diff --git a/compiler/rustc_llvm/llvm-wrapper/PassWrapper.cpp b/compiler/rustc_llvm/llvm-wrapper/PassWrapper.cpp
index 09f377d349f45..879a3b660b4be 100644
--- a/compiler/rustc_llvm/llvm-wrapper/PassWrapper.cpp
+++ b/compiler/rustc_llvm/llvm-wrapper/PassWrapper.cpp
@@ -1044,7 +1044,7 @@ extern "C" void LLVMRustSetModulePIELevel(LLVMModuleRef M) {
 extern "C" void LLVMRustSetModuleCodeModel(LLVMModuleRef M,
                                            LLVMRustCodeModel Model) {
   auto CM = fromRust(Model);
-  if (!CM.hasValue())
+  if (!CM)
     return;
   unwrap(M)->setCodeModel(*CM);
 }
diff --git a/compiler/rustc_session/src/parse.rs b/compiler/rustc_session/src/parse.rs
index b9202af2a6765..aaf265ad7c336 100644
--- a/compiler/rustc_session/src/parse.rs
+++ b/compiler/rustc_session/src/parse.rs
@@ -376,8 +376,6 @@ impl ParseSess {
     }
 
     #[rustc_lint_diagnostics]
-    #[allow(rustc::diagnostic_outside_of_impl)]
-    #[allow(rustc::untranslatable_diagnostic)]
     pub fn struct_err(
         &self,
         msg: impl Into<DiagnosticMessage>,
@@ -386,22 +384,16 @@ impl ParseSess {
     }
 
     #[rustc_lint_diagnostics]
-    #[allow(rustc::diagnostic_outside_of_impl)]
-    #[allow(rustc::untranslatable_diagnostic)]
     pub fn struct_warn(&self, msg: impl Into<DiagnosticMessage>) -> DiagnosticBuilder<'_, ()> {
         self.span_diagnostic.struct_warn(msg)
     }
 
     #[rustc_lint_diagnostics]
-    #[allow(rustc::diagnostic_outside_of_impl)]
-    #[allow(rustc::untranslatable_diagnostic)]
     pub fn struct_fatal(&self, msg: impl Into<DiagnosticMessage>) -> DiagnosticBuilder<'_, !> {
         self.span_diagnostic.struct_fatal(msg)
     }
 
     #[rustc_lint_diagnostics]
-    #[allow(rustc::diagnostic_outside_of_impl)]
-    #[allow(rustc::untranslatable_diagnostic)]
     pub fn struct_diagnostic<G: EmissionGuarantee>(
         &self,
         msg: impl Into<DiagnosticMessage>,
diff --git a/compiler/rustc_session/src/session.rs b/compiler/rustc_session/src/session.rs
index 0142e98176633..59b544ce9eb83 100644
--- a/compiler/rustc_session/src/session.rs
+++ b/compiler/rustc_session/src/session.rs
@@ -288,8 +288,6 @@ impl Session {
     }
 
     #[rustc_lint_diagnostics]
-    #[allow(rustc::untranslatable_diagnostic)]
-    #[allow(rustc::diagnostic_outside_of_impl)]
     pub fn struct_span_warn<S: Into<MultiSpan>>(
         &self,
         sp: S,
@@ -298,8 +296,6 @@ impl Session {
         self.diagnostic().struct_span_warn(sp, msg)
     }
     #[rustc_lint_diagnostics]
-    #[allow(rustc::untranslatable_diagnostic)]
-    #[allow(rustc::diagnostic_outside_of_impl)]
     pub fn struct_span_warn_with_expectation<S: Into<MultiSpan>>(
         &self,
         sp: S,
@@ -309,8 +305,6 @@ impl Session {
         self.diagnostic().struct_span_warn_with_expectation(sp, msg, id)
     }
     #[rustc_lint_diagnostics]
-    #[allow(rustc::untranslatable_diagnostic)]
-    #[allow(rustc::diagnostic_outside_of_impl)]
     pub fn struct_span_warn_with_code<S: Into<MultiSpan>>(
         &self,
         sp: S,
@@ -320,14 +314,10 @@ impl Session {
         self.diagnostic().struct_span_warn_with_code(sp, msg, code)
     }
     #[rustc_lint_diagnostics]
-    #[allow(rustc::untranslatable_diagnostic)]
-    #[allow(rustc::diagnostic_outside_of_impl)]
     pub fn struct_warn(&self, msg: impl Into<DiagnosticMessage>) -> DiagnosticBuilder<'_, ()> {
         self.diagnostic().struct_warn(msg)
     }
     #[rustc_lint_diagnostics]
-    #[allow(rustc::untranslatable_diagnostic)]
