diff --git a/src/librustc/session/mod.rs b/src/librustc/session/mod.rs
index a17825a877d8..fe94b62ef19e 100644
--- a/src/librustc/session/mod.rs
+++ b/src/librustc/session/mod.rs
@@ -868,7 +868,7 @@ impl Session {
                 let fuel = self.optimization_fuel_limit.get();
                 ret = fuel != 0;
                 if fuel == 0 && !self.out_of_fuel.get() {
-                    println!("optimization-fuel-exhausted: {}", msg());
+                    eprintln!("optimization-fuel-exhausted: {}", msg());
                     self.out_of_fuel.set(true);
                 } else if fuel > 0 {
                     self.optimization_fuel_limit.set(fuel - 1);
diff --git a/src/librustc_driver/lib.rs b/src/librustc_driver/lib.rs
index 276b7290c2ef..8a7d4a017431 100644
--- a/src/librustc_driver/lib.rs
+++ b/src/librustc_driver/lib.rs
@@ -944,7 +944,7 @@ impl<'a> CompilerCalls<'a> for RustcDefaultCalls {
             control.compilation_done.callback = box move |state| {
                 old_callback(state);
                 let sess = state.session;
-                println!("Fuel used by {}: {}",
+                eprintln!("Fuel used by {}: {}",
                     sess.print_fuel_crate.as_ref().unwrap(),
                     sess.print_fuel.get());
             }