Auto merge of #105918 - matthiaskrgr:rollup-mmazd62, r=matthiaskrgr

Rollup of 7 pull requests

Successful merges:

 - #105801 (Realistic `Path::as_mut_os_str` doctest)
 - #105860 (Add long error docs for `E0460` and `E0457`)
 - #105895 (Test that we don't add a new kind of breaking change with TAITs)
 - #105902 (docs: improve pin docs)
 - #105910 (Update books)
 - #105913 (rustdoc: remove width-limiter from source pages, stop overriding CSS)
 - #105915 (Revert "Replace usage of `ResumeTy` in async lowering with `Context`")

Failed merges:

r? `@ghost`
`@rustbot` modify labels: rollup

26 files changed, 73 insertions, 29 deletions

diff --git a/src/doc/nomicon b/src/doc/nomicon
-Subproject ae406aa5287a9e025abb72343aaceec98458c11
+Subproject dd37e21ccee43918ed18a71581bb2af537ffe4f
diff --git a/src/doc/rust-by-example b/src/doc/rust-by-example
-Subproject a9869b4a3c4cac3bc6099b41f088679e268400b
+Subproject 995df09b65c582eb6290ab7ea5d9485983eb4c3
diff --git a/src/doc/rustc-dev-guide b/src/doc/rustc-dev-guide
-Subproject e269950a57fa6fcda356426545fb5aa3691a7ce
+Subproject 8b42eb5f57d3d8ed2257a22d0e850d9db52afed
diff --git a/src/librustdoc/html/static/css/rustdoc.css b/src/librustdoc/html/static/css/rustdoc.css
index 022ed606cc3..efb19467c87 100644
--- a/src/librustdoc/html/static/css/rustdoc.css
+++ b/src/librustdoc/html/static/css/rustdoc.css
@@ -322,10 +322,6 @@ main {
 	margin-right: auto;
 }
 
-.source .width-limiter {
-	max-width: unset;
-}
-
 details:not(.rustdoc-toggle) summary {
 	margin-bottom: .6em;
 }
diff --git a/src/librustdoc/html/templates/page.html b/src/librustdoc/html/templates/page.html
index aa3bf827db4..bcaff957af2 100644
--- a/src/librustdoc/html/templates/page.html
+++ b/src/librustdoc/html/templates/page.html
@@ -99,7 +99,7 @@
         {{- sidebar|safe -}}
     </nav> {#- -#}
     <main> {#- -#}
-        <div class="width-limiter"> {#- -#}
+        {%- if page.css_class != "source" -%}<div class="width-limiter">{%- endif -%}
             <nav class="sub"> {#- -#}
                 {%- if page.css_class == "source" -%}
                 <a class="sub-logo-container" href="{{page.root_path|safe}}{{krate_with_trailing_slash|safe}}index.html"> {#- -#}
@@ -132,7 +132,7 @@
                 </form> {#- -#}
             </nav> {#- -#}
             <section id="main-content" class="content">{{- content|safe -}}</section> {#- -#}
-        </div> {#- -#}
+        {%- if page.css_class != "source" -%}</div>{%- endif -%}
     </main> {#- -#}
     {{- layout.external_html.after_content|safe -}}
     <div id="rustdoc-vars" {# -#}
diff --git a/src/test/ui-fulldeps/macro-crate-rlib.stderr b/src/test/ui-fulldeps/macro-crate-rlib.stderr
index 7b31f28a26e..9c2b992b765 100644
--- a/src/test/ui-fulldeps/macro-crate-rlib.stderr
+++ b/src/test/ui-fulldeps/macro-crate-rlib.stderr
@@ -6,3 +6,4 @@ LL | #![plugin(rlib_crate_test)]
 