-    #[allow(rustc::diagnostic_outside_of_impl)]
     pub fn struct_warn_with_expectation(
         &self,
         msg: impl Into<DiagnosticMessage>,
@@ -336,8 +326,6 @@ impl Session {
         self.diagnostic().struct_warn_with_expectation(msg, id)
     }
     #[rustc_lint_diagnostics]
-    #[allow(rustc::untranslatable_diagnostic)]
-    #[allow(rustc::diagnostic_outside_of_impl)]
     pub fn struct_span_allow<S: Into<MultiSpan>>(
         &self,
         sp: S,
@@ -346,14 +334,10 @@ impl Session {
         self.diagnostic().struct_span_allow(sp, msg)
     }
     #[rustc_lint_diagnostics]
-    #[allow(rustc::untranslatable_diagnostic)]
-    #[allow(rustc::diagnostic_outside_of_impl)]
     pub fn struct_allow(&self, msg: impl Into<DiagnosticMessage>) -> DiagnosticBuilder<'_, ()> {
         self.diagnostic().struct_allow(msg)
     }
     #[rustc_lint_diagnostics]
-    #[allow(rustc::untranslatable_diagnostic)]
-    #[allow(rustc::diagnostic_outside_of_impl)]
     pub fn struct_expect(
         &self,
         msg: impl Into<DiagnosticMessage>,
@@ -362,8 +346,6 @@ impl Session {
         self.diagnostic().struct_expect(msg, id)
     }
     #[rustc_lint_diagnostics]
-    #[allow(rustc::untranslatable_diagnostic)]
-    #[allow(rustc::diagnostic_outside_of_impl)]
     pub fn struct_span_err<S: Into<MultiSpan>>(
         &self,
         sp: S,
@@ -372,8 +354,6 @@ impl Session {
         self.diagnostic().struct_span_err(sp, msg)
     }
     #[rustc_lint_diagnostics]
-    #[allow(rustc::untranslatable_diagnostic)]
-    #[allow(rustc::diagnostic_outside_of_impl)]
     pub fn struct_span_err_with_code<S: Into<MultiSpan>>(
         &self,
         sp: S,
@@ -384,8 +364,6 @@ impl Session {
     }
     // FIXME: This method should be removed (every error should have an associated error code).
     #[rustc_lint_diagnostics]
-    #[allow(rustc::untranslatable_diagnostic)]
-    #[allow(rustc::diagnostic_outside_of_impl)]
     pub fn struct_err(
         &self,
         msg: impl Into<DiagnosticMessage>,
@@ -393,8 +371,6 @@ impl Session {
         self.parse_sess.struct_err(msg)
     }
     #[rustc_lint_diagnostics]
-    #[allow(rustc::untranslatable_diagnostic)]
-    #[allow(rustc::diagnostic_outside_of_impl)]
     pub fn struct_err_with_code(
         &self,
         msg: impl Into<DiagnosticMessage>,
@@ -403,8 +379,6 @@ impl Session {
         self.diagnostic().struct_err_with_code(msg, code)
     }
     #[rustc_lint_diagnostics]
-    #[allow(rustc::untranslatable_diagnostic)]
-    #[allow(rustc::diagnostic_outside_of_impl)]
     pub fn struct_warn_with_code(
         &self,
         msg: impl Into<DiagnosticMessage>,
@@ -413,8 +387,6 @@ impl Session {
         self.diagnostic().struct_warn_with_code(msg, code)
     }
     #[rustc_lint_diagnostics]
-    #[allow(rustc::untranslatable_diagnostic)]
-    #[allow(rustc::diagnostic_outside_of_impl)]
     pub fn struct_span_fatal<S: Into<MultiSpan>>(
         &self,
         sp: S,
@@ -423,8 +395,6 @@ impl Session {
         self.diagnostic().struct_span_fatal(sp, msg)
     }
     #[rustc_lint_diagnostics]
-    #[allow(rustc::untranslatable_diagnostic)]
-    #[allow(rustc::diagnostic_outside_of_impl)]
     pub fn struct_span_fatal_with_code<S: Into<MultiSpan>>(
         &self,
         sp: S,
@@ -434,21 +404,15 @@ impl Session {
         self.diagnostic().struct_span_fatal_with_code(sp, msg, code)
     }
     #[rustc_lint_diagnostics]
-    #[allow(rustc::untranslatable_diagnostic)]
-    #[allow(rustc::diagnostic_outside_of_impl)]
