rust-lang · carols10cents · Jun 29, 2026 · Jun 29, 2026
diff --git a/.github/workflows/main.yml b/.github/workflows/main.yml
@@ -15,8 +15,8 @@ jobs:
     - name: Install Rust
       run: |
         rustup set profile minimal
-        rustup toolchain install 1.94 -c rust-docs
-        rustup default 1.94
+        rustup toolchain install 1.95 -c rust-docs
+        rustup default 1.95
     - name: Install mdbook
       run: |
         mkdir bin
@@ -50,8 +50,8 @@ jobs:
     - name: Install Rust
       run: |
         rustup set profile minimal
-        rustup toolchain install 1.94 -c rust-docs
-        rustup default 1.94
+        rustup toolchain install 1.95 -c rust-docs
+        rustup default 1.95
     - name: Run `tools` package tests
       run: |
         cargo test

diff --git a/listings/ch02-guessing-game-tutorial/listing-02-04/output.txt b/listings/ch02-guessing-game-tutorial/listing-02-04/output.txt
@@ -8,20 +8,17 @@ $ cargo build
    Compiling rand v0.8.5
    Compiling guessing_game v0.1.0 (file:///projects/guessing_game)
 error[E0308]: mismatched types
-   --> src/main.rs:23:21
-    |
- 23 |     match guess.cmp(&secret_number) {
-    |                 --- ^^^^^^^^^^^^^^ expected `&String`, found `&{integer}`
-    |                 |
-    |                 arguments to this method are incorrect
-    |
-    = note: expected reference `&String`
-               found reference `&{integer}`
+  --> src/main.rs:23:21
+   |
+23 |     match guess.cmp(&secret_number) {
+   |                 --- ^^^^^^^^^^^^^^ expected `&String`, found `&{integer}`
+   |                 |
+   |                 arguments to this method are incorrect
+   |
+   = note: expected reference `&String`
+              found reference `&{integer}`
 note: method defined here
-   --> file:///home/.rustup/toolchains/1.94/lib/rustlib/src/rust/library/core/src/cmp.rs:991:8
-    |
-991 |     fn cmp(&self, other: &Self) -> Ordering;
-    |        ^^^
+  --> /rustc/59807616e1fa2540724bfbac14d7976d7e4a3860/library/core/src/cmp.rs:999:7
 
 For more information about this error, try `rustc --explain E0308`.
 error: could not compile `guessing_game` (bin "guessing_game") due to 1 previous error
diff --git a/listings/ch04-understanding-ownership/no-listing-04-cant-use-after-move/output.txt b/listings/ch04-understanding-ownership/no-listing-04-cant-use-after-move/output.txt
@@ -11,7 +11,6 @@ error[E0382]: borrow of moved value: `s1`
 5 |     println!("{s1}, world!");
   |                ^^ value borrowed here after move
   |
-  = note: this error originates in the macro `$crate::format_args_nl` which comes from the expansion of the macro `println` (in Nightly builds, run with -Z macro-backtrace for more info)
 help: consider cloning the value if the performance cost is acceptable
   |
 3 |     let s2 = s1.clone();

diff --git a/listings/ch05-using-structs-to-structure-related-data/listing-05-11/output.txt b/listings/ch05-using-structs-to-structure-related-data/listing-05-11/output.txt
@@ -12,7 +12,6 @@ help: the trait `std::fmt::Display` is not implemented for `Rectangle`
  1 | struct Rectangle {
    | ^^^^^^^^^^^^^^^^
    = note: in format strings you may be able to use `{:?}` (or {:#?} for pretty-print) instead
-   = note: this error originates in the macro `$crate::format_args_nl` which comes from the expansion of the macro `println` (in Nightly builds, run with -Z macro-backtrace for more info)
 
 For more information about this error, try `rustc --explain E0277`.
 error: could not compile `rectangles` (bin "rectangles") due to 1 previous error
diff --git a/listings/ch05-using-structs-to-structure-related-data/output-only-01-debug/output.txt b/listings/ch05-using-structs-to-structure-related-data/output-only-01-debug/output.txt
@@ -10,7 +10,6 @@ error[E0277]: `Rectangle` doesn't implement `Debug`
    |
    = help: the trait `Debug` is not implemented for `Rectangle`
    = note: add `#[derive(Debug)]` to `Rectangle` or manually `impl Debug for Rectangle`
-   = note: this error originates in the macro `$crate::format_args_nl` which comes from the expansion of the macro `println` (in Nightly builds, run with -Z macro-backtrace for more info)
 help: consider annotating `Rectangle` with `#[derive(Debug)]`
    |
  1 + #[derive(Debug)]

