2 files changed, 4 insertions, 7 deletions
diff --git a/compiler/rustc_incremental/src/persist/dirty_clean.rs b/compiler/rustc_incremental/src/persist/dirty_clean.rs
index a8acaf659..ed7b272b1 100644
--- a/compiler/rustc_incremental/src/persist/dirty_clean.rs
+++ b/compiler/rustc_incremental/src/persist/dirty_clean.rs
@@ -1,4 +1,4 @@
-//! Debugging code to test fingerprints computed for query results.  For each node marked with
+//! Debugging code to test fingerprints computed for query results. For each node marked with
 //! `#[rustc_clean]` we will compare the fingerprint from the current and from the previous
 //! compilation session as appropriate:
 //!
@@ -30,8 +30,6 @@ use rustc_middle::hir::nested_filter;
 use rustc_middle::ty::TyCtxt;
 use rustc_span::symbol::{sym, Symbol};
 use rustc_span::Span;
-use std::iter::FromIterator;
-use std::vec::Vec;
 
 const LOADED_FROM_DISK: Symbol = sym::loaded_from_disk;
 const EXCEPT: Symbol = sym::except;
diff --git a/compiler/rustc_incremental/src/persist/fs.rs b/compiler/rustc_incremental/src/persist/fs.rs
index 97ebed058..1fd2b9b0d 100644
--- a/compiler/rustc_incremental/src/persist/fs.rs
+++ b/compiler/rustc_incremental/src/persist/fs.rs
@@ -113,7 +113,6 @@ use rustc_span::Symbol;
 
 use std::fs as std_fs;
 use std::io::{self, ErrorKind};
-use std::mem;
 use std::path::{Path, PathBuf};
 use std::time::{Duration, SystemTime, UNIX_EPOCH};
 
@@ -305,7 +304,7 @@ pub fn prepare_session_directory(
             }
 
             delete_session_dir_lock_file(sess, &lock_file_path);
-            mem::drop(directory_lock);
+            drop(directory_lock);
         }
     }
 }
@@ -864,7 +863,7 @@ pub fn garbage_collect_session_directories(sess: &Session) -> io::Result<()> {
 
                     // Let's make it explicit that the file lock is released at this point,
                     // or rather, that we held on to it until here
-                    mem::drop(lock);
+                    drop(lock);
                 }
                 Err(_) => {
                     debug!(
@@ -898,7 +897,7 @@ pub fn garbage_collect_session_directories(sess: &Session) -> io::Result<()> {
 
         // Let's make it explicit that the file lock is released at this point,
         // or rather, that we held on to it until here
-        mem::drop(lock);
+        drop(lock);
     }
 
     Ok(())