From fb98ca716fca8d9342f4cf308622a8e78c072fb7 Mon Sep 17 00:00:00 2001
From: Harald Hoyer <harald@redhat.com>
Date: Thu, 28 Feb 2019 10:25:54 +0100
Subject: [PATCH 01/22] fs::copy() linux: set file mode early

A convenience method like fs::copy() should try to prevent pitfalls a
normal user doesn't think about.

In case of an empty umask, setting the file mode early prevents
temporarily world readable or even writeable files,
because the default mode is 0o666.

In case the target is a named pipe or special device node, setting the
file mode can lead to unwanted side effects, like setting permissons on
`/dev/stdout` or for root setting permissions on `/dev/null`.

copy_file_range() returns EINVAL, if the destination is a FIFO/pipe or
a device like "/dev/null", so fallback to io::copy, too.

Fixes: https://github.com/rust-lang/rust/issues/26933
Fixed: https://github.com/rust-lang/rust/issues/37885
---
 src/libstd/sys/unix/fs.rs | 41 +++++++++++++++++++++++++++------------
 1 file changed, 29 insertions(+), 12 deletions(-)

diff --git a/src/libstd/sys/unix/fs.rs b/src/libstd/sys/unix/fs.rs
index 3b80b475a93db..38052cbde601a 100644
--- a/src/libstd/sys/unix/fs.rs
+++ b/src/libstd/sys/unix/fs.rs
@@ -847,7 +847,8 @@ pub fn copy(from: &Path, to: &Path) -> io::Result<u64> {
 #[cfg(any(target_os = "linux", target_os = "android"))]
 pub fn copy(from: &Path, to: &Path) -> io::Result<u64> {
     use crate::cmp;
-    use crate::fs::File;
+    use crate::fs::{File, OpenOptions};
+    use crate::os::unix::fs::{OpenOptionsExt, PermissionsExt};
     use crate::sync::atomic::{AtomicBool, Ordering};
 
     // Kernel prior to 4.5 don't have copy_file_range
@@ -873,18 +874,35 @@ pub fn copy(from: &Path, to: &Path) -> io::Result<u64> {
         )
     }
 
-    if !from.is_file() {
-        return Err(Error::new(ErrorKind::InvalidInput,
-                              "the source path is not an existing regular file"))
-    }
-
     let mut reader = File::open(from)?;
-    let mut writer = File::create(to)?;
+
     let (perm, len) = {
         let metadata = reader.metadata()?;
-        (metadata.permissions(), metadata.size())
+        if !metadata.is_file() {
+            return Err(Error::new(
+                ErrorKind::InvalidInput,
+                "the source path is not an existing regular file",
+            ));
+        }
+        (metadata.permissions(), metadata.len())
     };
 
+    let mut writer = OpenOptions::new()
+        // create the file with the correct mode right away
+        .mode(perm.mode())
+        .write(true)
+        .create(true)
+        .truncate(true)
+        .open(to)?;
+
+    let writer_metadata = writer.metadata()?;
+    if writer_metadata.is_file() {
+        // Set the correct file permissions, in case the file already existed.
+        // Don't set the permissions on already existing non-files like
+        // pipes/FIFOs or device nodes.
+        writer.set_permissions(perm)?;
+    }
+
     let has_copy_file_range = HAS_COPY_FILE_RANGE.load(Ordering::Relaxed);
     let mut written = 0u64;
     while written < len {
@@ -919,21 +937,20 @@ pub fn copy(from: &Path, to: &Path) -> io::Result<u64> {
                 match err.raw_os_error() {
                     Some(os_err) if os_err == libc::ENOSYS
                                  || os_err == libc::EXDEV
+                                 || os_err == libc::EINVAL
                                  || os_err == libc::EPERM => {
                         // Try fallback io::copy if either:
                         // - Kernel version is < 4.5 (ENOSYS)
                         // - Files are mounted on different fs (EXDEV)
                         // - copy_file_range is disallowed, for example by seccomp (EPERM)
+                        // - copy_file_range cannot be used with pipes or device nodes (EINVAL)
                         assert_eq!(written, 0);
-                        let ret = io::copy(&mut reader, &mut writer)?;
-                        writer.set_permissions(perm)?;
-                        return Ok(ret)
+                        return io::copy(&mut reader, &mut writer);
                     },
                     _ => return Err(err),
                 }
             }
         }
     }
-    writer.set_permissions(perm)?;
     Ok(written)
 }

From 204f087daf6570824832eec56b24d9cd8cbf4a70 Mon Sep 17 00:00:00 2001
From: Igor Matuszewski <Xanewok@gmail.com>
Date: Fri, 1 Mar 2019 10:18:50 +0100
Subject: [PATCH 02/22] librustc_interface: Update scoped-tls to 1.0

Done previously as a part of
https://github.com/rust-lang/rust/pull/58748
---
 Cargo.lock                        | 2 +-
 src/librustc_interface/Cargo.toml | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/Cargo.lock b/Cargo.lock
index 381322bc421d4..2e4fbf02a0e53 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -2774,7 +2774,7 @@ dependencies = [
  "rustc_resolve 0.0.0",
  "rustc_traits 0.0.0",
  "rustc_typeck 0.0.0",
- "scoped-tls 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "scoped-tls 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "serialize 0.0.0",
  "smallvec 0.6.7 (registry+https://github.com/rust-lang/crates.io-index)",
  "syntax 0.0.0",
diff --git a/src/librustc_interface/Cargo.toml b/src/librustc_interface/Cargo.toml
index 1acd3dfc7656a..294e23dc6177c 100644
--- a/src/librustc_interface/Cargo.toml
+++ b/src/librustc_interface/Cargo.toml
@@ -12,7 +12,7 @@ crate-type = ["dylib"]
 log = "0.4"
 rustc-rayon = "0.1.1"
 smallvec = { version = "0.6.7", features = ["union", "may_dangle"] }
-scoped-tls = { version = "0.1.1", features = ["nightly"] }
+scoped-tls = "1.0"
 syntax = { path = "../libsyntax" }
 syntax_ext = { path = "../libsyntax_ext" }
 syntax_pos = { path = "../libsyntax_pos" }

From 196e02192f88fdfdcf131b094882913590d34eb4 Mon Sep 17 00:00:00 2001
From: Guillaume Gomez <guillaume1.gomez@gmail.com>
Date: Fri, 1 Mar 2019 17:03:15 +0100
Subject: [PATCH 03/22] Prevent cache issues on version updates

---
 src/bootstrap/doc.rs | 15 +++++++--------
 1 file changed, 7 insertions(+), 8 deletions(-)

diff --git a/src/bootstrap/doc.rs b/src/bootstrap/doc.rs
index 40f0e5ede8bd7..1891334ac2dd1 100644
--- a/src/bootstrap/doc.rs
+++ b/src/bootstrap/doc.rs
@@ -343,12 +343,10 @@ fn invoke_rustdoc(
         .arg("--html-before-content").arg(&version_info)
         .arg("--html-in-header").arg(&favicon)
         .arg("--markdown-no-toc")
-        .arg("--markdown-playground-url")
-        .arg("https://play.rust-lang.org/")
-        .arg("-o").arg(&out)
-        .arg(&path)
-        .arg("--markdown-css")
-        .arg("../rust.css");
+        .arg("--resource-suffix").arg(crate::channel::CFG_RELEASE_NUM)
+        .arg("--markdown-playground-url").arg("https://play.rust-lang.org/")
+        .arg("-o").arg(&out).arg(&path)
+        .arg("--markdown-css").arg("../rust.css");
 
     builder.run(&mut cmd);
 }
@@ -430,9 +428,9 @@ impl Step for Standalone {
                .arg("--html-before-content").arg(&version_info)
                .arg("--html-in-header").arg(&favicon)
                .arg("--markdown-no-toc")
+               .arg("--resource-suffix").arg(crate::channel::CFG_RELEASE_NUM)
                .arg("--index-page").arg(&builder.src.join("src/doc/index.md"))
-               .arg("--markdown-playground-url")
-               .arg("https://play.rust-lang.org/")
+               .arg("--markdown-playground-url").arg("https://play.rust-lang.org/")
                .arg("-o").arg(&out)
                .arg(&path);
 
@@ -523,6 +521,7 @@ impl Step for Std {
                  .arg("--markdown-css").arg("rust.css")
                  .arg("--markdown-no-toc")
                  .arg("--generate-redirect-pages")
+                 .arg("--resource-suffix").arg(crate::channel::CFG_RELEASE_NUM)
                  .arg("--index-page").arg(&builder.src.join("src/doc/index.md"));
 
             builder.run(&mut cargo);

From c82a42c155aa4b4825cb8dc21e9e498a752af13f Mon Sep 17 00:00:00 2001
From: Edward Barnard <eabarnard@gmail.com>
Date: Sun, 3 Mar 2019 19:47:17 +0000
Subject: [PATCH 04/22] Change `std::fs::copy` to use `copyfile` on MacOS and
 iOS

---
 src/libstd/fs.rs          |  3 +-
 src/libstd/sys/unix/fs.rs | 87 ++++++++++++++++++++++++++++++++++++++-
 2 files changed, 88 insertions(+), 2 deletions(-)

diff --git a/src/libstd/fs.rs b/src/libstd/fs.rs
index 25f2dd73504ae..3454f847ef414 100644
--- a/src/libstd/fs.rs
+++ b/src/libstd/fs.rs
@@ -1581,7 +1581,8 @@ pub fn rename<P: AsRef<Path>, Q: AsRef<Path>>(from: P, to: Q) -> io::Result<()>
 /// `O_CLOEXEC` is set for returned file descriptors.
 /// On Windows, this function currently corresponds to `CopyFileEx`. Alternate
 /// NTFS streams are copied but only the size of the main stream is returned by
-/// this function.
+/// this function. On MacOS, this function corresponds to `copyfile` with
+/// `COPYFILE_ALL`
 /// Note that, this [may change in the future][changes].
 ///
 /// [changes]: ../io/index.html#platform-specific-behavior
diff --git a/src/libstd/sys/unix/fs.rs b/src/libstd/sys/unix/fs.rs
index 3b80b475a93db..7ff098bc9e123 100644
--- a/src/libstd/sys/unix/fs.rs
+++ b/src/libstd/sys/unix/fs.rs
@@ -827,7 +827,10 @@ pub fn canonicalize(p: &Path) -> io::Result<PathBuf> {
     Ok(PathBuf::from(OsString::from_vec(buf)))
 }
 
-#[cfg(not(any(target_os = "linux", target_os = "android")))]
+#[cfg(not(any(target_os = "linux",
+              target_os = "android",
+              target_os = "macos",
+              target_os = "ios")))]
 pub fn copy(from: &Path, to: &Path) -> io::Result<u64> {
     use crate::fs::File;
     if !from.is_file() {
@@ -937,3 +940,85 @@ pub fn copy(from: &Path, to: &Path) -> io::Result<u64> {
     writer.set_permissions(perm)?;
     Ok(written)
 }
+
+#[cfg(any(target_os = "macos", target_os = "ios"))]
+pub fn copy(from: &Path, to: &Path) -> io::Result<u64> {
+    const COPYFILE_ACL: u32 = 1 << 0;
+    const COPYFILE_STAT: u32 = 1 << 1;
+    const COPYFILE_XATTR: u32 = 1 << 2;
+    const COPYFILE_DATA: u32 = 1 << 3;
+
+    const COPYFILE_SECURITY: u32 = COPYFILE_STAT | COPYFILE_ACL;
+    const COPYFILE_METADATA: u32 = COPYFILE_SECURITY | COPYFILE_XATTR;
+    const COPYFILE_ALL: u32 = COPYFILE_METADATA | COPYFILE_DATA;
+
+    const COPYFILE_STATE_COPIED: u32 = 8;
+
+    #[allow(non_camel_case_types)]
+    type copyfile_state_t = *mut libc::c_void;
+    #[allow(non_camel_case_types)]
+    type copyfile_flags_t = u32;
+
+    extern "C" {
+        fn copyfile(
+            from: *const libc::c_char,
+            to: *const libc::c_char,
+            state: copyfile_state_t,
+            flags: copyfile_flags_t,
+        ) -> libc::c_int;
+        fn copyfile_state_alloc() -> copyfile_state_t;
+        fn copyfile_state_free(state: copyfile_state_t) -> libc::c_int;
+        fn copyfile_state_get(
+            state: copyfile_state_t,
+            flag: u32,
+            dst: *mut libc::c_void,
+        ) -> libc::c_int;
+    }
+
+    struct FreeOnDrop(copyfile_state_t);
+    impl Drop for FreeOnDrop {
+        fn drop(&mut self) {
+            // The code below ensures that `FreeOnDrop` is never a null pointer
+            unsafe {
+                // `copyfile_state_free` returns -1 if the `to` or `from` files
+                // cannot be closed. However, this is not considerd this an
+                // error.
+                copyfile_state_free(self.0);
+            }
+        }
+    }
+
+    if !from.is_file() {
+        return Err(Error::new(ErrorKind::InvalidInput,
+                              "the source path is not an existing regular file"))
+    }
+
+    // We ensure that `FreeOnDrop` never contains a null pointer so it is
+    // always safe to call `copyfile_state_free`
+    let state = unsafe {
+        let state = copyfile_state_alloc();
+        if state.is_null() {
+            return Err(crate::io::Error::last_os_error());
+        }
+        FreeOnDrop(state)
+    };
+
+    cvt(unsafe {
+        copyfile(
+            cstr(from)?.as_ptr(),
+            cstr(to)?.as_ptr(),
+            state.0,
+            COPYFILE_ALL,
+        )
+    })?;
+
+    let mut bytes_copied: libc::off_t = 0;
+    cvt(unsafe {
+        copyfile_state_get(
+            state.0,
+            COPYFILE_STATE_COPIED,
+            &mut bytes_copied as *mut libc::off_t as *mut libc::c_void,
+        )
+    })?;
+    Ok(bytes_copied as u64)
+}

From 0a991e424a794d0d556602e88cd2ebf511b05de7 Mon Sep 17 00:00:00 2001
From: Edward Barnard <eabarnard@gmail.com>
Date: Mon, 4 Mar 2019 12:35:46 +0000
Subject: [PATCH 05/22] Add test for the behaviour of `fs::copy` when `to` is a
 symlink

---
 src/libstd/fs.rs | 20 ++++++++++++++++++++
 1 file changed, 20 insertions(+)

diff --git a/src/libstd/fs.rs b/src/libstd/fs.rs
index 3454f847ef414..7b9b5d4de206c 100644
--- a/src/libstd/fs.rs
+++ b/src/libstd/fs.rs
@@ -2837,6 +2837,26 @@ mod tests {
         assert_eq!(check!(out_path.metadata()).len(), copied_len);
     }
 
+    #[test]
+    fn copy_file_follows_dst_symlink() {
+        let tmp = tmpdir();
+        if !got_symlink_permission(&tmp) { return };
+
+        let in_path = tmp.join("in.txt");
+        let out_path = tmp.join("out.txt");
+        let out_path_symlink = tmp.join("out_symlink.txt");
+
+        check!(fs::write(&in_path, "foo"));
+        check!(fs::write(&out_path, "bar"));
+        check!(symlink_file(&out_path, &out_path_symlink));
+
+        check!(fs::copy(&in_path, &out_path_symlink));
+
+        assert!(check!(out_path_symlink.symlink_metadata()).file_type().is_symlink());
+        assert_eq!(check!(fs::read(&out_path_symlink)), b"foo".to_vec());
+        assert_eq!(check!(fs::read(&out_path)), b"foo".to_vec());
+    }
+
     #[test]
     fn symlinks_work() {
         let tmpdir = tmpdir();

From 124ab2a4d87f2d10b88d668e35286af4c00ec12b Mon Sep 17 00:00:00 2001
From: Edward Barnard <eabarnard@gmail.com>
Date: Mon, 4 Mar 2019 12:53:54 +0000
Subject: [PATCH 06/22] Fix typo