     pub fn struct_fatal(&self, msg: impl Into<DiagnosticMessage>) -> DiagnosticBuilder<'_, !> {
         self.diagnostic().struct_fatal(msg)
     }
 
     #[rustc_lint_diagnostics]
-    #[allow(rustc::untranslatable_diagnostic)]
-    #[allow(rustc::diagnostic_outside_of_impl)]
     pub fn span_fatal<S: Into<MultiSpan>>(&self, sp: S, msg: impl Into<DiagnosticMessage>) -> ! {
         self.diagnostic().span_fatal(sp, msg)
     }
     #[rustc_lint_diagnostics]
-    #[allow(rustc::untranslatable_diagnostic)]
-    #[allow(rustc::diagnostic_outside_of_impl)]
     pub fn span_fatal_with_code<S: Into<MultiSpan>>(
         &self,
         sp: S,
@@ -458,14 +422,10 @@ impl Session {
         self.diagnostic().span_fatal_with_code(sp, msg, code)
     }
     #[rustc_lint_diagnostics]
-    #[allow(rustc::untranslatable_diagnostic)]
-    #[allow(rustc::diagnostic_outside_of_impl)]
     pub fn fatal(&self, msg: impl Into<DiagnosticMessage>) -> ! {
         self.diagnostic().fatal(msg).raise()
     }
     #[rustc_lint_diagnostics]
-    #[allow(rustc::untranslatable_diagnostic)]
-    #[allow(rustc::diagnostic_outside_of_impl)]
     pub fn span_err_or_warn<S: Into<MultiSpan>>(
         &self,
         is_warning: bool,
@@ -479,8 +439,6 @@ impl Session {
         }
     }
     #[rustc_lint_diagnostics]
-    #[allow(rustc::untranslatable_diagnostic)]
-    #[allow(rustc::diagnostic_outside_of_impl)]
     pub fn span_err<S: Into<MultiSpan>>(
         &self,
         sp: S,
@@ -489,8 +447,6 @@ impl Session {
         self.diagnostic().span_err(sp, msg)
     }
     #[rustc_lint_diagnostics]
-    #[allow(rustc::untranslatable_diagnostic)]
-    #[allow(rustc::diagnostic_outside_of_impl)]
     pub fn span_err_with_code<S: Into<MultiSpan>>(
         &self,
         sp: S,
diff --git a/library/core/src/lib.rs b/library/core/src/lib.rs
index 5690b5256e88c..c3df0d4f9b91a 100644
--- a/library/core/src/lib.rs
+++ b/library/core/src/lib.rs
@@ -195,7 +195,6 @@
 #![feature(link_llvm_intrinsics)]
 #![feature(macro_metavar_expr)]
 #![feature(min_specialization)]
-#![feature(mixed_integer_ops)]
 #![feature(must_not_suspend)]
 #![feature(negative_impls)]
 #![feature(never_type)]
diff --git a/library/core/src/num/int_macros.rs b/library/core/src/num/int_macros.rs
index e7deb728d15d8..d6aeee299e30d 100644
--- a/library/core/src/num/int_macros.rs
+++ b/library/core/src/num/int_macros.rs
@@ -464,12 +464,11 @@ macro_rules! int_impl {
         /// Basic usage:
         ///
         /// ```
-        /// # #![feature(mixed_integer_ops)]
         #[doc = concat!("assert_eq!(1", stringify!($SelfT), ".checked_add_unsigned(2), Some(3));")]
         #[doc = concat!("assert_eq!((", stringify!($SelfT), "::MAX - 2).checked_add_unsigned(3), None);")]
         /// ```
-        #[unstable(feature = "mixed_integer_ops", issue = "87840")]
-        #[rustc_const_unstable(feature = "mixed_integer_ops", issue = "87840")]
+        #[stable(feature = "mixed_integer_ops", since = "CURRENT_RUSTC_VERSION")]
+        #[rustc_const_stable(feature = "mixed_integer_ops", since = "CURRENT_RUSTC_VERSION")]
         #[must_use = "this returns the result of the operation, \
                       without modifying the original"]
         #[inline]
@@ -533,12 +532,11 @@ macro_rules! int_impl {
         /// Basic usage:
         ///
         /// ```
-        /// # #![feature(mixed_integer_ops)]
         #[doc = concat!("assert_eq!(1", stringify!($SelfT), ".checked_sub_unsigned(2), Some(-1));")]
         #[doc = concat!("assert_eq!((", stringify!($SelfT), "::MIN + 2).checked_sub_unsigned(3), None);")]
