Auto merge of #68142 - Centril:rollup-dl232e9, r=Centril

Rollup of 6 pull requests

Successful merges:

 - #67494 (Constify more of alloc::Layout)
 - #67867 (Correctly check for opaque types in `assoc_ty_def`)
 - #67948 (Galloping search for binary_search_util)
 - #68045 (Move more of `rustc::lint` into `rustc_lint`)
 - #68089 (Unstabilize `Vec::remove_item`)
 - #68108 (Add suggestions when encountering chained comparisons)

Failed merges:

r? @ghost

14 files changed, 299 insertions, 35 deletions

diff --git a/src/test/ui-fulldeps/auxiliary/issue-40001-plugin.rs b/src/test/ui-fulldeps/auxiliary/issue-40001-plugin.rs
index abb2e93757e..725c350fe4e 100644
--- a/src/test/ui-fulldeps/auxiliary/issue-40001-plugin.rs
+++ b/src/test/ui-fulldeps/auxiliary/issue-40001-plugin.rs
@@ -1,17 +1,17 @@
 #![feature(box_syntax, plugin, plugin_registrar, rustc_private)]
 #![crate_type = "dylib"]
 
-#[macro_use] extern crate rustc;
-#[macro_use] extern crate rustc_session;
 extern crate rustc_driver;
 extern crate rustc_hir;
+#[macro_use] extern crate rustc_lint;
+#[macro_use] extern crate rustc_session;
 extern crate rustc_span;
 extern crate syntax;
 
 use rustc_hir::intravisit;
 use rustc_hir as hir;
 use rustc_hir::Node;
-use rustc::lint::{LateContext, LintPass, LintArray, LateLintPass, LintContext};
+use rustc_lint::{LateContext, LintPass, LintArray, LateLintPass, LintContext};
 use rustc_driver::plugin::Registry;
 use rustc_span::source_map;
 use syntax::print::pprust;
diff --git a/src/test/ui-fulldeps/auxiliary/lint-for-crate-rpass.rs b/src/test/ui-fulldeps/auxiliary/lint-for-crate-rpass.rs
index 4ccbe8a3c0e..98963a180c8 100644
--- a/src/test/ui-fulldeps/auxiliary/lint-for-crate-rpass.rs
+++ b/src/test/ui-fulldeps/auxiliary/lint-for-crate-rpass.rs
@@ -2,14 +2,14 @@
 
 #![feature(plugin_registrar, rustc_private)]
 #![feature(box_syntax)]
-#[macro_use] extern crate rustc;
-#[macro_use] extern crate rustc_session;
 extern crate rustc_driver;
 extern crate rustc_hir;
 extern crate rustc_span;
+#[macro_use] extern crate rustc_lint;
+#[macro_use] extern crate rustc_session;
 extern crate syntax;
 
-use rustc::lint::{LateContext, LintContext, LintPass, LateLintPass};
+use rustc_lint::{LateContext, LintContext, LintPass, LateLintPass};
 use rustc_driver::plugin::Registry;
 use rustc_span::symbol::Symbol;
 use syntax::attr;
diff --git a/src/test/ui-fulldeps/auxiliary/lint-for-crate.rs b/src/test/ui-fulldeps/auxiliary/lint-for-crate.rs
index 360bffaa46f..589477da625 100644
--- a/src/test/ui-fulldeps/auxiliary/lint-for-crate.rs
+++ b/src/test/ui-fulldeps/auxiliary/lint-for-crate.rs
@@ -3,14 +3,14 @@
 #![feature(plugin_registrar, rustc_private)]
 #![feature(box_syntax)]
 
-#[macro_use] extern crate rustc;
-#[macro_use] extern crate rustc_session;
 extern crate rustc_driver;
 extern crate rustc_hir;
+#[macro_use] extern crate rustc_lint;
+#[macro_use] extern crate rustc_session;
 extern crate rustc_span;
 extern crate syntax;
 
