Auto merge of #55315 - pietroalbini:release-1.30.0, r=Mark-Simulacrum1.30.0

Stable release 1.30

This PR also reverts the stabilization of `non_modrs_mods` and the 2018 edition.

r? @Mark-Simulacrum
cc @rust-lang/release

15 files changed, 244 insertions, 66 deletions

diff --git a/RELEASES.md b/RELEASES.md
index 7ae7dc9935b..70a7dab7227 100644
--- a/RELEASES.md
+++ b/RELEASES.md
@@ -4,34 +4,31 @@ Version 1.30.0 (2018-10-25)
 Language
 --------
 - [Procedural macros are now available.][52081] These kinds of macros allow for
-  more powerful code generation, there is a [new chapter available][proc-macros]
-  in Rust Programming Language book that goes further in depth.
+  more powerful code generation. There is a [new chapter available][proc-macros]
+  in the Rust Programming Language book that goes further in depth.
 - [You can now use keywords as identifiers using the raw identifiers
-  syntax (`r#`).][53236] e.g. `let r#for = true;`
+  syntax (`r#`),][53236] e.g. `let r#for = true;`
 - [Using anonymous parameters in traits is now deprecated with a warning and
   will be a hard error in the 2018 edition.][53272]
 - [You can now use `crate` in paths.][54404] This allows you to refer to the
-  crate root in the path. e.g. `use crate::foo;` refers to `foo` in `src/lib.rs`.
-- [Using a external crate now no longer requires being prefixed with `::`.][54404]
-  e.g. previously using a external crate in a module without a use statement
-  required `let json = ::serde_json::from_str(foo);` can now be written
+  crate root in the path, e.g. `use crate::foo;` refers to `foo` in `src/lib.rs`.
+- [Using a external crate no longer requires being prefixed with `::`.][54404]
+  Previously, using a external crate in a module without a use statement
+  required `let json = ::serde_json::from_str(foo);` but can now be written
   as `let json = serde_json::from_str(foo);`.
 - [You can now apply the `#[used]` attribute to static items to prevent the
-  compiler from optimising them away even if they appear to be unused.][51363]
+  compiler from optimising them away, even if they appear to be unused,][51363]
   e.g. `#[used] static FOO: u32 = 1;`
 - [You can now import and reexport macros from other crates with the `use`
   syntax.][50911] Macros exported with `#[macro_export]` are now placed into
   the root module of the crate. If your macro relies on calling other local
-  macros it is recommended to export with the
-  `#[macro_export(local_inner_macros)]` attribute so that users won't have to
-  import those macros.
-- [`mod.rs` files are now optional.][54146] Previously if you had a `foo` module
-  with a `bar` submodule, you would have `src/foo/mod.rs` and `src/foo/bar.rs`.
-  Now you can have `src/foo.rs` and `src/foo/bar.rs` to achieve the same effect.
+  macros, it is recommended to export with the
+  `#[macro_export(local_inner_macros)]` attribute so users won't have to import
+  those macros.
 - [You can now catch visibility keywords (e.g. `pub`, `pub(crate)`) in macros
   using the `vis` specifier.][53370]
-- [Non-macro attributes now allow all forms of literals not just
-  strings.][53044] e.g. Previously you would write `#[attr("true")]` you can now
+- [Non-macro attributes now allow all forms of literals, not just
+  strings.][53044] Previously, you would write `#[attr("true")]`, and you can now
   write `#[attr(true)]`.
 - [You can now specify a function to handle a panic in the Rust runtime with the
   `#[panic_handler]` attribute.][51366]
@@ -54,9 +51,9 @@ Stabilized APIs
 - [`Ipv6Addr::UNSPECIFIED`]
 - [`Iterator::find_map`]
 