 error: aborting due to previous error
 
+For more information about this error, try `rustc --explain E0457`.
diff --git a/src/test/ui/async-await/async-await-let-else.drop-tracking.stderr b/src/test/ui/async-await/async-await-let-else.drop-tracking.stderr
index f0f5245a3b4..fb83ca90a37 100644
--- a/src/test/ui/async-await/async-await-let-else.drop-tracking.stderr
+++ b/src/test/ui/async-await/async-await-let-else.drop-tracking.stderr
@@ -40,7 +40,7 @@ LL |   async fn bar2<T>(_: T) -> ! {
 LL | |     panic!()
 LL | | }
    | |_^
-   = note: required because it captures the following types: `&mut Context<'_>`, `Option<bool>`, `impl Future<Output = !>`, `()`
+   = note: required because it captures the following types: `ResumeTy`, `Option<bool>`, `impl Future<Output = !>`, `()`
 note: required because it's used within this `async fn` body
   --> $DIR/async-await-let-else.rs:21:32
    |
diff --git a/src/test/ui/async-await/issue-68112.drop_tracking.stderr b/src/test/ui/async-await/issue-68112.drop_tracking.stderr
index 1c90bedae79..f2802698fd5 100644
--- a/src/test/ui/async-await/issue-68112.drop_tracking.stderr
+++ b/src/test/ui/async-await/issue-68112.drop_tracking.stderr
@@ -57,7 +57,7 @@ note: required because it appears within the type `impl Future<Output = Arc<RefC
    |
 LL | fn make_non_send_future2() -> impl Future<Output = Arc<RefCell<i32>>> {
    |                               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-   = note: required because it captures the following types: `&mut Context<'_>`, `impl Future<Output = Arc<RefCell<i32>>>`, `()`, `Ready<i32>`
+   = note: required because it captures the following types: `ResumeTy`, `impl Future<Output = Arc<RefCell<i32>>>`, `()`, `Ready<i32>`
 note: required because it's used within this `async` block
   --> $DIR/issue-68112.rs:60:20
    |
diff --git a/src/test/ui/async-await/issue-68112.no_drop_tracking.stderr b/src/test/ui/async-await/issue-68112.no_drop_tracking.stderr
index e09ae7fedd8..38eb85b302f 100644
--- a/src/test/ui/async-await/issue-68112.no_drop_tracking.stderr
+++ b/src/test/ui/async-await/issue-68112.no_drop_tracking.stderr
@@ -57,7 +57,7 @@ note: required because it appears within the type `impl Future<Output = Arc<RefC
    |
 LL | fn make_non_send_future2() -> impl Future<Output = Arc<RefCell<i32>>> {
    |                               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-   = note: required because it captures the following types: `&mut Context<'_>`, `impl Future<Output = Arc<RefCell<i32>>>`, `()`, `i32`, `Ready<i32>`
+   = note: required because it captures the following types: `ResumeTy`, `impl Future<Output = Arc<RefCell<i32>>>`, `()`, `i32`, `Ready<i32>`
 note: required because it's used within this `async` block
   --> $DIR/issue-68112.rs:60:20
    |
diff --git a/src/test/ui/async-await/issue-69446-fnmut-capture.stderr b/src/test/ui/async-await/issue-69446-fnmut-capture.stderr
index e6ad2f0d444..3d2b0402bc5 100644
--- a/src/test/ui/async-await/issue-69446-fnmut-capture.stderr
+++ b/src/test/ui/async-await/issue-69446-fnmut-capture.stderr
@@ -14,9 +14,6 @@ LL | |     });
    |
    = note: `FnMut` closures only have access to their captured variables while they are executing...
    = note: ...therefore, they cannot allow references to captured variables to escape
-   = note: requirement occurs because of a mutable reference to `Context<'_>`
-   = note: mutable references are invariant over their type parameter
-   = help: see <https://doc.rust-lang.org/nomicon/subtyping.html> for more information about variance
 
