diff --git a/generator/bindtests.ml b/generator/bindtests.ml
index ff1ea4f06..a82beb600 100644
--- a/generator/bindtests.ml
+++ b/generator/bindtests.ml
@@ -992,7 +992,7 @@ and generate_rust_bindtests () =
   pr "fn main() {\n";
   pr "    let g = match Handle::create() {\n";
   pr "        Ok(g) => g,\n";
-  pr "        Err(e) => panic!(format!(\" could not create handle {:?}\", e)),\n";
+  pr "        Err(e) => panic!(\"could not create handle {:?}\", e),\n";
   pr "    };\n";
   generate_lang_bindtests (
     fun f args optargs ->
diff --git a/rust/src/bin/event.rs b/rust/src/bin/event.rs
index 3a3aa7d7c..07228b580 100644
--- a/rust/src/bin/event.rs
+++ b/rust/src/bin/event.rs
@@ -5,7 +5,7 @@ fn main() {
     for _ in 0..256 {
         let mut g = match Handle::create() {
             Ok(g) => g,
-            Err(e) => panic!(format!(" could not create handle {:?}", e)),
+            Err(e) => panic!("could not create handle {:?}", e),
         };
         g.set_event_callback(
             |e, _, _, _| match e {
diff --git a/rust/src/bin/event_leak.rs b/rust/src/bin/event_leak.rs
index 176de3c9a..78f6dc2c5 100644
--- a/rust/src/bin/event_leak.rs
+++ b/rust/src/bin/event_leak.rs
@@ -6,7 +6,7 @@ fn main() {
     for _ in 0..256 {
         let mut g = match Handle::create() {
             Ok(g) => g,
-            Err(e) => panic!(format!(" could not create handle {:?}", e)),
+            Err(e) => panic!("could not create handle {:?}", e),
         };
         g.set_event_callback(
             |e, _, _, _| match e {