Auto merge of #74831 - Manishearth:rollup-ugw4pt4, r=Manishearth

Rollup of 4 pull requests

Successful merges:

 - #73858 (Make more primitive integer methods const)
 - #74487 (Forbid generic parameters in anon consts inside of type defaults)
 - #74803 (rustbuild: fix bad usage of UNIX exec() in rustc wrapper)
 - #74822 (More ensure stack to avoid segfault with increased `recursion_limit`)

Failed merges:

r? @ghost

17 files changed, 209 insertions, 94 deletions

diff --git a/src/bootstrap/bin/rustc.rs b/src/bootstrap/bin/rustc.rs
index fd36cd9bd8b..af75faf698e 100644
--- a/src/bootstrap/bin/rustc.rs
+++ b/src/bootstrap/bin/rustc.rs
@@ -153,7 +153,7 @@ fn main() {
             e => e,
         };
         println!("\nDid not run successfully: {:?}\n{:?}\n-------------", e, cmd);
-        exec_cmd(&mut on_fail).expect("could not run the backup command");
+        status_code(&mut on_fail).expect("could not run the backup command");
         std::process::exit(1);
     }
 
@@ -182,17 +182,10 @@ fn main() {
         }
     }
 
-    let code = exec_cmd(&mut cmd).unwrap_or_else(|_| panic!("\n\n failed to run {:?}", cmd));
+    let code = status_code(&mut cmd).unwrap_or_else(|_| panic!("\n\n failed to run {:?}", cmd));
     std::process::exit(code);
 }
 
-#[cfg(unix)]
-fn exec_cmd(cmd: &mut Command) -> io::Result<i32> {
-    use std::os::unix::process::CommandExt;
-    Err(cmd.exec())
-}
-
-#[cfg(not(unix))]
-fn exec_cmd(cmd: &mut Command) -> io::Result<i32> {
+fn status_code(cmd: &mut Command) -> io::Result<i32> {
     cmd.status().map(|status| status.code().unwrap())
 }
diff --git a/src/libcore/char/methods.rs b/src/libcore/char/methods.rs
index 72555d781ed..2603ecf428c 100644
--- a/src/libcore/char/methods.rs
+++ b/src/libcore/char/methods.rs
@@ -1226,7 +1226,7 @@ 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")]
+    #[rustc_const_stable(feature = "const_ascii_ctype_on_intrinsics", since = "1.47.0")]
     #[inline]
     pub const fn is_ascii_alphabetic(&self) -> bool {
         match *self {
@@ -1262,7 +1262,7 @@ 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")]
+    #[rustc_const_stable(feature = "const_ascii_ctype_on_intrinsics", since = "1.47.0")]
     #[inline]
     pub const fn is_ascii_uppercase(&self) -> bool {
         match *self {
@@ -1298,7 +1298,7 @@ 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")]
+    #[rustc_const_stable(feature = "const_ascii_ctype_on_intrinsics", since = "1.47.0")]
     #[inline]
     pub const fn is_ascii_lowercase(&self) -> bool {
         match *self {
@@ -1337,7 +1337,7 @@ 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")]
+    #[rustc_const_stable(feature = "const_ascii_ctype_on_intrinsics", since = "1.47.0")]
     #[inline]
     pub const fn is_ascii_alphanumeric(&self) -> bool {
         match *self {
@@ -1373,7 +1373,7 @@ 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")]
+    #[rustc_const_stable(feature = "const_ascii_ctype_on_intrinsics", since = "1.47.0")]
     #[inline]
     pub const fn is_ascii_digit(&self) -> bool {
         match *self {
@@ -1412,7 +1412,7 @@ 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")]
+    #[rustc_const_stable(feature = "const_ascii_ctype_on_intrinsics", since = "1.47.0")]
     #[inline]
     pub const fn is_ascii_hexdigit(&self) -> bool {
         match *self {
@@ -1452,7 +1452,7 @@ 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")]
+    #[rustc_const_stable(feature = "const_ascii_ctype_on_intrinsics", since = "1.47.0")]
     #[inline]
     pub const fn is_ascii_punctuation(&self) -> bool {
         match *self {
@@ -1488,7 +1488,7 @@ 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")]
+    #[rustc_const_stable(feature = "const_ascii_ctype_on_intrinsics", since = "1.47.0")]
     #[inline]
     pub const fn is_ascii_graphic(&self) -> bool {
         match *self {
@@ -1541,7 +1541,7 @@ 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")]
+    #[rustc_const_stable(feature = "const_ascii_ctype_on_intrinsics", since = "1.47.0")]
     #[inline]
     pub const fn is_ascii_whitespace(&self) -> bool {
         match *self {
@@ -1579,7 +1579,7 @@ 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")]
+    #[rustc_const_stable(feature = "const_ascii_ctype_on_intrinsics", since = "1.47.0")]
     #[inline]
     pub const fn is_ascii_control(&self) -> bool {
         match *self {
diff --git a/src/libcore/lib.rs b/src/libcore/lib.rs
index 2e443064706..edc3fdceb4f 100644
--- a/src/libcore/lib.rs
+++ b/src/libcore/lib.rs
@@ -70,13 +70,11 @@
 #![feature(bound_cloned)]
 #![feature(cfg_target_has_atomic)]
 #![feature(concat_idents)]
-#![feature(const_ascii_ctype_on_intrinsics)]
 #![feature(const_alloc_layout)]
 #![feature(const_discriminant)]
 #![feature(const_checked_int_methods)]
 #![feature(const_euclidean_int_methods)]
 #![feature(const_overflowing_int_methods)]
-#![feature(const_saturating_int_methods)]
 #![feature(const_int_unchecked_arith)]
 #![feature(const_int_pow)]
 #![feature(constctlz)]
diff --git a/src/libcore/num/mod.rs b/src/libcore/num/mod.rs
index 8e9a9035228..048c9c5ddaa 100644
--- a/src/libcore/num/mod.rs
+++ b/src/libcore/num/mod.rs
@@ -87,7 +87,7 @@ assert_eq!(size_of::<Option<core::num::", stringify!($Ty), ">>(), size_of::<", s
 
