3 files changed, 41 insertions, 20 deletions

diff --git a/src/libcore/char/methods.rs b/src/libcore/char/methods.rs
index c341bb552a1..2b52c48cb90 100644
--- a/src/libcore/char/methods.rs
+++ b/src/libcore/char/methods.rs
@@ -1072,8 +1072,9 @@ impl char {
     /// assert!(!esc.is_ascii_alphabetic());
     /// ```
     #[stable(feature = "ascii_ctype_on_intrinsics", since = "1.24.0")]
+    #[rustc_const_unstable(feature = "const_ascii_ctype_on_intrinsics", issue = "68983")]
     #[inline]
-    pub fn is_ascii_alphabetic(&self) -> bool {
+    pub const fn is_ascii_alphabetic(&self) -> bool {
         self.is_ascii() && (*self as u8).is_ascii_alphabetic()
     }
 
@@ -1104,8 +1105,9 @@ impl char {
     /// assert!(!esc.is_ascii_uppercase());
     /// ```
     #[stable(feature = "ascii_ctype_on_intrinsics", since = "1.24.0")]
+    #[rustc_const_unstable(feature = "const_ascii_ctype_on_intrinsics", issue = "68983")]
     #[inline]
-    pub fn is_ascii_uppercase(&self) -> bool {
+    pub const fn is_ascii_uppercase(&self) -> bool {
         self.is_ascii() && (*self as u8).is_ascii_uppercase()
     }
 
@@ -1136,8 +1138,9 @@ impl char {
     /// assert!(!esc.is_ascii_lowercase());
     /// ```
     #[stable(feature = "ascii_ctype_on_intrinsics", since = "1.24.0")]
+    #[rustc_const_unstable(feature = "const_ascii_ctype_on_intrinsics", issue = "68983")]
     #[inline]
-    pub fn is_ascii_lowercase(&self) -> bool {
+    pub const fn is_ascii_lowercase(&self) -> bool {
         self.is_ascii() && (*self as u8).is_ascii_lowercase()
     }
 
@@ -1171,8 +1174,9 @@ impl char {
     /// assert!(!esc.is_ascii_alphanumeric());
     /// ```
     #[stable(feature = "ascii_ctype_on_intrinsics", since = "1.24.0")]
+    #[rustc_const_unstable(feature = "const_ascii_ctype_on_intrinsics", issue = "68983")]
     #[inline]
-    pub fn is_ascii_alphanumeric(&self) -> bool {
+    pub const fn is_ascii_alphanumeric(&self) -> bool {
         self.is_ascii() && (*self as u8).is_ascii_alphanumeric()
     }
 
@@ -1203,8 +1207,9 @@ impl char {
     /// assert!(!esc.is_ascii_digit());
     /// ```
     #[stable(feature = "ascii_ctype_on_intrinsics", since = "1.24.0")]
+    #[rustc_const_unstable(feature = "const_ascii_ctype_on_intrinsics", issue = "68983")]
     #[inline]
-    pub fn is_ascii_digit(&self) -> bool {
+    pub const fn is_ascii_digit(&self) -> bool {
         self.is_ascii() && (*self as u8).is_ascii_digit()
     }
 
@@ -1238,8 +1243,9 @@ impl char {
     /// assert!(!esc.is_ascii_hexdigit());
     /// ```
     #[stable(feature = "ascii_ctype_on_intrinsics", since = "1.24.0")]
+    #[rustc_const_unstable(feature = "const_ascii_ctype_on_intrinsics", issue = "68983")]
     #[inline]
-    pub fn is_ascii_hexdigit(&self) -> bool {
+    pub const fn is_ascii_hexdigit(&self) -> bool {
         self.is_ascii() && (*self as u8).is_ascii_hexdigit()
     }
 
@@ -1274,8 +1280,9 @@ impl char {
     /// assert!(!esc.is_ascii_punctuation());
     /// ```
     #[stable(feature = "ascii_ctype_on_intrinsics", since = "1.24.0")]
+    #[rustc_const_unstable(feature = "const_ascii_ctype_on_intrinsics", issue = "68983")]
     #[inline]
-    pub fn is_ascii_punctuation(&self) -> bool {
+    pub const fn is_ascii_punctuation(&self) -> bool {
         self.is_ascii() && (*self as u8).is_ascii_punctuation()
     }
 