diff --git a/listings/ch06-enums-and-pattern-matching/no-listing-07-cant-use-option-directly/output.txt b/listings/ch06-enums-and-pattern-matching/no-listing-07-cant-use-option-directly/output.txt
@@ -1,32 +1,29 @@
 $ cargo run
    Compiling enums v0.1.0 (file:///projects/enums)
 error[E0277]: cannot add `Option<i8>` to `i8`
-   --> src/main.rs:5:17
-    |
-  5 |     let sum = x + y;
-    |                 ^ no implementation for `i8 + Option<i8>`
-    |
-    = help: the trait `Add<Option<i8>>` is not implemented for `i8`
+ --> src/main.rs:5:17
+  |
+5 |     let sum = x + y;
+  |                 ^ no implementation for `i8 + Option<i8>`
+  |
+  = help: the trait `Add<Option<i8>>` is not implemented for `i8`
 help: the following other types implement trait `Add<Rhs>`
-   --> file:///home/.rustup/toolchains/1.94/lib/rustlib/src/rust/library/core/src/ops/arith.rs:99:9
-    |
- 99 |         impl const Add for $t {
-    |         ^^^^^^^^^^^^^^^^^^^^^ `i8` implements `Add`
-...
-114 | add_impl! { usize u8 u16 u32 u64 u128 isize i8 i16 i32 i64 i128 f16 f32 f64 f128 }
-    | ---------------------------------------------------------------------------------- in this macro invocation
-    |
-   ::: /Users/carolnichols/.rustup/toolchains/1.94-aarch64-apple-darwin/lib/rustlib/src/rust/library/core/src/internal_macros.rs:22:9
-    |
- 22 |         impl const $imp<$u> for &$t {
-    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^ `&i8` implements `Add<i8>`
-...
- 33 |         impl const $imp<&$u> for $t {
-    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^ `i8` implements `Add<&i8>`
-...
- 44 |         impl const $imp<&$u> for &$t {
-    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ `&i8` implements `Add`
-    = note: this error originates in the macro `add_impl` (in Nightly builds, run with -Z macro-backtrace for more info)
+ --> /rustc/59807616e1fa2540724bfbac14d7976d7e4a3860/library/core/src/ops/arith.rs:99:8
+  |
+  = note: `i8` implements `Add`
+ ::: /rustc/59807616e1fa2540724bfbac14d7976d7e4a3860/library/core/src/ops/arith.rs:114:0
+  |
+  = note: in this macro invocation
+ --> /rustc/59807616e1fa2540724bfbac14d7976d7e4a3860/library/core/src/internal_macros.rs:22:8
+  |
+  = note: `&i8` implements `Add<i8>`
+ ::: /rustc/59807616e1fa2540724bfbac14d7976d7e4a3860/library/core/src/internal_macros.rs:33:8
+  |
+  = note: `i8` implements `Add<&i8>`
+ ::: /rustc/59807616e1fa2540724bfbac14d7976d7e4a3860/library/core/src/internal_macros.rs:44:8
+  |
+  = note: `&i8` implements `Add`
+  = note: this error originates in the macro `add_impl` (in Nightly builds, run with -Z macro-backtrace for more info)
 
 For more information about this error, try `rustc --explain E0277`.
 error: could not compile `enums` (bin "enums") due to 1 previous error
diff --git a/listings/ch06-enums-and-pattern-matching/no-listing-10-non-exhaustive-match/output.txt b/listings/ch06-enums-and-pattern-matching/no-listing-10-non-exhaustive-match/output.txt
@@ -1,25 +1,22 @@
 $ cargo run
    Compiling enums v0.1.0 (file:///projects/enums)
 error[E0004]: non-exhaustive patterns: `None` not covered
-   --> src/main.rs:3:15
-    |
-  3 |         match x {
-    |               ^ pattern `None` not covered
-    |
+ --> src/main.rs:3:15
+  |
+3 |         match x {
+  |               ^ pattern `None` not covered
+  |
 note: `Option<i32>` defined here
-   --> file:///home/.rustup/toolchains/1.94/lib/rustlib/src/rust/library/core/src/option.rs:600:1
-    |
-600 | pub enum Option<T> {
-    | ^^^^^^^^^^^^^^^^^^
-...
-604 |     None,
-    |     ---- not covered
-    = note: the matched value is of type `Option<i32>`
+ --> /rustc/59807616e1fa2540724bfbac14d7976d7e4a3860/library/core/src/option.rs:600:0
+ ::: /rustc/59807616e1fa2540724bfbac14d7976d7e4a3860/library/core/src/option.rs:604:4
+  |
+  = note: not covered
+  = note: the matched value is of type `Option<i32>`
 help: ensure that all possible cases are being handled by adding a match arm with a wildcard pattern or an explicit pattern as shown
-    |
-  4 ~             Some(i) => Some(i + 1),
-  5 ~             None => todo!(),
-    |
+  |
+4 ~             Some(i) => Some(i + 1),
+5 ~             None => todo!(),
+  |
 