---
 src/libstd/fs.rs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/libstd/fs.rs b/src/libstd/fs.rs
index 7b9b5d4de206c..a03f55424a9cd 100644
--- a/src/libstd/fs.rs
+++ b/src/libstd/fs.rs
@@ -1582,7 +1582,7 @@ pub fn rename<P: AsRef<Path>, Q: AsRef<Path>>(from: P, to: Q) -> io::Result<()>
 /// On Windows, this function currently corresponds to `CopyFileEx`. Alternate
 /// NTFS streams are copied but only the size of the main stream is returned by
 /// this function. On MacOS, this function corresponds to `copyfile` with
-/// `COPYFILE_ALL`
+/// `COPYFILE_ALL`.
 /// Note that, this [may change in the future][changes].
 ///
 /// [changes]: ../io/index.html#platform-specific-behavior

From 1243859d402427d90271d646968a6a4e5ad0052b Mon Sep 17 00:00:00 2001
From: Dan Robertson <dan@dlrobertson.com>
Date: Tue, 5 Mar 2019 13:43:48 +0000
Subject: [PATCH 07/22] core: ensure VaList passes improper_ctypes lint

Ensure the core::ffi::VaList structure passes the improper_ctypes lint.
---
 src/libcore/ffi.rs | 14 +++++++-------
 1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/src/libcore/ffi.rs b/src/libcore/ffi.rs
index d88793f2801e7..5cc9c25c21e0f 100644
--- a/src/libcore/ffi.rs
+++ b/src/libcore/ffi.rs
@@ -79,9 +79,9 @@ impl fmt::Debug for VaListImpl {
                      all supported platforms",
            issue = "44930")]
 struct VaListImpl {
-    stack: *mut (),
-    gr_top: *mut (),
-    vr_top: *mut (),
+    stack: *mut c_void,
+    gr_top: *mut c_void,
+    vr_top: *mut c_void,
     gr_offs: i32,
     vr_offs: i32,
 }
@@ -98,8 +98,8 @@ struct VaListImpl {
     gpr: u8,
     fpr: u8,
     reserved: u16,
-    overflow_arg_area: *mut (),
-    reg_save_area: *mut (),
+    overflow_arg_area: *mut c_void,
+    reg_save_area: *mut c_void,
 }
 
 /// x86_64 ABI implementation of a `va_list`.
@@ -113,8 +113,8 @@ struct VaListImpl {
 struct VaListImpl {
     gp_offset: i32,
     fp_offset: i32,
-    overflow_arg_area: *mut (),
-    reg_save_area: *mut (),
+    overflow_arg_area: *mut c_void,
+    reg_save_area: *mut c_void,
 }
 
 /// A wrapper for a `va_list`

From 72958acd57fb32e0f8027c0d7e76c9a0c7f155d2 Mon Sep 17 00:00:00 2001
From: Alex Crichton <alex@alexcrichton.com>
Date: Fri, 1 Mar 2019 11:47:06 -0800
Subject: [PATCH 08/22] std: Spin for a global malloc lock on wasm32

There's lots of comments in the code, but the main gist of this commit
is that the acquisition of the global malloc lock on the
`wasm32-unknown-unknown` target when threads are enabled will not spin
on contention rather than block.
---
 src/libstd/sys/wasm/alloc.rs | 95 ++++++++++++++++++++++++++++++------
 1 file changed, 80 insertions(+), 15 deletions(-)

diff --git a/src/libstd/sys/wasm/alloc.rs b/src/libstd/sys/wasm/alloc.rs
index b9098548b9c1e..c1af6ec12623c 100644
--- a/src/libstd/sys/wasm/alloc.rs
+++ b/src/libstd/sys/wasm/alloc.rs
@@ -49,7 +49,6 @@ unsafe impl GlobalAlloc for System {
 
 #[cfg(target_feature = "atomics")]
 mod lock {
-    use crate::arch::wasm32;
     use crate::sync::atomic::{AtomicI32, Ordering::SeqCst};
 
     static LOCKED: AtomicI32 = AtomicI32::new(0);
@@ -61,14 +60,76 @@ mod lock {
             if LOCKED.swap(1, SeqCst) == 0 {
                 return DropLock
             }
-            unsafe {
-                let r = wasm32::i32_atomic_wait(
-                    &LOCKED as *const AtomicI32 as *mut i32,
-                    1,  // expected value
-                    -1, // timeout
-                );
-                debug_assert!(r == 0 || r == 1);
-            }
+            // Ok so here's where things get a little depressing. At this point
+            // in time we need to synchronously acquire a lock, but we're
+            // contending with some other thread. Typically we'd execute some
+            // form of `i32.atomic.wait` like so:
+            //
+            //     unsafe {
+            //         let r = core::arch::wasm32::i32_atomic_wait(
+            //             &LOCKED as *const AtomicI32 as *mut i32,
+            //             1,  //     expected value
+            //             -1, //     timeout
+            //         );
+            //         debug_assert!(r == 0 || r == 1);
+            //     }
+            //
+            // Unfortunately though in doing so we would cause issues for the
+            // main thread. The main thread in a web browser *cannot ever
+            // block*, no exceptions. This means that the main thread can't
+            // actually execute the `i32.atomic.wait` instruction.
+            //
+            // As a result if we want to work within the context of browsers we
+            // need to figure out some sort of allocation scheme for the main
+            // thread where when there's contention on the global malloc lock we
+            // do... something.
+            //
+            // Possible ideas include:
+            //
+            // 1. Attempt to acquire the global lock. If it fails, fall back to
+            //    memory allocation via `memory.grow`. Later just ... somehow
+            //    ... inject this raw page back into the main allocator as it
+            //    gets sliced up over time. This strategy has the downside of
+            //    forcing allocation of a page to happen whenever the main
+            //    thread contents with other threads, which is unfortunate.
+            //
+            // 2. Maintain a form of "two level" allocator scheme where the main
+            //    thread has its own allocator. Somehow this allocator would
+            //    also be balanced with a global allocator, not only to have
+            //    allocations cross between threads but also to ensure that the
+            //    two allocators stay "balanced" in terms of free'd memory and
+            //    such. This, however, seems significantly complicated.
+            //
+            // Out of a lack of other ideas, the current strategy implemented
+            // here is to simply spin. Typical spin loop algorithms have some
+            // form of "hint" here to the CPU that it's what we're doing to
+            // ensure that the CPU doesn't get too hot, but wasm doesn't have
+            // such an instruction.
+            //
+            // To be clear, spinning here is not a great solution.
+            // Another thread with the lock may take quite a long time to wake
+            // up. For example it could be in `memory.grow` or it could be
+            // evicted from the CPU for a timeslice like 10ms. For these periods
+            // of time our thread will "helpfully" sit here and eat CPU time
+            // until it itself is evicted or the lock holder finishes. This
+            // means we're just burning and wasting CPU time to no one's
+            // benefit.
+            //
+            // Spinning does have the nice properties, though, of being
+            // semantically correct, being fair to all threads for memory
+            // allocation, and being simple enough to implement.
+            //
+            // This will surely (hopefully) be replaced in the future with a
+            // real memory allocator that can handle the restriction of the main
+            // thread.
+            //
+            //
+            // FIXME: We can also possibly add an optimization here to detect
+            // when a thread is the main thread or not and block on all
+            // non-main-thread threads. Currently, however, we have no way
+            // of knowing which wasm thread is on the browser main thread, but
+            // if we could figure out we could at least somewhat mitigate the
+            // cost of this spinning.
         }
     }
 
@@ -76,12 +137,16 @@ mod lock {
         fn drop(&mut self) {
             let r = LOCKED.swap(0, SeqCst);
             debug_assert_eq!(r, 1);
-            unsafe {
-                wasm32::atomic_notify(
-                    &LOCKED as *const AtomicI32 as *mut i32,
-                    1, // only one thread
-                );
-            }
+
+            // Note that due to the above logic we don't actually need to wake
+            // anyone up, but if we did it'd likely look something like this:
+            //
+            //     unsafe {
+            //         core::arch::wasm32::atomic_notify(
+            //             &LOCKED as *const AtomicI32 as *mut i32,
+            //             1, //     only one thread
+            //         );
+            //     }
         }
     }
 }

From 710988ad603c52657c72a7f1028415e3e244a97c Mon Sep 17 00:00:00 2001
From: YunQiang Su <syq@debian.org>
Date: Tue, 5 Mar 2019 23:28:15 +0800
Subject: [PATCH 09/22] MIPS: add r6 support

MIPS r6 is quite different with the previous version.
It use some new target triples:
  mipsisa32r6-unknown-linux-gnu
  mipsisa32r6el-unknown-linux-gnu
  mipsisa64r6-unknown-linux-gnuabi64
  mipsisa64r6el-unknown-linux-gnuabi64

This patch has been tested with Debian Port for mips64r6el,
and the support of these triples also is included in llvm:
  https://reviews.llvm.org/rGe58c45a695f39004710b6ce940d489fee800dbd3
---
 .../spec/mipsisa32r6_unknown_linux_gnu.rs     | 23 ++++++++++++++++++
 .../spec/mipsisa32r6el_unknown_linux_gnu.rs   | 24 +++++++++++++++++++
 .../mipsisa64r6_unknown_linux_gnuabi64.rs     | 24 +++++++++++++++++++
 .../mipsisa64r6el_unknown_linux_gnuabi64.rs   | 24 +++++++++++++++++++
 src/librustc_target/spec/mod.rs               |  4 ++++
 src/tools/build-manifest/src/main.rs          |  8 +++++++
 src/tools/compiletest/src/util.rs             |  8 +++++++
 7 files changed, 115 insertions(+)
 create mode 100644 src/librustc_target/spec/mipsisa32r6_unknown_linux_gnu.rs
 create mode 100644 src/librustc_target/spec/mipsisa32r6el_unknown_linux_gnu.rs
 create mode 100644 src/librustc_target/spec/mipsisa64r6_unknown_linux_gnuabi64.rs
 create mode 100644 src/librustc_target/spec/mipsisa64r6el_unknown_linux_gnuabi64.rs

diff --git a/src/librustc_target/spec/mipsisa32r6_unknown_linux_gnu.rs b/src/librustc_target/spec/mipsisa32r6_unknown_linux_gnu.rs
new file mode 100644
index 0000000000000..f47291458492e
--- /dev/null
+++ b/src/librustc_target/spec/mipsisa32r6_unknown_linux_gnu.rs
@@ -0,0 +1,23 @@
+use crate::spec::{LinkerFlavor, Target, TargetOptions, TargetResult};
+
+pub fn target() -> TargetResult {
+    Ok(Target {
+        llvm_target: "mipsisa32r6-unknown-linux-gnu".to_string(),
+        target_endian: "big".to_string(),
+        target_pointer_width: "32".to_string(),
+        target_c_int_width: "32".to_string(),
+        data_layout: "E-m:m-p:32:32-i8:8:32-i16:16:32-i64:64-n32-S64".to_string(),
+        arch: "mips".to_string(),
+        target_os: "linux".to_string(),
+        target_env: "gnu".to_string(),
+        target_vendor: "unknown".to_string(),
+        linker_flavor: LinkerFlavor::Gcc,
+        options: TargetOptions {
+            cpu: "mips32r6".to_string(),
+            features: "+mips32r6".to_string(),
+            max_atomic_width: Some(32),
+
+            ..super::linux_base::opts()
+        },
+    })
+}
diff --git a/src/librustc_target/spec/mipsisa32r6el_unknown_linux_gnu.rs b/src/librustc_target/spec/mipsisa32r6el_unknown_linux_gnu.rs
new file mode 100644
index 0000000000000..f4f98d33571f0
--- /dev/null
+++ b/src/librustc_target/spec/mipsisa32r6el_unknown_linux_gnu.rs
@@ -0,0 +1,24 @@
+use crate::spec::{LinkerFlavor, Target, TargetOptions, TargetResult};
+
+pub fn target() -> TargetResult {
+    Ok(Target {
+        llvm_target: "mipsisa32r6el-unknown-linux-gnu".to_string(),
+        target_endian: "little".to_string(),
+        target_pointer_width: "32".to_string(),
+        target_c_int_width: "32".to_string(),
+        data_layout: "e-m:m-p:32:32-i8:8:32-i16:16:32-i64:64-n32-S64".to_string(),
+        arch: "mips".to_string(),
+        target_os: "linux".to_string(),
+        target_env: "gnu".to_string(),
+        target_vendor: "unknown".to_string(),
+        linker_flavor: LinkerFlavor::Gcc,
+
+        options: TargetOptions {
+            cpu: "mips32r6".to_string(),
+            features: "+mips32r6".to_string(),
+            max_atomic_width: Some(32),
+
+            ..super::linux_base::opts()
+        },
+    })
+}
diff --git a/src/librustc_target/spec/mipsisa64r6_unknown_linux_gnuabi64.rs b/src/librustc_target/spec/mipsisa64r6_unknown_linux_gnuabi64.rs
new file mode 100644
index 0000000000000..7faed3adc79cc
--- /dev/null
+++ b/src/librustc_target/spec/mipsisa64r6_unknown_linux_gnuabi64.rs
@@ -0,0 +1,24 @@
+use crate::spec::{LinkerFlavor, Target, TargetOptions, TargetResult};
+
+pub fn target() -> TargetResult {
+    Ok(Target {
+        llvm_target: "mipsisa64r6-unknown-linux-gnuabi64".to_string(),
+        target_endian: "big".to_string(),
+        target_pointer_width: "64".to_string(),
+        target_c_int_width: "32".to_string(),
+        data_layout: "E-m:e-i8:8:32-i16:16:32-i64:64-n32:64-S128".to_string(),
+        arch: "mips64".to_string(),
+        target_os: "linux".to_string(),
+        target_env: "gnu".to_string(),
+        target_vendor: "unknown".to_string(),
+        linker_flavor: LinkerFlavor::Gcc,
+        options: TargetOptions {
+            // NOTE(mips64r6) matches C toolchain
+            cpu: "mips64r6".to_string(),
+            features: "+mips64r6".to_string(),
+            max_atomic_width: Some(64),
+
+            ..super::linux_base::opts()
+        },
+    })
+}
diff --git a/src/librustc_target/spec/mipsisa64r6el_unknown_linux_gnuabi64.rs b/src/librustc_target/spec/mipsisa64r6el_unknown_linux_gnuabi64.rs
new file mode 100644
index 0000000000000..58a814a759eb8
--- /dev/null
+++ b/src/librustc_target/spec/mipsisa64r6el_unknown_linux_gnuabi64.rs
@@ -0,0 +1,24 @@
+use crate::spec::{LinkerFlavor, Target, TargetOptions, TargetResult};
+
+pub fn target() -> TargetResult {
+    Ok(Target {
+        llvm_target: "mipsisa64r6el-unknown-linux-gnuabi64".to_string(),
+        target_endian: "little".to_string(),
+        target_pointer_width: "64".to_string(),
+        target_c_int_width: "32".to_string(),
+        data_layout: "e-m:e-i8:8:32-i16:16:32-i64:64-n32:64-S128".to_string(),
+        arch: "mips64".to_string(),
+        target_os: "linux".to_string(),
+        target_env: "gnu".to_string(),
+        target_vendor: "unknown".to_string(),
+        linker_flavor: LinkerFlavor::Gcc,
+        options: TargetOptions {
+            // NOTE(mips64r6) matches C toolchain
+            cpu: "mips64r6".to_string(),
+            features: "+mips64r6".to_string(),
+            max_atomic_width: Some(64),
+
+            ..super::linux_base::opts()
+        },
+    })
+}
diff --git a/src/librustc_target/spec/mod.rs b/src/librustc_target/spec/mod.rs
index bef2afc7b6292..1020464ca0b06 100644
--- a/src/librustc_target/spec/mod.rs
+++ b/src/librustc_target/spec/mod.rs
@@ -335,6 +335,10 @@ supported_targets! {
     ("mips-unknown-linux-gnu", mips_unknown_linux_gnu),
     ("mips64-unknown-linux-gnuabi64", mips64_unknown_linux_gnuabi64),
     ("mips64el-unknown-linux-gnuabi64", mips64el_unknown_linux_gnuabi64),
+    ("mipsisa32r6-unknown-linux-gnu", mipsisa32r6_unknown_linux_gnu),
+    ("mipsisa32r6el-unknown-linux-gnu", mipsisa32r6el_unknown_linux_gnu),
+    ("mipsisa64r6-unknown-linux-gnuabi64", mipsisa64r6_unknown_linux_gnuabi64),
+    ("mipsisa64r6el-unknown-linux-gnuabi64", mipsisa64r6el_unknown_linux_gnuabi64),
     ("mipsel-unknown-linux-gnu", mipsel_unknown_linux_gnu),
     ("powerpc-unknown-linux-gnu", powerpc_unknown_linux_gnu),
     ("powerpc-unknown-linux-gnuspe", powerpc_unknown_linux_gnuspe),
diff --git a/src/tools/build-manifest/src/main.rs b/src/tools/build-manifest/src/main.rs
index 8d87c404d0b28..6eb12ea016186 100644
--- a/src/tools/build-manifest/src/main.rs
+++ b/src/tools/build-manifest/src/main.rs
@@ -23,6 +23,10 @@ static HOSTS: &'static [&'static str] = &[
     "mips64-unknown-linux-gnuabi64",
     "mips64el-unknown-linux-gnuabi64",
     "mipsel-unknown-linux-gnu",
+    "mipsisa32r6-unknown-linux-gnu",
+    "mipsisa32r6el-unknown-linux-gnu",
+    "mipsisa64r6-unknown-linux-gnuabi64",
+    "mipsisa64r6el-unknown-linux-gnuabi64",
     "powerpc-unknown-linux-gnu",
     "powerpc64-unknown-linux-gnu",
     "powerpc64le-unknown-linux-gnu",
@@ -77,6 +81,10 @@ static TARGETS: &'static [&'static str] = &[
     "mips-unknown-linux-musl",
     "mips64-unknown-linux-gnuabi64",
     "mips64el-unknown-linux-gnuabi64",
+    "mipsisa32r6-unknown-linux-gnu",
+    "mipsisa32r6el-unknown-linux-gnu",
+    "mipsisa64r6-unknown-linux-gnuabi64",
+    "mipsisa64r6el-unknown-linux-gnuabi64",
     "mipsel-unknown-linux-gnu",
     "mipsel-unknown-linux-musl",
     "nvptx64-nvidia-cuda",
diff --git a/src/tools/compiletest/src/util.rs b/src/tools/compiletest/src/util.rs
index 240287fa248bd..3533dcdc988a1 100644
--- a/src/tools/compiletest/src/util.rs
+++ b/src/tools/compiletest/src/util.rs
@@ -49,7 +49,15 @@ const ARCH_TABLE: &'static [(&'static str, &'static str)] = &[
     ("mips", "mips"),
     ("mips64", "mips64"),
     ("mips64el", "mips64"),
+    ("mipsisa32r6", "mips"),
+    ("mipsisa32r6el", "mips"),
+    ("mipsisa64r6", "mips64"),
+    ("mipsisa64r6el", "mips64"),
     ("mipsel", "mips"),
+    ("mipsisa32r6", "mips"),
+    ("mipsisa32r6el", "mips"),
+    ("mipsisa64r6", "mips64"),
+    ("mipsisa64r6el", "mips64"),
     ("msp430", "msp430"),
     ("powerpc", "powerpc"),
     ("powerpc64", "powerpc64"),

