Merge branch 'master' into stabilise/termination-test

44 files changed, 860 insertions, 79 deletions

diff --git a/src/test/compile-fail/auxiliary/some-panic-impl.rs b/src/test/compile-fail/auxiliary/some-panic-impl.rs
new file mode 100644
index 00000000000..db16ac325ac
--- /dev/null
+++ b/src/test/compile-fail/auxiliary/some-panic-impl.rs
@@ -0,0 +1,22 @@
+// Copyright 2018 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+// no-prefer-dynamic
+
+#![crate_type = "rlib"]
+#![feature(panic_implementation)]
+#![no_std]
+
+use core::panic::PanicInfo;
+
+#[panic_implementation]
+fn panic(info: &PanicInfo) -> ! {
+    loop {}
+}
diff --git a/src/test/compile-fail/duplicate_entry_error.rs b/src/test/compile-fail/duplicate_entry_error.rs
index 485519e8c3d..176aa7cca53 100644
--- a/src/test/compile-fail/duplicate_entry_error.rs
+++ b/src/test/compile-fail/duplicate_entry_error.rs
@@ -14,9 +14,11 @@
 
 #![feature(lang_items)]
 
-#[lang = "panic_fmt"]
-fn panic_fmt() -> ! {
-//~^ ERROR: duplicate lang item found: `panic_fmt`.
+use std::panic::PanicInfo;
+
+#[lang = "panic_impl"]
+fn panic_impl(info: &PanicInfo) -> ! {
+//~^ ERROR: duplicate lang item found: `panic_impl`.
     loop {}
 }
 
diff --git a/src/test/compile-fail/edition-extern-crate-allowed.rs b/src/test/compile-fail/edition-extern-crate-allowed.rs
index 286ee896161..7368564e250 100644
--- a/src/test/compile-fail/edition-extern-crate-allowed.rs
+++ b/src/test/compile-fail/edition-extern-crate-allowed.rs
@@ -12,8 +12,9 @@
 // compile-flags: --edition 2015
 // compile-pass
 
-#![deny(rust_2018_idioms)]
+#![warn(rust_2018_idioms)]
 
 extern crate edition_extern_crate_allowed;
+//~^ WARNING unused extern crate
 
 fn main() {}
diff --git a/src/test/compile-fail/feature-gate-panic-implementation.rs b/src/test/compile-fail/feature-gate-panic-implementation.rs
new file mode 100644
index 00000000000..ae9fbc7b13b
--- /dev/null
+++ b/src/test/compile-fail/feature-gate-panic-implementation.rs
@@ -0,0 +1,21 @@
+// Copyright 2018 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+// compile-flags:-C panic=abort
+
+#![no_std]
+#![no_main]
+
+use core::panic::PanicInfo;
+
+#[panic_implementation] //~ ERROR #[panic_implementation] is an unstable feature (see issue #44489)
+fn panic(info: &PanicInfo) -> ! {
+    loop {}
+}
diff --git a/src/test/compile-fail/no_owned_box_lang_item.rs b/src/test/compile-fail/no_owned_box_lang_item.rs
index 72eb687adc6..1c2bf1573dc 100644
--- a/src/test/compile-fail/no_owned_box_lang_item.rs
+++ b/src/test/compile-fail/no_owned_box_lang_item.rs
@@ -21,4 +21,4 @@ fn main() {
 