@@ -1306,8 +1313,9 @@ impl char {
     /// assert!(!esc.is_ascii_graphic());
     /// ```
     #[stable(feature = "ascii_ctype_on_intrinsics", since = "1.24.0")]
+    #[rustc_const_unstable(feature = "const_ascii_ctype_on_intrinsics", issue = "68983")]
     #[inline]
-    pub fn is_ascii_graphic(&self) -> bool {
+    pub const fn is_ascii_graphic(&self) -> bool {
         self.is_ascii() && (*self as u8).is_ascii_graphic()
     }
 
@@ -1355,8 +1363,9 @@ impl char {
     /// assert!(!esc.is_ascii_whitespace());
     /// ```
     #[stable(feature = "ascii_ctype_on_intrinsics", since = "1.24.0")]
+    #[rustc_const_unstable(feature = "const_ascii_ctype_on_intrinsics", issue = "68983")]
     #[inline]
-    pub fn is_ascii_whitespace(&self) -> bool {
+    pub const fn is_ascii_whitespace(&self) -> bool {
         self.is_ascii() && (*self as u8).is_ascii_whitespace()
     }
 
@@ -1389,8 +1398,9 @@ impl char {
     /// assert!(esc.is_ascii_control());
     /// ```
     #[stable(feature = "ascii_ctype_on_intrinsics", since = "1.24.0")]
+    #[rustc_const_unstable(feature = "const_ascii_ctype_on_intrinsics", issue = "68983")]
     #[inline]
-    pub fn is_ascii_control(&self) -> bool {
+    pub const fn is_ascii_control(&self) -> bool {
         self.is_ascii() && (*self as u8).is_ascii_control()
     }
 }
diff --git a/src/libcore/lib.rs b/src/libcore/lib.rs
index 1fd70e1a1b0..176c36664a9 100644
--- a/src/libcore/lib.rs
+++ b/src/libcore/lib.rs
@@ -70,6 +70,7 @@
 #![feature(bound_cloned)]
 #![feature(cfg_target_has_atomic)]
 #![feature(concat_idents)]
+#![feature(const_ascii_ctype_on_intrinsics)]
 #![feature(const_alloc_layout)]
 #![feature(const_if_match)]
 #![feature(const_checked_int_methods)]
diff --git a/src/libcore/num/mod.rs b/src/libcore/num/mod.rs
index ed37b48b3e8..787834b7f4f 100644
--- a/src/libcore/num/mod.rs
+++ b/src/libcore/num/mod.rs
@@ -4448,8 +4448,9 @@ impl u8 {
     /// assert!(!esc.is_ascii_alphabetic());
     /// ```
     #[stable(feature = "ascii_ctype_on_intrinsics", since = "1.24.0")]
+    #[rustc_const_unstable(feature = "const_ascii_ctype_on_intrinsics", issue = "68983")]
     #[inline]
-    pub fn is_ascii_alphabetic(&self) -> bool {
+    pub const fn is_ascii_alphabetic(&self) -> bool {
         matches!(*self, b'A'..=b'Z' | b'a'..=b'z')
     }
 
@@ -4480,8 +4481,9 @@ impl u8 {
     /// assert!(!esc.is_ascii_uppercase());
     /// ```
     #[stable(feature = "ascii_ctype_on_intrinsics", since = "1.24.0")]
+    #[rustc_const_unstable(feature = "const_ascii_ctype_on_intrinsics", issue = "68983")]
     #[inline]
-    pub fn is_ascii_uppercase(&self) -> bool {
+    pub const fn is_ascii_uppercase(&self) -> bool {
         matches!(*self, b'A'..=b'Z')
     }
 
@@ -4512,8 +4514,9 @@ impl u8 {
     /// assert!(!esc.is_ascii_lowercase());
     /// ```
     #[stable(feature = "ascii_ctype_on_intrinsics", since = "1.24.0")]
+    #[rustc_const_unstable(feature = "const_ascii_ctype_on_intrinsics", issue = "68983")]
     #[inline]
-    pub fn is_ascii_lowercase(&self) -> bool {
+    pub const fn is_ascii_lowercase(&self) -> bool {
         matches!(*self, b'a'..=b'z')
     }
 