From 7e8758bc8063ae52ef3f28ff77d5544565b364e0 Mon Sep 17 00:00:00 2001
From: Jordan Rhee <jordanrh@microsoft.com>
Date: Tue, 5 Mar 2019 13:56:39 -0800
Subject: [PATCH 10/22] Update compiler_builtins to 0.1.7

---
 Cargo.lock | 32 ++++++++++++++++----------------
 1 file changed, 16 insertions(+), 16 deletions(-)

diff --git a/Cargo.lock b/Cargo.lock
index 19dadaa14005a..daa072c58841d 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -17,7 +17,7 @@ dependencies = [
 name = "alloc"
 version = "0.0.0"
 dependencies = [
- "compiler_builtins 0.1.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "compiler_builtins 0.1.7 (registry+https://github.com/rust-lang/crates.io-index)",
  "core 0.0.0",
  "rand 0.6.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "rand_xorshift 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -106,7 +106,7 @@ version = "0.1.27"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "cc 1.0.28 (registry+https://github.com/rust-lang/crates.io-index)",
- "compiler_builtins 0.1.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "compiler_builtins 0.1.7 (registry+https://github.com/rust-lang/crates.io-index)",
  "libc 0.2.46 (registry+https://github.com/rust-lang/crates.io-index)",
  "rustc-std-workspace-core 1.0.0",
 ]
@@ -463,7 +463,7 @@ dependencies = [
 
 [[package]]
 name = "compiler_builtins"
-version = "0.1.5"
+version = "0.1.7"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "cc 1.0.28 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -748,7 +748,7 @@ name = "dlmalloc"
 version = "0.1.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "compiler_builtins 0.1.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "compiler_builtins 0.1.7 (registry+https://github.com/rust-lang/crates.io-index)",
  "libc 0.2.46 (registry+https://github.com/rust-lang/crates.io-index)",
  "rustc-std-workspace-core 1.0.0",
 ]
@@ -906,7 +906,7 @@ name = "fortanix-sgx-abi"
 version = "0.3.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "compiler_builtins 0.1.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "compiler_builtins 0.1.7 (registry+https://github.com/rust-lang/crates.io-index)",
  "rustc-std-workspace-core 1.0.0",
 ]
 
@@ -1739,7 +1739,7 @@ dependencies = [
 name = "panic_abort"
 version = "0.0.0"
 dependencies = [
- "compiler_builtins 0.1.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "compiler_builtins 0.1.7 (registry+https://github.com/rust-lang/crates.io-index)",
  "core 0.0.0",
  "libc 0.2.46 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
@@ -1749,7 +1749,7 @@ name = "panic_unwind"
 version = "0.0.0"
 dependencies = [
  "alloc 0.0.0",
- "compiler_builtins 0.1.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "compiler_builtins 0.1.7 (registry+https://github.com/rust-lang/crates.io-index)",
  "core 0.0.0",
  "libc 0.2.46 (registry+https://github.com/rust-lang/crates.io-index)",
  "unwind 0.0.0",
@@ -1954,7 +1954,7 @@ name = "profiler_builtins"
 version = "0.0.0"
 dependencies = [
  "cc 1.0.28 (registry+https://github.com/rust-lang/crates.io-index)",
- "compiler_builtins 0.1.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "compiler_builtins 0.1.7 (registry+https://github.com/rust-lang/crates.io-index)",
  "core 0.0.0",
 ]
 
@@ -2485,7 +2485,7 @@ name = "rustc-demangle"
 version = "0.1.10"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "compiler_builtins 0.1.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "compiler_builtins 0.1.7 (registry+https://github.com/rust-lang/crates.io-index)",
  "rustc-std-workspace-core 1.0.0",
 ]
 
@@ -2585,7 +2585,7 @@ dependencies = [
  "alloc 0.0.0",
  "build_helper 0.1.0",
  "cmake 0.1.33 (registry+https://github.com/rust-lang/crates.io-index)",
- "compiler_builtins 0.1.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "compiler_builtins 0.1.7 (registry+https://github.com/rust-lang/crates.io-index)",
  "core 0.0.0",
 ]
 
@@ -2813,7 +2813,7 @@ dependencies = [
  "alloc 0.0.0",
  "build_helper 0.1.0",
  "cmake 0.1.33 (registry+https://github.com/rust-lang/crates.io-index)",
- "compiler_builtins 0.1.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "compiler_builtins 0.1.7 (registry+https://github.com/rust-lang/crates.io-index)",
  "core 0.0.0",
 ]
 
@@ -2864,7 +2864,7 @@ dependencies = [
  "alloc 0.0.0",
  "build_helper 0.1.0",
  "cmake 0.1.33 (registry+https://github.com/rust-lang/crates.io-index)",
- "compiler_builtins 0.1.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "compiler_builtins 0.1.7 (registry+https://github.com/rust-lang/crates.io-index)",
  "core 0.0.0",
 ]
 
@@ -2980,7 +2980,7 @@ dependencies = [
  "alloc 0.0.0",
  "build_helper 0.1.0",
  "cmake 0.1.33 (registry+https://github.com/rust-lang/crates.io-index)",
- "compiler_builtins 0.1.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "compiler_builtins 0.1.7 (registry+https://github.com/rust-lang/crates.io-index)",
  "core 0.0.0",
 ]
 
@@ -3252,7 +3252,7 @@ dependencies = [
  "alloc 0.0.0",
  "backtrace-sys 0.1.27 (registry+https://github.com/rust-lang/crates.io-index)",
  "cc 1.0.28 (registry+https://github.com/rust-lang/crates.io-index)",
- "compiler_builtins 0.1.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "compiler_builtins 0.1.7 (registry+https://github.com/rust-lang/crates.io-index)",
  "core 0.0.0",
  "dlmalloc 0.1.3 (registry+https://github.com/rust-lang/crates.io-index)",
  "fortanix-sgx-abi 0.3.2 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -3822,7 +3822,7 @@ dependencies = [
 name = "unwind"
 version = "0.0.0"
 dependencies = [
- "compiler_builtins 0.1.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "compiler_builtins 0.1.7 (registry+https://github.com/rust-lang/crates.io-index)",
  "core 0.0.0",
  "libc 0.2.46 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
@@ -4018,7 +4018,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 "checksum colored 1.6.0 (registry+https://github.com/rust-lang/crates.io-index)" = "b0aa3473e85a3161b59845d6096b289bb577874cafeaf75ea1b1beaa6572c7fc"
 "checksum commoncrypto 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)" = "d056a8586ba25a1e4d61cb090900e495952c7886786fc55f909ab2f819b69007"
 "checksum commoncrypto-sys 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)" = "1fed34f46747aa73dfaa578069fd8279d2818ade2b55f38f22a9401c7f4083e2"
-"checksum compiler_builtins 0.1.5 (registry+https://github.com/rust-lang/crates.io-index)" = "6711d51cb46744dd8305293cc3fbc392aaff7a8f5095a7c4fae1e5113ef07c96"
+"checksum compiler_builtins 0.1.7 (registry+https://github.com/rust-lang/crates.io-index)" = "d7be038c8f003625c494e97c09bbcef65582b73f6aa86975f5273d8eba4c9d4c"
 "checksum compiletest_rs 0.3.19 (registry+https://github.com/rust-lang/crates.io-index)" = "56c799b1f7142badf3b047b4c1f2074cc96b6b784fb2432f2ed9c87da0a03749"
 "checksum constant_time_eq 0.1.3 (registry+https://github.com/rust-lang/crates.io-index)" = "8ff012e225ce166d4422e0e78419d901719760f62ae2b7969ca6b564d1b54a9e"
 "checksum core-foundation 0.6.3 (registry+https://github.com/rust-lang/crates.io-index)" = "4e2640d6d0bf22e82bed1b73c6aef8d5dd31e5abe6666c57e6d45e2649f4f887"

From 00887f39d199bc63730d0dd19f8726451fdd5758 Mon Sep 17 00:00:00 2001
From: Wesley Norris <repnop@outlook.com>
Date: Mon, 4 Mar 2019 20:00:28 -0500
Subject: [PATCH 11/22] Adds diagnostic message and UI test.

---
 src/libsyntax/parse/parser.rs         | 10 +++++++++-
 src/test/ui/issues/issue-56031.rs     |  5 +++++
 src/test/ui/issues/issue-56031.stderr | 10 ++++++++++
 3 files changed, 24 insertions(+), 1 deletion(-)
 create mode 100644 src/test/ui/issues/issue-56031.rs
 create mode 100644 src/test/ui/issues/issue-56031.stderr

diff --git a/src/libsyntax/parse/parser.rs b/src/libsyntax/parse/parser.rs
index fd5038a8614f2..330be1133ca4b 100644
--- a/src/libsyntax/parse/parser.rs
+++ b/src/libsyntax/parse/parser.rs
@@ -6716,8 +6716,16 @@ impl<'a> Parser<'a> {
             ast::ImplPolarity::Positive
         };
 
+        let possible_missing_trait = self.look_ahead(0, |t| t.is_keyword(keywords::For));
+
         // Parse both types and traits as a type, then reinterpret if necessary.
-        let ty_first = self.parse_ty()?;
+        let ty_first = self.parse_ty().map_err(|mut err| {
+            if possible_missing_trait {
+                err.help("did you forget a trait name after `impl`?");
+            }
+
+            err
+        })?;
 
         // If `for` is missing we try to recover.
         let has_for = self.eat_keyword(keywords::For);
diff --git a/src/test/ui/issues/issue-56031.rs b/src/test/ui/issues/issue-56031.rs
new file mode 100644
index 0000000000000..7dbda3e46d13c
--- /dev/null
+++ b/src/test/ui/issues/issue-56031.rs
@@ -0,0 +1,5 @@
+struct T;
+
+impl for T {}
+
+fn main() {}
diff --git a/src/test/ui/issues/issue-56031.stderr b/src/test/ui/issues/issue-56031.stderr
new file mode 100644
index 0000000000000..dd4f95341ff22
--- /dev/null
+++ b/src/test/ui/issues/issue-56031.stderr
@@ -0,0 +1,10 @@
+error: expected `<`, found `T`
+  --> $DIR/issue-56031.rs:3:10
+   |
+LL | impl for T {}
+   |          ^ expected `<` here
+   |
+   = help: did you forget a trait name after `impl`?
+
+error: aborting due to previous error
+

From e19b2289594746ce733588ac444df3fefaad4912 Mon Sep 17 00:00:00 2001
From: Vadim Petrochenkov <vadim.petrochenkov@gmail.com>
Date: Thu, 7 Mar 2019 23:18:03 +0300
Subject: [PATCH 12/22] Improve recovery for missing trait in a trait impl

---
 src/libsyntax/parse/parser.rs         | 22 +++++++++++-----------
 src/test/ui/issues/issue-56031.rs     |  1 +
 src/test/ui/issues/issue-56031.stderr |  8 +++-----
 3 files changed, 15 insertions(+), 16 deletions(-)

diff --git a/src/libsyntax/parse/parser.rs b/src/libsyntax/parse/parser.rs
index 330be1133ca4b..64f413e6dd8ee 100644
--- a/src/libsyntax/parse/parser.rs
+++ b/src/libsyntax/parse/parser.rs
@@ -6716,16 +6716,16 @@ impl<'a> Parser<'a> {
             ast::ImplPolarity::Positive
         };
 
-        let possible_missing_trait = self.look_ahead(0, |t| t.is_keyword(keywords::For));
-
         // Parse both types and traits as a type, then reinterpret if necessary.
-        let ty_first = self.parse_ty().map_err(|mut err| {
-            if possible_missing_trait {
-                err.help("did you forget a trait name after `impl`?");
-            }
-
-            err
-        })?;
+        let err_path = |span| ast::Path::from_ident(Ident::new(keywords::Invalid.name(), span));
+        let ty_first = if self.token.is_keyword(keywords::For) &&
+                          self.look_ahead(1, |t| t != &token::Lt) {
+            let span = self.prev_span.between(self.span);
+            self.struct_span_err(span, "missing trait in a trait impl").emit();
+            P(Ty { node: TyKind::Path(None, err_path(span)), span, id: ast::DUMMY_NODE_ID })
+        } else {
+            self.parse_ty()?
+        };
 