-use rustc::lint::{LateContext, LintContext, LintPass, LateLintPass, LintArray};
+use rustc_lint::{LateContext, LintContext, LintPass, LateLintPass, LintArray};
 use rustc_driver::plugin::Registry;
 use rustc_span::symbol::Symbol;
 use syntax::attr;
diff --git a/src/test/ui-fulldeps/auxiliary/lint-group-plugin-test.rs b/src/test/ui-fulldeps/auxiliary/lint-group-plugin-test.rs
index 786c699947e..2cc288c21e6 100644
--- a/src/test/ui-fulldeps/auxiliary/lint-group-plugin-test.rs
+++ b/src/test/ui-fulldeps/auxiliary/lint-group-plugin-test.rs
@@ -4,12 +4,12 @@
 #![feature(box_syntax, rustc_private)]
 
 // Load rustc as a plugin to get macros.
-#[macro_use] extern crate rustc;
-#[macro_use] extern crate rustc_session;
 extern crate rustc_driver;
 extern crate rustc_hir;
+#[macro_use] extern crate rustc_lint;
+#[macro_use] extern crate rustc_session;
 
-use rustc::lint::{LateContext, LintContext, LintPass, LateLintPass, LintArray, LintId};
+use rustc_lint::{LateContext, LintContext, LintPass, LateLintPass, LintArray, LintId};
 use rustc_driver::plugin::Registry;
 
 declare_lint!(TEST_LINT, Warn, "Warn about items named 'lintme'");
diff --git a/src/test/ui-fulldeps/auxiliary/lint-plugin-test.rs b/src/test/ui-fulldeps/auxiliary/lint-plugin-test.rs
index bb96dba21fc..c704701cc48 100644
--- a/src/test/ui-fulldeps/auxiliary/lint-plugin-test.rs
+++ b/src/test/ui-fulldeps/auxiliary/lint-plugin-test.rs
@@ -6,11 +6,11 @@
 extern crate syntax;
 
 // Load rustc as a plugin to get macros
-#[macro_use] extern crate rustc;
-#[macro_use] extern crate rustc_session;
 extern crate rustc_driver;
+#[macro_use] extern crate rustc_lint;
+#[macro_use] extern crate rustc_session;
 
-use rustc::lint::{EarlyContext, LintContext, LintPass, EarlyLintPass, LintArray};
+use rustc_lint::{EarlyContext, LintContext, LintPass, EarlyLintPass, LintArray};
 use rustc_driver::plugin::Registry;
 use syntax::ast;
 declare_lint!(TEST_LINT, Warn, "Warn about items named 'lintme'");
diff --git a/src/test/ui-fulldeps/auxiliary/lint-tool-test.rs b/src/test/ui-fulldeps/auxiliary/lint-tool-test.rs
index 17049098137..fa545ddc2bc 100644
--- a/src/test/ui-fulldeps/auxiliary/lint-tool-test.rs
+++ b/src/test/ui-fulldeps/auxiliary/lint-tool-test.rs
@@ -4,11 +4,11 @@
 extern crate syntax;
 
 // Load rustc as a plugin to get macros
-#[macro_use] extern crate rustc;
-#[macro_use] extern crate rustc_session;
 extern crate rustc_driver;
+#[macro_use] extern crate rustc_lint;
+#[macro_use] extern crate rustc_session;
 
