diff --git a/.cargo_vcs_info.json b/.cargo_vcs_info.json
index ed04b94..0a27b5e 100644
--- a/.cargo_vcs_info.json
+++ b/.cargo_vcs_info.json
@@ -1,5 +1,5 @@
 {
   "git": {
-    "sha1": "3589accc6d7b5bb99c6393ba8960849e87b64527"
+    "sha1": "d03ae186b5d9f4d92cb1312ca77e8d9b05efc84d"
   }
 }
diff --git a/Cargo.toml b/Cargo.toml
index 2e9d5f6..f4b1476 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -12,7 +12,7 @@
 
 [package]
 name = "regex-syntax"
-version = "0.6.20"
+version = "0.6.21"
 authors = ["The Rust Project Developers"]
 description = "A regular expression parser."
 homepage = "https://github.com/rust-lang/regex"
diff --git a/Cargo.toml.orig b/Cargo.toml.orig
index eb3ada9..7b56f32 100644
--- a/Cargo.toml.orig
+++ b/Cargo.toml.orig
@@ -1,6 +1,6 @@
 [package]
 name = "regex-syntax"
-version = "0.6.20"  #:version
+version = "0.6.21"  #:version
 authors = ["The Rust Project Developers"]
 license = "MIT/Apache-2.0"
 repository = "https://github.com/rust-lang/regex"
diff --git a/METADATA b/METADATA
index 70c34e5..dda6e41 100644
--- a/METADATA
+++ b/METADATA
@@ -7,13 +7,13 @@
   }
   url {
     type: ARCHIVE
-    value: "https://static.crates.io/crates/regex-syntax/regex-syntax-0.6.20.crate"
+    value: "https://static.crates.io/crates/regex-syntax/regex-syntax-0.6.21.crate"
   }
-  version: "0.6.20"
+  version: "0.6.21"
   license_type: NOTICE
   last_upgrade_date {
     year: 2020
-    month: 10
-    day: 26
+    month: 11
+    day: 2
   }
 }
diff --git a/src/hir/translate.rs b/src/hir/translate.rs
index 72f3f9a..44d2813 100644
--- a/src/hir/translate.rs
+++ b/src/hir/translate.rs
@@ -322,7 +322,7 @@
                         ast.negated,
                         &mut cls,
                     )?;
-                    if cls.iter().next().is_none() {
+                    if cls.ranges().is_empty() {
                         return Err(self.error(
                             ast.span,
                             ErrorKind::EmptyClassNotAllowed,
@@ -337,7 +337,7 @@
                         ast.negated,
                         &mut cls,
                     )?;
-                    if cls.iter().next().is_none() {
+                    if cls.ranges().is_empty() {
                         return Err(self.error(
                             ast.span,
                             ErrorKind::EmptyClassNotAllowed,
@@ -844,6 +844,11 @@
                 ast_class.negated,
                 class,
             )?;
+            if class.ranges().is_empty() {
+                let err = self
+                    .error(ast_class.span, ErrorKind::EmptyClassNotAllowed);
+                return Err(err);
+            }
         }
         result
     }
@@ -2318,6 +2323,21 @@
     }
 
     #[test]
+    #[cfg(feature = "unicode-gencat")]
+    fn class_unicode_any_empty() {
+        assert_eq!(
+            t_err(r"\P{any}"),
+            TestError {
+                kind: hir::ErrorKind::EmptyClassNotAllowed,
+                span: Span::new(
+                    Position::new(0, 1, 1),
+                    Position::new(7, 1, 8)
+                ),
+            }
+        );
+    }
+
+    #[test]
     #[cfg(not(feature = "unicode-age"))]
     fn class_unicode_age_disabled() {
         assert_eq!(