                 /// Creates a non-zero if the given value is not zero.
                 #[$stability]
-                #[rustc_const_unstable(feature = "const_nonzero_int_methods", issue = "53718")]
+                #[rustc_const_stable(feature = "const_nonzero_int_methods", since = "1.47.0")]
                 #[inline]
                 pub const fn new(n: $Int) -> Option<Self> {
                     if n != 0 {
@@ -747,7 +747,7 @@ assert_eq!((", stringify!($SelfT), "::MAX - 2).checked_add(3), None);",
 $EndFeature, "
 ```"),
             #[stable(feature = "rust1", since = "1.0.0")]
-            #[rustc_const_unstable(feature = "const_checked_int_methods", issue = "53718")]
+            #[rustc_const_stable(feature = "const_checked_int_methods", since = "1.47.0")]
             #[must_use = "this returns the result of the operation, \
                           without modifying the original"]
             #[inline]
@@ -791,7 +791,7 @@ assert_eq!((", stringify!($SelfT), "::MIN + 2).checked_sub(3), None);",
 $EndFeature, "
 ```"),
             #[stable(feature = "rust1", since = "1.0.0")]
-            #[rustc_const_unstable(feature = "const_checked_int_methods", issue = "53718")]
+            #[rustc_const_stable(feature = "const_checked_int_methods", since = "1.47.0")]
             #[must_use = "this returns the result of the operation, \
                           without modifying the original"]
             #[inline]
@@ -835,7 +835,7 @@ assert_eq!(", stringify!($SelfT), "::MAX.checked_mul(2), None);",
 $EndFeature, "
 ```"),
             #[stable(feature = "rust1", since = "1.0.0")]
-            #[rustc_const_unstable(feature = "const_checked_int_methods", issue = "53718")]
+            #[rustc_const_stable(feature = "const_checked_int_methods", since = "1.47.0")]
             #[must_use = "this returns the result of the operation, \
                           without modifying the original"]
             #[inline]
@@ -993,7 +993,7 @@ assert_eq!(", stringify!($SelfT), "::MIN.checked_neg(), None);",
 $EndFeature, "
 ```"),
             #[stable(feature = "wrapping", since = "1.7.0")]
-            #[rustc_const_unstable(feature = "const_checked_int_methods", issue = "53718")]
+            #[rustc_const_stable(feature = "const_checked_int_methods", since = "1.47.0")]
             #[inline]
             pub const fn checked_neg(self) -> Option<Self> {
                 let (a, b) = self.overflowing_neg();
@@ -1015,7 +1015,7 @@ assert_eq!(0x1", stringify!($SelfT), ".checked_shl(129), None);",
 $EndFeature, "
 ```"),
             #[stable(feature = "wrapping", since = "1.7.0")]
-            #[rustc_const_unstable(feature = "const_checked_int_methods", issue = "53718")]
+            #[rustc_const_stable(feature = "const_checked_int_methods", since = "1.47.0")]
             #[must_use = "this returns the result of the operation, \
                           without modifying the original"]
             #[inline]
@@ -1039,7 +1039,7 @@ assert_eq!(0x10", stringify!($SelfT), ".checked_shr(128), None);",
 $EndFeature, "
 ```"),
             #[stable(feature = "wrapping", since = "1.7.0")]
-            #[rustc_const_unstable(feature = "const_checked_int_methods", issue = "53718")]
+            #[rustc_const_stable(feature = "const_checked_int_methods", since = "1.47.0")]
             #[must_use = "this returns the result of the operation, \
                           without modifying the original"]
             #[inline]
@@ -1064,7 +1064,7 @@ assert_eq!(", stringify!($SelfT), "::MIN.checked_abs(), None);",
 $EndFeature, "
 ```"),
             #[stable(feature = "no_panic_abs", since = "1.13.0")]
-            #[rustc_const_unstable(feature = "const_checked_int_methods", issue = "53718")]
+            #[rustc_const_stable(feature = "const_checked_int_methods", since = "1.47.0")]
             #[inline]
             pub const fn checked_abs(self) -> Option<Self> {
                 if self.is_negative() {
@@ -1134,7 +1134,7 @@ $EndFeature, "
 ```"),
 