 error: aborting due to previous error
 
diff --git a/src/test/ui/async-await/issue-70935-complex-spans.drop_tracking.stderr b/src/test/ui/async-await/issue-70935-complex-spans.drop_tracking.stderr
index a8fd97cde8f..721234aa4a7 100644
--- a/src/test/ui/async-await/issue-70935-complex-spans.drop_tracking.stderr
+++ b/src/test/ui/async-await/issue-70935-complex-spans.drop_tracking.stderr
@@ -18,7 +18,7 @@ LL |   async fn baz<T>(_c: impl FnMut() -> T) where T: Future<Output=()> {
    |  ___________________________________________________________________^
 LL | | }
    | |_^
-   = note: required because it captures the following types: `&mut Context<'_>`, `impl Future<Output = ()>`, `()`
+   = note: required because it captures the following types: `ResumeTy`, `impl Future<Output = ()>`, `()`
 note: required because it's used within this `async` block
   --> $DIR/issue-70935-complex-spans.rs:16:5
    |
diff --git a/src/test/ui/async-await/partial-drop-partial-reinit.drop_tracking.stderr b/src/test/ui/async-await/partial-drop-partial-reinit.drop_tracking.stderr
index 25876d50840..17b4ef7bdc6 100644
--- a/src/test/ui/async-await/partial-drop-partial-reinit.drop_tracking.stderr
+++ b/src/test/ui/async-await/partial-drop-partial-reinit.drop_tracking.stderr
@@ -11,7 +11,7 @@ LL | async fn foo() {
    |
    = help: within `impl Future<Output = ()>`, the trait `Send` is not implemented for `NotSend`
    = note: required because it appears within the type `(NotSend,)`
-   = note: required because it captures the following types: `&mut Context<'_>`, `(NotSend,)`, `()`, `impl Future<Output = ()>`
+   = note: required because it captures the following types: `ResumeTy`, `(NotSend,)`, `()`, `impl Future<Output = ()>`
 note: required because it's used within this `async fn` body
   --> $DIR/partial-drop-partial-reinit.rs:31:16
    |
diff --git a/src/test/ui/async-await/partial-drop-partial-reinit.no_drop_tracking.stderr b/src/test/ui/async-await/partial-drop-partial-reinit.no_drop_tracking.stderr
index dba2a620779..34d8a159f10 100644
--- a/src/test/ui/async-await/partial-drop-partial-reinit.no_drop_tracking.stderr
+++ b/src/test/ui/async-await/partial-drop-partial-reinit.no_drop_tracking.stderr
@@ -11,7 +11,7 @@ LL | async fn foo() {
    |
    = help: within `impl Future<Output = ()>`, the trait `Send` is not implemented for `NotSend`
    = note: required because it appears within the type `(NotSend,)`
-   = note: required because it captures the following types: `&mut Context<'_>`, `(NotSend,)`, `impl Future<Output = ()>`, `()`
+   = note: required because it captures the following types: `ResumeTy`, `(NotSend,)`, `impl Future<Output = ()>`, `()`
 note: required because it's used within this `async fn` body
   --> $DIR/partial-drop-partial-reinit.rs:31:16
    |
diff --git a/src/test/ui/regions/closure-in-projection-issue-97405.rs b/src/test/ui/regions/closure-in-projection-issue-97405.rs
index 88b1c139651..e567d5c2723 100644
--- a/src/test/ui/regions/closure-in-projection-issue-97405.rs
+++ b/src/test/ui/regions/closure-in-projection-issue-97405.rs
@@ -22,11 +22,11 @@ fn good_generic_fn<T>() {
 // This should fail because `T` ends up in the upvars of the closure.
 fn bad_generic_fn<T: Copy>(t: T) {
     assert_static(opaque(async move { t; }).next());
-    //~^ ERROR the parameter type `T` may not live long enough
+    //~^ ERROR the associated type `<impl Iterator as Iterator>::Item` may not live long enough
     assert_static(opaque(move || { t; }).next());
     //~^ ERROR the associated type `<impl Iterator as Iterator>::Item` may not live long enough
     assert_static(opaque(opaque(async move { t; }).next()).next());
-    //~^ ERROR the parameter type `T` may not live long enough
+    //~^ ERROR the associated type `<impl Iterator as Iterator>::Item` may not live long enough
 }
 
 fn main() {}
diff --git a/src/test/ui/regions/closure-in-projection-issue-97405.stderr b/src/test/ui/regions/closure-in-projection-issue-97405.stderr
index 907964aaf37..c08f1059ebf 100644
--- a/src/test/ui/regions/closure-in-projection-issue-97405.stderr
+++ b/src/test/ui/regions/closure-in-projection-issue-97405.stderr
@@ -1,13 +1,11 @@
-error[E0310]: the parameter type `T` may not live long enough
+error[E0310]: the associated type `<impl Iterator as Iterator>::Item` may not live long enough
   --> $DIR/closure-in-projection-issue-97405.rs:24:5
    |
 LL |     assert_static(opaque(async move { t; }).next());
-   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ ...so that the type `T` will meet its required lifetime bounds
-   |
-help: consider adding an explicit lifetime bound...
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
-LL | fn bad_generic_fn<T: Copy + 'static>(t: T) {
-   |                           +++++++++
+   = help: consider adding an explicit lifetime bound `<impl Iterator as Iterator>::Item: 'static`...
+   = note: ...so that the type `<impl Iterator as Iterator>::Item` will meet its required lifetime bounds
 