         // If `for` is missing we try to recover.
         let has_for = self.eat_keyword(keywords::For);
@@ -6734,7 +6734,7 @@ impl<'a> Parser<'a> {
         let ty_second = if self.token == token::DotDot {
             // We need to report this error after `cfg` expansion for compatibility reasons
             self.bump(); // `..`, do not add it to expected tokens
-            Some(P(Ty { node: TyKind::Err, span: self.prev_span, id: ast::DUMMY_NODE_ID }))
+            Some(DummyResult::raw_ty(self.prev_span, true))
         } else if has_for || self.token.can_begin_type() {
             Some(self.parse_ty()?)
         } else {
@@ -6764,7 +6764,7 @@ impl<'a> Parser<'a> {
                     TyKind::Path(None, path) => path,
                     _ => {
                         self.span_err(ty_first.span, "expected a trait, found type");
-                        ast::Path::from_ident(Ident::new(keywords::Invalid.name(), ty_first.span))
+                        err_path(ty_first.span)
                     }
                 };
                 let trait_ref = TraitRef { path, ref_id: ty_first.id };
diff --git a/src/test/ui/issues/issue-56031.rs b/src/test/ui/issues/issue-56031.rs
index 7dbda3e46d13c..b68f56814678c 100644
--- a/src/test/ui/issues/issue-56031.rs
+++ b/src/test/ui/issues/issue-56031.rs
@@ -1,5 +1,6 @@
 struct T;
 
 impl for T {}
+//~^ ERROR missing trait in a trait impl
 
 fn main() {}
diff --git a/src/test/ui/issues/issue-56031.stderr b/src/test/ui/issues/issue-56031.stderr
index dd4f95341ff22..3d7acee0a56eb 100644
--- a/src/test/ui/issues/issue-56031.stderr
+++ b/src/test/ui/issues/issue-56031.stderr
@@ -1,10 +1,8 @@
-error: expected `<`, found `T`
-  --> $DIR/issue-56031.rs:3:10
+error: missing trait in a trait impl
+  --> $DIR/issue-56031.rs:3:5
    |
 LL | impl for T {}
-   |          ^ expected `<` here
-   |
-   = help: did you forget a trait name after `impl`?
+   |     ^
 
 error: aborting due to previous error
 

From 0a505a71d3b8d61e982b305caf6d39c227c05957 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Esteban=20K=C3=BCber?= <esteban@kuber.com.ar>
Date: Sat, 2 Mar 2019 10:38:20 -0800
Subject: [PATCH 13/22] Parse lifetimes that start with a number and give
 specific error

---
 src/libsyntax/parse/lexer/mod.rs           | 24 ++++++++++++++++------
 src/test/ui/parser/numeric-lifetime.rs     |  8 ++++++++
 src/test/ui/parser/numeric-lifetime.stderr | 24 ++++++++++++++++++++++
 3 files changed, 50 insertions(+), 6 deletions(-)
 create mode 100644 src/test/ui/parser/numeric-lifetime.rs
 create mode 100644 src/test/ui/parser/numeric-lifetime.stderr

diff --git a/src/libsyntax/parse/lexer/mod.rs b/src/libsyntax/parse/lexer/mod.rs
index a7cde5fbb92cd..f45f5e65312c2 100644
--- a/src/libsyntax/parse/lexer/mod.rs
+++ b/src/libsyntax/parse/lexer/mod.rs
@@ -1423,15 +1423,17 @@ impl<'a> StringReader<'a> {
 
                 // If the character is an ident start not followed by another single
                 // quote, then this is a lifetime name:
-                if ident_start(Some(c2)) && !self.ch_is('\'') {
+                if (ident_start(Some(c2)) || c2.is_numeric()) && !self.ch_is('\'') {
                     while ident_continue(self.ch) {
                         self.bump();
                     }
                     // lifetimes shouldn't end with a single quote
                     // if we find one, then this is an invalid character literal
                     if self.ch_is('\'') {
-                        self.err_span_(start_with_quote, self.next_pos,
-                                "character literal may only contain one codepoint");
+                        self.err_span_(
+                            start_with_quote,
+                            self.next_pos,
+                            "character literal may only contain one codepoint");
                         self.bump();
                         return Ok(token::Literal(token::Err(Symbol::intern("??")), None))
 
@@ -1444,6 +1446,16 @@ impl<'a> StringReader<'a> {
                         self.mk_ident(&format!("'{}", lifetime_name))
                     });
 
+                    if c2.is_numeric() {
+                        // this is a recovered lifetime written `'1`, error but accept it
+                        self.err_span_(
+                            start_with_quote,
+                            self.pos,
+                            "lifetimes can't start with a number",
+                        );
+                    }
+
+
                     return Ok(token::Lifetime(ident));
                 }
 
@@ -1873,13 +1885,14 @@ fn is_block_doc_comment(s: &str) -> bool {
     res
 }
 
+/// Determine whether `c` is a valid start for an ident.
 fn ident_start(c: Option<char>) -> bool {
     let c = match c {
         Some(c) => c,
         None => return false,
     };
 
-    (c >= 'a' && c <= 'z') || (c >= 'A' && c <= 'Z') || c == '_' || (c > '\x7f' && c.is_xid_start())
+    (c.is_alphabetic() || c == '_' || (c > '\x7f' && c.is_xid_start()))
 }
 
 fn ident_continue(c: Option<char>) -> bool {
@@ -1888,8 +1901,7 @@ fn ident_continue(c: Option<char>) -> bool {
         None => return false,
     };
 
-    (c >= 'a' && c <= 'z') || (c >= 'A' && c <= 'Z') || (c >= '0' && c <= '9') || c == '_' ||
-    (c > '\x7f' && c.is_xid_continue())
+    (c.is_alphabetic() || c.is_numeric() || c == '_' || (c > '\x7f' && c.is_xid_continue()))
 }
 
 #[inline]
diff --git a/src/test/ui/parser/numeric-lifetime.rs b/src/test/ui/parser/numeric-lifetime.rs
new file mode 100644
index 0000000000000..3483975a3cb8e
--- /dev/null
+++ b/src/test/ui/parser/numeric-lifetime.rs
@@ -0,0 +1,8 @@
+struct S<'1> { s: &'1 usize }
+//~^ ERROR lifetimes can't start with a number
+//~| ERROR lifetimes can't start with a number
+fn main() {
+    // verify that the parse error doesn't stop type checking
+    let x: usize = "";
+    //~^ ERROR mismatched types
+}
diff --git a/src/test/ui/parser/numeric-lifetime.stderr b/src/test/ui/parser/numeric-lifetime.stderr
new file mode 100644
index 0000000000000..1bbc508d57d4b
--- /dev/null
+++ b/src/test/ui/parser/numeric-lifetime.stderr
@@ -0,0 +1,24 @@
+error: lifetimes can't start with a number
+  --> $DIR/numeric-lifetime.rs:1:10
+   |
+LL | struct S<'1> { s: &'1 usize }
+   |          ^^
+
+error: lifetimes can't start with a number
+  --> $DIR/numeric-lifetime.rs:1:20
+   |
+LL | struct S<'1> { s: &'1 usize }
+   |                    ^^
+
+error[E0308]: mismatched types
+  --> $DIR/numeric-lifetime.rs:6:20
+   |
+LL |     let x: usize = "";
+   |                    ^^ expected usize, found reference
+   |
+   = note: expected type `usize`
+              found type `&'static str`
+
+error: aborting due to 3 previous errors
+
+For more information about this error, try `rustc --explain E0308`.

From 9aa89b25232b79b93dc122e86b8071fb14fc4e04 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Esteban=20K=C3=BCber?= <esteban@kuber.com.ar>
Date: Fri, 8 Mar 2019 19:08:28 -0800
Subject: [PATCH 14/22] When encountetring `||{}()`, suggest the likely
 intended `(||{})()`

---
 src/librustc_typeck/check/callee.rs           | 35 ++++++++++++++++++-
 .../suggest-on-bare-closure-call.rs           |  4 +++
 .../suggest-on-bare-closure-call.stderr       | 15 ++++++++
 3 files changed, 53 insertions(+), 1 deletion(-)
 create mode 100644 src/test/ui/suggestions/suggest-on-bare-closure-call.rs
 create mode 100644 src/test/ui/suggestions/suggest-on-bare-closure-call.stderr

diff --git a/src/librustc_typeck/check/callee.rs b/src/librustc_typeck/check/callee.rs
index 0a4c0eb3aff72..15ae39600f6b4 100644
--- a/src/librustc_typeck/check/callee.rs
+++ b/src/librustc_typeck/check/callee.rs
@@ -2,7 +2,7 @@ use super::autoderef::Autoderef;
 use super::method::MethodCallee;
 use super::{Expectation, FnCtxt, Needs, TupleArgumentsFlag};
 
-use errors::Applicability;
+use errors::{Applicability, DiagnosticBuilder};
 use hir::def::Def;
 use hir::def_id::{DefId, LOCAL_CRATE};
 use rustc::ty::adjustment::{Adjust, Adjustment, AllowTwoPhase, AutoBorrow, AutoBorrowMutability};
@@ -232,6 +232,32 @@ impl<'a, 'gcx, 'tcx> FnCtxt<'a, 'gcx, 'tcx> {
         None
     }
 
+    /// Give appropriate suggestion when encountering `||{/* not callable */}()`, where the
+    /// likely intention is to call the closure, suggest `(||{})()`. (#55851)
+    fn identify_bad_closure_def_and_call(
+        &self,
+        err: &mut DiagnosticBuilder<'a>,
+        hir_id: hir::HirId,
+        callee_node: &hir::ExprKind,
+        callee_span: Span,
+    ) {
+        let hir_id = self.tcx.hir().get_parent_node_by_hir_id(hir_id);
+        let parent_node = self.tcx.hir().get_by_hir_id(hir_id);
+        if let (
+            hir::Node::Expr(hir::Expr { node: hir::ExprKind::Closure(_, _, _, sp, ..), .. }),
+            hir::ExprKind::Block(..),
+        ) = (parent_node, callee_node) {
+            let start = sp.shrink_to_lo();
+            let end = self.tcx.sess.source_map().next_point(callee_span);
+            err.multipart_suggestion(
+                "if you meant to create this closure and immediately call it, surround the \
+                closure with parenthesis",
+                vec![(start, "(".to_string()), (end, ")".to_string())],
+                Applicability::MaybeIncorrect,
+            );
+        }
+    }
+
     fn confirm_builtin_call(
         &self,
         call_expr: &hir::Expr,
@@ -268,6 +294,13 @@ impl<'a, 'gcx, 'tcx> FnCtxt<'a, 'gcx, 'tcx> {
                         }
                     );
 
+                    self.identify_bad_closure_def_and_call(
+                        &mut err,
+                        call_expr.hir_id,
+                        &callee.node,
+                        callee.span,
+                    );
+
                     if let Some(ref path) = unit_variant {
                         err.span_suggestion(
                             call_expr.span,
diff --git a/src/test/ui/suggestions/suggest-on-bare-closure-call.rs b/src/test/ui/suggestions/suggest-on-bare-closure-call.rs
new file mode 100644
index 0000000000000..355708c08ec2f
--- /dev/null
+++ b/src/test/ui/suggestions/suggest-on-bare-closure-call.rs
@@ -0,0 +1,4 @@
+fn main() {
+    let _ = ||{}();
+    //~^ ERROR expected function, found `()`
+}
diff --git a/src/test/ui/suggestions/suggest-on-bare-closure-call.stderr b/src/test/ui/suggestions/suggest-on-bare-closure-call.stderr
new file mode 100644
index 0000000000000..17001e3974c6d
--- /dev/null
+++ b/src/test/ui/suggestions/suggest-on-bare-closure-call.stderr
@@ -0,0 +1,15 @@
+error[E0618]: expected function, found `()`
+  --> $DIR/suggest-on-bare-closure-call.rs:2:15
+   |
+LL |     let _ = ||{}();
+   |               ^^--
+   |               |
+   |               call expression requires function
+help: if you meant to create this closure and immediately call it, surround the closure with parenthesis
+   |
+LL |     let _ = (||{})();
+   |             ^    ^
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0618`.

From a03e20db6d15fe1cdda64c0fbe934e36209a08f6 Mon Sep 17 00:00:00 2001
From: ishitatsuyuki <ishitatsuyuki@gmail.com>
Date: Thu, 31 Jan 2019 18:28:22 +0900
Subject: [PATCH 15/22] Fix fallout from #57667

---
 src/libsyntax/ptr.rs | 39 ++++++---------------------------------
 1 file changed, 6 insertions(+), 33 deletions(-)

diff --git a/src/libsyntax/ptr.rs b/src/libsyntax/ptr.rs
index bc43630ae59b3..9afcb7c4621c9 100644
--- a/src/libsyntax/ptr.rs
+++ b/src/libsyntax/ptr.rs
@@ -29,7 +29,7 @@
 use std::fmt::{self, Display, Debug};
 use std::iter::FromIterator;
 use std::ops::{Deref, DerefMut};
-use std::{mem, ptr, slice, vec};
+use std::{slice, vec};
 
 use serialize::{Encodable, Decodable, Encoder, Decoder};
 
@@ -66,45 +66,18 @@ impl<T: 'static> P<T> {
     pub fn map<F>(mut self, f: F) -> P<T> where
         F: FnOnce(T) -> T,
     {
-        let p: *mut T = &mut *self.ptr;
+        let x = f(*self.ptr);
+        *self.ptr = x;
 
-        // Leak self in case of panic.
-        // FIXME(eddyb) Use some sort of "free guard" that
-        // only deallocates, without dropping the pointee,
-        // in case the call the `f` below ends in a panic.
-        mem::forget(self);
-
-        unsafe {
-            ptr::write(p, f(ptr::read(p)));
-
-            // Recreate self from the raw pointer.
-            P { ptr: Box::from_raw(p) }
-        }
+        self
     }
 
     /// Optionally produce a new `P<T>` from `self` without reallocating.
     pub fn filter_map<F>(mut self, f: F) -> Option<P<T>> where
         F: FnOnce(T) -> Option<T>,
     {
-        let p: *mut T = &mut *self.ptr;
-
-        // Leak self in case of panic.
-        // FIXME(eddyb) Use some sort of "free guard" that
-        // only deallocates, without dropping the pointee,
-        // in case the call the `f` below ends in a panic.
-        mem::forget(self);
-
-        unsafe {
-            if let Some(v) = f(ptr::read(p)) {
-                ptr::write(p, v);
-
-                // Recreate self from the raw pointer.
-                Some(P { ptr: Box::from_raw(p) })
-            } else {
-                drop(Box::from_raw(p));
-                None
-            }
-        }
+        *self.ptr = f(*self.ptr)?;
+        Some(self)
     }
 }
 

From 967e7f4077247dab223ffd4b2e0c40341f9544a3 Mon Sep 17 00:00:00 2001
From: Vadim Petrochenkov <vadim.petrochenkov@gmail.com>
Date: Sat, 9 Mar 2019 16:15:40 +0300
Subject: [PATCH 16/22] resolve: Account for new importable entities

---
 src/librustc_resolve/build_reduced_graph.rs   | 18 +++++--------
 .../uniform-paths/auxiliary/cross-crate.rs    |  5 ++++
 .../ui/rust-2018/uniform-paths/cross-crate.rs | 11 ++++++++
 .../uniform-paths/cross-crate.stderr          | 26 +++++++++++++++++++
 4 files changed, 49 insertions(+), 11 deletions(-)
 create mode 100644 src/test/ui/rust-2018/uniform-paths/auxiliary/cross-crate.rs
 create mode 100644 src/test/ui/rust-2018/uniform-paths/cross-crate.rs
 create mode 100644 src/test/ui/rust-2018/uniform-paths/cross-crate.stderr

diff --git a/src/librustc_resolve/build_reduced_graph.rs b/src/librustc_resolve/build_reduced_graph.rs
index 29de5308a3cdb..21043a52fda22 100644
--- a/src/librustc_resolve/build_reduced_graph.rs
+++ b/src/librustc_resolve/build_reduced_graph.rs
@@ -639,10 +639,9 @@ impl<'a> Resolver<'a> {
         // but metadata cannot encode gensyms currently, so we create it here.
         // This is only a guess, two equivalent idents may incorrectly get different gensyms here.
         let ident = ident.gensym_if_underscore();
-        let def_id = def.def_id();
         let expansion = Mark::root(); // FIXME(jseyfried) intercrate hygiene
         match def {
-            Def::Mod(..) | Def::Enum(..) => {
+            Def::Mod(def_id) | Def::Enum(def_id) => {
                 let module = self.new_module(parent,
                                              ModuleKind::Def(def, ident.name),
                                              def_id,
@@ -650,13 +649,14 @@ impl<'a> Resolver<'a> {
                                              span);
                 self.define(parent, ident, TypeNS, (module, vis, DUMMY_SP, expansion));
             }
-            Def::Variant(..) | Def::TyAlias(..) | Def::ForeignTy(..) => {
+            Def::Variant(..) | Def::TyAlias(..) | Def::ForeignTy(..) | Def::Existential(..) |
+            Def::TraitAlias(..) | Def::PrimTy(..) | Def::ToolMod => {
                 self.define(parent, ident, TypeNS, (def, vis, DUMMY_SP, expansion));
             }
             Def::Fn(..) | Def::Static(..) | Def::Const(..) | Def::VariantCtor(..) => {
                 self.define(parent, ident, ValueNS, (def, vis, DUMMY_SP, expansion));
             }
-            Def::StructCtor(..) => {
+            Def::StructCtor(def_id, ..) => {
                 self.define(parent, ident, ValueNS, (def, vis, DUMMY_SP, expansion));
 
                 if let Some(struct_def_id) =
@@ -665,7 +665,7 @@ impl<'a> Resolver<'a> {
                     self.struct_constructors.insert(struct_def_id, (def, vis));
                 }
             }
-            Def::Trait(..) => {
+            Def::Trait(def_id) => {
                 let module_kind = ModuleKind::Def(def, ident.name);
                 let module = self.new_module(parent,
                                              module_kind,
@@ -686,18 +686,14 @@ impl<'a> Resolver<'a> {
                 }
                 module.populated.set(true);
             }
-            Def::Existential(..) |
-            Def::TraitAlias(..) => {
-                self.define(parent, ident, TypeNS, (def, vis, DUMMY_SP, expansion));
-            }
-            Def::Struct(..) | Def::Union(..) => {
+            Def::Struct(def_id) | Def::Union(def_id) => {
                 self.define(parent, ident, TypeNS, (def, vis, DUMMY_SP, expansion));
 
