Dogfood feature(file_buffered)

compiler/rustc_interface/src/lib.rs

@@ -1,5 +1,6 @@
 // tidy-alphabetical-start
 #![feature(decl_macro)]
+#![feature(file_buffered)]
 #![feature(let_chains)]
 #![feature(try_blocks)]
 #![warn(unreachable_pub)]

compiler/rustc_interface/src/passes.rs

@@ -519,7 +519,7 @@ fn write_out_deps(tcx: TyCtxt<'_>, outputs: &OutputFilenames, out_filenames: &[P
                 write_deps_to_file(&mut file)?;
             }
             OutFileName::Real(ref path) => {
-                let mut file = BufWriter::new(fs::File::create(path)?);
+                let mut file = fs::File::create_buffered(path)?;
                 write_deps_to_file(&mut file)?;
             }
         }