 For more information about this error, try `rustc --explain E0004`.
 error: could not compile `enums` (bin "enums") due to 1 previous error
diff --git a/listings/ch07-managing-growing-projects/listing-07-12/output.txt b/listings/ch07-managing-growing-projects/listing-07-12/output.txt
@@ -1,6 +1,6 @@
 $ cargo build
    Compiling restaurant v0.1.0 (file:///projects/restaurant)
-error[E0433]: failed to resolve: use of unresolved module or unlinked crate `hosting`
+error[E0433]: cannot find module or crate `hosting` in this scope
   --> src/lib.rs:11:9
    |
 11 |         hosting::add_to_waitlist();

diff --git a/listings/ch08-common-collections/listing-08-19/output.txt b/listings/ch08-common-collections/listing-08-19/output.txt
@@ -1,25 +1,22 @@
 $ cargo run
    Compiling collections v0.1.0 (file:///projects/collections)
 error[E0277]: the type `str` cannot be indexed by `{integer}`
-   --> src/main.rs:3:16
-    |
-  3 |     let h = s1[0];
-    |                ^ string indices are ranges of `usize`
-    |
-    = help: the trait `SliceIndex<str>` is not implemented for `{integer}`
-    = note: you can use `.chars().nth()` or `.bytes().nth()`
-            for more information, see chapter 8 in The Book: <https://doc.rust-lang.org/book/ch08-02-strings.html#indexing-into-strings>
+ --> src/main.rs:3:16
+  |
+3 |     let h = s1[0];
+  |                ^ string indices are ranges of `usize`
+  |
+  = help: the trait `SliceIndex<str>` is not implemented for `{integer}`
+  = note: you can use `.chars().nth()` or `.bytes().nth()`
+          for more information, see chapter 8 in The Book: <https://doc.rust-lang.org/book/ch08-02-strings.html#indexing-into-strings>
 help: the following other types implement trait `SliceIndex<T>`
-   --> file:///home/.rustup/toolchains/1.94/lib/rustlib/src/rust/library/core/src/slice/index.rs:214:1
-    |
-214 | unsafe impl<T> const SliceIndex<[T]> for usize {
-    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ `usize` implements `SliceIndex<[T]>`
-    |
-   ::: /Users/carolnichols/.rustup/toolchains/1.94-aarch64-apple-darwin/lib/rustlib/src/rust/library/core/src/bstr/traits.rs:203:1
-    |
-203 | unsafe impl SliceIndex<ByteStr> for usize {
-    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ `usize` implements `SliceIndex<ByteStr>`
-    = note: required for `String` to implement `Index<{integer}>`
+ --> /rustc/59807616e1fa2540724bfbac14d7976d7e4a3860/library/core/src/slice/index.rs:214:0
+  |
+  = note: `usize` implements `SliceIndex<[T]>`
+ --> /rustc/59807616e1fa2540724bfbac14d7976d7e4a3860/library/core/src/bstr/traits.rs:197:0
+  |
+  = note: `usize` implements `SliceIndex<ByteStr>`
+  = note: required for `String` to implement `Index<{integer}>`
 
 For more information about this error, try `rustc --explain E0277`.
 error: could not compile `collections` (bin "collections") due to 1 previous error
diff --git a/listings/ch08-common-collections/output-only-01-not-char-boundary/output.txt b/listings/ch08-common-collections/output-only-01-not-char-boundary/output.txt
@@ -4,5 +4,5 @@ $ cargo run
      Running `target/debug/collections`
 