                 // Record field names for error reporting.
                 let field_names = self.cstore.struct_field_names_untracked(def_id);
                 self.insert_field_names(def_id, field_names);
             }
-            Def::Macro(..) => {
+            Def::Macro(..) | Def::NonMacroAttr(..) => {
                 self.define(parent, ident, MacroNS, (def, vis, DUMMY_SP, expansion));
             }
             _ => bug!("unexpected definition: {:?}", def)
diff --git a/src/test/ui/rust-2018/uniform-paths/auxiliary/cross-crate.rs b/src/test/ui/rust-2018/uniform-paths/auxiliary/cross-crate.rs
new file mode 100644
index 0000000000000..4aa5d1870000d
--- /dev/null
+++ b/src/test/ui/rust-2018/uniform-paths/auxiliary/cross-crate.rs
@@ -0,0 +1,5 @@
+// edition:2018
+
+pub use ignore as built_in_attr;
+pub use u8 as built_in_type;
+pub use rustfmt as tool_mod;
diff --git a/src/test/ui/rust-2018/uniform-paths/cross-crate.rs b/src/test/ui/rust-2018/uniform-paths/cross-crate.rs
new file mode 100644
index 0000000000000..27d6dbf4683e3
--- /dev/null
+++ b/src/test/ui/rust-2018/uniform-paths/cross-crate.rs
@@ -0,0 +1,11 @@
+// edition:2018
+// aux-build:cross-crate.rs
+
+extern crate cross_crate;
+use cross_crate::*;
+
+#[built_in_attr] //~ ERROR cannot use a built-in attribute through an import
+#[tool_mod::skip] //~ ERROR cannot use a tool module through an import
+fn main() {
+    let _: built_in_type; // OK
+}
diff --git a/src/test/ui/rust-2018/uniform-paths/cross-crate.stderr b/src/test/ui/rust-2018/uniform-paths/cross-crate.stderr
new file mode 100644
index 0000000000000..ccf66b54c529c
--- /dev/null
+++ b/src/test/ui/rust-2018/uniform-paths/cross-crate.stderr
@@ -0,0 +1,26 @@
+error: cannot use a built-in attribute through an import
+  --> $DIR/cross-crate.rs:7:3
+   |
+LL | #[built_in_attr] //~ ERROR cannot use a built-in attribute through an import
+   |   ^^^^^^^^^^^^^
+   |
+note: the built-in attribute imported here
+  --> $DIR/cross-crate.rs:5:5
+   |
+LL | use cross_crate::*;
+   |     ^^^^^^^^^^^^^^
+
+error: cannot use a tool module through an import
+  --> $DIR/cross-crate.rs:8:3
+   |
+LL | #[tool_mod::skip] //~ ERROR cannot use a tool module through an import
+   |   ^^^^^^^^
+   |
+note: the tool module imported here
+  --> $DIR/cross-crate.rs:5:5
+   |
+LL | use cross_crate::*;
+   |     ^^^^^^^^^^^^^^
+
+error: aborting due to 2 previous errors
+

From f690821d58650358f536606722a8f5531c8a6b84 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Esteban=20K=C3=BCber?= <esteban@kuber.com.ar>
Date: Fri, 8 Mar 2019 13:29:27 -0800
Subject: [PATCH 17/22] review comments

---
 src/libsyntax/parse/lexer/mod.rs           | 8 ++++----
 src/test/ui/parser/numeric-lifetime.rs     | 4 ++--
 src/test/ui/parser/numeric-lifetime.stderr | 4 ++--
 3 files changed, 8 insertions(+), 8 deletions(-)

diff --git a/src/libsyntax/parse/lexer/mod.rs b/src/libsyntax/parse/lexer/mod.rs
index f45f5e65312c2..6d2256474a3df 100644
--- a/src/libsyntax/parse/lexer/mod.rs
+++ b/src/libsyntax/parse/lexer/mod.rs
@@ -1451,11 +1451,10 @@ impl<'a> StringReader<'a> {
                         self.err_span_(
                             start_with_quote,
                             self.pos,
-                            "lifetimes can't start with a number",
+                            "lifetimes cannot start with a number",
                         );
                     }
 
-
                     return Ok(token::Lifetime(ident));
                 }
 
@@ -1892,7 +1891,7 @@ fn ident_start(c: Option<char>) -> bool {
         None => return false,
     };
 
-    (c.is_alphabetic() || c == '_' || (c > '\x7f' && c.is_xid_start()))
+    (c >= 'a' && c <= 'z') || (c >= 'A' && c <= 'Z') || c == '_' || (c > '\x7f' && c.is_xid_start())
 }
 
 fn ident_continue(c: Option<char>) -> bool {
@@ -1901,7 +1900,8 @@ fn ident_continue(c: Option<char>) -> bool {
         None => return false,
     };
 
-    (c.is_alphabetic() || c.is_numeric() || c == '_' || (c > '\x7f' && c.is_xid_continue()))
+    (c >= 'a' && c <= 'z') || (c >= 'A' && c <= 'Z') || (c >= '0' && c <= '9') || c == '_' ||
+    (c > '\x7f' && c.is_xid_continue())
 }
 
 #[inline]
diff --git a/src/test/ui/parser/numeric-lifetime.rs b/src/test/ui/parser/numeric-lifetime.rs
index 3483975a3cb8e..2d82354c62cca 100644
--- a/src/test/ui/parser/numeric-lifetime.rs
+++ b/src/test/ui/parser/numeric-lifetime.rs
@@ -1,6 +1,6 @@
 struct S<'1> { s: &'1 usize }
-//~^ ERROR lifetimes can't start with a number
-//~| ERROR lifetimes can't start with a number
+//~^ ERROR lifetimes cannot start with a number
+//~| ERROR lifetimes cannot start with a number
 fn main() {
     // verify that the parse error doesn't stop type checking
     let x: usize = "";
diff --git a/src/test/ui/parser/numeric-lifetime.stderr b/src/test/ui/parser/numeric-lifetime.stderr
index 1bbc508d57d4b..4018b24aac175 100644
--- a/src/test/ui/parser/numeric-lifetime.stderr
+++ b/src/test/ui/parser/numeric-lifetime.stderr
@@ -1,10 +1,10 @@
-error: lifetimes can't start with a number
+error: lifetimes cannot start with a number
   --> $DIR/numeric-lifetime.rs:1:10
    |
 LL | struct S<'1> { s: &'1 usize }
    |          ^^
 
-error: lifetimes can't start with a number
+error: lifetimes cannot start with a number
   --> $DIR/numeric-lifetime.rs:1:20
    |
 LL | struct S<'1> { s: &'1 usize }

From 3a83cb2c9ba2acca0577a5f4a092d7fc5b243faf Mon Sep 17 00:00:00 2001
From: Dan Robertson <dan@dlrobertson.com>
Date: Sat, 9 Mar 2019 03:39:23 +0000
Subject: [PATCH 18/22] Fix ICE in MIR pretty printing

A `Def::Variant` should be considered as a function in mir pretty
printing. Each variant has a constructor that we must print.

Given the following enum definition:

```
pub enum TestMe {
    X(usize),
}
```

We will need to generate a constructor for the variant `X` with a
signature that looks something like the following:

```
fn TestMe::X(_1: usize) -> TestMe;
```
---
 src/librustc_mir/util/pretty.rs        |  4 +++-
 src/test/mir-opt/unusual-item-types.rs | 18 ++++++++++++++++++
 2 files changed, 21 insertions(+), 1 deletion(-)

diff --git a/src/librustc_mir/util/pretty.rs b/src/librustc_mir/util/pretty.rs
index c3fbee3a2a6e5..af49f61ae86c7 100644
--- a/src/librustc_mir/util/pretty.rs
+++ b/src/librustc_mir/util/pretty.rs
@@ -1,4 +1,5 @@
 use rustc::hir::def_id::{DefId, LOCAL_CRATE};
+use rustc::hir::def::CtorKind;
 use rustc::mir::*;
 use rustc::mir::visit::Visitor;
 use rustc::ty::{self, TyCtxt};
@@ -597,7 +598,8 @@ fn write_mir_sig(
     trace!("write_mir_sig: {:?}", src.instance);
     let descr = tcx.describe_def(src.def_id());
     let is_function = match descr {
-        Some(Def::Fn(_)) | Some(Def::Method(_)) | Some(Def::StructCtor(..)) => true,
+        Some(Def::Fn(_)) | Some(Def::Method(_)) | Some(Def::Variant(..)) |
+        Some(Def::StructCtor(_, CtorKind::Fn)) => true,
         _ => tcx.is_closure(src.def_id()),
     };
     match (descr, src.promoted) {
diff --git a/src/test/mir-opt/unusual-item-types.rs b/src/test/mir-opt/unusual-item-types.rs
index fe85baa048e39..ced30381fda68 100644
--- a/src/test/mir-opt/unusual-item-types.rs
+++ b/src/test/mir-opt/unusual-item-types.rs
@@ -7,11 +7,18 @@ impl A {
     const ASSOCIATED_CONSTANT: i32 = 2;
 }
 
+// See #59021
+enum Test {
+    X(usize),
+    Y { a: usize },
+}
+
 enum E {
     V = 5,
 }
 
 fn main() {
+    let f = Test::X as fn(usize) -> Test;
     let v = Vec::<i32>::new();
 }
 
@@ -64,3 +71,14 @@ fn main() {
 //     _3 = const std::ops::Drop::drop(move _2) -> [return: bb6, unwind: bb5];
 // }
 // END rustc.ptr-real_drop_in_place.std__vec__Vec_i32_.AddMovesForPackedDrops.before.mir
+
+// START rustc.Test-X.mir_map.0.mir
+// fn Test::X(_1: usize) -> Test {
+//     let mut _0: Test;
+//
+//     bb0: {
+//         _0 = Test::X(move _1,);
+//         return;
+//     }
+// }
+// END rustc.Test-X.mir_map.0.mir

From df4ea90b39c808e858e05f3b4bb05fc29f812d26 Mon Sep 17 00:00:00 2001
From: Scott McMurray <scottmcm@users.noreply.github.com>
Date: Sat, 9 Mar 2019 19:10:28 -0800
Subject: [PATCH 19/22] Use lifetime contravariance to elide more lifetimes in
 core+alloc+std

---
 src/liballoc/boxed.rs                |  8 ++---
 src/liballoc/rc.rs                   |  4 +--
 src/liballoc/string.rs               |  4 +--
 src/liballoc/vec.rs                  | 16 +++++-----
 src/libcore/array.rs                 |  2 +-
 src/libcore/cmp.rs                   | 48 ++++++++++++++--------------
 src/libcore/internal_macros.rs       | 12 +++----
 src/libcore/ptr.rs                   | 16 +++++-----
 src/libstd/collections/hash/set.rs   |  8 ++---
 src/libstd/error.rs                  |  8 ++---
 src/libstd/ffi/c_str.rs              | 12 +++----
 src/libstd/ffi/os_str.rs             | 16 +++++-----
 src/libstd/path.rs                   | 12 +++----
 src/libstd/sys/cloudabi/shims/net.rs |  4 +--
 src/libstd/sys/redox/net/mod.rs      |  2 +-
 src/libstd/sys/sgx/net.rs            |  4 +--
 src/libstd/sys/unix/l4re.rs          |  4 +--
 src/libstd/sys/wasm/net.rs           |  4 +--
 src/libstd/sys_common/net.rs         |  2 +-
 19 files changed, 93 insertions(+), 93 deletions(-)

diff --git a/src/liballoc/boxed.rs b/src/liballoc/boxed.rs
index 74325a69e15ef..9bce142b483f2 100644
--- a/src/liballoc/boxed.rs
+++ b/src/liballoc/boxed.rs
@@ -489,7 +489,7 @@ impl<T: ?Sized> From<Box<T>> for Pin<Box<T>> {
 }
 
 #[stable(feature = "box_from_slice", since = "1.17.0")]
-impl<'a, T: Copy> From<&'a [T]> for Box<[T]> {
+impl<T: Copy> From<&[T]> for Box<[T]> {
     /// Converts a `&[T]` into a `Box<[T]>`
     ///
     /// This conversion allocates on the heap
@@ -503,7 +503,7 @@ impl<'a, T: Copy> From<&'a [T]> for Box<[T]> {
     ///
     /// println!("{:?}", boxed_slice);
     /// ```
-    fn from(slice: &'a [T]) -> Box<[T]> {
+    fn from(slice: &[T]) -> Box<[T]> {
         let mut boxed = unsafe { RawVec::with_capacity(slice.len()).into_box() };
         boxed.copy_from_slice(slice);
         boxed
@@ -511,7 +511,7 @@ impl<'a, T: Copy> From<&'a [T]> for Box<[T]> {
 }
 
 #[stable(feature = "box_from_slice", since = "1.17.0")]
-impl<'a> From<&'a str> for Box<str> {
+impl From<&str> for Box<str> {
     /// Converts a `&str` into a `Box<str>`
     ///
     /// This conversion allocates on the heap
@@ -523,7 +523,7 @@ impl<'a> From<&'a str> for Box<str> {
     /// println!("{}", boxed);
     /// ```
     #[inline]
-    fn from(s: &'a str) -> Box<str> {
+    fn from(s: &str) -> Box<str> {
         unsafe { from_boxed_utf8_unchecked(Box::from(s.as_bytes())) }
     }
 }
diff --git a/src/liballoc/rc.rs b/src/liballoc/rc.rs
index 12f75d84211e6..68eecd97ea11a 100644
--- a/src/liballoc/rc.rs
+++ b/src/liballoc/rc.rs
@@ -1145,7 +1145,7 @@ impl<T> From<T> for Rc<T> {
 }
 
 #[stable(feature = "shared_from_slice", since = "1.21.0")]
-impl<'a, T: Clone> From<&'a [T]> for Rc<[T]> {
+impl<T: Clone> From<&[T]> for Rc<[T]> {
     #[inline]
     fn from(v: &[T]) -> Rc<[T]> {
         <Self as RcFromSlice<T>>::from_slice(v)
@@ -1153,7 +1153,7 @@ impl<'a, T: Clone> From<&'a [T]> for Rc<[T]> {
 }
 
 #[stable(feature = "shared_from_slice", since = "1.21.0")]
-impl<'a> From<&'a str> for Rc<str> {
+impl From<&str> for Rc<str> {
     #[inline]
     fn from(v: &str) -> Rc<str> {
         let rc = Rc::<[u8]>::from(v.as_bytes());
diff --git a/src/liballoc/string.rs b/src/liballoc/string.rs
index b714df5d36b6a..a3e2098695f70 100644
--- a/src/liballoc/string.rs
+++ b/src/liballoc/string.rs
@@ -2172,9 +2172,9 @@ impl AsRef<[u8]> for String {
 }
 