-  The following methods are a replacement methods for `trim_left`, `trim_right`,
-  `trim_left_matches`, and `trim_right_matches`. Which will be deprecated
-  in 1.33.0.
+  The following methods are replacement methods for `trim_left`, `trim_right`,
+  `trim_left_matches`, and `trim_right_matches`, which will be deprecated
+  in 1.33.0:
 - [`str::trim_end_matches`]
 - [`str::trim_end`]
 - [`str::trim_start_matches`]
@@ -76,12 +73,12 @@ Misc
 ----
 - [`rustdoc` allows you to specify what edition to treat your code as with the
   `--edition` option.][54057]
-- [`rustdoc` now has the `--color` (Specify whether to output color) and
-  `--error-format` (Specify error format e.g. `json`) options.][53003]
+- [`rustdoc` now has the `--color` (specify whether to output color) and
+  `--error-format` (specify error format, e.g. `json`) options.][53003]
 - [We now distribute a `rust-gdbgui` script that invokes `gdbgui` with Rust
   debug symbols.][53774]
 - [Attributes from Rust tools such as `rustfmt` or `clippy` are now
-  available.][53459] e.g. `#[rustfmt::skip]` will skip formatting the next item.
+  available,][53459] e.g. `#[rustfmt::skip]` will skip formatting the next item.
 
 [50911]: https://github.com/rust-lang/rust/pull/50911/
 [51363]: https://github.com/rust-lang/rust/pull/51363/
@@ -153,7 +150,7 @@ Compiler
 
 Libraries
 ---------
-- [`Once::call_once` now no longer requires `Once` to be `'static`.][52239]
+- [`Once::call_once` no longer requires `Once` to be `'static`.][52239]
 - [`BuildHasherDefault` now implements `PartialEq` and `Eq`.][52402]
 - [`Box<CStr>`, `Box<OsStr>`, and `Box<Path>` now implement `Clone`.][51912]
 - [Implemented `PartialEq<&str>` for `OsString` and `PartialEq<OsString>`
@@ -169,10 +166,10 @@ Stabilized APIs
 
 Cargo
 -----
-- [Cargo can silently fix some bad lockfiles ][cargo/5831] You can use
-  `--locked` to disable this behaviour.
+- [Cargo can silently fix some bad lockfiles.][cargo/5831] You can use
+  `--locked` to disable this behavior.
 - [`cargo-install` will now allow you to cross compile an install
-  using `--target`][cargo/5614]
+  using `--target`.][cargo/5614]
 - [Added the `cargo-fix` subcommand to automatically move project code from
   2015 edition to 2018.][cargo/5723]
 - [`cargo doc` can now optionally document private types using the
@@ -184,15 +181,15 @@ Misc
   the specified level to that level.][52354] For example `--cap-lints warn`
   will demote `deny` and `forbid` lints to `warn`.
 - [`rustc` and `rustdoc` will now have the exit code of `1` if compilation
-  fails, and `101` if there is a panic.][52197]
+  fails and `101` if there is a panic.][52197]
 - [A preview of clippy has been made available through rustup.][51122]
-  You can install the preview with `rustup component add clippy-preview`
+  You can install the preview with `rustup component add clippy-preview`.
 