 #[lang = "eh_personality"] extern fn eh_personality() {}
 #[lang = "eh_unwind_resume"] extern fn eh_unwind_resume() {}
-#[lang = "panic_fmt"] fn panic_fmt() -> ! { loop {} }
+#[lang = "panic_impl"] fn panic_impl() -> ! { loop {} }
diff --git a/src/test/compile-fail/panic-implementation-bad-signature-1.rs b/src/test/compile-fail/panic-implementation-bad-signature-1.rs
new file mode 100644
index 00000000000..fec11fdbd7b
--- /dev/null
+++ b/src/test/compile-fail/panic-implementation-bad-signature-1.rs
@@ -0,0 +1,24 @@
+// Copyright 2018 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+// compile-flags:-C panic=abort
+
+#![feature(panic_implementation)]
+#![no_std]
+#![no_main]
+
+use core::panic::PanicInfo;
+
+#[panic_implementation]
+fn panic(
+    info: PanicInfo, //~ ERROR argument should be `&PanicInfo`
+) -> () //~ ERROR return type should be `!`
+{
+}
diff --git a/src/test/compile-fail/panic-implementation-bad-signature-2.rs b/src/test/compile-fail/panic-implementation-bad-signature-2.rs
new file mode 100644
index 00000000000..2a628c05699
--- /dev/null
+++ b/src/test/compile-fail/panic-implementation-bad-signature-2.rs
@@ -0,0 +1,25 @@
+// Copyright 2018 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+// compile-flags:-C panic=abort
+
+#![feature(panic_implementation)]
+#![no_std]
+#![no_main]
+
+use core::panic::PanicInfo;
+
+#[panic_implementation]
+fn panic(
+    info: &'static PanicInfo, //~ ERROR argument should be `&PanicInfo`
+) -> !
+{
+    loop {}
+}
diff --git a/src/test/compile-fail/panic-implementation-bad-signature-3.rs b/src/test/compile-fail/panic-implementation-bad-signature-3.rs
new file mode 100644
index 00000000000..29337025b70
--- /dev/null
+++ b/src/test/compile-fail/panic-implementation-bad-signature-3.rs
@@ -0,0 +1,22 @@
+// Copyright 2018 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+// compile-flags:-C panic=abort
+
+#![feature(panic_implementation)]
+#![no_std]
+#![no_main]
+
+use core::panic::PanicInfo;
+
+#[panic_implementation]
+fn panic() -> ! { //~ ERROR function should have one argument
+    loop {}
+}
diff --git a/src/test/compile-fail/panic-implementation-bad-signature-4.rs b/src/test/compile-fail/panic-implementation-bad-signature-4.rs
new file mode 100644
index 00000000000..d5f942ba2d6
--- /dev/null
+++ b/src/test/compile-fail/panic-implementation-bad-signature-4.rs
@@ -0,0 +1,23 @@
+// Copyright 2018 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+// compile-flags:-C panic=abort
+
+#![feature(panic_implementation)]
+#![no_std]
+#![no_main]
+
+use core::panic::PanicInfo;
+
+#[panic_implementation]
+fn panic<T>(pi: &PanicInfo) -> ! {
+    //~^ ERROR `#[panic_implementation]` function should have no type parameters
+    loop {}
+}
diff --git a/src/test/compile-fail/panic-implementation-duplicate.rs b/src/test/compile-fail/panic-implementation-duplicate.rs
new file mode 100644
index 00000000000..017113af409
--- /dev/null
+++ b/src/test/compile-fail/panic-implementation-duplicate.rs
@@ -0,0 +1,28 @@
+// Copyright 2018 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+// compile-flags:-C panic=abort
+
+#![feature(lang_items)]
+#![feature(panic_implementation)]
+#![no_std]
+#![no_main]
+
+use core::panic::PanicInfo;
+
+#[panic_implementation]
+fn panic(info: &PanicInfo) -> ! {
+    loop {}
+}
+
+#[lang = "panic_impl"]
+fn panic2(info: &PanicInfo) -> ! { //~ ERROR duplicate lang item found: `panic_impl`.
+    loop {}
+}
diff --git a/src/test/compile-fail/panic-implementation-requires-panic-info.rs b/src/test/compile-fail/panic-implementation-requires-panic-info.rs
new file mode 100644
index 00000000000..597f44d9832
--- /dev/null
+++ b/src/test/compile-fail/panic-implementation-requires-panic-info.rs
@@ -0,0 +1,26 @@
+// Copyright 2018 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+// compile-flags:-C panic=abort
+// error-pattern: language item required, but not found: `panic_info`
+
+#![feature(lang_items)]
+#![feature(no_core)]
+#![feature(panic_implementation)]
+#![no_core]
+#![no_main]
+
+#[panic_implementation]
+fn panic() -> ! {
+    loop {}
+}
+
+#[lang = "sized"]
+trait Sized {}
diff --git a/src/test/compile-fail/panic-implementation-std.rs b/src/test/compile-fail/panic-implementation-std.rs
new file mode 100644
index 00000000000..f25cd3605c1
--- /dev/null
+++ b/src/test/compile-fail/panic-implementation-std.rs
@@ -0,0 +1,22 @@
+// Copyright 2018 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+// error-pattern: duplicate lang item found: `panic_impl`.
+
+#![feature(panic_implementation)]
+
+use std::panic::PanicInfo;
+
+#[panic_implementation]
+fn panic(info: PanicInfo) -> ! {
+    loop {}
+}
+
+fn main() {}
diff --git a/src/test/compile-fail/panic-implementation-twice.rs b/src/test/compile-fail/panic-implementation-twice.rs
new file mode 100644
index 00000000000..78dc545c036
--- /dev/null
+++ b/src/test/compile-fail/panic-implementation-twice.rs
@@ -0,0 +1,29 @@
+// Copyright 2018 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+// aux-build:some-panic-impl.rs
+
+#![feature(panic_implementation)]
+#![feature(lang_items)]
+#![no_std]
+#![no_main]
+
+extern crate some_panic_impl;
+
+use core::panic::PanicInfo;
+
+#[panic_implementation]
+fn panic(info: &PanicInfo) -> ! {
+    //~^ error duplicate lang item found: `panic_impl`
+    loop {}
+}
+
+#[lang = "eh_personality"]
+fn eh() {}
diff --git a/src/test/compile-fail/panic-runtime/auxiliary/panic-runtime-lang-items.rs b/src/test/compile-fail/panic-runtime/auxiliary/panic-runtime-lang-items.rs
index fbf70b3d3fe..d9848a554ab 100644
--- a/src/test/compile-fail/panic-runtime/auxiliary/panic-runtime-lang-items.rs
+++ b/src/test/compile-fail/panic-runtime/auxiliary/panic-runtime-lang-items.rs
@@ -15,8 +15,10 @@
 #![no_std]
 #![feature(lang_items)]
 
-#[lang = "panic_fmt"]
-fn panic_fmt() {}
+use core::panic::PanicInfo;
+
+#[lang = "panic_impl"]
+fn panic_impl(info: &PanicInfo) -> ! { loop {} }
 #[lang = "eh_personality"]
 fn eh_personality() {}
 #[lang = "eh_unwind_resume"]
diff --git a/src/test/compile-fail/weak-lang-item.rs b/src/test/compile-fail/weak-lang-item.rs
index 8579611b938..7b988c3595f 100644
--- a/src/test/compile-fail/weak-lang-item.rs
+++ b/src/test/compile-fail/weak-lang-item.rs
@@ -9,7 +9,7 @@
 // except according to those terms.
 
 // aux-build:weak-lang-items.rs
-// error-pattern: language item required, but not found: `panic_fmt`
+// error-pattern: language item required, but not found: `panic_impl`
 // error-pattern: language item required, but not found: `eh_personality`
 // ignore-wasm32-bare compiled with panic=abort, personality not required
 