 thread 'main' (6017738) panicked at src/main.rs:4:19:
-byte index 1 is not a char boundary; it is inside 'З' (bytes 0..2) of `Здравствуйте`
+end byte index 1 is not a char boundary; it is inside 'З' (bytes 0..2) of `Здравствуйте`
 note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace
diff --git a/listings/ch13-functional-features/listing-13-08/output.txt b/listings/ch13-functional-features/listing-13-08/output.txt
@@ -1,27 +1,24 @@
 $ cargo run
    Compiling rectangles v0.1.0 (file:///projects/rectangles)
 error[E0507]: cannot move out of `value`, a captured variable in an `FnMut` closure
-   --> src/main.rs:18:30
-    |
- 15 |     let value = String::from("closure called");
-    |         -----   ------------------------------ move occurs because `value` has type `String`, which does not implement the `Copy` trait
-    |         |
-    |         captured outer variable
- 16 |
- 17 |     list.sort_by_key(|r| {
-    |                      --- captured by this `FnMut` closure
- 18 |         sort_operations.push(value);
-    |                              ^^^^^ `value` is moved here
-    |
+  --> src/main.rs:18:30
+   |
+15 |     let value = String::from("closure called");
+   |         -----   ------------------------------ move occurs because `value` has type `String`, which does not implement the `Copy` trait
+   |         |
+   |         captured outer variable
+16 |
+17 |     list.sort_by_key(|r| {
+   |                      --- captured by this `FnMut` closure
+18 |         sort_operations.push(value);
+   |                              ^^^^^ `value` is moved here
+   |
 help: `Fn` and `FnMut` closures require captured values to be able to be consumed multiple times, but `FnOnce` closures may consume them only once
-   --> file:///home/.rustup/toolchains/1.94/lib/rustlib/src/rust/library/alloc/src/slice.rs:249:12
-    |
-249 |         F: FnMut(&T) -> K,
-    |            ^^^^^^^^^^^^^^
+  --> /rustc/59807616e1fa2540724bfbac14d7976d7e4a3860/library/alloc/src/slice.rs:249:11
 help: consider cloning the value if the performance cost is acceptable
-    |
- 18 |         sort_operations.push(value.clone());
-    |                                   ++++++++
+   |
+18 |         sort_operations.push(value.clone());
+   |                                   ++++++++
 
 For more information about this error, try `rustc --explain E0507`.
 error: could not compile `rectangles` (bin "rectangles") due to 1 previous error
diff --git a/listings/ch15-smart-pointers/output-only-01-comparing-to-reference/output.txt b/listings/ch15-smart-pointers/output-only-01-comparing-to-reference/output.txt
@@ -1,18 +1,12 @@
 $ cargo run
    Compiling deref-example v0.1.0 (file:///projects/deref-example)
 error[E0277]: can't compare `{integer}` with `&{integer}`
-  --> src/main.rs:6:5
-   |
- 6 |     assert_eq!(5, y);
-   |     ^^^^^^^^^^^^^^^^ no implementation for `{integer} == &{integer}`
-   |
-   = help: the trait `PartialEq<&{integer}>` is not implemented for `{integer}`
-   = note: this error originates in the macro `assert_eq` (in Nightly builds, run with -Z macro-backtrace for more info)
-help: consider dereferencing here
-  --> file:///home/.rustup/toolchains/1.94/lib/rustlib/src/rust/library/core/src/macros/mod.rs:46:35
-   |
-46 |                 if !(*left_val == **right_val) {
-   |                                   +
+ --> src/main.rs:6:5
+  |
+6 |     assert_eq!(5, y);
+  |     ^^^^^^^^^^^^^^^^ no implementation for `{integer} == &{integer}`
+  |
+  = help: the trait `PartialEq<&{integer}>` is not implemented for `{integer}`
 
 For more information about this error, try `rustc --explain E0277`.
 error: could not compile `deref-example` (bin "deref-example") due to 1 previous error
diff --git a/listings/ch16-fearless-concurrency/listing-16-09/output.txt b/listings/ch16-fearless-concurrency/listing-16-09/output.txt
@@ -9,8 +9,6 @@ error[E0382]: borrow of moved value: `val`
    |                 --- value moved here
 10 |         println!("val is {val}");
    |                           ^^^ value borrowed here after move
-   |
-   = note: this error originates in the macro `$crate::format_args_nl` which comes from the expansion of the macro `println` (in Nightly builds, run with -Z macro-backtrace for more info)
 