-use rustc::lint::{EarlyContext, EarlyLintPass, LintArray, LintContext, LintPass, LintId};
+use rustc_lint::{EarlyContext, EarlyLintPass, LintArray, LintContext, LintPass, LintId};
 use rustc_driver::plugin::Registry;
 use syntax::ast;
 declare_tool_lint!(pub clippy::TEST_LINT, Warn, "Warn about stuff");
diff --git a/src/test/ui/did_you_mean/issue-40396.rs b/src/test/ui/did_you_mean/issue-40396.rs
index 18933552054..e4e94bb9492 100644
--- a/src/test/ui/did_you_mean/issue-40396.rs
+++ b/src/test/ui/did_you_mean/issue-40396.rs
@@ -1,8 +1,8 @@
 fn main() {
     (0..13).collect<Vec<i32>>();
-    //~^ ERROR chained comparison
+    //~^ ERROR comparison operators cannot be chained
     Vec<i32>::new();
-    //~^ ERROR chained comparison
+    //~^ ERROR comparison operators cannot be chained
     (0..13).collect<Vec<i32>();
-    //~^ ERROR chained comparison
+    //~^ ERROR comparison operators cannot be chained
 }
diff --git a/src/test/ui/did_you_mean/issue-40396.stderr b/src/test/ui/did_you_mean/issue-40396.stderr
index 749d1093cca..f952136a7bf 100644
--- a/src/test/ui/did_you_mean/issue-40396.stderr
+++ b/src/test/ui/did_you_mean/issue-40396.stderr
@@ -1,15 +1,23 @@
-error: chained comparison operators require parentheses
+error: comparison operators cannot be chained
   --> $DIR/issue-40396.rs:2:20
    |
 LL |     (0..13).collect<Vec<i32>>();
    |                    ^^^^^
    |
+help: split the comparison into two...
+   |
+LL |     (0..13).collect < Vec && Vec <i32>>();
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+help: ...or parenthesize one of the comparisons
+   |
+LL |     ((0..13).collect < Vec) <i32>>();
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^
 help: use `::<...>` instead of `<...>` to specify type arguments
    |
 LL |     (0..13).collect::<Vec<i32>>();
    |                    ^^
 
-error: chained comparison operators require parentheses
+error: comparison operators cannot be chained
   --> $DIR/issue-40396.rs:4:8
    |
 LL |     Vec<i32>::new();
@@ -20,12 +28,20 @@ help: use `::<...>` instead of `<...>` to specify type arguments
 LL |     Vec::<i32>::new();
    |        ^^
 