diff --git a/src/test/run-make-fulldeps/issue-36710/Makefile b/src/test/run-make-fulldeps/issue-36710/Makefile
new file mode 100644
index 00000000000..928bdf532df
--- /dev/null
+++ b/src/test/run-make-fulldeps/issue-36710/Makefile
@@ -0,0 +1,21 @@
+-include ../tools.mk
+
+ifeq (musl,$(findstring musl,$(TARGET)))
+all: skip
+else
+all: test
+endif
+
+test: foo
+	$(call RUN,foo)
+
+skip:
+	echo "expected failure"
+
+foo: foo.rs $(call NATIVE_STATICLIB,foo)
+	$(RUSTC) $< -lfoo $(EXTRACXXFLAGS)
+
+$(TMPDIR)/libfoo.o: foo.cpp
+	$(call COMPILE_OBJ_CXX,$@,$<)
+
+.PHONY: all test skip
diff --git a/src/test/run-make-fulldeps/issue-36710/foo.cpp b/src/test/run-make-fulldeps/issue-36710/foo.cpp
new file mode 100644
index 00000000000..fbd0ead7a50
--- /dev/null
+++ b/src/test/run-make-fulldeps/issue-36710/foo.cpp
@@ -0,0 +1,25 @@
+// Copyright 2018 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+#include <stdint.h>
+
+struct A {
+    A() { v = 1234; }
+    ~A() { v = 1; }
+    uint32_t v;
+};
+
+A a;
+
+extern "C" {
+    uint32_t get() {
+        return a.v;
+    }
+}
diff --git a/src/test/run-make-fulldeps/issue-36710/foo.rs b/src/test/run-make-fulldeps/issue-36710/foo.rs
new file mode 100644
index 00000000000..6e50566ddfd
--- /dev/null
+++ b/src/test/run-make-fulldeps/issue-36710/foo.rs
@@ -0,0 +1,18 @@
+// Copyright 2018 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+// Tests that linking to C++ code with global destructors works.
+
+extern { fn get() -> u32; }
+
+fn main() {
+    let i = unsafe { get() };
+    assert_eq!(i, 1234);
+}
diff --git a/src/test/run-make-fulldeps/panic-impl-transitive/Makefile b/src/test/run-make-fulldeps/panic-impl-transitive/Makefile
new file mode 100644
index 00000000000..1714578b2ba
--- /dev/null
+++ b/src/test/run-make-fulldeps/panic-impl-transitive/Makefile
@@ -0,0 +1,7 @@
+-include ../../run-make-fulldeps/tools.mk
+
+# NOTE we use --emit=llvm-ir to avoid running the linker (linking will fail because there's no main
+# in this crate)
+all:
+	$(RUSTC) panic-impl-provider.rs
+	$(RUSTC) panic-impl-consumer.rs -C panic=abort --emit=llvm-ir -L $(TMPDIR)
diff --git a/src/test/run-make-fulldeps/panic-impl-transitive/panic-impl-consumer.rs b/src/test/run-make-fulldeps/panic-impl-transitive/panic-impl-consumer.rs
new file mode 100644
index 00000000000..592fab8be85
--- /dev/null
+++ b/src/test/run-make-fulldeps/panic-impl-transitive/panic-impl-consumer.rs
@@ -0,0 +1,15 @@
+// Copyright 2018 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+#![no_std]
+#![no_main]
+
+// this crate provides the `panic_impl` lang item so we don't need to define it here
+extern crate panic_impl_provider;
diff --git a/src/test/run-make-fulldeps/panic-impl-transitive/panic-impl-provider.rs b/src/test/run-make-fulldeps/panic-impl-transitive/panic-impl-provider.rs
new file mode 100644
index 00000000000..46cdf2e2fa5
--- /dev/null
+++ b/src/test/run-make-fulldeps/panic-impl-transitive/panic-impl-provider.rs
@@ -0,0 +1,20 @@
+// Copyright 2018 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+#![crate_type = "rlib"]
+#![feature(panic_implementation)]
+#![no_std]
+
+use core::panic::PanicInfo;
+
+#[panic_implementation]
+fn panic(info: &PanicInfo) -> ! {
+    loop {}
+}
diff --git a/src/test/run-make-fulldeps/tools.mk b/src/test/run-make-fulldeps/tools.mk
index af1707de6c0..3de358fa500 100644
--- a/src/test/run-make-fulldeps/tools.mk
+++ b/src/test/run-make-fulldeps/tools.mk
@@ -59,12 +59,14 @@ endif
 
 ifdef IS_MSVC
 COMPILE_OBJ = $(CC) -c -Fo:`cygpath -w $(1)` $(2)
+COMPILE_OBJ_CXX = $(CXX) -c -Fo:`cygpath -w $(1)` $(2)
 NATIVE_STATICLIB_FILE = $(1).lib
 NATIVE_STATICLIB = $(TMPDIR)/$(call NATIVE_STATICLIB_FILE,$(1))
 OUT_EXE=-Fe:`cygpath -w $(TMPDIR)/$(call BIN,$(1))` \
 	-Fo:`cygpath -w $(TMPDIR)/$(1).obj`
 else
 COMPILE_OBJ = $(CC) -c -o $(1) $(2)
+COMPILE_OBJ_CXX = $(CXX) -c -o $(1) $(2)
 NATIVE_STATICLIB_FILE = lib$(1).a
 NATIVE_STATICLIB = $(call STATICLIB,$(1))
 OUT_EXE=-o $(TMPDIR)/$(1)
diff --git a/src/test/run-pass/const-endianess.rs b/src/test/run-pass/const-endianess.rs
new file mode 100644
index 00000000000..fa34b49210a
--- /dev/null
+++ b/src/test/run-pass/const-endianess.rs
@@ -0,0 +1,32 @@
+// Copyright 2018 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+#![feature(const_int_ops)]
+#![feature(test)]
+
+extern crate test;
+use test::black_box as b;
+
+const BE_U32: u32 = 55u32.to_be();
+const LE_U32: u32 = 55u32.to_le();
+
+
+fn main() {
+    assert_eq!(BE_U32, b(55u32).to_be());
+    assert_eq!(LE_U32, b(55u32).to_le());
+
+    #[cfg(not(target_arch = "asmjs"))]
+    {
+        const BE_U128: u128 = 999999u128.to_be();
+        const LE_I128: i128 = -999999i128.to_le();
+        assert_eq!(BE_U128, b(999999u128).to_be());
+        assert_eq!(LE_I128, b(-999999i128).to_le());
+    }
+}
diff --git a/src/test/rustdoc-ui/intra-links-warning.rs b/src/test/rustdoc-ui/intra-links-warning.rs
index 2a00d31e3d7..830aaabf9d2 100644
--- a/src/test/rustdoc-ui/intra-links-warning.rs
+++ b/src/test/rustdoc-ui/intra-links-warning.rs
@@ -10,7 +10,9 @@
 
 // compile-pass
 
-//! Test with [Foo::baz], [Bar::foo], [Uniooon::X]
+//! Test with [Foo::baz], [Bar::foo], ...
+//!
+//! and [Uniooon::X].
 