 For more information about this error, try `rustc --explain E0382`.
 error: could not compile `message-passing` (bin "message-passing") due to 1 previous error
diff --git a/listings/ch16-fearless-concurrency/listing-16-14/output.txt b/listings/ch16-fearless-concurrency/listing-16-14/output.txt
@@ -1,34 +1,28 @@
 $ cargo run
    Compiling shared-state v0.1.0 (file:///projects/shared-state)
 error[E0277]: `Rc<std::sync::Mutex<i32>>` cannot be sent between threads safely
-   --> src/main.rs:11:36
-    |
- 11 |           let handle = thread::spawn(move || {
-    |                        ------------- ^------
-    |                        |             |
-    |  ______________________|_____________within this `{closure@src/main.rs:11:36: 11:43}`
-    | |                      |
-    | |                      required by a bound introduced by this call
- 12 | |             let mut num = counter.lock().unwrap();
- 13 | |
- 14 | |             *num += 1;
- 15 | |         });
-    | |_________^ `Rc<std::sync::Mutex<i32>>` cannot be sent between threads safely
-    |
-    = help: within `{closure@src/main.rs:11:36: 11:43}`, the trait `Send` is not implemented for `Rc<std::sync::Mutex<i32>>`
+  --> src/main.rs:11:36
+   |
+11 |           let handle = thread::spawn(move || {
+   |                        ------------- ^------
+   |                        |             |
+   |  ______________________|_____________within this `{closure@src/main.rs:11:36: 11:43}`
+   | |                      |
+   | |                      required by a bound introduced by this call
+12 | |             let mut num = counter.lock().unwrap();
+13 | |
+14 | |             *num += 1;
+15 | |         });
+   | |_________^ `Rc<std::sync::Mutex<i32>>` cannot be sent between threads safely
+   |
+   = help: within `{closure@src/main.rs:11:36: 11:43}`, the trait `Send` is not implemented for `Rc<std::sync::Mutex<i32>>`
 note: required because it's used within this closure
-   --> src/main.rs:11:36
-    |
- 11 |         let handle = thread::spawn(move || {
-    |                                    ^^^^^^^
+  --> src/main.rs:11:36
+   |
+11 |         let handle = thread::spawn(move || {
+   |                                    ^^^^^^^
 note: required by a bound in `spawn`
-   --> file:///home/.rustup/toolchains/1.94/lib/rustlib/src/rust/library/std/src/thread/functions.rs:128:8
-    |
-125 | pub fn spawn<F, T>(f: F) -> JoinHandle<T>
-    |        ----- required by a bound in this function
-...
-128 |     F: Send + 'static,
-    |        ^^^^ required by this bound in `spawn`
+  --> /rustc/59807616e1fa2540724bfbac14d7976d7e4a3860/library/std/src/thread/functions.rs:125:0
 
 For more information about this error, try `rustc --explain E0277`.
 error: could not compile `shared-state` (bin "shared-state") due to 1 previous error
diff --git a/listings/ch20-advanced-features/listing-20-07/output.txt b/listings/ch20-advanced-features/listing-20-07/output.txt
@@ -1,6 +1,6 @@
 $ cargo +nightly miri run
    Compiling unsafe-example v0.1.0 (file:///projects/unsafe-example)
-    Finished `dev` profile [unoptimized + debuginfo] target(s) in 0.01s
+    Finished `dev` profile [unoptimized + debuginfo] target(s) in 0.17s
      Running `file:///home/.rustup/toolchains/nightly/bin/cargo-miri runner target/miri/debug/unsafe-example`
 warning: integer-to-pointer cast
  --> src/main.rs:5:13
@@ -14,7 +14,7 @@ warning: integer-to-pointer cast
   = help: you can then set `MIRIFLAGS=-Zmiri-strict-provenance` to ensure you are not relying on `with_exposed_provenance` semantics
   = help: alternatively, `MIRIFLAGS=-Zmiri-permissive-provenance` disables this warning
 
-error: Undefined Behavior: pointer not dereferenceable: pointer must be dereferenceable for 40000 bytes, but got 0x1234[noalloc] which is a dangling pointer (it has no provenance)
+error: Undefined Behavior: constructing invalid value of type &mut [i32]: encountered a dangling reference (0x1234[noalloc] has no provenance)
  --> src/main.rs:7:35
   |
 7 |     let values: &[i32] = unsafe { slice::from_raw_parts_mut(r, 10000) };

diff --git a/listings/ch21-web-server/listing-21-12/output.txt b/listings/ch21-web-server/listing-21-12/output.txt
@@ -1,6 +1,6 @@
 $ cargo check
     Checking hello v0.1.0 (file:///projects/hello)
-error[E0433]: failed to resolve: use of undeclared type `ThreadPool`
+error[E0433]: cannot find type `ThreadPool` in this scope
   --> src/main.rs:11:16
    |
 11 |     let pool = ThreadPool::new(4);