 Compatibility Notes
 -------------------
 - [`str::{slice_unchecked, slice_unchecked_mut}` are now deprecated.][51807]
   Use `str::get_unchecked(begin..end)` instead.
-- [`std::env::home_dir` is now deprecated for its unintuitive behaviour.][51656]
+- [`std::env::home_dir` is now deprecated for its unintuitive behavior.][51656]
   Consider using the `home_dir` function from
   https://crates.io/crates/dirs instead.
 - [`rustc` will no longer silently ignore invalid data in target spec.][52330]
@@ -432,7 +429,7 @@ Language
   be used as an identifier.
 - [The dyn syntax is now available.][49968] This syntax is equivalent to the
   bare `Trait` syntax, and should make it clearer when being used in tandem with
-  `impl Trait`. Since it is equivalent to the following syntax:
+  `impl Trait` because it is equivalent to the following syntax:
   `&Trait == &dyn Trait`, `&mut Trait == &mut dyn Trait`, and
   `Box<Trait> == Box<dyn Trait>`.
 - [Attributes on generic parameters such as types and lifetimes are
@@ -495,10 +492,10 @@ Cargo
   a different directory than `target` for placing compilation artifacts.
 - [Cargo will be adding automatic target inference for binaries, benchmarks,
   examples, and tests in the Rust 2018 edition.][cargo/5335] If your project specifies
-  specific targets e.g. using `[[bin]]` and have other binaries in locations
+  specific targets, e.g. using `[[bin]]`, and have other binaries in locations
   where cargo would infer a binary, Cargo will produce a warning. You can
-  disable this feature ahead of time by setting any of the following `autobins`,
-  `autobenches`, `autoexamples`, `autotests` to false.
+  disable this feature ahead of time by setting any of the following to false:
+  `autobins`, `autobenches`, `autoexamples`, `autotests`.
 - [Cargo will now cache compiler information.][cargo/5359] This can be disabled by
   setting `CARGO_CACHE_RUSTC_INFO=0` in your environment.
 
@@ -514,8 +511,8 @@ Compatibility Notes
   work.][49896] e.g. `::core::prelude::v1::StrExt::is_empty("")` will not
   compile, `"".is_empty()` will still compile.
 - [`Debug` output on `atomic::{AtomicBool, AtomicIsize, AtomicPtr, AtomicUsize}`
-  will only print the inner type.][48553] e.g.
-  `print!("{:?}", AtomicBool::new(true))` will print `true`
+  will only print the inner type.][48553] E.g.
+  `print!("{:?}", AtomicBool::new(true))` will print `true`,
   not `AtomicBool(true)`.
 - [The maximum number for `repr(align(N))` is now 2²⁹.][50378] Previously you
   could enter higher numbers but they were not supported by LLVM. Up to 512MB
@@ -578,7 +575,7 @@ Version 1.26.2 (2018-06-05)
 Compatibility Notes
 -------------------
 
-- [The borrow checker was fixed to avoid unsoundness when using match ergonomics][51117]
+- [The borrow checker was fixed to avoid unsoundness when using match ergonomics.][51117]
 
 [51117]: https://github.com/rust-lang/rust/issues/51117
 
@@ -589,18 +586,18 @@ Version 1.26.1 (2018-05-29)
 Tools
 -----
 
-- [RLS now works on Windows][50646]
-- [Rustfmt stopped badly formatting text in some cases][rustfmt/2695]
+- [RLS now works on Windows.][50646]
+- [Rustfmt stopped badly formatting text in some cases.][rustfmt/2695]
 
 
 Compatibility Notes
 --------
 
 - [`fn main() -> impl Trait` no longer works for non-Termination
-  trait][50656]
+  trait.][50656]
   This reverts an accidental stabilization.
-- [`NaN > NaN` no longer returns true in const-fn contexts][50812]
-- [Prohibit using turbofish for `impl Trait` in method arguments][50950]
+- [`NaN > NaN` no longer returns true in const-fn contexts.][50812]
+- [Prohibit using turbofish for `impl Trait` in method arguments.][50950]
 