@@ -4547,8 +4550,9 @@ impl u8 {
     /// assert!(!esc.is_ascii_alphanumeric());
     /// ```
     #[stable(feature = "ascii_ctype_on_intrinsics", since = "1.24.0")]
+    #[rustc_const_unstable(feature = "const_ascii_ctype_on_intrinsics", issue = "68983")]
     #[inline]
-    pub fn is_ascii_alphanumeric(&self) -> bool {
+    pub const fn is_ascii_alphanumeric(&self) -> bool {
         matches!(*self, b'0'..=b'9' | b'A'..=b'Z' | b'a'..=b'z')
     }
 
@@ -4579,8 +4583,9 @@ impl u8 {
     /// assert!(!esc.is_ascii_digit());
     /// ```
     #[stable(feature = "ascii_ctype_on_intrinsics", since = "1.24.0")]
+    #[rustc_const_unstable(feature = "const_ascii_ctype_on_intrinsics", issue = "68983")]
     #[inline]
-    pub fn is_ascii_digit(&self) -> bool {
+    pub const fn is_ascii_digit(&self) -> bool {
         matches!(*self, b'0'..=b'9')
     }
 
@@ -4614,8 +4619,9 @@ impl u8 {
     /// assert!(!esc.is_ascii_hexdigit());
     /// ```
     #[stable(feature = "ascii_ctype_on_intrinsics", since = "1.24.0")]
+    #[rustc_const_unstable(feature = "const_ascii_ctype_on_intrinsics", issue = "68983")]
     #[inline]
-    pub fn is_ascii_hexdigit(&self) -> bool {
+    pub const fn is_ascii_hexdigit(&self) -> bool {
         matches!(*self, b'0'..=b'9' | b'A'..=b'F' | b'a'..=b'f')
     }
 
@@ -4650,8 +4656,9 @@ impl u8 {
     /// assert!(!esc.is_ascii_punctuation());
     /// ```
     #[stable(feature = "ascii_ctype_on_intrinsics", since = "1.24.0")]
+    #[rustc_const_unstable(feature = "const_ascii_ctype_on_intrinsics", issue = "68983")]
     #[inline]
-    pub fn is_ascii_punctuation(&self) -> bool {
+    pub const fn is_ascii_punctuation(&self) -> bool {
         matches!(*self, b'!'..=b'/' | b':'..=b'@' | b'['..=b'`' | b'{'..=b'~')
     }
 
@@ -4682,8 +4689,9 @@ impl u8 {
     /// assert!(!esc.is_ascii_graphic());
     /// ```
     #[stable(feature = "ascii_ctype_on_intrinsics", since = "1.24.0")]
+    #[rustc_const_unstable(feature = "const_ascii_ctype_on_intrinsics", issue = "68983")]
     #[inline]
-    pub fn is_ascii_graphic(&self) -> bool {
+    pub const fn is_ascii_graphic(&self) -> bool {
         matches!(*self, b'!'..=b'~')
     }
 
@@ -4731,8 +4739,9 @@ impl u8 {
     /// assert!(!esc.is_ascii_whitespace());
     /// ```
     #[stable(feature = "ascii_ctype_on_intrinsics", since = "1.24.0")]
+    #[rustc_const_unstable(feature = "const_ascii_ctype_on_intrinsics", issue = "68983")]
     #[inline]
-    pub fn is_ascii_whitespace(&self) -> bool {
+    pub const fn is_ascii_whitespace(&self) -> bool {
         matches!(*self, b'\t' | b'\n' | b'\x0C' | b'\r' | b' ')
     }
 
@@ -4765,8 +4774,9 @@ impl u8 {
     /// assert!(esc.is_ascii_control());
     /// ```
     #[stable(feature = "ascii_ctype_on_intrinsics", since = "1.24.0")]
+    #[rustc_const_unstable(feature = "const_ascii_ctype_on_intrinsics", issue = "68983")]
     #[inline]
-    pub fn is_ascii_control(&self) -> bool {
+    pub const fn is_ascii_control(&self) -> bool {
         matches!(*self, b'\0'..=b'\x1F' | b'\x7F')
     }
 }