             #[stable(feature = "rust1", since = "1.0.0")]
-            #[rustc_const_unstable(feature = "const_saturating_int_methods", issue = "53718")]
+            #[rustc_const_stable(feature = "const_saturating_int_methods", since = "1.47.0")]
             #[must_use = "this returns the result of the operation, \
                           without modifying the original"]
             #[inline]
@@ -1160,7 +1160,7 @@ assert_eq!(", stringify!($SelfT), "::MAX.saturating_sub(-1), ", stringify!($Self
 $EndFeature, "
 ```"),
             #[stable(feature = "rust1", since = "1.0.0")]
-            #[rustc_const_unstable(feature = "const_saturating_int_methods", issue = "53718")]
+            #[rustc_const_stable(feature = "const_saturating_int_methods", since = "1.47.0")]
             #[must_use = "this returns the result of the operation, \
                           without modifying the original"]
             #[inline]
@@ -1188,7 +1188,7 @@ $EndFeature, "
 ```"),
 
             #[stable(feature = "saturating_neg", since = "1.45.0")]
-            #[rustc_const_unstable(feature = "const_saturating_int_methods", issue = "53718")]
+            #[rustc_const_stable(feature = "const_saturating_int_methods", since = "1.47.0")]
             #[inline]
             pub const fn saturating_neg(self) -> Self {
                 intrinsics::saturating_sub(0, self)
@@ -1214,7 +1214,7 @@ $EndFeature, "
 ```"),
 
             #[stable(feature = "saturating_neg", since = "1.45.0")]
-            #[rustc_const_unstable(feature = "const_saturating_int_methods", issue = "53718")]
+            #[rustc_const_stable(feature = "const_saturating_int_methods", since = "1.47.0")]
             #[inline]
             pub const fn saturating_abs(self) -> Self {
                 if self.is_negative() {
@@ -1241,7 +1241,7 @@ assert_eq!(", stringify!($SelfT), "::MIN.saturating_mul(10), ", stringify!($Self
 $EndFeature, "
 ```"),
             #[stable(feature = "wrapping", since = "1.7.0")]
-            #[rustc_const_unstable(feature = "const_saturating_int_methods", issue = "53718")]
+            #[rustc_const_stable(feature = "const_saturating_int_methods", since = "1.47.0")]
             #[must_use = "this returns the result of the operation, \
                           without modifying the original"]
             #[inline]
@@ -2203,7 +2203,7 @@ assert_eq!((-10", stringify!($SelfT), ").signum(), -1);",
 $EndFeature, "
 ```"),
             #[stable(feature = "rust1", since = "1.0.0")]
-            #[rustc_const_unstable(feature = "const_int_sign", issue = "53718")]
+            #[rustc_const_stable(feature = "const_int_sign", since = "1.47.0")]
             #[inline]
             pub const fn signum(self) -> Self {
                 match self {
@@ -2985,7 +2985,7 @@ Basic usage:
 assert_eq!((", stringify!($SelfT), "::MAX - 2).checked_add(3), None);", $EndFeature, "
 ```"),
             #[stable(feature = "rust1", since = "1.0.0")]
-            #[rustc_const_unstable(feature = "const_checked_int_methods", issue = "53718")]
+            #[rustc_const_stable(feature = "const_checked_int_methods", since = "1.47.0")]
             #[must_use = "this returns the result of the operation, \
                           without modifying the original"]
             #[inline]
@@ -3027,7 +3027,7 @@ Basic usage:
 assert_eq!(0", stringify!($SelfT), ".checked_sub(1), None);", $EndFeature, "
 ```"),
             #[stable(feature = "rust1", since = "1.0.0")]
-            #[rustc_const_unstable(feature = "const_checked_int_methods", issue = "53718")]
+            #[rustc_const_stable(feature = "const_checked_int_methods", since = "1.47.0")]
             #[must_use = "this returns the result of the operation, \
                           without modifying the original"]
             #[inline]
@@ -3069,7 +3069,7 @@ Basic usage:
 assert_eq!(", stringify!($SelfT), "::MAX.checked_mul(2), None);", $EndFeature, "
 ```"),
             #[stable(feature = "rust1", since = "1.0.0")]