 [50646]: https://github.com/rust-lang/rust/issues/50646
 [50656]: https://github.com/rust-lang/rust/pull/50656
@@ -616,18 +613,18 @@ Language
 - [Closures now implement `Copy` and/or `Clone` if all captured variables
   implement either or both traits.][49299]
 - [The inclusive range syntax e.g. `for x in 0..=10` is now stable.][47813]
-- [The `'_` lifetime is now stable. The underscore lifetime can be used anywhere where a
+- [The `'_` lifetime is now stable. The underscore lifetime can be used anywhere a
   lifetime can be elided.][49458]
 - [`impl Trait` is now stable allowing you to have abstract types in returns
-   or in function parameters.][49255] e.g. `fn foo() -> impl Iterator<Item=u8>` or
+   or in function parameters.][49255] E.g. `fn foo() -> impl Iterator<Item=u8>` or
   `fn open(path: impl AsRef<Path>)`.
 - [Pattern matching will now automatically apply dereferences.][49394]
 - [128-bit integers in the form of `u128` and `i128` are now stable.][49101]
 - [`main` can now return `Result<(), E: Debug>`][49162] in addition to `()`.
 - [A lot of operations are now available in a const context.][46882] E.g. You
   can now index into constant arrays, reference and dereference into constants,
-  and use Tuple struct constructors.
-- [Fixed entry slice patterns are now stable.][48516] e.g.
+  and use tuple struct constructors.
+- [Fixed entry slice patterns are now stable.][48516] E.g.
   ```rust
   let points = [1, 2, 3, 4];
   match points {
@@ -1052,7 +1049,7 @@ Language
 Compiler
 --------
 - [Enabled `TrapUnreachable` in LLVM which should mitigate the impact of
-  undefined behaviour.][45920]
+  undefined behavior.][45920]
 - [rustc now suggests renaming import if names clash.][45660]
 - [Display errors/warnings correctly when there are zero-width or
   wide characters.][45711]
diff --git a/src/ci/run.sh b/src/ci/run.sh
index a965c44031a..7b89ab5a9f8 100755
--- a/src/ci/run.sh
+++ b/src/ci/run.sh
@@ -51,7 +51,7 @@ fi
 #
 # FIXME: need a scheme for changing this `nightly` value to `beta` and `stable`
 #        either automatically or manually.
-export RUST_RELEASE_CHANNEL=beta
+export RUST_RELEASE_CHANNEL=stable
 if [ "$DEPLOY$DEPLOY_ALT" != "" ]; then
   RUST_CONFIGURE_ARGS="$RUST_CONFIGURE_ARGS --release-channel=$RUST_RELEASE_CHANNEL"
   RUST_CONFIGURE_ARGS="$RUST_CONFIGURE_ARGS --enable-llvm-static-stdcpp"
diff --git a/src/doc/rustdoc/src/command-line-arguments.md b/src/doc/rustdoc/src/command-line-arguments.md
index aba485f752a..417608cc5ca 100644
--- a/src/doc/rustdoc/src/command-line-arguments.md
+++ b/src/doc/rustdoc/src/command-line-arguments.md
@@ -345,17 +345,3 @@ $ rustdoc src/lib.rs --sysroot /path/to/sysroot
 
 Similar to `rustc --sysroot`, this lets you change the sysroot `rustdoc` uses
 when compiling your code.
-
-### `--edition`: control the edition of docs and doctests
-
-Using this flag looks like this:
-
-```bash
-$ rustdoc src/lib.rs --edition 2018
-$ rustdoc --test src/lib.rs --edition 2018
-```
-
-This flag allows rustdoc to treat your rust code as the given edition. It will compile doctests with
-the given edition as well. As with `rustc`, the default edition that `rustdoc` will use is `2015`
-(the first edition).
-
diff --git a/src/doc/rustdoc/src/unstable-features.md b/src/doc/rustdoc/src/unstable-features.md
index 071575b1fc0..32fb8c2f7d5 100644
--- a/src/doc/rustdoc/src/unstable-features.md
+++ b/src/doc/rustdoc/src/unstable-features.md
@@ -346,6 +346,19 @@ details.
 