 error[E0310]: the associated type `<impl Iterator as Iterator>::Item` may not live long enough
   --> $DIR/closure-in-projection-issue-97405.rs:26:5
@@ -18,16 +16,14 @@ LL |     assert_static(opaque(move || { t; }).next());
    = help: consider adding an explicit lifetime bound `<impl Iterator as Iterator>::Item: 'static`...
    = note: ...so that the type `<impl Iterator as Iterator>::Item` will meet its required lifetime bounds
 
-error[E0310]: the parameter type `T` may not live long enough
+error[E0310]: the associated type `<impl Iterator as Iterator>::Item` may not live long enough
   --> $DIR/closure-in-projection-issue-97405.rs:28:5
    |
 LL |     assert_static(opaque(opaque(async move { t; }).next()).next());
-   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ ...so that the type `T` will meet its required lifetime bounds
-   |
-help: consider adding an explicit lifetime bound...
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
-LL | fn bad_generic_fn<T: Copy + 'static>(t: T) {
-   |                           +++++++++
+   = help: consider adding an explicit lifetime bound `<impl Iterator as Iterator>::Item: 'static`...
+   = note: ...so that the type `<impl Iterator as Iterator>::Item` will meet its required lifetime bounds
 
 error: aborting due to 3 previous errors
 
diff --git a/src/test/ui/svh/changing-crates.stderr b/src/test/ui/svh/changing-crates.stderr
index 7244919e86d..caefdfc96f0 100644
--- a/src/test/ui/svh/changing-crates.stderr
+++ b/src/test/ui/svh/changing-crates.stderr
@@ -11,3 +11,4 @@ LL | extern crate b;
 
 error: aborting due to previous error
 
+For more information about this error, try `rustc --explain E0460`.
diff --git a/src/test/ui/svh/svh-change-lit.stderr b/src/test/ui/svh/svh-change-lit.stderr
index 1e97e9d0557..5e890c6aa57 100644
--- a/src/test/ui/svh/svh-change-lit.stderr
+++ b/src/test/ui/svh/svh-change-lit.stderr
@@ -11,3 +11,4 @@ LL | extern crate b;
 
 error: aborting due to previous error
 
+For more information about this error, try `rustc --explain E0460`.
diff --git a/src/test/ui/svh/svh-change-significant-cfg.stderr b/src/test/ui/svh/svh-change-significant-cfg.stderr
index f04046f4c87..dcc250d5216 100644
--- a/src/test/ui/svh/svh-change-significant-cfg.stderr
+++ b/src/test/ui/svh/svh-change-significant-cfg.stderr
@@ -11,3 +11,4 @@ LL | extern crate b;
 
 error: aborting due to previous error
 
+For more information about this error, try `rustc --explain E0460`.
diff --git a/src/test/ui/svh/svh-change-trait-bound.stderr b/src/test/ui/svh/svh-change-trait-bound.stderr
index a778c61806a..2035993d218 100644
--- a/src/test/ui/svh/svh-change-trait-bound.stderr
+++ b/src/test/ui/svh/svh-change-trait-bound.stderr
@@ -11,3 +11,4 @@ LL | extern crate b;
 
 error: aborting due to previous error
 
+For more information about this error, try `rustc --explain E0460`.
diff --git a/src/test/ui/svh/svh-change-type-arg.stderr b/src/test/ui/svh/svh-change-type-arg.stderr
index f09babf93fd..eef85aa9546 100644
--- a/src/test/ui/svh/svh-change-type-arg.stderr
+++ b/src/test/ui/svh/svh-change-type-arg.stderr
@@ -11,3 +11,4 @@ LL | extern crate b;
 