-            #[rustc_const_unstable(feature = "const_checked_int_methods", issue = "53718")]
+            #[rustc_const_stable(feature = "const_checked_int_methods", since = "1.47.0")]
             #[must_use = "this returns the result of the operation, \
                           without modifying the original"]
             #[inline]
@@ -3222,7 +3222,7 @@ Basic usage:
 assert_eq!(1", stringify!($SelfT), ".checked_neg(), None);", $EndFeature, "
 ```"),
             #[stable(feature = "wrapping", since = "1.7.0")]
-            #[rustc_const_unstable(feature = "const_checked_int_methods", issue = "53718")]
+            #[rustc_const_stable(feature = "const_checked_int_methods", since = "1.47.0")]
             #[inline]
             pub const fn checked_neg(self) -> Option<Self> {
                 let (a, b) = self.overflowing_neg();
@@ -3243,7 +3243,7 @@ Basic usage:
 assert_eq!(0x10", stringify!($SelfT), ".checked_shl(129), None);", $EndFeature, "
 ```"),
             #[stable(feature = "wrapping", since = "1.7.0")]
-            #[rustc_const_unstable(feature = "const_checked_int_methods", issue = "53718")]
+            #[rustc_const_stable(feature = "const_checked_int_methods", since = "1.47.0")]
             #[must_use = "this returns the result of the operation, \
                           without modifying the original"]
             #[inline]
@@ -3266,7 +3266,7 @@ Basic usage:
 assert_eq!(0x10", stringify!($SelfT), ".checked_shr(129), None);", $EndFeature, "
 ```"),
             #[stable(feature = "wrapping", since = "1.7.0")]
-            #[rustc_const_unstable(feature = "const_checked_int_methods", issue = "53718")]
+            #[rustc_const_stable(feature = "const_checked_int_methods", since = "1.47.0")]
             #[must_use = "this returns the result of the operation, \
                           without modifying the original"]
             #[inline]
@@ -3334,7 +3334,7 @@ $EndFeature, "
             #[stable(feature = "rust1", since = "1.0.0")]
             #[must_use = "this returns the result of the operation, \
                           without modifying the original"]
-            #[rustc_const_unstable(feature = "const_saturating_int_methods", issue = "53718")]
+            #[rustc_const_stable(feature = "const_saturating_int_methods", since = "1.47.0")]
             #[inline]
             pub const fn saturating_add(self, rhs: Self) -> Self {
                 intrinsics::saturating_add(self, rhs)
@@ -3356,7 +3356,7 @@ assert_eq!(13", stringify!($SelfT), ".saturating_sub(127), 0);", $EndFeature, "
             #[stable(feature = "rust1", since = "1.0.0")]
             #[must_use = "this returns the result of the operation, \
                           without modifying the original"]
-            #[rustc_const_unstable(feature = "const_saturating_int_methods", issue = "53718")]
+            #[rustc_const_stable(feature = "const_saturating_int_methods", since = "1.47.0")]
             #[inline]
             pub const fn saturating_sub(self, rhs: Self) -> Self {
                 intrinsics::saturating_sub(self, rhs)
@@ -3378,7 +3378,7 @@ assert_eq!((", stringify!($SelfT), "::MAX).saturating_mul(10), ", stringify!($Se
 "::MAX);", $EndFeature, "
 ```"),
             #[stable(feature = "wrapping", since = "1.7.0")]
-            #[rustc_const_unstable(feature = "const_saturating_int_methods", issue = "53718")]
+            #[rustc_const_stable(feature = "const_saturating_int_methods", since = "1.47.0")]
             #[must_use = "this returns the result of the operation, \
                           without modifying the original"]
             #[inline]
@@ -4672,7 +4672,7 @@ 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")]
+    #[rustc_const_stable(feature = "const_ascii_ctype_on_intrinsics", since = "1.47.0")]
     #[inline]
     pub const fn is_ascii_alphabetic(&self) -> bool {
         matches!(*self, b'A'..=b'Z' | b'a'..=b'z')
@@ -4705,7 +4705,7 @@ 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")]
+    #[rustc_const_stable(feature = "const_ascii_ctype_on_intrinsics", since = "1.47.0")]