 pub struct Foo {
     pub bar: usize,
diff --git a/src/test/rustdoc-ui/intra-links-warning.stderr b/src/test/rustdoc-ui/intra-links-warning.stderr
index 67d7bdd02b3..1e8e9f04c26 100644
--- a/src/test/rustdoc-ui/intra-links-warning.stderr
+++ b/src/test/rustdoc-ui/intra-links-warning.stderr
@@ -1,6 +1,39 @@
 warning: [Foo::baz] cannot be resolved, ignoring it...
+  --> $DIR/intra-links-warning.rs:13:1
+   |
+13 | / //! Test with [Foo::baz], [Bar::foo], ...
+14 | | //!
+15 | | //! and [Uniooon::X].
+   | |_____________________^
+   |
+   = note: the link appears in this line:
+           
+            Test with [Foo::baz], [Bar::foo], ...
+                       ^^^^^^^^
 
 warning: [Bar::foo] cannot be resolved, ignoring it...
+  --> $DIR/intra-links-warning.rs:13:1
+   |
+13 | / //! Test with [Foo::baz], [Bar::foo], ...
+14 | | //!
+15 | | //! and [Uniooon::X].
+   | |_____________________^
+   |
+   = note: the link appears in this line:
+           
+            Test with [Foo::baz], [Bar::foo], ...
+                                   ^^^^^^^^
 
 warning: [Uniooon::X] cannot be resolved, ignoring it...
+  --> $DIR/intra-links-warning.rs:13:1
+   |
+13 | / //! Test with [Foo::baz], [Bar::foo], ...
+14 | | //!
+15 | | //! and [Uniooon::X].
+   | |_____________________^
+   |
+   = note: the link appears in this line:
+           
+            and [Uniooon::X].
+                 ^^^^^^^^^^
 
diff --git a/src/test/rustdoc/rustc-macro-crate.rs b/src/test/rustdoc/rustc-macro-crate.rs
index dc28732b55e..d46f9684411 100644
--- a/src/test/rustdoc/rustc-macro-crate.rs
+++ b/src/test/rustdoc/rustc-macro-crate.rs
@@ -9,6 +9,7 @@
 // except according to those terms.
 
 // no-prefer-dynamic
+// ignore-stage1
 
 #![crate_type = "proc-macro"]
 
diff --git a/src/test/rustdoc/trait-attributes.rs b/src/test/rustdoc/trait-attributes.rs
new file mode 100644
index 00000000000..00d10408b4c
--- /dev/null
+++ b/src/test/rustdoc/trait-attributes.rs
@@ -0,0 +1,32 @@
+// Copyright 2018 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+#![crate_name = "foo"]
+
+// ignore-tidy-linelength
+
+pub trait Foo {
+    // @has foo/trait.Foo.html '//h3[@id="tymethod.foo"]//div[@class="docblock attributes"]' '#[must_use]'
+    #[must_use]
+    fn foo();
+}
+
+#[must_use]
+pub struct Bar;
+
+impl Bar {
+    // @has foo/struct.Bar.html '//h4[@id="method.bar"]//div[@class="docblock attributes"]' '#[must_use]'
+    #[must_use]
+    pub fn bar() {}
+
+    // @has foo/struct.Bar.html '//h4[@id="method.bar2"]//div[@class="docblock attributes"]' '#[must_use]'
+    #[must_use]
+    pub fn bar2() {}
+}
diff --git a/src/test/ui-fulldeps/unnecessary-extern-crate.rs b/src/test/ui-fulldeps/unnecessary-extern-crate.rs
index fc6cb6bd053..0811c79b0a4 100644
--- a/src/test/ui-fulldeps/unnecessary-extern-crate.rs
+++ b/src/test/ui-fulldeps/unnecessary-extern-crate.rs
@@ -10,48 +10,90 @@
 
 // compile-flags: --edition 2018
 
-#![deny(unnecessary_extern_crates)]
+#![deny(unused_extern_crates)]
 #![feature(alloc, test, libc)]
 
 extern crate alloc;
-//~^ ERROR `extern crate` is unnecessary in the new edition
+//~^ ERROR unused extern crate
 //~| HELP remove
 extern crate alloc as x;
-//~^ ERROR `extern crate` is unnecessary in the new edition
-//~| HELP use `use`
+//~^ ERROR unused extern crate
+//~| HELP remove
 
 #[macro_use]
 extern crate test;
+
 pub extern crate test as y;
-//~^ ERROR `extern crate` is unnecessary in the new edition
-//~| HELP use `pub use`
+//~^ ERROR `extern crate` is not idiomatic in the new edition
+//~| HELP convert it to a `pub use`
+
 pub extern crate libc;
-//~^ ERROR `extern crate` is unnecessary in the new edition
-//~| HELP use `pub use`
+//~^ ERROR `extern crate` is not idiomatic in the new edition
+//~| HELP convert it to a `pub use`
+
+pub(crate) extern crate libc as a;
+//~^ ERROR `extern crate` is not idiomatic in the new edition
+//~| HELP convert it to a `pub(crate) use`
 
+crate extern crate libc as b;
+//~^ ERROR `extern crate` is not idiomatic in the new edition
+//~| HELP convert it to a `crate use`
 
 mod foo {
+    pub(in crate::foo) extern crate libc as c;
+    //~^ ERROR `extern crate` is not idiomatic in the new edition
+    //~| HELP convert it to a `pub(in crate::foo) use`
+
+    pub(super) extern crate libc as d;
+    //~^ ERROR `extern crate` is not idiomatic in the new edition
+    //~| HELP convert it to a `pub(super) use`
+
     extern crate alloc;
-    //~^ ERROR `extern crate` is unnecessary in the new edition
-    //~| HELP use `use`
+    //~^ ERROR unused extern crate
+    //~| HELP remove
+
     extern crate alloc as x;
-    //~^ ERROR `extern crate` is unnecessary in the new edition
-    //~| HELP use `use`
+    //~^ ERROR unused extern crate
+    //~| HELP remove
+
     pub extern crate test;
-    //~^ ERROR `extern crate` is unnecessary in the new edition
-    //~| HELP use `pub use`
+    //~^ ERROR `extern crate` is not idiomatic in the new edition
+    //~| HELP convert it
+
     pub extern crate test as y;
-    //~^ ERROR `extern crate` is unnecessary in the new edition
-    //~| HELP use `pub use`
+    //~^ ERROR `extern crate` is not idiomatic in the new edition
+    //~| HELP convert it
+
     mod bar {
         extern crate alloc;
-        //~^ ERROR `extern crate` is unnecessary in the new edition
-        //~| HELP use `use`
+        //~^ ERROR unused extern crate
+        //~| HELP remove
+
         extern crate alloc as x;
-        //~^ ERROR `extern crate` is unnecessary in the new edition
-        //~| HELP use `use`
+        //~^ ERROR unused extern crate
+        //~| HELP remove
+
+        pub(in crate::foo::bar) extern crate libc as e;
+        //~^ ERROR `extern crate` is not idiomatic in the new edition
+        //~| HELP convert it to a `pub(in crate::foo::bar) use`
+
+        fn dummy() {
+            unsafe {
+                e::getpid();
+            }
+        }
+    }
+
+    fn dummy() {
+        unsafe {
+            c::getpid();
+            d::getpid();
+        }
     }
 }
 
