diff --git a/logos-codegen/src/graph/regex.rs b/logos-codegen/src/graph/regex.rs
index 40aa1c02..d351a5f5 100644
--- a/logos-codegen/src/graph/regex.rs
+++ b/logos-codegen/src/graph/regex.rs
@@ -178,7 +178,7 @@ fn is_one_ascii(class: &ClassUnicode) -> bool {
     let start = range.start() as u32;
     let end = range.end() as u32;
 
-    start < 128 && end < 128
+    start < 128 && (end < 128 || end == 0x0010_FFFF)
 }
 
 #[cfg(test)]