9)
    at Promise.all.then.arr (/tmp/22454875/.build-utils/.builder/node_modules/execa/index.js:278:16)
    at <anonymous>
    at process._tickDomainCallback (internal/process/next_tick.js:228:7)
  code: 101,
  stdout: null,
  stderr: null,
  failed: true,
  signal: null,
  cmd: 'cargo build --verbose --release',
  timedOut: false,
  killed: false }