-error: chained comparison operators require parentheses
+error: comparison operators cannot be chained
   --> $DIR/issue-40396.rs:6:20
    |
 LL |     (0..13).collect<Vec<i32>();
    |                    ^^^^^
    |
+help: split the comparison into two...
+   |
+LL |     (0..13).collect < Vec && Vec <i32>();
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+help: ...or parenthesize one of the comparisons
+   |
+LL |     ((0..13).collect < Vec) <i32>();
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^
 help: use `::<...>` instead of `<...>` to specify type arguments
    |
 LL |     (0..13).collect::<Vec<i32>();
diff --git a/src/test/ui/parser/chained-comparison-suggestion.rs b/src/test/ui/parser/chained-comparison-suggestion.rs
new file mode 100644
index 00000000000..0431196f174
--- /dev/null
+++ b/src/test/ui/parser/chained-comparison-suggestion.rs
@@ -0,0 +1,40 @@
+// Check that we get nice suggestions when attempting a chained comparison.
+
+fn comp1() {
+    1 < 2 <= 3; //~ ERROR comparison operators cannot be chained
+    //~^ ERROR mismatched types
+}
+
+fn comp2() {
+    1 < 2 < 3; //~ ERROR comparison operators cannot be chained
+}
+
+fn comp3() {
+    1 <= 2 < 3; //~ ERROR comparison operators cannot be chained
+    //~^ ERROR mismatched types
+}
+
+fn comp4() {
+    1 <= 2 <= 3; //~ ERROR comparison operators cannot be chained
+    //~^ ERROR mismatched types
+}
+
+fn comp5() {
+    1 > 2 >= 3; //~ ERROR comparison operators cannot be chained
+    //~^ ERROR mismatched types
+}
+
+fn comp6() {
+    1 > 2 > 3; //~ ERROR comparison operators cannot be chained
+}
+
+fn comp7() {
+    1 >= 2 > 3; //~ ERROR comparison operators cannot be chained
+}
+
+fn comp8() {
+    1 >= 2 >= 3; //~ ERROR comparison operators cannot be chained
+    //~^ ERROR mismatched types
+}
+
+fn main() {}
diff --git a/src/test/ui/parser/chained-comparison-suggestion.stderr b/src/test/ui/parser/chained-comparison-suggestion.stderr
new file mode 100644
index 00000000000..5c10a4599dd
--- /dev/null
+++ b/src/test/ui/parser/chained-comparison-suggestion.stderr
@@ -0,0 +1,159 @@
+error: comparison operators cannot be chained
+  --> $DIR/chained-comparison-suggestion.rs:4:7
+   |
+LL |     1 < 2 <= 3;
+   |       ^^^^^^
+   |
+help: split the comparison into two...
+   |
+LL |     1 < 2 && 2 <= 3;
+   |     ^^^^^^^^^^^^^
+help: ...or parenthesize one of the comparisons
+   |
+LL |     (1 < 2) <= 3;
+   |     ^^^^^^^^^^
+
+error: comparison operators cannot be chained
+  --> $DIR/chained-comparison-suggestion.rs:9:7
+   |
+LL |     1 < 2 < 3;
+   |       ^^^^^
+   |
+   = help: use `::<...>` instead of `<...>` to specify type arguments
+   = help: or use `(...)` if you meant to specify fn arguments
+help: split the comparison into two...
+   |
+LL |     1 < 2 && 2 < 3;
+   |     ^^^^^^^^^^^^
+help: ...or parenthesize one of the comparisons
+   |
+LL |     (1 < 2) < 3;
+   |     ^^^^^^^^^
+
+error: comparison operators cannot be chained
+  --> $DIR/chained-comparison-suggestion.rs:13:7
+   |
+LL |     1 <= 2 < 3;
+   |       ^^^^^^
+   |
+help: split the comparison into two...
+   |
+LL |     1 <= 2 && 2 < 3;
+   |     ^^^^^^^^^^^^^
+help: ...or parenthesize one of the comparisons
+   |
+LL |     (1 <= 2) < 3;
+   |     ^^^^^^^^^^
+
+error: comparison operators cannot be chained
+  --> $DIR/chained-comparison-suggestion.rs:18:7
+   |
+LL |     1 <= 2 <= 3;
+   |       ^^^^^^^
+   |
+help: split the comparison into two...
+   |
+LL |     1 <= 2 && 2 <= 3;
+   |     ^^^^^^^^^^^^^^
+help: ...or parenthesize one of the comparisons
+   |
+LL |     (1 <= 2) <= 3;
+   |     ^^^^^^^^^^^
+
+error: comparison operators cannot be chained
+  --> $DIR/chained-comparison-suggestion.rs:23:7
+   |
+LL |     1 > 2 >= 3;
+   |       ^^^^^^
+   |
+help: split the comparison into two...
+   |
+LL |     1 > 2 && 2 >= 3;
+   |     ^^^^^^^^^^^^^
+help: ...or parenthesize one of the comparisons
+   |
+LL |     (1 > 2) >= 3;
+   |     ^^^^^^^^^^
+
+error: comparison operators cannot be chained
+  --> $DIR/chained-comparison-suggestion.rs:28:7
+   |
+LL |     1 > 2 > 3;
+   |       ^^^^^
+   |
+   = help: use `::<...>` instead of `<...>` to specify type arguments
+   = help: or use `(...)` if you meant to specify fn arguments
+help: split the comparison into two...
+   |
+LL |     1 > 2 && 2 > 3;
+   |     ^^^^^^^^^^^^
+help: ...or parenthesize one of the comparisons
+   |
+LL |     (1 > 2) > 3;
+   |     ^^^^^^^^^
+
+error: comparison operators cannot be chained
+  --> $DIR/chained-comparison-suggestion.rs:32:7
+   |
+LL |     1 >= 2 > 3;
+   |       ^^^^^^
+   |
+   = help: use `::<...>` instead of `<...>` to specify type arguments
+   = help: or use `(...)` if you meant to specify fn arguments
+help: split the comparison into two...
+   |
+LL |     1 >= 2 && 2 > 3;
+   |     ^^^^^^^^^^^^^
+help: ...or parenthesize one of the comparisons
+   |
+LL |     (1 >= 2) > 3;
+   |     ^^^^^^^^^^
+
+error: comparison operators cannot be chained
+  --> $DIR/chained-comparison-suggestion.rs:36:7
+   |
+LL |     1 >= 2 >= 3;
+   |       ^^^^^^^
+   |
+help: split the comparison into two...
+   |
+LL |     1 >= 2 && 2 >= 3;
+   |     ^^^^^^^^^^^^^^
+help: ...or parenthesize one of the comparisons
+   |
+LL |     (1 >= 2) >= 3;
+   |     ^^^^^^^^^^^
+
+error[E0308]: mismatched types
+  --> $DIR/chained-comparison-suggestion.rs:4:14
+   |
+LL |     1 < 2 <= 3;
+   |              ^ expected `bool`, found integer
+
+error[E0308]: mismatched types
+  --> $DIR/chained-comparison-suggestion.rs:13:14
+   |
+LL |     1 <= 2 < 3;
+   |              ^ expected `bool`, found integer
+
+error[E0308]: mismatched types
+  --> $DIR/chained-comparison-suggestion.rs:18:15
+   |
+LL |     1 <= 2 <= 3;
+   |               ^ expected `bool`, found integer
+
+error[E0308]: mismatched types
+  --> $DIR/chained-comparison-suggestion.rs:23:14
+   |
+LL |     1 > 2 >= 3;
+   |              ^ expected `bool`, found integer
+
+error[E0308]: mismatched types
+  --> $DIR/chained-comparison-suggestion.rs:36:15
+   |
+LL |     1 >= 2 >= 3;
+   |               ^ expected `bool`, found integer
+
+error: aborting due to 13 previous errors
+
+For more information about this error, try `rustc --explain E0308`.
diff --git a/src/test/ui/parser/require-parens-for-chained-comparison.rs b/src/test/ui/parser/require-parens-for-chained-comparison.rs
index 9c7a25d589a..e27b03dddc5 100644
--- a/src/test/ui/parser/require-parens-for-chained-comparison.rs
+++ b/src/test/ui/parser/require-parens-for-chained-comparison.rs
@@ -3,24 +3,26 @@ struct X;
 