 [issue-display-warnings]: https://github.com/rust-lang/rust/issues/41574
 
+### `--edition`: control the edition of docs and doctests
+
+Using this flag looks like this:
+
+```bash
+$ rustdoc src/lib.rs -Z unstable-options --edition 2018
+$ rustdoc --test src/lib.rs -Z unstable-options --edition 2018
+```
+
+This flag allows rustdoc to treat your rust code as the given edition. It will compile doctests with
+the given edition as well. As with `rustc`, the default edition that `rustdoc` will use is `2015`
+(the first edition).
+
 ### `--extern-html-root-url`: control how rustdoc links to non-local crates
 
 Using this flag looks like this:
diff --git a/src/librustdoc/lib.rs b/src/librustdoc/lib.rs
index e9fac23b767..3a70c55e173 100644
--- a/src/librustdoc/lib.rs
+++ b/src/librustdoc/lib.rs
@@ -286,7 +286,7 @@ fn opts() -> Vec<RustcOptGroup> {
                       \"light-suffix.css\"",
                      "PATH")
         }),
-        stable("edition", |o| {
+        unstable("edition", |o| {
             o.optopt("", "edition",
                      "edition to use when compiling rust code (default: 2015)",
                      "EDITION")
diff --git a/src/libsyntax/feature_gate.rs b/src/libsyntax/feature_gate.rs
index 1d9a278a55b..26067304f92 100644
--- a/src/libsyntax/feature_gate.rs
+++ b/src/libsyntax/feature_gate.rs
@@ -37,7 +37,7 @@ use visit::{self, FnKind, Visitor};
 use parse::ParseSess;
 use symbol::{keywords, Symbol};
 
-use std::{env};
+use std::{env, path};
 
 macro_rules! set {
     // The const_fn feature also enables the min_const_fn feature, because `min_const_fn` allows
@@ -403,6 +403,9 @@ declare_features! (
     // `extern` in paths
     (active, extern_in_paths, "1.23.0", Some(44660), None),
 
+    // `foo.rs` as an alternative to `foo/mod.rs`
+    (active, non_modrs_mods, "1.24.0", Some(44660), Some(Edition::Edition2018)),
+
     // Use `?` as the Kleene "at most one" operator
     (active, macro_at_most_once_rep, "1.25.0", Some(48075), None),
 
@@ -651,8 +654,6 @@ declare_features! (
     (accepted, repr_transparent, "1.28.0", Some(43036), None),
     // Defining procedural macros in `proc-macro` crates
     (accepted, proc_macro, "1.29.0", Some(38356), None),
-    // `foo.rs` as an alternative to `foo/mod.rs`
-    (accepted, non_modrs_mods, "1.30.0", Some(44660), None),
     // Allows use of the :vis macro fragment specifier
     (accepted, macro_vis_matcher, "1.30.0", Some(41022), None),
     // Allows importing and reexporting macros with `use`,
@@ -1500,6 +1501,31 @@ impl<'a> PostExpansionVisitor<'a> {
     }
 }
 
+impl<'a> PostExpansionVisitor<'a> {
+    fn whole_crate_feature_gates(&mut self, _krate: &ast::Crate) {
+        for &(ident, span) in &*self.context.parse_sess.non_modrs_mods.borrow() {
+            if !span.allows_unstable() {
+                let cx = &self.context;
+                let level = GateStrength::Hard;
+                let has_feature = cx.features.non_modrs_mods;
+                let name = "non_modrs_mods";
+                debug!("gate_feature(feature = {:?}, span = {:?}); has? {}",
+                        name, span, has_feature);
+
+                if !has_feature && !span.allows_unstable() {
+                    leveled_feature_err(
+                        cx.parse_sess, name, span, GateIssue::Language,
+                        "mod statements in non-mod.rs files are unstable", level
+                    )
+                    .help(&format!("on stable builds, rename this file to {}{}mod.rs",