     #[inline]
     pub const fn is_ascii_uppercase(&self) -> bool {
         matches!(*self, b'A'..=b'Z')
@@ -4738,7 +4738,7 @@ 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")]
+    #[rustc_const_stable(feature = "const_ascii_ctype_on_intrinsics", since = "1.47.0")]
     #[inline]
     pub const fn is_ascii_lowercase(&self) -> bool {
         matches!(*self, b'a'..=b'z')
@@ -4774,7 +4774,7 @@ 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")]
+    #[rustc_const_stable(feature = "const_ascii_ctype_on_intrinsics", since = "1.47.0")]
     #[inline]
     pub const fn is_ascii_alphanumeric(&self) -> bool {
         matches!(*self, b'0'..=b'9' | b'A'..=b'Z' | b'a'..=b'z')
@@ -4807,7 +4807,7 @@ 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")]
+    #[rustc_const_stable(feature = "const_ascii_ctype_on_intrinsics", since = "1.47.0")]
     #[inline]
     pub const fn is_ascii_digit(&self) -> bool {
         matches!(*self, b'0'..=b'9')
@@ -4843,7 +4843,7 @@ 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")]
+    #[rustc_const_stable(feature = "const_ascii_ctype_on_intrinsics", since = "1.47.0")]
     #[inline]
     pub const fn is_ascii_hexdigit(&self) -> bool {
         matches!(*self, b'0'..=b'9' | b'A'..=b'F' | b'a'..=b'f')
@@ -4880,7 +4880,7 @@ 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")]
+    #[rustc_const_stable(feature = "const_ascii_ctype_on_intrinsics", since = "1.47.0")]
     #[inline]
     pub const fn is_ascii_punctuation(&self) -> bool {
         matches!(*self, b'!'..=b'/' | b':'..=b'@' | b'['..=b'`' | b'{'..=b'~')
@@ -4913,7 +4913,7 @@ 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")]
+    #[rustc_const_stable(feature = "const_ascii_ctype_on_intrinsics", since = "1.47.0")]
     #[inline]
     pub const fn is_ascii_graphic(&self) -> bool {
         matches!(*self, b'!'..=b'~')
@@ -4963,7 +4963,7 @@ 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")]
+    #[rustc_const_stable(feature = "const_ascii_ctype_on_intrinsics", since = "1.47.0")]
     #[inline]
     pub const fn is_ascii_whitespace(&self) -> bool {
         matches!(*self, b'\t' | b'\n' | b'\x0C' | b'\r' | b' ')
@@ -4998,7 +4998,7 @@ 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")]
+    #[rustc_const_stable(feature = "const_ascii_ctype_on_intrinsics", since = "1.47.0")]
     #[inline]
     pub const fn is_ascii_control(&self) -> bool {
         matches!(*self, b'\0'..=b'\x1F' | b'\x7F')
diff --git a/src/librustc_resolve/diagnostics.rs b/src/librustc_resolve/diagnostics.rs
index a7a005bdeb9..81e29047dc5 100644
--- a/src/librustc_resolve/diagnostics.rs
+++ b/src/librustc_resolve/diagnostics.rs
@@ -442,7 +442,7 @@ impl<'a> Resolver<'a> {
                 );
                 err
             }
-            ResolutionError::ParamInTyOfConstArg(name) => {
+            ResolutionError::ParamInTyOfConstParam(name) => {
                 let mut err = struct_span_err!(
                     self.session,
                     span,
@@ -455,6 +455,17 @@ impl<'a> Resolver<'a> {
                 );
                 err
             }
+            ResolutionError::ParamInAnonConstInTyDefault(name) => {
+                let mut err = self.session.struct_span_err(
+                    span,
+                    "constant values inside of type parameter defaults must not depend on generic parameters",
+                );
+                err.span_label(
+                    span,
+                    format!("the anonymous constant must not depend on the parameter `{}`", name),
+                );
+                err
+            }
             ResolutionError::SelfInTyParamDefault => {
                 let mut err = struct_span_err!(
                     self.session,
diff --git a/src/librustc_resolve/late.rs b/src/librustc_resolve/late.rs
index 4b5ab03df43..bcd2c6c1f1c 100644
--- a/src/librustc_resolve/late.rs
+++ b/src/librustc_resolve/late.rs
@@ -570,7 +570,15 @@ impl<'a, 'ast> Visitor<'ast> for LateResolutionVisitor<'a, '_, 'ast> {
 