 
-fn main() {}
+fn main() {
+    unsafe { a::getpid(); }
+    unsafe { b::getpid(); }
+}
diff --git a/src/test/ui-fulldeps/unnecessary-extern-crate.stderr b/src/test/ui-fulldeps/unnecessary-extern-crate.stderr
index b9ccf5b19e0..a4307112157 100644
--- a/src/test/ui-fulldeps/unnecessary-extern-crate.stderr
+++ b/src/test/ui-fulldeps/unnecessary-extern-crate.stderr
@@ -1,4 +1,4 @@
-error: `extern crate` is unnecessary in the new edition
+error: unused extern crate
   --> $DIR/unnecessary-extern-crate.rs:16:1
    |
 LL | extern crate alloc;
@@ -7,62 +7,92 @@ LL | extern crate alloc;
 note: lint level defined here
   --> $DIR/unnecessary-extern-crate.rs:13:9
    |
-LL | #![deny(unnecessary_extern_crates)]
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^
+LL | #![deny(unused_extern_crates)]
+   |         ^^^^^^^^^^^^^^^^^^^^
 
-error: `extern crate` is unnecessary in the new edition
+error: unused extern crate
   --> $DIR/unnecessary-extern-crate.rs:19:1
    |
 LL | extern crate alloc as x;
-   | ^^^^^^^^^^^^^^^^^^^^^^^^ help: use `use`: `use alloc as x;`
+   | ^^^^^^^^^^^^^^^^^^^^^^^^ help: remove it
 
-error: `extern crate` is unnecessary in the new edition
-  --> $DIR/unnecessary-extern-crate.rs:25:1
+error: `extern crate` is not idiomatic in the new edition
+  --> $DIR/unnecessary-extern-crate.rs:26:1
    |
 LL | pub extern crate test as y;
-   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: use `pub use`: `pub use test as y;`
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: convert it to a `pub use`
 
-error: `extern crate` is unnecessary in the new edition
-  --> $DIR/unnecessary-extern-crate.rs:28:1
+error: `extern crate` is not idiomatic in the new edition
+  --> $DIR/unnecessary-extern-crate.rs:30:1
    |
 LL | pub extern crate libc;
-   | ^^^^^^^^^^^^^^^^^^^^^^ help: use `pub use`: `pub use libc;`
+   | ^^^^^^^^^^^^^^^^^^^^^^ help: convert it to a `pub use`
 
-error: `extern crate` is unnecessary in the new edition
-  --> $DIR/unnecessary-extern-crate.rs:34:5
+error: `extern crate` is not idiomatic in the new edition
+  --> $DIR/unnecessary-extern-crate.rs:34:1
+   |
+LL | pub(crate) extern crate libc as a;
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: convert it to a `pub(crate) use`
+
+error: `extern crate` is not idiomatic in the new edition
+  --> $DIR/unnecessary-extern-crate.rs:38:1
+   |
+LL | crate extern crate libc as b;
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: convert it to a `crate use`
+
+error: `extern crate` is not idiomatic in the new edition
+  --> $DIR/unnecessary-extern-crate.rs:43:5
+   |
+LL |     pub(in crate::foo) extern crate libc as c;
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: convert it to a `pub(in crate::foo) use`
+
+error: `extern crate` is not idiomatic in the new edition
+  --> $DIR/unnecessary-extern-crate.rs:47:5
+   |
+LL |     pub(super) extern crate libc as d;
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: convert it to a `pub(super) use`
+
+error: unused extern crate
+  --> $DIR/unnecessary-extern-crate.rs:51:5
    |
 LL |     extern crate alloc;
-   |     ^^^^^^^^^^^^^^^^^^^ help: use `use`: `use alloc;`
+   |     ^^^^^^^^^^^^^^^^^^^ help: remove it
 
-error: `extern crate` is unnecessary in the new edition
-  --> $DIR/unnecessary-extern-crate.rs:37:5
+error: unused extern crate
+  --> $DIR/unnecessary-extern-crate.rs:55:5
    |
 LL |     extern crate alloc as x;
-   |     ^^^^^^^^^^^^^^^^^^^^^^^^ help: use `use`: `use alloc as x;`
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^ help: remove it
 
-error: `extern crate` is unnecessary in the new edition
-  --> $DIR/unnecessary-extern-crate.rs:40:5
+error: `extern crate` is not idiomatic in the new edition
+  --> $DIR/unnecessary-extern-crate.rs:59:5
    |
 LL |     pub extern crate test;
-   |     ^^^^^^^^^^^^^^^^^^^^^^ help: use `pub use`: `pub use test;`
+   |     ^^^^^^^^^^^^^^^^^^^^^^ help: convert it to a `pub use`
 
-error: `extern crate` is unnecessary in the new edition
-  --> $DIR/unnecessary-extern-crate.rs:43:5
+error: `extern crate` is not idiomatic in the new edition
+  --> $DIR/unnecessary-extern-crate.rs:63:5
    |
 LL |     pub extern crate test as y;
-   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: use `pub use`: `pub use test as y;`
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: convert it to a `pub use`
 
-error: `extern crate` is unnecessary in the new edition
-  --> $DIR/unnecessary-extern-crate.rs:47:9
+error: unused extern crate
+  --> $DIR/unnecessary-extern-crate.rs:68:9
    |
 LL |         extern crate alloc;
-   |         ^^^^^^^^^^^^^^^^^^^ help: use `use`: `use alloc;`
+   |         ^^^^^^^^^^^^^^^^^^^ help: remove it
 
