diff --git a/library/core/src/unicode/unicode_data.rs b/library/core/src/unicode/unicode_data.rs
index eb9334bdc6d..c1eff3a36e6 100644
--- a/library/core/src/unicode/unicode_data.rs
+++ b/library/core/src/unicode/unicode_data.rs
@@ -555,6 +555,7 @@ pub mod white_space {
         0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
         0, 0, 0, 0, 0, 0, 0, 0, 0,
     ];
+    #[inline]
     pub fn lookup(c: char) -> bool {
         match c as u32 >> 8 {
             0 => WHITESPACE_MAP[c as usize & 0xff] & 1 != 0,
diff --git a/src/tools/unicode-table-generator/src/cascading_map.rs b/src/tools/unicode-table-generator/src/cascading_map.rs
index d4efdef2e80..02c7542309a 100644
--- a/src/tools/unicode-table-generator/src/cascading_map.rs
+++ b/src/tools/unicode-table-generator/src/cascading_map.rs
@@ -63,6 +63,7 @@ pub fn emit_cascading_map(&mut self, ranges: &[Range<u32>]) -> bool {
             .unwrap();
         self.bytes_used += 256;
 
+        writeln!(&mut self.file, "#[inline]").unwrap();
         writeln!(&mut self.file, "pub fn lookup(c: char) -> bool {{").unwrap();
         writeln!(&mut self.file, "    match c as u32 >> 8 {{").unwrap();
         for arm in arms {