         /// ```
-        #[unstable(feature = "mixed_integer_ops", issue = "87840")]
-        #[rustc_const_unstable(feature = "mixed_integer_ops", issue = "87840")]
+        #[stable(feature = "mixed_integer_ops", since = "CURRENT_RUSTC_VERSION")]
+        #[rustc_const_stable(feature = "mixed_integer_ops", since = "CURRENT_RUSTC_VERSION")]
         #[must_use = "this returns the result of the operation, \
                       without modifying the original"]
         #[inline]
@@ -907,12 +905,11 @@ macro_rules! int_impl {
         /// Basic usage:
         ///
         /// ```
-        /// # #![feature(mixed_integer_ops)]
         #[doc = concat!("assert_eq!(1", stringify!($SelfT), ".saturating_add_unsigned(2), 3);")]
         #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MAX.saturating_add_unsigned(100), ", stringify!($SelfT), "::MAX);")]
         /// ```
-        #[unstable(feature = "mixed_integer_ops", issue = "87840")]
-        #[rustc_const_unstable(feature = "mixed_integer_ops", issue = "87840")]
+        #[stable(feature = "mixed_integer_ops", since = "CURRENT_RUSTC_VERSION")]
+        #[rustc_const_stable(feature = "mixed_integer_ops", since = "CURRENT_RUSTC_VERSION")]
         #[must_use = "this returns the result of the operation, \
                       without modifying the original"]
         #[inline]
@@ -954,12 +951,11 @@ macro_rules! int_impl {
         /// Basic usage:
         ///
         /// ```
-        /// # #![feature(mixed_integer_ops)]
         #[doc = concat!("assert_eq!(100", stringify!($SelfT), ".saturating_sub_unsigned(127), -27);")]
         #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MIN.saturating_sub_unsigned(100), ", stringify!($SelfT), "::MIN);")]
         /// ```
-        #[unstable(feature = "mixed_integer_ops", issue = "87840")]
-        #[rustc_const_unstable(feature = "mixed_integer_ops", issue = "87840")]
+        #[stable(feature = "mixed_integer_ops", since = "CURRENT_RUSTC_VERSION")]
+        #[rustc_const_stable(feature = "mixed_integer_ops", since = "CURRENT_RUSTC_VERSION")]
         #[must_use = "this returns the result of the operation, \
                       without modifying the original"]
         #[inline]
@@ -1135,12 +1131,11 @@ macro_rules! int_impl {
         /// Basic usage:
         ///
         /// ```
-        /// # #![feature(mixed_integer_ops)]
         #[doc = concat!("assert_eq!(100", stringify!($SelfT), ".wrapping_add_unsigned(27), 127);")]
         #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MAX.wrapping_add_unsigned(2), ", stringify!($SelfT), "::MIN + 1);")]
         /// ```
-        #[unstable(feature = "mixed_integer_ops", issue = "87840")]
-        #[rustc_const_unstable(feature = "mixed_integer_ops", issue = "87840")]
+        #[stable(feature = "mixed_integer_ops", since = "CURRENT_RUSTC_VERSION")]
+        #[rustc_const_stable(feature = "mixed_integer_ops", since = "CURRENT_RUSTC_VERSION")]
         #[must_use = "this returns the result of the operation, \
                       without modifying the original"]
         #[inline(always)]
@@ -1176,12 +1171,11 @@ macro_rules! int_impl {
         /// Basic usage:
         ///
         /// ```
-        /// # #![feature(mixed_integer_ops)]
         #[doc = concat!("assert_eq!(0", stringify!($SelfT), ".wrapping_sub_unsigned(127), -127);")]
         #[doc = concat!("assert_eq!((-2", stringify!($SelfT), ").wrapping_sub_unsigned(", stringify!($UnsignedT), "::MAX), -1);")]
         /// ```