                     if let Some(ref ty) = default {
                         self.ribs[TypeNS].push(default_ban_rib);
-                        self.visit_ty(ty);
+                        self.with_rib(ValueNS, ForwardTyParamBanRibKind, |this| {
+                            // HACK: We use an empty `ForwardTyParamBanRibKind` here which
+                            // is only used to forbid the use of const parameters inside of
+                            // type defaults.
+                            //
+                            // While the rib name doesn't really fit here, it does allow us to use the same
+                            // code for both const and type parameters.
+                            this.visit_ty(ty);
+                        });
                         default_ban_rib = self.ribs[TypeNS].pop().unwrap();
                     }
 
@@ -1081,7 +1089,9 @@ impl<'a, 'b, 'ast> LateResolutionVisitor<'a, 'b, 'ast> {
     fn with_constant_rib(&mut self, f: impl FnOnce(&mut Self)) {
         debug!("with_constant_rib");
         self.with_rib(ValueNS, ConstantItemRibKind, |this| {
-            this.with_label_rib(ConstantItemRibKind, f);
+            this.with_rib(TypeNS, ConstantItemRibKind, |this| {
+                this.with_label_rib(ConstantItemRibKind, f);
+            })
         });
     }
 
diff --git a/src/librustc_resolve/lib.rs b/src/librustc_resolve/lib.rs
index dfc50a30c12..234fcd789ee 100644
--- a/src/librustc_resolve/lib.rs
+++ b/src/librustc_resolve/lib.rs
@@ -215,7 +215,9 @@ enum ResolutionError<'a> {
     /// Error E0128: type parameters with a default cannot use forward-declared identifiers.
     ForwardDeclaredTyParam, // FIXME(const_generics:defaults)
     /// ERROR E0770: the type of const parameters must not depend on other generic parameters.
-    ParamInTyOfConstArg(Symbol),
+    ParamInTyOfConstParam(Symbol),
+    /// constant values inside of type parameter defaults must not depend on generic parameters.
+    ParamInAnonConstInTyDefault(Symbol),
     /// Error E0735: type parameters with a default cannot use `Self`
     SelfInTyParamDefault,
     /// Error E0767: use of unreachable label
@@ -2514,7 +2516,7 @@ impl<'a> Resolver<'a> {
                         }
                         ConstParamTyRibKind => {
                             if record_used {
-                                self.report_error(span, ParamInTyOfConstArg(rib_ident.name));
+                                self.report_error(span, ParamInTyOfConstParam(rib_ident.name));
                             }
                             return Res::Err;
                         }
@@ -2526,18 +2528,40 @@ impl<'a> Resolver<'a> {
                 }
             }
             Res::Def(DefKind::TyParam, _) | Res::SelfTy(..) => {
+                let mut in_ty_param_default = false;
                 for rib in ribs {
                     let has_generic_params = match rib.kind {
                         NormalRibKind
                         | ClosureOrAsyncRibKind
                         | AssocItemRibKind
                         | ModuleRibKind(..)
-                        | MacroDefinition(..)
-                        | ForwardTyParamBanRibKind
-                        | ConstantItemRibKind => {
+                        | MacroDefinition(..) => {
                             // Nothing to do. Continue.
                             continue;
                         }
+
+                        // We only forbid constant items if we are inside of type defaults,
+                        // for example `struct Foo<T, U = [u8; std::mem::size_of::<T>()]>`
+                        ForwardTyParamBanRibKind => {
+                            in_ty_param_default = true;
+                            continue;
+                        }
+                        ConstantItemRibKind => {
+                            if in_ty_param_default {
+                                if record_used {
+                                    self.report_error(
+                                        span,
+                                        ResolutionError::ParamInAnonConstInTyDefault(
+                                            rib_ident.name,
+                                        ),
+                                    );
+                                }
+                                return Res::Err;
+                            } else {
+                                continue;
+                            }
+                        }
+
                         // This was an attempt to use a type parameter outside its scope.
                         ItemRibKind(has_generic_params) => has_generic_params,
                         FnItemRibKind => HasGenericParams::Yes,
@@ -2545,7 +2569,7 @@ impl<'a> Resolver<'a> {
                             if record_used {
                                 self.report_error(
                                     span,
-                                    ResolutionError::ParamInTyOfConstArg(rib_ident.name),
+                                    ResolutionError::ParamInTyOfConstParam(rib_ident.name),
                                 );
                             }
                             return Res::Err;
@@ -2572,22 +2596,45 @@ impl<'a> Resolver<'a> {
                     // (spuriously) conflicting with the const param.
                     ribs.next();
                 }
+
+                let mut in_ty_param_default = false;
                 for rib in ribs {
                     let has_generic_params = match rib.kind {
                         NormalRibKind
                         | ClosureOrAsyncRibKind
                         | AssocItemRibKind
                         | ModuleRibKind(..)
-                        | MacroDefinition(..)
-                        | ForwardTyParamBanRibKind
-                        | ConstantItemRibKind => continue,
+                        | MacroDefinition(..) => continue,
+
+                        // We only forbid constant items if we are inside of type defaults,
+                        // for example `struct Foo<T, U = [u8; std::mem::size_of::<T>()]>`
+                        ForwardTyParamBanRibKind => {
+                            in_ty_param_default = true;
+                            continue;
+                        }
+                        ConstantItemRibKind => {
+                            if in_ty_param_default {
+                                if record_used {
+                                    self.report_error(
+                                        span,
+                                        ResolutionError::ParamInAnonConstInTyDefault(
+                                            rib_ident.name,
+                                        ),
+                                    );
+                                }
+                                return Res::Err;
+                            } else {
+                                continue;
+                            }
+                        }
+
                         ItemRibKind(has_generic_params) => has_generic_params,
                         FnItemRibKind => HasGenericParams::Yes,
                         ConstParamTyRibKind => {
                             if record_used {
                                 self.report_error(
                                     span,
-                                    ResolutionError::ParamInTyOfConstArg(rib_ident.name),
+                                    ResolutionError::ParamInTyOfConstParam(rib_ident.name),
                                 );
                             }
                             return Res::Err;
diff --git a/src/librustc_trait_selection/traits/error_reporting/suggestions.rs b/src/librustc_trait_selection/traits/error_reporting/suggestions.rs
index 0632ce2319a..432abee6d1c 100644
--- a/src/librustc_trait_selection/traits/error_reporting/suggestions.rs
+++ b/src/librustc_trait_selection/traits/error_reporting/suggestions.rs
@@ -7,6 +7,7 @@ use crate::autoderef::Autoderef;
 use crate::infer::InferCtxt;
 use crate::traits::normalize_projection_type;
 
