Fix build errors due to rust-lang/rust#60444

Author: ipetkov

.travis.yml

@@ -19,6 +19,18 @@ matrix:
       sudo: required # Work around for travis-ci/travis-ci#9061
       env:
         - RUSTFLAGS="-C link-dead-code" # Enable better code coverage at the cost of binary size
+      script:
+        - cargo check --no-default-features
+          # NB: don't run with the top-level feature enabled see rust-lang/rust#60444
+        - cargo check --no-default-features --features 'conch-parser'
+          # Retry with fewer cores if the initial `cargo test` fails to work around possible OOM errors
+          # for more details see https://github.com/rust-lang/cargo/issues/4415
+        - cargo test --no-fail-fast --no-default-features --features 'conch-parser' ||
+          (
+            echo 'initial `cargo test` failed, retrying with fewer cores to work around OOM issues' &&
+            cargo test --no-fail-fast --verbose -j 1
+            cargo test --no-fail-fast --no-default-features --features 'conch-parser' ||
+          )
       after_success:
         - ./ci/install-kcov.sh && ./ci/coverage.sh
 

src/lib.rs

@@ -31,6 +31,8 @@
 
 #![doc(html_root_url = "https://docs.rs/conch-runtime/0.1")]
 
+#![cfg_attr(all(feature = "conch-parser", feature = "top-level"), recursion_limit="128")]
+
 #![cfg_attr(feature = "clippy", feature(plugin))]
 #![cfg_attr(feature = "clippy", plugin(clippy))]