-error: `extern crate` is unnecessary in the new edition
-  --> $DIR/unnecessary-extern-crate.rs:50:9
+error: unused extern crate
+  --> $DIR/unnecessary-extern-crate.rs:72:9
    |
 LL |         extern crate alloc as x;
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^ help: use `use`: `use alloc as x;`
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^ help: remove it
+
+error: `extern crate` is not idiomatic in the new edition
+  --> $DIR/unnecessary-extern-crate.rs:76:9
+   |
+LL |         pub(in crate::foo::bar) extern crate libc as e;
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: convert it to a `pub(in crate::foo::bar) use`
 
-error: aborting due to 10 previous errors
+error: aborting due to 15 previous errors
 
diff --git a/src/test/ui/borrowck/promote-ref-mut-in-let-issue-46557.nll.stderr b/src/test/ui/borrowck/promote-ref-mut-in-let-issue-46557.nll.stderr
new file mode 100644
index 00000000000..95acdab3e80
--- /dev/null
+++ b/src/test/ui/borrowck/promote-ref-mut-in-let-issue-46557.nll.stderr
@@ -0,0 +1,63 @@
+error[E0597]: borrowed value does not live long enough
+  --> $DIR/promote-ref-mut-in-let-issue-46557.rs:15:21
+   |
+LL |   fn gimme_static_mut_let() -> &'static mut u32 {
+   |  _______________________________________________-
+LL | |     let ref mut x = 1234543; //~ ERROR
+   | |                     ^^^^^^^ temporary value does not live long enough
+LL | |     x
+LL | | }
+   | | -
+   | | |
+   | |_temporary value only lives until here
+   |   borrow later used here
+
+error[E0597]: borrowed value does not live long enough
+  --> $DIR/promote-ref-mut-in-let-issue-46557.rs:20:25
+   |
+LL |   fn gimme_static_mut_let_nested() -> &'static mut u32 {
+   |  ______________________________________________________-
+LL | |     let (ref mut x, ) = (1234543, ); //~ ERROR
+   | |                         ^^^^^^^^^^^ temporary value does not live long enough
+LL | |     x
+LL | | }
+   | | -
+   | | |
+   | |_temporary value only lives until here
+   |   borrow later used here
+
+error[E0597]: borrowed value does not live long enough
+  --> $DIR/promote-ref-mut-in-let-issue-46557.rs:25:11
+   |
+LL |     match 1234543 {
+   |           ^^^^^^^ temporary value does not live long enough
+...
+LL | }
+   | - temporary value only lives until here
+   |
+   = note: borrowed value must be valid for the static lifetime...
+
+error[E0597]: borrowed value does not live long enough
+  --> $DIR/promote-ref-mut-in-let-issue-46557.rs:31:11
+   |
+LL |     match (123443,) {
+   |           ^^^^^^^^^ temporary value does not live long enough
+...
+LL | }
+   | - temporary value only lives until here
+   |
+   = note: borrowed value must be valid for the static lifetime...
+
+error[E0597]: borrowed value does not live long enough
+  --> $DIR/promote-ref-mut-in-let-issue-46557.rs:37:10
+   |
+LL |     &mut 1234543 //~ ERROR
+   |          ^^^^^^^ temporary value does not live long enough
+LL | }
+   | - temporary value only lives until here
+   |
+   = note: borrowed value must be valid for the static lifetime...
+
+error: aborting due to 5 previous errors
+
+For more information about this error, try `rustc --explain E0597`.
diff --git a/src/test/ui/borrowck/promote-ref-mut-in-let-issue-46557.rs b/src/test/ui/borrowck/promote-ref-mut-in-let-issue-46557.rs
new file mode 100644
index 00000000000..4c5f458d6a3
--- /dev/null
+++ b/src/test/ui/borrowck/promote-ref-mut-in-let-issue-46557.rs
@@ -0,0 +1,41 @@
+// Copyright 2014 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+// Test that we fail to promote the constant here which has a `ref
+// mut` borrow.
+
+fn gimme_static_mut_let() -> &'static mut u32 {
+    let ref mut x = 1234543; //~ ERROR
+    x
+}
+
+fn gimme_static_mut_let_nested() -> &'static mut u32 {
+    let (ref mut x, ) = (1234543, ); //~ ERROR
+    x
+}
+
+fn gimme_static_mut_match() -> &'static mut u32 {
+    match 1234543 {
+        ref mut x => x //~ ERROR
+    }
+}
+
+fn gimme_static_mut_match_nested() -> &'static mut u32 {
+    match (123443,) {
+        (ref mut x,) => x, //~ ERROR
+    }
+}
+
+fn gimme_static_mut_ampersand() -> &'static mut u32 {
+    &mut 1234543 //~ ERROR
+}
+
+fn main() {
+}
diff --git a/src/test/ui/borrowck/promote-ref-mut-in-let-issue-46557.stderr b/src/test/ui/borrowck/promote-ref-mut-in-let-issue-46557.stderr
new file mode 100644
index 00000000000..931eb7da744
--- /dev/null
+++ b/src/test/ui/borrowck/promote-ref-mut-in-let-issue-46557.stderr
@@ -0,0 +1,57 @@
+error[E0597]: borrowed value does not live long enough
+  --> $DIR/promote-ref-mut-in-let-issue-46557.rs:15:9
+   |
+LL |     let ref mut x = 1234543; //~ ERROR
+   |         ^^^^^^^^^ temporary value does not live long enough
+LL |     x
+LL | }
+   | - temporary value only lives until here
+   |
+   = note: borrowed value must be valid for the static lifetime...
+
+error[E0597]: borrowed value does not live long enough
+  --> $DIR/promote-ref-mut-in-let-issue-46557.rs:20:10
+   |
+LL |     let (ref mut x, ) = (1234543, ); //~ ERROR
+   |          ^^^^^^^^^ borrowed value does not live long enough
+LL |     x
+LL | }
+   | - borrowed value only lives until here
+   |
+   = note: borrowed value must be valid for the static lifetime...
+
+error[E0597]: borrowed value does not live long enough
+  --> $DIR/promote-ref-mut-in-let-issue-46557.rs:26:9
+   |
+LL |         ref mut x => x //~ ERROR
+   |         ^^^^^^^^^ temporary value does not live long enough
+LL |     }
+LL | }
+   | - temporary value only lives until here
+   |
+   = note: borrowed value must be valid for the static lifetime...
+
+error[E0597]: borrowed value does not live long enough
+  --> $DIR/promote-ref-mut-in-let-issue-46557.rs:32:10
+   |
+LL |         (ref mut x,) => x, //~ ERROR
+   |          ^^^^^^^^^ borrowed value does not live long enough
+LL |     }
+LL | }
+   | - borrowed value only lives until here
+   |
+   = note: borrowed value must be valid for the static lifetime...
+
+error[E0597]: borrowed value does not live long enough
+  --> $DIR/promote-ref-mut-in-let-issue-46557.rs:37:10
+   |
+LL |     &mut 1234543 //~ ERROR
+   |          ^^^^^^^ temporary value does not live long enough
+LL | }
+   | - temporary value only lives until here
+   |
+   = note: borrowed value must be valid for the static lifetime...
+
+error: aborting due to 5 previous errors
+
+For more information about this error, try `rustc --explain E0597`.
diff --git a/src/test/ui/deriving-with-repr-packed.rs b/src/test/ui/deriving-with-repr-packed.rs
index 0c52829799e..43375098cb5 100644
--- a/src/test/ui/deriving-with-repr-packed.rs
+++ b/src/test/ui/deriving-with-repr-packed.rs
@@ -33,7 +33,7 @@ pub struct Bar(u32, u32, u32);
 struct Y(usize);
 