 #[stable(feature = "rust1", since = "1.0.0")]
-impl<'a> From<&'a str> for String {
+impl From<&str> for String {
     #[inline]
-    fn from(s: &'a str) -> String {
+    fn from(s: &str) -> String {
         s.to_owned()
     }
 }
diff --git a/src/liballoc/vec.rs b/src/liballoc/vec.rs
index adcd3d84f4832..cd62c3e05244c 100644
--- a/src/liballoc/vec.rs
+++ b/src/liballoc/vec.rs
@@ -2182,25 +2182,25 @@ impl<T> AsMut<[T]> for Vec<T> {
 }
 
 #[stable(feature = "rust1", since = "1.0.0")]
-impl<'a, T: Clone> From<&'a [T]> for Vec<T> {
+impl<T: Clone> From<&[T]> for Vec<T> {
     #[cfg(not(test))]
-    fn from(s: &'a [T]) -> Vec<T> {
+    fn from(s: &[T]) -> Vec<T> {
         s.to_vec()
     }
     #[cfg(test)]
-    fn from(s: &'a [T]) -> Vec<T> {
+    fn from(s: &[T]) -> Vec<T> {
         crate::slice::to_vec(s)
     }
 }
 
 #[stable(feature = "vec_from_mut", since = "1.19.0")]
-impl<'a, T: Clone> From<&'a mut [T]> for Vec<T> {
+impl<T: Clone> From<&mut [T]> for Vec<T> {
     #[cfg(not(test))]
-    fn from(s: &'a mut [T]) -> Vec<T> {
+    fn from(s: &mut [T]) -> Vec<T> {
         s.to_vec()
     }
     #[cfg(test)]
-    fn from(s: &'a mut [T]) -> Vec<T> {
+    fn from(s: &mut [T]) -> Vec<T> {
         crate::slice::to_vec(s)
     }
 }
@@ -2231,8 +2231,8 @@ impl<T> From<Vec<T>> for Box<[T]> {
 }
 
 #[stable(feature = "rust1", since = "1.0.0")]
-impl<'a> From<&'a str> for Vec<u8> {
-    fn from(s: &'a str) -> Vec<u8> {
+impl From<&str> for Vec<u8> {
+    fn from(s: &str) -> Vec<u8> {
         From::from(s.as_bytes())
     }
 }
diff --git a/src/libcore/array.rs b/src/libcore/array.rs
index 9c6ecc4350246..dcd9ce6dad756 100644
--- a/src/libcore/array.rs
+++ b/src/libcore/array.rs
@@ -139,7 +139,7 @@ macro_rules! array_impls {
             }
 
             #[stable(feature = "try_from", since = "1.34.0")]
-            impl<'a, T> TryFrom<&'a [T]> for [T; $N] where T: Copy {
+            impl<T> TryFrom<&[T]> for [T; $N] where T: Copy {
                 type Error = TryFromSliceError;
 
                 fn try_from(slice: &[T]) -> Result<[T; $N], TryFromSliceError> {
diff --git a/src/libcore/cmp.rs b/src/libcore/cmp.rs
index 81fcdeee12d29..94bed3708369a 100644
--- a/src/libcore/cmp.rs
+++ b/src/libcore/cmp.rs
@@ -1004,26 +1004,26 @@ mod impls {
     // & pointers
 
     #[stable(feature = "rust1", since = "1.0.0")]
-    impl<'a, 'b, A: ?Sized, B: ?Sized> PartialEq<&'b B> for &'a A where A: PartialEq<B> {
+    impl<A: ?Sized, B: ?Sized> PartialEq<&B> for &A where A: PartialEq<B> {
         #[inline]
-        fn eq(&self, other: & &'b B) -> bool { PartialEq::eq(*self, *other) }
+        fn eq(&self, other: & &B) -> bool { PartialEq::eq(*self, *other) }
         #[inline]
-        fn ne(&self, other: & &'b B) -> bool { PartialEq::ne(*self, *other) }
+        fn ne(&self, other: & &B) -> bool { PartialEq::ne(*self, *other) }
     }
     #[stable(feature = "rust1", since = "1.0.0")]
-    impl<'a, 'b, A: ?Sized, B: ?Sized> PartialOrd<&'b B> for &'a A where A: PartialOrd<B> {
+    impl<A: ?Sized, B: ?Sized> PartialOrd<&B> for &A where A: PartialOrd<B> {
         #[inline]
-        fn partial_cmp(&self, other: &&'b B) -> Option<Ordering> {
+        fn partial_cmp(&self, other: &&B) -> Option<Ordering> {
             PartialOrd::partial_cmp(*self, *other)
         }
         #[inline]
-        fn lt(&self, other: & &'b B) -> bool { PartialOrd::lt(*self, *other) }
+        fn lt(&self, other: & &B) -> bool { PartialOrd::lt(*self, *other) }
         #[inline]
-        fn le(&self, other: & &'b B) -> bool { PartialOrd::le(*self, *other) }
+        fn le(&self, other: & &B) -> bool { PartialOrd::le(*self, *other) }
         #[inline]
-        fn ge(&self, other: & &'b B) -> bool { PartialOrd::ge(*self, *other) }
+        fn ge(&self, other: & &B) -> bool { PartialOrd::ge(*self, *other) }
         #[inline]
-        fn gt(&self, other: & &'b B) -> bool { PartialOrd::gt(*self, *other) }
+        fn gt(&self, other: & &B) -> bool { PartialOrd::gt(*self, *other) }
     }
     #[stable(feature = "rust1", since = "1.0.0")]
     impl<A: ?Sized> Ord for &A where A: Ord {
@@ -1036,26 +1036,26 @@ mod impls {
     // &mut pointers
 
     #[stable(feature = "rust1", since = "1.0.0")]
-    impl<'a, 'b, A: ?Sized, B: ?Sized> PartialEq<&'b mut B> for &'a mut A where A: PartialEq<B> {
+    impl<A: ?Sized, B: ?Sized> PartialEq<&mut B> for &mut A where A: PartialEq<B> {
         #[inline]
-        fn eq(&self, other: &&'b mut B) -> bool { PartialEq::eq(*self, *other) }
+        fn eq(&self, other: &&mut B) -> bool { PartialEq::eq(*self, *other) }
         #[inline]
-        fn ne(&self, other: &&'b mut B) -> bool { PartialEq::ne(*self, *other) }
+        fn ne(&self, other: &&mut B) -> bool { PartialEq::ne(*self, *other) }
     }
     #[stable(feature = "rust1", since = "1.0.0")]
-    impl<'a, 'b, A: ?Sized, B: ?Sized> PartialOrd<&'b mut B> for &'a mut A where A: PartialOrd<B> {
+    impl<A: ?Sized, B: ?Sized> PartialOrd<&mut B> for &mut A where A: PartialOrd<B> {
         #[inline]
-        fn partial_cmp(&self, other: &&'b mut B) -> Option<Ordering> {
+        fn partial_cmp(&self, other: &&mut B) -> Option<Ordering> {
             PartialOrd::partial_cmp(*self, *other)
         }
         #[inline]
-        fn lt(&self, other: &&'b mut B) -> bool { PartialOrd::lt(*self, *other) }
+        fn lt(&self, other: &&mut B) -> bool { PartialOrd::lt(*self, *other) }
         #[inline]
-        fn le(&self, other: &&'b mut B) -> bool { PartialOrd::le(*self, *other) }
+        fn le(&self, other: &&mut B) -> bool { PartialOrd::le(*self, *other) }
         #[inline]
-        fn ge(&self, other: &&'b mut B) -> bool { PartialOrd::ge(*self, *other) }
+        fn ge(&self, other: &&mut B) -> bool { PartialOrd::ge(*self, *other) }
         #[inline]
-        fn gt(&self, other: &&'b mut B) -> bool { PartialOrd::gt(*self, *other) }
+        fn gt(&self, other: &&mut B) -> bool { PartialOrd::gt(*self, *other) }
     }
     #[stable(feature = "rust1", since = "1.0.0")]
     impl<A: ?Sized> Ord for &mut A where A: Ord {
@@ -1066,18 +1066,18 @@ mod impls {
     impl<A: ?Sized> Eq for &mut A where A: Eq {}
 
     #[stable(feature = "rust1", since = "1.0.0")]
-    impl<'a, 'b, A: ?Sized, B: ?Sized> PartialEq<&'b mut B> for &'a A where A: PartialEq<B> {
+    impl<A: ?Sized, B: ?Sized> PartialEq<&mut B> for &A where A: PartialEq<B> {
         #[inline]
-        fn eq(&self, other: &&'b mut B) -> bool { PartialEq::eq(*self, *other) }
+        fn eq(&self, other: &&mut B) -> bool { PartialEq::eq(*self, *other) }
         #[inline]
-        fn ne(&self, other: &&'b mut B) -> bool { PartialEq::ne(*self, *other) }
+        fn ne(&self, other: &&mut B) -> bool { PartialEq::ne(*self, *other) }
     }
 
     #[stable(feature = "rust1", since = "1.0.0")]
-    impl<'a, 'b, A: ?Sized, B: ?Sized> PartialEq<&'b B> for &'a mut A where A: PartialEq<B> {
+    impl<A: ?Sized, B: ?Sized> PartialEq<&B> for &mut A where A: PartialEq<B> {
         #[inline]
-        fn eq(&self, other: &&'b B) -> bool { PartialEq::eq(*self, *other) }
+        fn eq(&self, other: &&B) -> bool { PartialEq::eq(*self, *other) }
         #[inline]
-        fn ne(&self, other: &&'b B) -> bool { PartialEq::ne(*self, *other) }
+        fn ne(&self, other: &&B) -> bool { PartialEq::ne(*self, *other) }
     }
 }
diff --git a/src/libcore/internal_macros.rs b/src/libcore/internal_macros.rs
index faca785e488c3..b5c20582986b2 100644
--- a/src/libcore/internal_macros.rs
+++ b/src/libcore/internal_macros.rs
@@ -37,21 +37,21 @@ macro_rules! forward_ref_binop {
         }
 
         #[$attr]
-        impl<'a> $imp<&'a $u> for $t {
+        impl $imp<&$u> for $t {
             type Output = <$t as $imp<$u>>::Output;
 
             #[inline]
-            fn $method(self, other: &'a $u) -> <$t as $imp<$u>>::Output {
+            fn $method(self, other: &$u) -> <$t as $imp<$u>>::Output {
                 $imp::$method(self, *other)
             }
         }
 
         #[$attr]
-        impl<'a, 'b> $imp<&'a $u> for &'b $t {
+        impl $imp<&$u> for &$t {
             type Output = <$t as $imp<$u>>::Output;
 
             #[inline]
-            fn $method(self, other: &'a $u) -> <$t as $imp<$u>>::Output {
+            fn $method(self, other: &$u) -> <$t as $imp<$u>>::Output {
                 $imp::$method(*self, *other)
             }
         }
@@ -67,9 +67,9 @@ macro_rules! forward_ref_op_assign {
     };
     (impl $imp:ident, $method:ident for $t:ty, $u:ty, #[$attr:meta]) => {
         #[$attr]
-        impl<'a> $imp<&'a $u> for $t {
+        impl $imp<&$u> for $t {
             #[inline]
-            fn $method(&mut self, other: &'a $u) {
+            fn $method(&mut self, other: &$u) {
                 $imp::$method(self, *other);
             }
         }
diff --git a/src/libcore/ptr.rs b/src/libcore/ptr.rs
index 53d4197603068..d288ca449dff3 100644
--- a/src/libcore/ptr.rs
+++ b/src/libcore/ptr.rs
@@ -2837,15 +2837,15 @@ impl<T: ?Sized> fmt::Pointer for Unique<T> {
 }
 
 #[unstable(feature = "ptr_internals", issue = "0")]
-impl<'a, T: ?Sized> From<&'a mut T> for Unique<T> {
-    fn from(reference: &'a mut T) -> Self {
+impl<T: ?Sized> From<&mut T> for Unique<T> {
+    fn from(reference: &mut T) -> Self {
         unsafe { Unique { pointer: reference as *mut T, _marker: PhantomData } }
     }
 }
 
 #[unstable(feature = "ptr_internals", issue = "0")]
-impl<'a, T: ?Sized> From<&'a T> for Unique<T> {
-    fn from(reference: &'a T) -> Self {
+impl<T: ?Sized> From<&T> for Unique<T> {
+    fn from(reference: &T) -> Self {
         unsafe { Unique { pointer: reference as *const T, _marker: PhantomData } }
     }
 }
@@ -3049,17 +3049,17 @@ impl<T: ?Sized> From<Unique<T>> for NonNull<T> {
 }
 
 #[stable(feature = "nonnull", since = "1.25.0")]
-impl<'a, T: ?Sized> From<&'a mut T> for NonNull<T> {
+impl<T: ?Sized> From<&mut T> for NonNull<T> {
     #[inline]
-    fn from(reference: &'a mut T) -> Self {
+    fn from(reference: &mut T) -> Self {
         unsafe { NonNull { pointer: reference as *mut T } }
     }
 }
 
 #[stable(feature = "nonnull", since = "1.25.0")]
-impl<'a, T: ?Sized> From<&'a T> for NonNull<T> {
+impl<T: ?Sized> From<&T> for NonNull<T> {
     #[inline]
-    fn from(reference: &'a T) -> Self {
+    fn from(reference: &T) -> Self {
         unsafe { NonNull { pointer: reference as *const T } }
     }
 }
diff --git a/src/libstd/collections/hash/set.rs b/src/libstd/collections/hash/set.rs
index 8a599c11b2095..f2111f2d9e028 100644
--- a/src/libstd/collections/hash/set.rs
+++ b/src/libstd/collections/hash/set.rs
@@ -850,7 +850,7 @@ impl<T, S> Default for HashSet<T, S>
 }
 
 #[stable(feature = "rust1", since = "1.0.0")]
-impl<'a, 'b, T, S> BitOr<&'b HashSet<T, S>> for &'a HashSet<T, S>
+impl<T, S> BitOr<&HashSet<T, S>> for &HashSet<T, S>
     where T: Eq + Hash + Clone,
           S: BuildHasher + Default
 {
@@ -882,7 +882,7 @@ impl<'a, 'b, T, S> BitOr<&'b HashSet<T, S>> for &'a HashSet<T, S>
 }
 
 #[stable(feature = "rust1", since = "1.0.0")]
-impl<'a, 'b, T, S> BitAnd<&'b HashSet<T, S>> for &'a HashSet<T, S>
+impl<T, S> BitAnd<&HashSet<T, S>> for &HashSet<T, S>
     where T: Eq + Hash + Clone,
           S: BuildHasher + Default
 {
@@ -914,7 +914,7 @@ impl<'a, 'b, T, S> BitAnd<&'b HashSet<T, S>> for &'a HashSet<T, S>
 }
 
 #[stable(feature = "rust1", since = "1.0.0")]
-impl<'a, 'b, T, S> BitXor<&'b HashSet<T, S>> for &'a HashSet<T, S>
+impl<T, S> BitXor<&HashSet<T, S>> for &HashSet<T, S>
     where T: Eq + Hash + Clone,
           S: BuildHasher + Default
 {
@@ -946,7 +946,7 @@ impl<'a, 'b, T, S> BitXor<&'b HashSet<T, S>> for &'a HashSet<T, S>
 }
 
 #[stable(feature = "rust1", since = "1.0.0")]
-impl<'a, 'b, T, S> Sub<&'b HashSet<T, S>> for &'a HashSet<T, S>
+impl<T, S> Sub<&HashSet<T, S>> for &HashSet<T, S>
     where T: Eq + Hash + Clone,
           S: BuildHasher + Default
 {
diff --git a/src/libstd/error.rs b/src/libstd/error.rs
index 2858308e8f8d5..3eb289501cb0f 100644
--- a/src/libstd/error.rs
+++ b/src/libstd/error.rs
@@ -337,7 +337,7 @@ impl From<String> for Box<dyn Error> {
 }
 