+                                   ident, path::MAIN_SEPARATOR))
+                    .emit();
+                }
+            }
+        }
+    }
+}
+
 impl<'a> Visitor<'a> for PostExpansionVisitor<'a> {
     fn visit_attribute(&mut self, attr: &ast::Attribute) {
         if !attr.span.allows_unstable() {
@@ -2066,6 +2092,7 @@ pub fn check_crate(krate: &ast::Crate,
     };
 
     let visitor = &mut PostExpansionVisitor { context: &ctx };
+    visitor.whole_crate_feature_gates(krate);
     visit::walk_crate(visitor, krate);
 }
 
diff --git a/src/libsyntax_pos/edition.rs b/src/libsyntax_pos/edition.rs
index 7709db72a02..fce8fc3db4e 100644
--- a/src/libsyntax_pos/edition.rs
+++ b/src/libsyntax_pos/edition.rs
@@ -65,7 +65,7 @@ impl Edition {
     pub fn is_stable(&self) -> bool {
         match *self {
             Edition::Edition2015 => true,
-            Edition::Edition2018 => true,
+            Edition::Edition2018 => false,
         }
     }
 }
diff --git a/src/test/ui/directory_ownership/mod_file_not_owning.rs b/src/test/ui/directory_ownership/mod_file_not_owning.rs
new file mode 100644
index 00000000000..ff93fddf9b3
--- /dev/null
+++ b/src/test/ui/directory_ownership/mod_file_not_owning.rs
@@ -0,0 +1,15 @@
+// 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.
+
+// error-pattern: mod statements in non-mod.rs files are unstable
+
+mod mod_file_not_owning_aux1;
+
+fn main() {}
diff --git a/src/test/ui/directory_ownership/mod_file_not_owning.stderr b/src/test/ui/directory_ownership/mod_file_not_owning.stderr
new file mode 100644
index 00000000000..e2937573997
--- /dev/null
+++ b/src/test/ui/directory_ownership/mod_file_not_owning.stderr
@@ -0,0 +1,15 @@
+error[E0658]: mod statements in non-mod.rs files are unstable (see issue #44660)
+  --> $DIR/mod_file_not_owning_aux1.rs:14:17
+   |
+LL |     () => { mod mod_file_not_owning_aux2; }
+   |                 ^^^^^^^^^^^^^^^^^^^^^^^^
+LL | }
+LL | m!();
+   | ----- in this macro invocation
+   |
+   = help: add #![feature(non_modrs_mods)] to the crate attributes to enable
+   = help: on stable builds, rename this file to mod_file_not_owning_aux1/mod.rs
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0658`.
diff --git a/src/test/ui/directory_ownership/unowned_mod_with_path.rs b/src/test/ui/directory_ownership/unowned_mod_with_path.rs
new file mode 100644
index 00000000000..0cffb7cc9e5
--- /dev/null
+++ b/src/test/ui/directory_ownership/unowned_mod_with_path.rs
@@ -0,0 +1,15 @@
+// Copyright 2016 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: mod statements in non-mod.rs files are unstable
+
+// This is not a directory owner since the file name is not "mod.rs".
+#[path = "mod_file_not_owning_aux1.rs"]
+mod foo;
diff --git a/src/test/ui/directory_ownership/unowned_mod_with_path.stderr b/src/test/ui/directory_ownership/unowned_mod_with_path.stderr
new file mode 100644
index 00000000000..0c0b4281434
--- /dev/null
+++ b/src/test/ui/directory_ownership/unowned_mod_with_path.stderr
@@ -0,0 +1,15 @@
+error[E0658]: mod statements in non-mod.rs files are unstable (see issue #44660)
+  --> $DIR/mod_file_not_owning_aux1.rs:14:17
+   |
+LL |     () => { mod mod_file_not_owning_aux2; }
+   |                 ^^^^^^^^^^^^^^^^^^^^^^^^
+LL | }
+LL | m!();
+   | ----- in this macro invocation
+   |
+   = help: add #![feature(non_modrs_mods)] to the crate attributes to enable
+   = help: on stable builds, rename this file to foo/mod.rs
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0658`.
