bump Rust, add patch for missing error_in_core feature

rust-src.diff

@@ -0,0 +1,84 @@
+diff --git a/library/core/src/error.rs b/library/core/src/error.rs
+index c32a54b77ef..1170221c10c 100644
+--- a/library/core/src/error.rs
++++ b/library/core/src/error.rs
+@@ -130,6 +130,7 @@ fn cause(&self) -> Option<&dyn Error> {
+     ///
+     /// ```rust
+     /// #![feature(error_generic_member_access)]
++    /// #![feature(error_in_core)]
+     /// use core::fmt;
+     /// use core::error::{request_ref, Request};
+     ///
+@@ -360,6 +361,7 @@ pub fn sources(&self) -> Source<'_> {
+ ///
+ /// ```rust
+ /// # #![feature(error_generic_member_access)]
++/// # #![feature(error_in_core)]
+ /// use std::error::Error;
+ /// use core::error::request_value;
+ ///
+@@ -383,6 +385,7 @@ pub fn request_value<'a, T>(err: &'a (impl Error + ?Sized)) -> Option<T>
+ ///
+ /// ```rust
+ /// # #![feature(error_generic_member_access)]
++/// # #![feature(error_in_core)]
+ /// use core::error::Error;
+ /// use core::error::request_ref;
+ ///
+@@ -454,6 +457,7 @@ fn request_by_type_tag<'a, I>(err: &'a (impl Error + ?Sized)) -> Option<I::Reifi
+ ///
+ /// ```
+ /// #![feature(error_generic_member_access)]
++/// #![feature(error_in_core)]
+ /// use core::fmt;
+ /// use core::error::Request;
+ /// use core::error::request_ref;
+@@ -524,6 +528,7 @@ fn new<'b>(erased: &'b mut (dyn Erased<'a> + 'a)) -> &'b mut Request<'a> {
+     ///
+     /// ```rust
+     /// #![feature(error_generic_member_access)]
++    /// #![feature(error_in_core)]
+     ///
+     /// use core::error::Request;
+     ///
+@@ -558,6 +563,7 @@ pub fn provide_value<T>(&mut self, value: T) -> &mut Self
+     ///
+     /// ```rust
+     /// #![feature(error_generic_member_access)]
++    /// #![feature(error_in_core)]
+     ///
+     /// use core::error::Request;
+     ///
+@@ -593,6 +599,7 @@ pub fn provide_value_with<T>(&mut self, fulfil: impl FnOnce() -> T) -> &mut Self
+     ///
+     /// ```rust
+     /// #![feature(error_generic_member_access)]
++    /// #![feature(error_in_core)]
+     ///
+     /// use core::error::Request;
+     ///
+@@ -625,6 +632,7 @@ pub fn provide_ref<T: ?Sized + 'static>(&mut self, value: &'a T) -> &mut Self {
+     ///
+     /// ```rust
+     /// #![feature(error_generic_member_access)]
++    /// #![feature(error_in_core)]
+     ///
+     /// use core::error::Request;
+     ///
+@@ -691,6 +699,7 @@ fn provide_with<I>(&mut self, fulfil: impl FnOnce() -> I::Reified) -> &mut Self
+     ///
+     /// ```rust
+     /// #![feature(error_generic_member_access)]
++    /// #![feature(error_in_core)]
+     ///
+     /// use core::error::Request;
+     /// use core::error::request_value;
+@@ -778,6 +787,7 @@ pub fn would_be_satisfied_by_value_of<T>(&self) -> bool
+     ///
+     /// ```rust
+     /// #![feature(error_generic_member_access)]
++    /// #![feature(error_in_core)]
+     ///
+     /// use core::error::Request;
+     /// use core::error::request_ref;

rust-version

@@ -1 +1 @@
-nightly-2023-08-05
+nightly-2023-08-15