 #[derive(PartialEq)]
-//~^ ERROR #[derive] can't be used on a non-Copy #[repr(packed)]
+//~^ ERROR #[derive] can't be used
 //~| hard error
 #[repr(packed)]
 struct X(Y);
diff --git a/src/test/ui/deriving-with-repr-packed.stderr b/src/test/ui/deriving-with-repr-packed.stderr
index 64aefbcd5df..a7599c1e7db 100644
--- a/src/test/ui/deriving-with-repr-packed.stderr
+++ b/src/test/ui/deriving-with-repr-packed.stderr
@@ -21,7 +21,7 @@ LL | #[derive(Copy, Clone, PartialEq, Eq)]
    = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
    = note: for more information, see issue #46043 <https://github.com/rust-lang/rust/issues/46043>
 
-error: #[derive] can't be used on a non-Copy #[repr(packed)] struct (error E0133)
+error: #[derive] can't be used on a #[repr(packed)] struct that does not derive Copy (error E0133)
   --> $DIR/deriving-with-repr-packed.rs:26:10
    |
 LL | #[derive(PartialEq, Eq)]
@@ -30,7 +30,7 @@ LL | #[derive(PartialEq, Eq)]
    = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
    = note: for more information, see issue #46043 <https://github.com/rust-lang/rust/issues/46043>
 
-error: #[derive] can't be used on a non-Copy #[repr(packed)] struct (error E0133)
+error: #[derive] can't be used on a #[repr(packed)] struct that does not derive Copy (error E0133)
   --> $DIR/deriving-with-repr-packed.rs:35:10
    |
 LL | #[derive(PartialEq)]
diff --git a/src/test/ui/error-codes/E0152.rs b/src/test/ui/error-codes/E0152.rs
index ae501b94e3f..8fbad7b3ff3 100644
--- a/src/test/ui/error-codes/E0152.rs
+++ b/src/test/ui/error-codes/E0152.rs
@@ -10,7 +10,7 @@
 
 #![feature(lang_items)]
 
-#[lang = "panic_fmt"]
+#[lang = "panic_impl"]
 struct Foo; //~ ERROR E0152
 
 fn main() {
diff --git a/src/test/ui/error-codes/E0152.stderr b/src/test/ui/error-codes/E0152.stderr
index f67022bd6d3..c7f5f362efb 100644
--- a/src/test/ui/error-codes/E0152.stderr
+++ b/src/test/ui/error-codes/E0152.stderr
@@ -1,4 +1,4 @@
-error[E0152]: duplicate lang item found: `panic_fmt`.
+error[E0152]: duplicate lang item found: `panic_impl`.
   --> $DIR/E0152.rs:14:1
    |
 LL | struct Foo; //~ ERROR E0152
diff --git a/src/test/ui/issue-23217.stderr b/src/test/ui/issue-23217.stderr
index d542a10e9b6..d87f239bca6 100644
--- a/src/test/ui/issue-23217.stderr
+++ b/src/test/ui/issue-23217.stderr
@@ -6,7 +6,7 @@ LL | pub enum SomeEnum {
 LL |     B = SomeEnum::A,
    |         ^^^^^^^^^^^ variant not found in `SomeEnum`
    |
-   = note: did you mean `variant::B`?
+   = note: did you mean `SomeEnum::B`?
 
 error: aborting due to previous error
 
diff --git a/src/test/ui/issue-28971.stderr b/src/test/ui/issue-28971.stderr
index df114351ff5..c04e21f7c58 100644
--- a/src/test/ui/issue-28971.stderr
+++ b/src/test/ui/issue-28971.stderr
@@ -7,7 +7,7 @@ LL | enum Foo {
 LL |             Foo::Baz(..) => (),
    |             ^^^^^^^^^^^^ variant not found in `Foo`
    |
-   = note: did you mean `variant::Bar`?
+   = note: did you mean `Foo::Bar`?
 