 fn main() {
     false == false == false;
-    //~^ ERROR chained comparison operators require parentheses
+    //~^ ERROR comparison operators cannot be chained
 
     false == 0 < 2;
-    //~^ ERROR chained comparison operators require parentheses
+    //~^ ERROR comparison operators cannot be chained
     //~| ERROR mismatched types
     //~| ERROR mismatched types
 
     f<X>();
-    //~^ ERROR chained comparison operators require parentheses
+    //~^ ERROR comparison operators cannot be chained
     //~| HELP use `::<...>` instead of `<...>` to specify type arguments
 
     f<Result<Option<X>, Option<Option<X>>>(1, 2);
-    //~^ ERROR chained comparison operators require parentheses
+    //~^ ERROR comparison operators cannot be chained
+    //~| HELP split the comparison into two...
+    //~| ...or parenthesize one of the comparisons
     //~| HELP use `::<...>` instead of `<...>` to specify type arguments
 
     use std::convert::identity;
     let _ = identity<u8>;
-    //~^ ERROR chained comparison operators require parentheses
+    //~^ ERROR comparison operators cannot be chained
     //~| HELP use `::<...>` instead of `<...>` to specify type arguments
     //~| HELP or use `(...)` if you meant to specify fn arguments
 }
diff --git a/src/test/ui/parser/require-parens-for-chained-comparison.stderr b/src/test/ui/parser/require-parens-for-chained-comparison.stderr
index bece9a38800..44edf2de7f8 100644
--- a/src/test/ui/parser/require-parens-for-chained-comparison.stderr
+++ b/src/test/ui/parser/require-parens-for-chained-comparison.stderr
@@ -1,16 +1,16 @@
-error: chained comparison operators require parentheses
+error: comparison operators cannot be chained
   --> $DIR/require-parens-for-chained-comparison.rs:5:11
    |
 LL |     false == false == false;
    |           ^^^^^^^^^^^
 
-error: chained comparison operators require parentheses
+error: comparison operators cannot be chained
   --> $DIR/require-parens-for-chained-comparison.rs:8:11
    |
 LL |     false == 0 < 2;
    |           ^^^^^^
 