 #[stable(feature = "rust1", since = "1.0.0")]
-impl<'a, 'b> From<&'b str> for Box<dyn Error + Send + Sync + 'a> {
+impl<'a> From<&str> for Box<dyn Error + Send + Sync + 'a> {
     /// Converts a [`str`] into a box of dyn [`Error`] + [`Send`] + [`Sync`].
     ///
     /// # Examples
@@ -351,13 +351,13 @@ impl<'a, 'b> From<&'b str> for Box<dyn Error + Send + Sync + 'a> {
     /// assert!(
     ///     mem::size_of::<Box<dyn Error + Send + Sync>>() == mem::size_of_val(&a_boxed_error))
     /// ```
-    fn from(err: &'b str) -> Box<dyn Error + Send + Sync + 'a> {
+    fn from(err: &str) -> Box<dyn Error + Send + Sync + 'a> {
         From::from(String::from(err))
     }
 }
 
 #[stable(feature = "string_box_error", since = "1.6.0")]
-impl<'a> From<&'a str> for Box<dyn Error> {
+impl From<&str> for Box<dyn Error> {
     /// Converts a [`str`] into a box of dyn [`Error`].
     ///
     /// # Examples
@@ -370,7 +370,7 @@ impl<'a> From<&'a str> for Box<dyn Error> {
     /// let a_boxed_error = Box::<Error>::from(a_str_error);
     /// assert!(mem::size_of::<Box<dyn Error>>() == mem::size_of_val(&a_boxed_error))
     /// ```
-    fn from(err: &'a str) -> Box<dyn Error> {
+    fn from(err: &str) -> Box<dyn Error> {
         From::from(String::from(err))
     }
 }
diff --git a/src/libstd/ffi/c_str.rs b/src/libstd/ffi/c_str.rs
index 139680e526fd6..ad3f45bfadaf4 100644
--- a/src/libstd/ffi/c_str.rs
+++ b/src/libstd/ffi/c_str.rs
@@ -690,8 +690,8 @@ impl<'a> From<Cow<'a, CStr>> for CString {
 }
 
 #[stable(feature = "box_from_c_str", since = "1.17.0")]
-impl<'a> From<&'a CStr> for Box<CStr> {
-    fn from(s: &'a CStr) -> Box<CStr> {
+impl From<&CStr> for Box<CStr> {
+    fn from(s: &CStr) -> Box<CStr> {
         let boxed: Box<[u8]> = Box::from(s.to_bytes_with_nul());
         unsafe { Box::from_raw(Box::into_raw(boxed) as *mut CStr) }
     }
@@ -767,7 +767,7 @@ impl From<CString> for Arc<CStr> {
 }
 
 #[stable(feature = "shared_from_slice2", since = "1.24.0")]
-impl<'a> From<&'a CStr> for Arc<CStr> {
+impl From<&CStr> for Arc<CStr> {
     #[inline]
     fn from(s: &CStr) -> Arc<CStr> {
         let arc: Arc<[u8]> = Arc::from(s.to_bytes_with_nul());
@@ -789,7 +789,7 @@ impl From<CString> for Rc<CStr> {
 }
 
 #[stable(feature = "shared_from_slice2", since = "1.24.0")]
-impl<'a> From<&'a CStr> for Rc<CStr> {
+impl From<&CStr> for Rc<CStr> {
     #[inline]
     fn from(s: &CStr) -> Rc<CStr> {
         let rc: Rc<[u8]> = Rc::from(s.to_bytes_with_nul());
@@ -1268,8 +1268,8 @@ impl ToOwned for CStr {
 }
 
 #[stable(feature = "cstring_asref", since = "1.7.0")]
-impl<'a> From<&'a CStr> for CString {
-    fn from(s: &'a CStr) -> CString {
+impl From<&CStr> for CString {
+    fn from(s: &CStr) -> CString {
         s.to_owned()
     }
 }
diff --git a/src/libstd/ffi/os_str.rs b/src/libstd/ffi/os_str.rs
index f68eaeb9c7e1f..3a0590021c917 100644
--- a/src/libstd/ffi/os_str.rs
+++ b/src/libstd/ffi/os_str.rs
@@ -357,8 +357,8 @@ impl From<String> for OsString {
 }
 
 #[stable(feature = "rust1", since = "1.0.0")]
-impl<'a, T: ?Sized + AsRef<OsStr>> From<&'a T> for OsString {
-    fn from(s: &'a T) -> OsString {
+impl<T: ?Sized + AsRef<OsStr>> From<&T> for OsString {
+    fn from(s: &T) -> OsString {
         s.as_ref().to_os_string()
     }
 }
@@ -421,8 +421,8 @@ impl PartialEq<OsString> for str {
 }
 
 #[stable(feature = "os_str_str_ref_eq", since = "1.29.0")]
-impl<'a> PartialEq<&'a str> for OsString {
-    fn eq(&self, other: &&'a str) -> bool {
+impl PartialEq<&str> for OsString {
+    fn eq(&self, other: &&str) -> bool {
         **self == **other
     }
 }
@@ -656,8 +656,8 @@ impl OsStr {
 }
 
 #[stable(feature = "box_from_os_str", since = "1.17.0")]
-impl<'a> From<&'a OsStr> for Box<OsStr> {
-    fn from(s: &'a OsStr) -> Box<OsStr> {
+impl From<&OsStr> for Box<OsStr> {
+    fn from(s: &OsStr) -> Box<OsStr> {
         let rw = Box::into_raw(s.inner.into_box()) as *mut OsStr;
         unsafe { Box::from_raw(rw) }
     }
@@ -707,7 +707,7 @@ impl From<OsString> for Arc<OsStr> {
 }
 
 #[stable(feature = "shared_from_slice2", since = "1.24.0")]
-impl<'a> From<&'a OsStr> for Arc<OsStr> {
+impl From<&OsStr> for Arc<OsStr> {
     #[inline]
     fn from(s: &OsStr) -> Arc<OsStr> {
         let arc = s.inner.into_arc();
@@ -729,7 +729,7 @@ impl From<OsString> for Rc<OsStr> {
 }
 
 #[stable(feature = "shared_from_slice2", since = "1.24.0")]
-impl<'a> From<&'a OsStr> for Rc<OsStr> {
+impl From<&OsStr> for Rc<OsStr> {
     #[inline]
     fn from(s: &OsStr) -> Rc<OsStr> {
         let rc = s.inner.into_rc();
diff --git a/src/libstd/path.rs b/src/libstd/path.rs
index 858a5778b8161..ea3fcd8ce2859 100644
--- a/src/libstd/path.rs
+++ b/src/libstd/path.rs
@@ -1456,8 +1456,8 @@ impl PathBuf {
 }
 
 #[stable(feature = "box_from_path", since = "1.17.0")]
-impl<'a> From<&'a Path> for Box<Path> {
-    fn from(path: &'a Path) -> Box<Path> {
+impl From<&Path> for Box<Path> {
+    fn from(path: &Path) -> Box<Path> {
         let boxed: Box<OsStr> = path.inner.into();
         let rw = Box::into_raw(boxed) as *mut Path;
         unsafe { Box::from_raw(rw) }
@@ -1494,8 +1494,8 @@ impl Clone for Box<Path> {
 }
 
 #[stable(feature = "rust1", since = "1.0.0")]
-impl<'a, T: ?Sized + AsRef<OsStr>> From<&'a T> for PathBuf {
-    fn from(s: &'a T) -> PathBuf {
+impl<T: ?Sized + AsRef<OsStr>> From<&T> for PathBuf {
+    fn from(s: &T) -> PathBuf {
         PathBuf::from(s.as_ref().to_os_string())
     }
 }
@@ -1630,7 +1630,7 @@ impl From<PathBuf> for Arc<Path> {
 }
 
 #[stable(feature = "shared_from_slice2", since = "1.24.0")]
-impl<'a> From<&'a Path> for Arc<Path> {
+impl From<&Path> for Arc<Path> {
     /// Converts a Path into a Rc by copying the Path data into a new Rc buffer.
     #[inline]
     fn from(s: &Path) -> Arc<Path> {
@@ -1650,7 +1650,7 @@ impl From<PathBuf> for Rc<Path> {
 }
 
 #[stable(feature = "shared_from_slice2", since = "1.24.0")]
-impl<'a> From<&'a Path> for Rc<Path> {
+impl From<&Path> for Rc<Path> {
     /// Converts a Path into a Rc by copying the Path data into a new Rc buffer.
     #[inline]
     fn from(s: &Path) -> Rc<Path> {
diff --git a/src/libstd/sys/cloudabi/shims/net.rs b/src/libstd/sys/cloudabi/shims/net.rs
index 50d72dc7b240b..6d2a4962ab444 100644
--- a/src/libstd/sys/cloudabi/shims/net.rs
+++ b/src/libstd/sys/cloudabi/shims/net.rs
@@ -297,10 +297,10 @@ impl Iterator for LookupHost {
     }
 }
 
-impl<'a> TryFrom<&'a str> for LookupHost {
+impl TryFrom<&str> for LookupHost {
     type Error = io::Error;
 
-    fn try_from(_v: &'a str) -> io::Result<LookupHost> {
+    fn try_from(_v: &str) -> io::Result<LookupHost> {
         unsupported()
     }
 }
diff --git a/src/libstd/sys/redox/net/mod.rs b/src/libstd/sys/redox/net/mod.rs
index a172763f61313..dbaa140ed8a0f 100644
--- a/src/libstd/sys/redox/net/mod.rs
+++ b/src/libstd/sys/redox/net/mod.rs
@@ -35,7 +35,7 @@ impl Iterator for LookupHost {
     }
 }
 
-impl<'a> TryFrom<&'a str> for LookupHost {
+impl TryFrom<&str> for LookupHost {
     type Error = io::Error;
 
     fn try_from(s: &str) -> io::Result<LookupHost> {
diff --git a/src/libstd/sys/sgx/net.rs b/src/libstd/sys/sgx/net.rs
index ab8b2681393f8..e5e42e3d0b048 100644
--- a/src/libstd/sys/sgx/net.rs
+++ b/src/libstd/sys/sgx/net.rs
@@ -420,10 +420,10 @@ impl Iterator for LookupHost {
     }
 }
 
-impl<'a> TryFrom<&'a str> for LookupHost {
+impl TryFrom<&str> for LookupHost {
     type Error = io::Error;
 
-    fn try_from(v: &'a str) -> io::Result<LookupHost> {
+    fn try_from(v: &str) -> io::Result<LookupHost> {
         LookupHost::new(v.to_owned())
     }
 }
diff --git a/src/libstd/sys/unix/l4re.rs b/src/libstd/sys/unix/l4re.rs
index b6e8cc738946b..b9e725371a36e 100644
--- a/src/libstd/sys/unix/l4re.rs
+++ b/src/libstd/sys/unix/l4re.rs
@@ -447,10 +447,10 @@ pub mod net {
     unsafe impl Send for LookupHost {}
 
 
-    impl<'a> TryFrom<&'a str> for LookupHost {
+    impl TryFrom<&str> for LookupHost {
         type Error = io::Error;
 
-        fn try_from(_v: &'a str) -> io::Result<LookupHost> {
+        fn try_from(_v: &str) -> io::Result<LookupHost> {
             unimpl!();
         }
     }
diff --git a/src/libstd/sys/wasm/net.rs b/src/libstd/sys/wasm/net.rs
index 1249832fb09d2..a2ea2dfbbc032 100644
--- a/src/libstd/sys/wasm/net.rs
+++ b/src/libstd/sys/wasm/net.rs
@@ -298,10 +298,10 @@ impl Iterator for LookupHost {
     }
 }
 
-impl<'a> TryFrom<&'a str> for LookupHost {
+impl TryFrom<&str> for LookupHost {
     type Error = io::Error;
 
-    fn try_from(_v: &'a str) -> io::Result<LookupHost> {
+    fn try_from(_v: &str) -> io::Result<LookupHost> {
         unsupported()
     }
 }
diff --git a/src/libstd/sys_common/net.rs b/src/libstd/sys_common/net.rs
index 36721171b1733..b9505aaa69ba5 100644
--- a/src/libstd/sys_common/net.rs
+++ b/src/libstd/sys_common/net.rs
@@ -157,7 +157,7 @@ impl Drop for LookupHost {
     }
 }
 
-impl<'a> TryFrom<&'a str> for LookupHost {
+impl TryFrom<&str> for LookupHost {
     type Error = io::Error;
 
     fn try_from(s: &str) -> io::Result<LookupHost> {

From 4888b1fb99f1bf6a58bebaededdfbf4477383634 Mon Sep 17 00:00:00 2001
From: Ralf Jung <post@ralfj.de>
Date: Sun, 10 Mar 2019 17:45:45 +0100
Subject: [PATCH 20/22] we can now skip should_panic tests with the libtest
 harness

---
 src/liballoc/tests/binary_heap.rs |  2 +-
 src/liballoc/tests/btree/map.rs   |  5 -----
 src/liballoc/tests/slice.rs       | 18 ------------------
 src/liballoc/tests/str.rs         | 11 -----------
 src/liballoc/tests/string.rs      |  9 ---------
 src/liballoc/tests/vec.rs         | 12 ------------
 src/liballoc/tests/vec_deque.rs   |  1 -
 src/libcore/tests/cell.rs         |  3 ---
 src/libcore/tests/iter.rs         |  2 --
 src/libcore/tests/num/bignum.rs   | 14 --------------
 src/libcore/tests/option.rs       |  3 ---
 src/libcore/tests/result.rs       |  3 ---
 src/libcore/tests/slice.rs        |  7 -------
 src/libcore/tests/time.rs         |  2 --
 14 files changed, 1 insertion(+), 91 deletions(-)

diff --git a/src/liballoc/tests/binary_heap.rs b/src/liballoc/tests/binary_heap.rs
index 1d4a3edc1ac42..a97a790f5a2d8 100644
--- a/src/liballoc/tests/binary_heap.rs
+++ b/src/liballoc/tests/binary_heap.rs
@@ -282,7 +282,7 @@ fn assert_covariance() {
 //
 // Destructors must be called exactly once per element.
 #[test]
-#[cfg(not(miri))] // Miri does not support panics
+#[cfg(not(miri))] // Miri does not support entropy
 fn panic_safe() {
     static DROP_COUNTER: AtomicUsize = AtomicUsize::new(0);
 
diff --git a/src/liballoc/tests/btree/map.rs b/src/liballoc/tests/btree/map.rs
index f14750089c956..844afe870766b 100644
--- a/src/liballoc/tests/btree/map.rs
+++ b/src/liballoc/tests/btree/map.rs
@@ -226,7 +226,6 @@ fn test_range_equal_empty_cases() {
 
 #[test]
 #[should_panic]
-#[cfg(not(miri))] // Miri does not support panics
 fn test_range_equal_excluded() {
     let map: BTreeMap<_, _> = (0..5).map(|i| (i, i)).collect();
     map.range((Excluded(2), Excluded(2)));
@@ -234,7 +233,6 @@ fn test_range_equal_excluded() {
 
 #[test]
 #[should_panic]
-#[cfg(not(miri))] // Miri does not support panics
 fn test_range_backwards_1() {
     let map: BTreeMap<_, _> = (0..5).map(|i| (i, i)).collect();
     map.range((Included(3), Included(2)));
@@ -242,7 +240,6 @@ fn test_range_backwards_1() {
 
 #[test]
 #[should_panic]
-#[cfg(not(miri))] // Miri does not support panics
 fn test_range_backwards_2() {
     let map: BTreeMap<_, _> = (0..5).map(|i| (i, i)).collect();
     map.range((Included(3), Excluded(2)));
@@ -250,7 +247,6 @@ fn test_range_backwards_2() {
 
 #[test]
 #[should_panic]
-#[cfg(not(miri))] // Miri does not support panics
 fn test_range_backwards_3() {
     let map: BTreeMap<_, _> = (0..5).map(|i| (i, i)).collect();
     map.range((Excluded(3), Included(2)));
@@ -258,7 +254,6 @@ fn test_range_backwards_3() {
 
 #[test]
 #[should_panic]
-#[cfg(not(miri))] // Miri does not support panics
 fn test_range_backwards_4() {
     let map: BTreeMap<_, _> = (0..5).map(|i| (i, i)).collect();
     map.range((Excluded(3), Excluded(2)));
diff --git a/src/liballoc/tests/slice.rs b/src/liballoc/tests/slice.rs
index feba46b0fad78..fb99c95fc6842 100644
--- a/src/liballoc/tests/slice.rs
+++ b/src/liballoc/tests/slice.rs
@@ -258,7 +258,6 @@ fn test_swap_remove() {
 