 error: aborting due to previous error
 
+For more information about this error, try `rustc --explain E0460`.
diff --git a/src/test/ui/svh/svh-change-type-ret.stderr b/src/test/ui/svh/svh-change-type-ret.stderr
index 0998cd4b549..247f74e50df 100644
--- a/src/test/ui/svh/svh-change-type-ret.stderr
+++ b/src/test/ui/svh/svh-change-type-ret.stderr
@@ -11,3 +11,4 @@ LL | extern crate b;
 
 error: aborting due to previous error
 
+For more information about this error, try `rustc --explain E0460`.
diff --git a/src/test/ui/svh/svh-change-type-static.stderr b/src/test/ui/svh/svh-change-type-static.stderr
index 9c48cbd30a5..78b54f227f0 100644
--- a/src/test/ui/svh/svh-change-type-static.stderr
+++ b/src/test/ui/svh/svh-change-type-static.stderr
@@ -11,3 +11,4 @@ LL | extern crate b;
 
 error: aborting due to previous error
 
+For more information about this error, try `rustc --explain E0460`.
diff --git a/src/test/ui/svh/svh-use-trait.stderr b/src/test/ui/svh/svh-use-trait.stderr
index 5780cfef357..d8a81864dca 100644
--- a/src/test/ui/svh/svh-use-trait.stderr
+++ b/src/test/ui/svh/svh-use-trait.stderr
@@ -11,3 +11,4 @@ LL | extern crate utb;
 
 error: aborting due to previous error
 
+For more information about this error, try `rustc --explain E0460`.
diff --git a/src/test/ui/type-alias-impl-trait/auxiliary/coherence_cross_crate_trait_decl.rs b/src/test/ui/type-alias-impl-trait/auxiliary/coherence_cross_crate_trait_decl.rs
new file mode 100644
index 00000000000..712ed55438e
--- /dev/null
+++ b/src/test/ui/type-alias-impl-trait/auxiliary/coherence_cross_crate_trait_decl.rs
@@ -0,0 +1,9 @@
+pub trait SomeTrait {}
+
+impl SomeTrait for () {}
+
+// Adding this `impl` would cause errors in this crate's dependent,
+// so it would be a breaking change. We explicitly don't add this impl,
+// as the dependent crate already assumes this impl exists and thus already
+// does not compile.
+//impl SomeTrait for i32 {}
diff --git a/src/test/ui/type-alias-impl-trait/coherence_cross_crate.rs b/src/test/ui/type-alias-impl-trait/coherence_cross_crate.rs
new file mode 100644
index 00000000000..a63e0a1ee6f
--- /dev/null
+++ b/src/test/ui/type-alias-impl-trait/coherence_cross_crate.rs
@@ -0,0 +1,24 @@
+// aux-build: coherence_cross_crate_trait_decl.rs
+// This test ensures that adding an `impl SomeTrait for i32` within
+// `coherence_cross_crate_trait_decl` is not a breaking change, by
+// making sure that even without such an impl this test fails to compile.
+
+#![feature(type_alias_impl_trait)]
+
+extern crate coherence_cross_crate_trait_decl;
+
+use coherence_cross_crate_trait_decl::SomeTrait;
+
+trait OtherTrait {}
+
+type Alias = impl SomeTrait;
+
+fn constrain() -> Alias {
+    ()
+}
+
+impl OtherTrait for Alias {}
+impl OtherTrait for i32 {}
+//~^ ERROR: conflicting implementations of trait `OtherTrait` for type `Alias`
+
+fn main() {}
diff --git a/src/test/ui/type-alias-impl-trait/coherence_cross_crate.stderr b/src/test/ui/type-alias-impl-trait/coherence_cross_crate.stderr
new file mode 100644
index 00000000000..63a3ce29cc7
--- /dev/null
+++ b/src/test/ui/type-alias-impl-trait/coherence_cross_crate.stderr
@@ -0,0 +1,13 @@
+error[E0119]: conflicting implementations of trait `OtherTrait` for type `Alias`
+  --> $DIR/coherence_cross_crate.rs:21:1
+   |
+LL | impl OtherTrait for Alias {}
+   | ------------------------- first implementation here
+LL | impl OtherTrait for i32 {}
+   | ^^^^^^^^^^^^^^^^^^^^^^^ conflicting implementation for `Alias`
+   |
+   = note: upstream crates may add a new impl of trait `coherence_cross_crate_trait_decl::SomeTrait` for type `i32` in future versions
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0119`.