-        #[unstable(feature = "mixed_integer_ops", issue = "87840")]
-        #[rustc_const_unstable(feature = "mixed_integer_ops", issue = "87840")]
+        #[stable(feature = "mixed_integer_ops", since = "CURRENT_RUSTC_VERSION")]
+        #[rustc_const_stable(feature = "mixed_integer_ops", since = "CURRENT_RUSTC_VERSION")]
         #[must_use = "this returns the result of the operation, \
                       without modifying the original"]
         #[inline(always)]
@@ -1574,13 +1568,12 @@ macro_rules! int_impl {
         /// Basic usage:
         ///
         /// ```
-        /// # #![feature(mixed_integer_ops)]
         #[doc = concat!("assert_eq!(1", stringify!($SelfT), ".overflowing_add_unsigned(2), (3, false));")]
         #[doc = concat!("assert_eq!((", stringify!($SelfT), "::MIN).overflowing_add_unsigned(", stringify!($UnsignedT), "::MAX), (", stringify!($SelfT), "::MAX, false));")]
         #[doc = concat!("assert_eq!((", stringify!($SelfT), "::MAX - 2).overflowing_add_unsigned(3), (", stringify!($SelfT), "::MIN, true));")]
         /// ```
-        #[unstable(feature = "mixed_integer_ops", issue = "87840")]
-        #[rustc_const_unstable(feature = "mixed_integer_ops", issue = "87840")]
+        #[stable(feature = "mixed_integer_ops", since = "CURRENT_RUSTC_VERSION")]
+        #[rustc_const_stable(feature = "mixed_integer_ops", since = "CURRENT_RUSTC_VERSION")]
         #[must_use = "this returns the result of the operation, \
                       without modifying the original"]
         #[inline]
@@ -1658,13 +1651,12 @@ macro_rules! int_impl {
         /// Basic usage:
         ///
         /// ```
-        /// # #![feature(mixed_integer_ops)]
         #[doc = concat!("assert_eq!(1", stringify!($SelfT), ".overflowing_sub_unsigned(2), (-1, false));")]
         #[doc = concat!("assert_eq!((", stringify!($SelfT), "::MAX).overflowing_sub_unsigned(", stringify!($UnsignedT), "::MAX), (", stringify!($SelfT), "::MIN, false));")]
         #[doc = concat!("assert_eq!((", stringify!($SelfT), "::MIN + 2).overflowing_sub_unsigned(3), (", stringify!($SelfT), "::MAX, true));")]
         /// ```
-        #[unstable(feature = "mixed_integer_ops", issue = "87840")]
-        #[rustc_const_unstable(feature = "mixed_integer_ops", issue = "87840")]
+        #[stable(feature = "mixed_integer_ops", since = "CURRENT_RUSTC_VERSION")]
+        #[rustc_const_stable(feature = "mixed_integer_ops", since = "CURRENT_RUSTC_VERSION")]
         #[must_use = "this returns the result of the operation, \
                       without modifying the original"]
         #[inline]
diff --git a/library/core/src/num/uint_macros.rs b/library/core/src/num/uint_macros.rs
index 46fd7f2d0e493..46b0ca2303406 100644
--- a/library/core/src/num/uint_macros.rs
+++ b/library/core/src/num/uint_macros.rs
@@ -474,13 +474,12 @@ macro_rules! uint_impl {
         /// Basic usage:
         ///
         /// ```
-        /// # #![feature(mixed_integer_ops)]
         #[doc = concat!("assert_eq!(1", stringify!($SelfT), ".checked_add_signed(2), Some(3));")]
         #[doc = concat!("assert_eq!(1", stringify!($SelfT), ".checked_add_signed(-2), None);")]
         #[doc = concat!("assert_eq!((", stringify!($SelfT), "::MAX - 2).checked_add_signed(3), None);")]
         /// ```
-        #[unstable(feature = "mixed_integer_ops", issue = "87840")]
-        #[rustc_const_unstable(feature = "mixed_integer_ops", issue = "87840")]
+        #[stable(feature = "mixed_integer_ops", since = "CURRENT_RUSTC_VERSION")]