-error: chained comparison operators require parentheses
+error: comparison operators cannot be chained
   --> $DIR/require-parens-for-chained-comparison.rs:13:6
    |
 LL |     f<X>();
@@ -21,19 +21,27 @@ help: use `::<...>` instead of `<...>` to specify type arguments
 LL |     f::<X>();
    |      ^^
 
-error: chained comparison operators require parentheses
+error: comparison operators cannot be chained
   --> $DIR/require-parens-for-chained-comparison.rs:17:6
    |
 LL |     f<Result<Option<X>, Option<Option<X>>>(1, 2);
    |      ^^^^^^^^
    |
+help: split the comparison into two...
+   |
+LL |     f < Result && Result <Option<X>, Option<Option<X>>>(1, 2);
+   |     ^^^^^^^^^^^^^^^^^^^^^^
+help: ...or parenthesize one of the comparisons
+   |
+LL |     (f < Result) <Option<X>, Option<Option<X>>>(1, 2);
+   |     ^^^^^^^^^^^^^^
 help: use `::<...>` instead of `<...>` to specify type arguments
    |
 LL |     f::<Result<Option<X>, Option<Option<X>>>(1, 2);
    |      ^^
 
-error: chained comparison operators require parentheses
-  --> $DIR/require-parens-for-chained-comparison.rs:22:21
+error: comparison operators cannot be chained
+  --> $DIR/require-parens-for-chained-comparison.rs:24:21
    |
 LL |     let _ = identity<u8>;
    |                     ^^^^
diff --git a/src/test/ui/type-alias-impl-trait/incoherent-assoc-imp-trait.rs b/src/test/ui/type-alias-impl-trait/incoherent-assoc-imp-trait.rs
new file mode 100644
index 00000000000..c46c4715924
--- /dev/null
+++ b/src/test/ui/type-alias-impl-trait/incoherent-assoc-imp-trait.rs
@@ -0,0 +1,16 @@
+// Regression test for issue 67856
+
+#![feature(unboxed_closures)]
+#![feature(type_alias_impl_trait)]
+#![feature(fn_traits)]
+
+trait MyTrait {}
+impl MyTrait for () {}
+
+impl<F> FnOnce<()> for &F {
+    //~^ ERROR conflicting implementations
+    //~| ERROR type parameter `F` must be used
+    type Output = impl MyTrait;
+    extern "rust-call" fn call_once(self, _: ()) -> Self::Output {}
+}
+fn main() {}
diff --git a/src/test/ui/type-alias-impl-trait/incoherent-assoc-imp-trait.stderr b/src/test/ui/type-alias-impl-trait/incoherent-assoc-imp-trait.stderr
new file mode 100644
index 00000000000..f8e1e55f23f
--- /dev/null
+++ b/src/test/ui/type-alias-impl-trait/incoherent-assoc-imp-trait.stderr
@@ -0,0 +1,23 @@
+error[E0119]: conflicting implementations of trait `std::ops::FnOnce<()>` for type `&_`:
+  --> $DIR/incoherent-assoc-imp-trait.rs:10:1
+   |
+LL | impl<F> FnOnce<()> for &F {
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+   = note: conflicting implementation in crate `core`:
+           - impl<A, F> std::ops::FnOnce<A> for &F
+             where F: std::ops::Fn<A>, F: ?Sized;
+
+error[E0210]: type parameter `F` must be used as the type parameter for some local type (e.g., `MyStruct<F>`)
+  --> $DIR/incoherent-assoc-imp-trait.rs:10:6
+   |
+LL | impl<F> FnOnce<()> for &F {
+   |      ^ type parameter `F` must be used as the type parameter for some local type
+   |
+   = note: implementing a foreign trait is only possible if at least one of the types for which is it implemented is local
+   = note: only traits defined in the current crate can be implemented for a type parameter
+
+error: aborting due to 2 previous errors
+
+Some errors have detailed explanations: E0119, E0210.
+For more information about an error, try `rustc --explain E0119`.