+use rustc_data_structures::stack::ensure_sufficient_stack;
 use rustc_errors::{error_code, struct_span_err, Applicability, DiagnosticBuilder, Style};
 use rustc_hir as hir;
 use rustc_hir::def::DefKind;
@@ -1912,12 +1913,15 @@ impl<'a, 'tcx> InferCtxtExt<'tcx> for InferCtxt<'a, 'tcx> {
 
                 let parent_predicate = parent_trait_ref.without_const().to_predicate(tcx);
                 if !self.is_recursive_obligation(obligated_types, &data.parent_code) {
-                    self.note_obligation_cause_code(
-                        err,
-                        &parent_predicate,
-                        &data.parent_code,
-                        obligated_types,
-                    );
+                    // #74711: avoid a stack overflow
+                    ensure_sufficient_stack(|| {
+                        self.note_obligation_cause_code(
+                            err,
+                            &parent_predicate,
+                            &data.parent_code,
+                            obligated_types,
+                        )
+                    });
                 }
             }
             ObligationCauseCode::ImplDerivedObligation(ref data) => {
@@ -1928,22 +1932,28 @@ impl<'a, 'tcx> InferCtxtExt<'tcx> for InferCtxt<'a, 'tcx> {
                     parent_trait_ref.skip_binder().self_ty()
                 ));
                 let parent_predicate = parent_trait_ref.without_const().to_predicate(tcx);
-                self.note_obligation_cause_code(
-                    err,
-                    &parent_predicate,
-                    &data.parent_code,
-                    obligated_types,
-                );
+                // #74711: avoid a stack overflow
+                ensure_sufficient_stack(|| {
+                    self.note_obligation_cause_code(
+                        err,
+                        &parent_predicate,
+                        &data.parent_code,
+                        obligated_types,
+                    )
+                });
             }
             ObligationCauseCode::DerivedObligation(ref data) => {
                 let parent_trait_ref = self.resolve_vars_if_possible(&data.parent_trait_ref);
                 let parent_predicate = parent_trait_ref.without_const().to_predicate(tcx);
-                self.note_obligation_cause_code(
-                    err,
-                    &parent_predicate,
-                    &data.parent_code,
-                    obligated_types,
-                );
+                // #74711: avoid a stack overflow
+                ensure_sufficient_stack(|| {
+                    self.note_obligation_cause_code(
+                        err,
+                        &parent_predicate,
+                        &data.parent_code,
+                        obligated_types,
+                    )
+                });
             }
             ObligationCauseCode::CompareImplMethodObligation { .. } => {
                 err.note(&format!(
diff --git a/src/test/ui/const-generics/params-in-ct-in-ty-param-lazy-norm.rs b/src/test/ui/const-generics/params-in-ct-in-ty-param-lazy-norm.rs
new file mode 100644
index 00000000000..84bbea5b880
--- /dev/null
+++ b/src/test/ui/const-generics/params-in-ct-in-ty-param-lazy-norm.rs
@@ -0,0 +1,11 @@
+#![feature(const_generics)] //~ WARN the feature `const_generics` is incomplete
+
+struct Foo<T, U = [u8; std::mem::size_of::<T>()]>(T, U);
+//~^ ERROR constant values inside of type parameter defaults
+
+// FIXME(const_generics:defaults): We still don't know how to we deal with type defaults.
+struct Bar<T = [u8; N], const N: usize>(T);
+//~^ ERROR constant values inside of type parameter defaults
+//~| ERROR type parameters with a default
+
+fn main() {}
diff --git a/src/test/ui/const-generics/params-in-ct-in-ty-param-lazy-norm.stderr b/src/test/ui/const-generics/params-in-ct-in-ty-param-lazy-norm.stderr
new file mode 100644
index 00000000000..571be91683b
--- /dev/null
+++ b/src/test/ui/const-generics/params-in-ct-in-ty-param-lazy-norm.stderr
@@ -0,0 +1,31 @@
+error: type parameters with a default must be trailing
+  --> $DIR/params-in-ct-in-ty-param-lazy-norm.rs:7:12
+   |
+LL | struct Bar<T = [u8; N], const N: usize>(T);
+   |            ^
+   |
+   = note: using type defaults and const parameters in the same parameter list is currently not permitted
+
+error: constant values inside of type parameter defaults must not depend on generic parameters
+  --> $DIR/params-in-ct-in-ty-param-lazy-norm.rs:3:44
+   |
+LL | struct Foo<T, U = [u8; std::mem::size_of::<T>()]>(T, U);
+   |                                            ^ the anonymous constant must not depend on the parameter `T`
+
+error: constant values inside of type parameter defaults must not depend on generic parameters
+  --> $DIR/params-in-ct-in-ty-param-lazy-norm.rs:7:21
+   |
+LL | struct Bar<T = [u8; N], const N: usize>(T);
+   |                     ^ the anonymous constant must not depend on the parameter `N`
+
+warning: the feature `const_generics` is incomplete and may not be safe to use and/or cause compiler crashes
+  --> $DIR/params-in-ct-in-ty-param-lazy-norm.rs:1:12
+   |
+LL | #![feature(const_generics)]
+   |            ^^^^^^^^^^^^^^
+   |
+   = note: `#[warn(incomplete_features)]` on by default
+   = note: see issue #44580 <https://github.com/rust-lang/rust/issues/44580> for more information
+
+error: aborting due to 3 previous errors; 1 warning emitted
+
diff --git a/src/test/ui/consts/ascii_ctype.rs b/src/test/ui/consts/ascii_ctype.rs
index 25b270ee49c..ef2f7322f27 100644
--- a/src/test/ui/consts/ascii_ctype.rs
+++ b/src/test/ui/consts/ascii_ctype.rs
@@ -1,7 +1,5 @@
 // run-pass
 