diff --git a/src/test/ui/non_modrs_mods/non_modrs_mods.rs b/src/test/ui/non_modrs_mods/non_modrs_mods.rs
new file mode 100644
index 00000000000..9dc85f4d3f9
--- /dev/null
+++ b/src/test/ui/non_modrs_mods/non_modrs_mods.rs
@@ -0,0 +1,28 @@
+// Copyright 2017 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 the formatting of the feature-gate errors for non_modrs_mods
+//
+// gate-test-non_modrs_mods
+// ignore-windows
+// ignore-pretty issue #37195
+pub mod modrs_mod;
+pub mod foors_mod;
+
+#[path = "some_crazy_attr_mod_dir/arbitrary_name.rs"]
+pub mod attr_mod;
+
+pub fn main() {
+    modrs_mod::inner_modrs_mod::innest::foo();
+    modrs_mod::inner_foors_mod::innest::foo();
+    foors_mod::inner_modrs_mod::innest::foo();
+    foors_mod::inner_foors_mod::innest::foo();
+    attr_mod::inner_modrs_mod::innest::foo();
+}
diff --git a/src/test/ui/non_modrs_mods/non_modrs_mods.stderr b/src/test/ui/non_modrs_mods/non_modrs_mods.stderr
new file mode 100644
index 00000000000..c45ab734fd5
--- /dev/null
+++ b/src/test/ui/non_modrs_mods/non_modrs_mods.stderr
@@ -0,0 +1,39 @@
+error[E0658]: mod statements in non-mod.rs files are unstable (see issue #44660)
+  --> $DIR/modrs_mod/inner_foors_mod.rs:11:9
+   |
+LL | pub mod innest;
+   |         ^^^^^^
+   |
+   = help: add #![feature(non_modrs_mods)] to the crate attributes to enable
+   = help: on stable builds, rename this file to inner_foors_mod/mod.rs
+
+error[E0658]: mod statements in non-mod.rs files are unstable (see issue #44660)
+  --> $DIR/foors_mod.rs:13:9
+   |
+LL | pub mod inner_modrs_mod;
+   |         ^^^^^^^^^^^^^^^
+   |
+   = help: add #![feature(non_modrs_mods)] to the crate attributes to enable
+   = help: on stable builds, rename this file to foors_mod/mod.rs
+
+error[E0658]: mod statements in non-mod.rs files are unstable (see issue #44660)
+  --> $DIR/foors_mod.rs:14:9
+   |
+LL | pub mod inner_foors_mod;
+   |         ^^^^^^^^^^^^^^^
+   |
+   = help: add #![feature(non_modrs_mods)] to the crate attributes to enable
+   = help: on stable builds, rename this file to foors_mod/mod.rs
+
+error[E0658]: mod statements in non-mod.rs files are unstable (see issue #44660)
+  --> $DIR/foors_mod/inner_foors_mod.rs:11:9
+   |
+LL | pub mod innest;
+   |         ^^^^^^
+   |
+   = help: add #![feature(non_modrs_mods)] to the crate attributes to enable
+   = help: on stable builds, rename this file to inner_foors_mod/mod.rs
+
+error: aborting due to 4 previous errors
+
+For more information about this error, try `rustc --explain E0658`.
diff --git a/src/test/ui/run-pass/non_modrs_mods/non_modrs_mods.rs b/src/test/ui/run-pass/non_modrs_mods/non_modrs_mods.rs
new file mode 100644
index 00000000000..a9b240be804
--- /dev/null
+++ b/src/test/ui/run-pass/non_modrs_mods/non_modrs_mods.rs
@@ -0,0 +1,28 @@
+// Copyright 2017 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.
+
+// run-pass
+//
+// ignore-pretty issue #37195
+#![feature(non_modrs_mods)]
+
+pub mod modrs_mod;
+pub mod foors_mod;
+
+#[path = "some_crazy_attr_mod_dir/arbitrary_name.rs"]
+pub mod attr_mod;
+
+pub fn main() {
+    modrs_mod::inner_modrs_mod::innest::foo();
+    modrs_mod::inner_foors_mod::innest::foo();
+    foors_mod::inner_modrs_mod::innest::foo();
+    foors_mod::inner_foors_mod::innest::foo();
+    attr_mod::inner_modrs_mod::innest::foo();
+}
diff --git a/src/tools/cargo b/src/tools/cargo
-Subproject 05e9b01fcd82cbdf3991dabc497f6148baf9d30
+Subproject 36d96825d0f288c6d1bb2219919a277968bd365