 error: aborting due to previous error
 
diff --git a/src/test/ui/rfc-2166-underscore-imports/basic.stderr b/src/test/ui/rfc-2166-underscore-imports/basic.stderr
index 4530d0fa604..c12c74b50e2 100644
--- a/src/test/ui/rfc-2166-underscore-imports/basic.stderr
+++ b/src/test/ui/rfc-2166-underscore-imports/basic.stderr
@@ -20,7 +20,7 @@ warning: unused extern crate
   --> $DIR/basic.rs:33:5
    |
 LL |     extern crate core as _; //~ WARN unused extern crate
-   |     ^^^^^^^^^^^^^^^^^^^^^^^
+   |     ^^^^^^^^^^^^^^^^^^^^^^^ help: remove it
    |
 note: lint level defined here
   --> $DIR/basic.rs:14:25
diff --git a/src/test/ui/rust-2018/extern-crate-idiomatic-in-2018.fixed b/src/test/ui/rust-2018/extern-crate-idiomatic-in-2018.fixed
new file mode 100644
index 00000000000..4f99c1240f8
--- /dev/null
+++ b/src/test/ui/rust-2018/extern-crate-idiomatic-in-2018.fixed
@@ -0,0 +1,36 @@
+// Copyright 2018 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+// aux-build:edition-lint-paths.rs
+// run-rustfix
+// compile-flags:--edition 2018
+
+// The "normal case". Ideally we would remove the `extern crate` here,
+// but we don't.
+
+#![feature(rust_2018_preview)]
+#![deny(rust_2018_idioms)]
+#![allow(dead_code)]
+
+
+//~^ ERROR unused extern crate
+
+use edition_lint_paths as bar;
+//~^ ERROR `extern crate` is not idiomatic in the new edition
+
+fn main() {
+    // This is not considered to *use* the `extern crate` in Rust 2018:
+    use edition_lint_paths::foo;
+    foo();
+
+    // But this should be a use of the (renamed) crate:
+    crate::bar::foo();
+}
+
diff --git a/src/test/ui/rust-2018/extern-crate-idiomatic-in-2018.rs b/src/test/ui/rust-2018/extern-crate-idiomatic-in-2018.rs
new file mode 100644
index 00000000000..9c1235a2967
--- /dev/null
+++ b/src/test/ui/rust-2018/extern-crate-idiomatic-in-2018.rs
@@ -0,0 +1,36 @@
+// Copyright 2018 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+// aux-build:edition-lint-paths.rs
+// run-rustfix
+// compile-flags:--edition 2018
+
+// The "normal case". Ideally we would remove the `extern crate` here,
+// but we don't.
+
+#![feature(rust_2018_preview)]
+#![deny(rust_2018_idioms)]
+#![allow(dead_code)]
+
+extern crate edition_lint_paths;
+//~^ ERROR unused extern crate
+
+extern crate edition_lint_paths as bar;
+//~^ ERROR `extern crate` is not idiomatic in the new edition
+
+fn main() {
+    // This is not considered to *use* the `extern crate` in Rust 2018:
+    use edition_lint_paths::foo;
+    foo();
+
+    // But this should be a use of the (renamed) crate:
+    crate::bar::foo();
+}
+
diff --git a/src/test/ui/rust-2018/extern-crate-idiomatic-in-2018.stderr b/src/test/ui/rust-2018/extern-crate-idiomatic-in-2018.stderr
new file mode 100644
index 00000000000..b3afa2bd1d5
--- /dev/null
+++ b/src/test/ui/rust-2018/extern-crate-idiomatic-in-2018.stderr
@@ -0,0 +1,21 @@
+error: unused extern crate
+  --> $DIR/extern-crate-idiomatic-in-2018.rs:22:1
+   |
+LL | extern crate edition_lint_paths;
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: remove it
+   |
+note: lint level defined here
+  --> $DIR/extern-crate-idiomatic-in-2018.rs:19:9
+   |
+LL | #![deny(rust_2018_idioms)]
+   |         ^^^^^^^^^^^^^^^^
+   = note: #[deny(unused_extern_crates)] implied by #[deny(rust_2018_idioms)]
+
+error: `extern crate` is not idiomatic in the new edition
+  --> $DIR/extern-crate-idiomatic-in-2018.rs:25:1
+   |
+LL | extern crate edition_lint_paths as bar;
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: convert it to a `use`
+
+error: aborting due to 2 previous errors
+
diff --git a/src/test/ui/suggestions/removing-extern-crate.fixed b/src/test/ui/suggestions/removing-extern-crate.fixed
index 723137f5db0..83b35cec809 100644
--- a/src/test/ui/suggestions/removing-extern-crate.fixed
+++ b/src/test/ui/suggestions/removing-extern-crate.fixed
@@ -16,12 +16,12 @@
 #![warn(rust_2018_idioms)]
 #![allow(unused_imports)]
 
-use std as foo;
+
 
 
 mod another {
-    use std as foo;
-    use std;
+    
+    
 }
 
 fn main() {}
diff --git a/src/test/ui/suggestions/removing-extern-crate.stderr b/src/test/ui/suggestions/removing-extern-crate.stderr
index 39d22de0277..f2eed27a266 100644
--- a/src/test/ui/suggestions/removing-extern-crate.stderr
+++ b/src/test/ui/suggestions/removing-extern-crate.stderr
@@ -1,31 +1,31 @@
-warning: `extern crate` is unnecessary in the new edition
+warning: unused extern crate
   --> $DIR/removing-extern-crate.rs:19:1
    |
 LL | extern crate std as foo;
-   | ^^^^^^^^^^^^^^^^^^^^^^^^ help: use `use`: `use std as foo;`
+   | ^^^^^^^^^^^^^^^^^^^^^^^^ help: remove it
    |
 note: lint level defined here
   --> $DIR/removing-extern-crate.rs:16:9
    |
 LL | #![warn(rust_2018_idioms)]
    |         ^^^^^^^^^^^^^^^^
-   = note: #[warn(unnecessary_extern_crates)] implied by #[warn(rust_2018_idioms)]
+   = note: #[warn(unused_extern_crates)] implied by #[warn(rust_2018_idioms)]
 
-warning: `extern crate` is unnecessary in the new edition
+warning: unused extern crate
   --> $DIR/removing-extern-crate.rs:20:1
    |
 LL | extern crate core;
    | ^^^^^^^^^^^^^^^^^^ help: remove it
 
-warning: `extern crate` is unnecessary in the new edition
+warning: unused extern crate
   --> $DIR/removing-extern-crate.rs:23:5
    |
 LL |     extern crate std as foo;
-   |     ^^^^^^^^^^^^^^^^^^^^^^^^ help: use `use`: `use std as foo;`
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^ help: remove it
 
-warning: `extern crate` is unnecessary in the new edition
+warning: unused extern crate
   --> $DIR/removing-extern-crate.rs:24:5
    |
 LL |     extern crate std;
-   |     ^^^^^^^^^^^^^^^^^ help: use `use`: `use std;`
+   |     ^^^^^^^^^^^^^^^^^ help: remove it