-#![feature(const_ascii_ctype_on_intrinsics)]
-
 macro_rules! suite {
     ( $( $fn:ident => [$a:ident, $A:ident, $nine:ident, $dot:ident, $space:ident]; )* ) => {
         $(
diff --git a/src/test/ui/consts/const-int-arithmetic.rs b/src/test/ui/consts/const-int-arithmetic.rs
index 9c94551f744..9b2e30961aa 100644
--- a/src/test/ui/consts/const-int-arithmetic.rs
+++ b/src/test/ui/consts/const-int-arithmetic.rs
@@ -3,7 +3,6 @@
 #![feature(const_checked_int_methods)]
 #![feature(const_euclidean_int_methods)]
 #![feature(const_overflowing_int_methods)]
-#![feature(const_saturating_int_methods)]
 #![feature(const_wrapping_int_methods)]
 
 use std::{i8, i128};
diff --git a/src/test/ui/consts/const-int-saturating-arith.rs b/src/test/ui/consts/const-int-saturating-arith.rs
index 4718120a51b..7edbdd4cec5 100644
--- a/src/test/ui/consts/const-int-saturating-arith.rs
+++ b/src/test/ui/consts/const-int-saturating-arith.rs
@@ -1,5 +1,4 @@
 // run-pass
-#![feature(const_saturating_int_methods)]
 
 const INT_U32_NO: u32 = (42 as u32).saturating_add(2);
 const INT_U32: u32 = u32::MAX.saturating_add(1);
diff --git a/src/test/ui/consts/const-int-sign-rpass.rs b/src/test/ui/consts/const-int-sign-rpass.rs
index dc46fce39a9..63c191d4227 100644
--- a/src/test/ui/consts/const-int-sign-rpass.rs
+++ b/src/test/ui/consts/const-int-sign-rpass.rs
@@ -1,7 +1,5 @@
 // run-pass
 
-#![feature(const_int_sign)]
-
 const NEGATIVE_A: bool = (-10i32).is_negative();
 const NEGATIVE_B: bool = 10i32.is_negative();
 const POSITIVE_A: bool = (-10i32).is_positive();
diff --git a/src/test/ui/consts/const-nonzero.rs b/src/test/ui/consts/const-nonzero.rs
index 2160bad4807..cf6f8c8d69a 100644
--- a/src/test/ui/consts/const-nonzero.rs
+++ b/src/test/ui/consts/const-nonzero.rs
@@ -1,7 +1,5 @@
 // run-pass
 
-#![feature(const_nonzero_int_methods)]
-
 use std::num::NonZeroU8;
 
 const X: NonZeroU8 = unsafe { NonZeroU8::new_unchecked(5) };
diff --git a/src/test/ui/generic/param-in-ct-in-ty-param-default.rs b/src/test/ui/generic/param-in-ct-in-ty-param-default.rs
new file mode 100644
index 00000000000..dd89bc0f7a0
--- /dev/null
+++ b/src/test/ui/generic/param-in-ct-in-ty-param-default.rs
@@ -0,0 +1,4 @@
+struct Foo<T, U = [u8; std::mem::size_of::<T>()]>(T, U);
+//~^ ERROR constant values inside of type parameter defaults
+
+fn main() {}
diff --git a/src/test/ui/generic/param-in-ct-in-ty-param-default.stderr b/src/test/ui/generic/param-in-ct-in-ty-param-default.stderr
new file mode 100644
index 00000000000..ea867240269
--- /dev/null
+++ b/src/test/ui/generic/param-in-ct-in-ty-param-default.stderr
@@ -0,0 +1,8 @@
+error: constant values inside of type parameter defaults must not depend on generic parameters
+  --> $DIR/param-in-ct-in-ty-param-default.rs:1:44
+   |
+LL | struct Foo<T, U = [u8; std::mem::size_of::<T>()]>(T, U);
+   |                                            ^ the anonymous constant must not depend on the parameter `T`
+
+error: aborting due to previous error
+