--- a/native/engine/src/flink_functions/certified/printf.rs
+++ b/native/engine/src/flink_functions/certified/printf.rs
@@ -176,15 +176,6 @@
                         value.to_string()
                     }
                 }
-                // Formatter treats any non-NULL boxed integer, including zero, as true.
-                b'b' | b'B'
-                    if matches!(
-                        arg.data_type(),
-                        DataType::Int8 | DataType::Int16 | DataType::Int32 | DataType::Int64
-                    ) =>
-                {
-                    "true".to_owned()
-                }
                 b'f' => {
                     // The released SQL evaluator passes DecimalData, not BigDecimal.
                     // Formatter rejects it for %f; retain that evaluator for numeric formats.
@@ -226,7 +217,7 @@
                     }
                     result
                 }
-                _ => return None,
+                _ => integer_boolean(conversion, arg)?.to_owned(),
             }
         };
         if precision.is_some() && !matches!(conversion, b's' | b'S' | b'b' | b'B' | b'f') {
@@ -254,6 +245,18 @@
         }
     }
     Some(())
+}
+
+// Keep this extension out of the existing numeric dispatch's inlined branches.
+#[inline(never)]
+fn integer_boolean(conversion: u8, arg: &ArrayRef) -> Option<&'static str> {
+    // Formatter treats any non-NULL boxed integer, including zero, as true.
+    (matches!(conversion, b'b' | b'B')
+        && matches!(
+            arg.data_type(),
+            DataType::Int8 | DataType::Int16 | DataType::Int32 | DataType::Int64
+        ))
+    .then_some("true")
 }
 
 fn fixed_decimal(value: i128, scale: i8) -> Option<String> {