+        #[rustc_const_stable(feature = "mixed_integer_ops", since = "CURRENT_RUSTC_VERSION")]
         #[must_use = "this returns the result of the operation, \
                       without modifying the original"]
         #[inline]
@@ -1057,13 +1056,12 @@ macro_rules! uint_impl {
         /// Basic usage:
         ///
         /// ```
-        /// # #![feature(mixed_integer_ops)]
         #[doc = concat!("assert_eq!(1", stringify!($SelfT), ".saturating_add_signed(2), 3);")]
         #[doc = concat!("assert_eq!(1", stringify!($SelfT), ".saturating_add_signed(-2), 0);")]
         #[doc = concat!("assert_eq!((", stringify!($SelfT), "::MAX - 2).saturating_add_signed(4), ", stringify!($SelfT), "::MAX);")]
         /// ```
-        #[unstable(feature = "mixed_integer_ops", issue = "87840")]
-        #[rustc_const_unstable(feature = "mixed_integer_ops", issue = "87840")]
+        #[stable(feature = "mixed_integer_ops", since = "CURRENT_RUSTC_VERSION")]
+        #[rustc_const_stable(feature = "mixed_integer_ops", since = "CURRENT_RUSTC_VERSION")]
         #[must_use = "this returns the result of the operation, \
                       without modifying the original"]
         #[inline]
@@ -1198,13 +1196,12 @@ macro_rules! uint_impl {
         /// Basic usage:
         ///
         /// ```
-        /// # #![feature(mixed_integer_ops)]
         #[doc = concat!("assert_eq!(1", stringify!($SelfT), ".wrapping_add_signed(2), 3);")]
         #[doc = concat!("assert_eq!(1", stringify!($SelfT), ".wrapping_add_signed(-2), ", stringify!($SelfT), "::MAX);")]
         #[doc = concat!("assert_eq!((", stringify!($SelfT), "::MAX - 2).wrapping_add_signed(4), 1);")]
         /// ```
-        #[unstable(feature = "mixed_integer_ops", issue = "87840")]
-        #[rustc_const_unstable(feature = "mixed_integer_ops", issue = "87840")]
+        #[stable(feature = "mixed_integer_ops", since = "CURRENT_RUSTC_VERSION")]
+        #[rustc_const_stable(feature = "mixed_integer_ops", since = "CURRENT_RUSTC_VERSION")]
         #[must_use = "this returns the result of the operation, \
                       without modifying the original"]
         #[inline]
@@ -1564,13 +1561,12 @@ macro_rules! uint_impl {
         /// Basic usage:
         ///
         /// ```
-        /// # #![feature(mixed_integer_ops)]
         #[doc = concat!("assert_eq!(1", stringify!($SelfT), ".overflowing_add_signed(2), (3, false));")]
         #[doc = concat!("assert_eq!(1", stringify!($SelfT), ".overflowing_add_signed(-2), (", stringify!($SelfT), "::MAX, true));")]
         #[doc = concat!("assert_eq!((", stringify!($SelfT), "::MAX - 2).overflowing_add_signed(4), (1, true));")]
         /// ```
-        #[unstable(feature = "mixed_integer_ops", issue = "87840")]
-        #[rustc_const_unstable(feature = "mixed_integer_ops", issue = "87840")]
+        #[stable(feature = "mixed_integer_ops", since = "CURRENT_RUSTC_VERSION")]
+        #[rustc_const_stable(feature = "mixed_integer_ops", since = "CURRENT_RUSTC_VERSION")]
         #[must_use = "this returns the result of the operation, \
                       without modifying the original"]
         #[inline]
diff --git a/library/std/src/lib.rs b/library/std/src/lib.rs
index c2b7a4d8648d0..ac5d0384d43dc 100644
--- a/library/std/src/lib.rs
+++ b/library/std/src/lib.rs
@@ -294,7 +294,6 @@
 #![feature(is_some_with)]
 #![feature(maybe_uninit_slice)]
 #![feature(maybe_uninit_write_slice)]
-#![feature(mixed_integer_ops)]
 #![feature(nonnull_slice_from_raw_parts)]
 #![feature(panic_can_unwind)]
 #![feature(panic_info_message)]