 #[test]
 #[should_panic]
-#[cfg(not(miri))] // Miri does not support panics
 fn test_swap_remove_fail() {
     let mut v = vec![1];
     let _ = v.swap_remove(0);
@@ -632,7 +631,6 @@ fn test_insert() {
 
 #[test]
 #[should_panic]
-#[cfg(not(miri))] // Miri does not support panics
 fn test_insert_oob() {
     let mut a = vec![1, 2, 3];
     a.insert(4, 5);
@@ -657,7 +655,6 @@ fn test_remove() {
 
 #[test]
 #[should_panic]
-#[cfg(not(miri))] // Miri does not support panics
 fn test_remove_fail() {
     let mut a = vec![1];
     let _ = a.remove(0);
@@ -939,7 +936,6 @@ fn test_windowsator() {
 
 #[test]
 #[should_panic]
-#[cfg(not(miri))] // Miri does not support panics
 fn test_windowsator_0() {
     let v = &[1, 2, 3, 4];
     let _it = v.windows(0);
@@ -964,7 +960,6 @@ fn test_chunksator() {
 
 #[test]
 #[should_panic]
-#[cfg(not(miri))] // Miri does not support panics
 fn test_chunksator_0() {
     let v = &[1, 2, 3, 4];
     let _it = v.chunks(0);
@@ -989,7 +984,6 @@ fn test_chunks_exactator() {
 
 #[test]
 #[should_panic]
-#[cfg(not(miri))] // Miri does not support panics
 fn test_chunks_exactator_0() {
     let v = &[1, 2, 3, 4];
     let _it = v.chunks_exact(0);
@@ -1014,7 +1008,6 @@ fn test_rchunksator() {
 
 #[test]
 #[should_panic]
-#[cfg(not(miri))] // Miri does not support panics
 fn test_rchunksator_0() {
     let v = &[1, 2, 3, 4];
     let _it = v.rchunks(0);
@@ -1039,7 +1032,6 @@ fn test_rchunks_exactator() {
 
 #[test]
 #[should_panic]
-#[cfg(not(miri))] // Miri does not support panics
 fn test_rchunks_exactator_0() {
     let v = &[1, 2, 3, 4];
     let _it = v.rchunks_exact(0);
@@ -1092,7 +1084,6 @@ fn test_vec_default() {
 
 #[test]
 #[should_panic]
-#[cfg(not(miri))] // Miri does not support panics
 fn test_overflow_does_not_cause_segfault() {
     let mut v = vec![];
     v.reserve_exact(!0);
@@ -1102,7 +1093,6 @@ fn test_overflow_does_not_cause_segfault() {
 
 #[test]
 #[should_panic]
-#[cfg(not(miri))] // Miri does not support panics
 fn test_overflow_does_not_cause_segfault_managed() {
     let mut v = vec![Rc::new(1)];
     v.reserve_exact(!0);
@@ -1278,7 +1268,6 @@ fn test_mut_chunks_rev() {
 
 #[test]
 #[should_panic]
-#[cfg(not(miri))] // Miri does not support panics
 fn test_mut_chunks_0() {
     let mut v = [1, 2, 3, 4];
     let _it = v.chunks_mut(0);
@@ -1311,7 +1300,6 @@ fn test_mut_chunks_exact_rev() {
 
 #[test]
 #[should_panic]
-#[cfg(not(miri))] // Miri does not support panics
 fn test_mut_chunks_exact_0() {
     let mut v = [1, 2, 3, 4];
     let _it = v.chunks_exact_mut(0);
@@ -1344,7 +1332,6 @@ fn test_mut_rchunks_rev() {
 
 #[test]
 #[should_panic]
-#[cfg(not(miri))] // Miri does not support panics
 fn test_mut_rchunks_0() {
     let mut v = [1, 2, 3, 4];
     let _it = v.rchunks_mut(0);
@@ -1377,7 +1364,6 @@ fn test_mut_rchunks_exact_rev() {
 
 #[test]
 #[should_panic]
-#[cfg(not(miri))] // Miri does not support panics
 fn test_mut_rchunks_exact_0() {
     let mut v = [1, 2, 3, 4];
     let _it = v.rchunks_exact_mut(0);
@@ -1411,7 +1397,6 @@ fn test_box_slice_clone() {
 #[test]
 #[allow(unused_must_use)] // here, we care about the side effects of `.clone()`
 #[cfg_attr(target_os = "emscripten", ignore)]
-#[cfg(not(miri))] // Miri does not support panics
 fn test_box_slice_clone_panics() {
     use std::sync::Arc;
     use std::sync::atomic::{AtomicUsize, Ordering};
@@ -1476,7 +1461,6 @@ fn test_copy_from_slice() {
 
 #[test]
 #[should_panic(expected = "destination and source slices have different lengths")]
-#[cfg(not(miri))] // Miri does not support panics
 fn test_copy_from_slice_dst_longer() {
     let src = [0, 1, 2, 3];
     let mut dst = [0; 5];
@@ -1485,7 +1469,6 @@ fn test_copy_from_slice_dst_longer() {
 
 #[test]
 #[should_panic(expected = "destination and source slices have different lengths")]
-#[cfg(not(miri))] // Miri does not support panics
 fn test_copy_from_slice_dst_shorter() {
     let src = [0, 1, 2, 3];
     let mut dst = [0; 3];
@@ -1605,7 +1588,6 @@ thread_local!(static SILENCE_PANIC: Cell<bool> = Cell::new(false));
 
 #[test]
 #[cfg_attr(target_os = "emscripten", ignore)] // no threads
-#[cfg(not(miri))] // Miri does not support panics
 fn panic_safe() {
     let prev = panic::take_hook();
     panic::set_hook(Box::new(move |info| {
diff --git a/src/liballoc/tests/str.rs b/src/liballoc/tests/str.rs
index b33a564218888..f2dc19a42296a 100644
--- a/src/liballoc/tests/str.rs
+++ b/src/liballoc/tests/str.rs
@@ -351,7 +351,6 @@ mod slice_index {
     //  to be used in `should_panic`)
     #[test]
     #[should_panic(expected = "out of bounds")]
-    #[cfg(not(miri))] // Miri does not support panics
     fn assert_range_eq_can_fail_by_panic() {
         assert_range_eq!("abc", 0..5, "abc");
     }
@@ -361,7 +360,6 @@ mod slice_index {
     //  to be used in `should_panic`)
     #[test]
     #[should_panic(expected = "==")]
-    #[cfg(not(miri))] // Miri does not support panics
     fn assert_range_eq_can_fail_by_inequality() {
         assert_range_eq!("abc", 0..2, "abc");
     }
@@ -409,7 +407,6 @@ mod slice_index {
 
                 #[test]
                 #[should_panic(expected = $expect_msg)]
-                #[cfg(not(miri))] // Miri does not support panics
                 fn index_fail() {
                     let v: String = $data.into();
                     let v: &str = &v;
@@ -418,7 +415,6 @@ mod slice_index {
 
                 #[test]
                 #[should_panic(expected = $expect_msg)]
-                #[cfg(not(miri))] // Miri does not support panics
                 fn index_mut_fail() {
                     let mut v: String = $data.into();
                     let v: &mut str = &mut v;
@@ -514,7 +510,6 @@ mod slice_index {
 
     #[test]
     #[should_panic]
-    #[cfg(not(miri))] // Miri does not support panics
     fn test_slice_fail() {
         &"中华Việt Nam"[0..2];
     }
@@ -666,14 +661,12 @@ mod slice_index {
     // check the panic includes the prefix of the sliced string
     #[test]
     #[should_panic(expected="byte index 1024 is out of bounds of `Lorem ipsum dolor sit amet")]
-    #[cfg(not(miri))] // Miri does not support panics
     fn test_slice_fail_truncated_1() {
         &LOREM_PARAGRAPH[..1024];
     }
     // check the truncation in the panic message
     #[test]
     #[should_panic(expected="luctus, im`[...]")]
-    #[cfg(not(miri))] // Miri does not support panics
     fn test_slice_fail_truncated_2() {
         &LOREM_PARAGRAPH[..1024];
     }
@@ -688,7 +681,6 @@ fn test_str_slice_rangetoinclusive_ok() {
 
 #[test]
 #[should_panic]
-#[cfg(not(miri))] // Miri does not support panics
 fn test_str_slice_rangetoinclusive_notok() {
     let s = "abcαβγ";
     &s[..=3];
@@ -704,7 +696,6 @@ fn test_str_slicemut_rangetoinclusive_ok() {
 
 #[test]
 #[should_panic]
-#[cfg(not(miri))] // Miri does not support panics
 fn test_str_slicemut_rangetoinclusive_notok() {
     let mut s = "abcαβγ".to_owned();
     let s: &mut str = &mut s;
@@ -894,7 +885,6 @@ fn test_as_bytes() {
 
 #[test]
 #[should_panic]
-#[cfg(not(miri))] // Miri does not support panics
 fn test_as_bytes_fail() {
     // Don't double free. (I'm not sure if this exercises the
     // original problem code path anymore.)
@@ -984,7 +974,6 @@ fn test_split_at_mut() {
 
 #[test]
 #[should_panic]
-#[cfg(not(miri))] // Miri does not support panics
 fn test_split_at_boundscheck() {
     let s = "ศไทย中华Việt Nam";
     s.split_at(1);
diff --git a/src/liballoc/tests/string.rs b/src/liballoc/tests/string.rs
index 7e93d84fe3b97..7e75b8c4f28c8 100644
--- a/src/liballoc/tests/string.rs
+++ b/src/liballoc/tests/string.rs
@@ -231,7 +231,6 @@ fn test_split_off_empty() {
 
 #[test]
 #[should_panic]
-#[cfg(not(miri))] // Miri does not support panics
 fn test_split_off_past_end() {
     let orig = "Hello, world!";
     let mut split = String::from(orig);
@@ -240,7 +239,6 @@ fn test_split_off_past_end() {
 
 #[test]
 #[should_panic]
-#[cfg(not(miri))] // Miri does not support panics
 fn test_split_off_mid_char() {
     let mut orig = String::from("山");
     orig.split_off(1);
@@ -289,7 +287,6 @@ fn test_str_truncate_invalid_len() {
 
 #[test]
 #[should_panic]
-#[cfg(not(miri))] // Miri does not support panics
 fn test_str_truncate_split_codepoint() {
     let mut s = String::from("\u{FC}"); // ü
     s.truncate(1);
@@ -324,7 +321,6 @@ fn remove() {
 
 #[test]
 #[should_panic]
-#[cfg(not(miri))] // Miri does not support panics
 fn remove_bad() {
     "ศ".to_string().remove(1);
 }
@@ -360,13 +356,11 @@ fn insert() {
 
 #[test]
 #[should_panic]
-#[cfg(not(miri))] // Miri does not support panics
 fn insert_bad1() {
     "".to_string().insert(1, 't');
 }
 #[test]
 #[should_panic]
-#[cfg(not(miri))] // Miri does not support panics
 fn insert_bad2() {
     "ệ".to_string().insert(1, 't');
 }
@@ -447,7 +441,6 @@ fn test_replace_range() {
 
 #[test]
 #[should_panic]
-#[cfg(not(miri))] // Miri does not support panics
 fn test_replace_range_char_boundary() {
     let mut s = "Hello, 世界!".to_owned();
     s.replace_range(..8, "");
@@ -464,7 +457,6 @@ fn test_replace_range_inclusive_range() {
 
 #[test]
 #[should_panic]
-#[cfg(not(miri))] // Miri does not support panics
 fn test_replace_range_out_of_bounds() {
     let mut s = String::from("12345");
     s.replace_range(5..6, "789");
@@ -472,7 +464,6 @@ fn test_replace_range_out_of_bounds() {
 
 #[test]
 #[should_panic]
-#[cfg(not(miri))] // Miri does not support panics
 fn test_replace_range_inclusive_out_of_bounds() {
     let mut s = String::from("12345");
     s.replace_range(5..=5, "789");
diff --git a/src/liballoc/tests/vec.rs b/src/liballoc/tests/vec.rs
index 6e4ca1d90e642..545332bcd6a2f 100644
--- a/src/liballoc/tests/vec.rs
+++ b/src/liballoc/tests/vec.rs
@@ -368,7 +368,6 @@ fn test_vec_truncate_drop() {
 
 #[test]
 #[should_panic]
-#[cfg(not(miri))] // Miri does not support panics
 fn test_vec_truncate_fail() {
     struct BadElem(i32);
     impl Drop for BadElem {
@@ -392,7 +391,6 @@ fn test_index() {
 
 #[test]
 #[should_panic]
-#[cfg(not(miri))] // Miri does not support panics
 fn test_index_out_of_bounds() {
     let vec = vec![1, 2, 3];
     let _ = vec[3];
@@ -400,7 +398,6 @@ fn test_index_out_of_bounds() {
 
 #[test]
 #[should_panic]
-#[cfg(not(miri))] // Miri does not support panics
 fn test_slice_out_of_bounds_1() {
     let x = vec![1, 2, 3, 4, 5];
     &x[!0..];
@@ -408,7 +405,6 @@ fn test_slice_out_of_bounds_1() {
 
 #[test]
 #[should_panic]
-#[cfg(not(miri))] // Miri does not support panics
 fn test_slice_out_of_bounds_2() {
     let x = vec![1, 2, 3, 4, 5];
     &x[..6];
@@ -416,7 +412,6 @@ fn test_slice_out_of_bounds_2() {
 
 #[test]
 #[should_panic]
-#[cfg(not(miri))] // Miri does not support panics
 fn test_slice_out_of_bounds_3() {
     let x = vec![1, 2, 3, 4, 5];
     &x[!0..4];
@@ -424,7 +419,6 @@ fn test_slice_out_of_bounds_3() {
 
 #[test]
 #[should_panic]
-#[cfg(not(miri))] // Miri does not support panics
 fn test_slice_out_of_bounds_4() {
     let x = vec![1, 2, 3, 4, 5];
     &x[1..6];
@@ -432,7 +426,6 @@ fn test_slice_out_of_bounds_4() {
 
 #[test]
 #[should_panic]
-#[cfg(not(miri))] // Miri does not support panics
 fn test_slice_out_of_bounds_5() {
     let x = vec![1, 2, 3, 4, 5];
     &x[3..2];
@@ -440,7 +433,6 @@ fn test_slice_out_of_bounds_5() {
 
 #[test]
 #[should_panic]
-#[cfg(not(miri))] // Miri does not support panics
 fn test_swap_remove_empty() {
     let mut vec = Vec::<i32>::new();
     vec.swap_remove(0);
@@ -511,7 +503,6 @@ fn test_drain_items_zero_sized() {
 
 #[test]
 #[should_panic]
-#[cfg(not(miri))] // Miri does not support panics
 fn test_drain_out_of_bounds() {
     let mut v = vec![1, 2, 3, 4, 5];
     v.drain(5..6);
@@ -585,7 +576,6 @@ fn test_drain_max_vec_size() {
 
 #[test]
 #[should_panic]
-#[cfg(not(miri))] // Miri does not support panics
 fn test_drain_inclusive_out_of_bounds() {
     let mut v = vec![1, 2, 3, 4, 5];
     v.drain(5..=5);
@@ -615,7 +605,6 @@ fn test_splice_inclusive_range() {
 
 #[test]
 #[should_panic]
-#[cfg(not(miri))] // Miri does not support panics
 fn test_splice_out_of_bounds() {
     let mut v = vec![1, 2, 3, 4, 5];
     let a = [10, 11, 12];
@@ -624,7 +613,6 @@ fn test_splice_out_of_bounds() {
 
 #[test]
 #[should_panic]
-#[cfg(not(miri))] // Miri does not support panics
 fn test_splice_inclusive_out_of_bounds() {
     let mut v = vec![1, 2, 3, 4, 5];
     let a = [10, 11, 12];
diff --git a/src/liballoc/tests/vec_deque.rs b/src/liballoc/tests/vec_deque.rs
index 16ddc1444fcf9..e0fe10a55f55c 100644
--- a/src/liballoc/tests/vec_deque.rs
+++ b/src/liballoc/tests/vec_deque.rs
@@ -108,7 +108,6 @@ fn test_index() {
 
 #[test]
 #[should_panic]
-#[cfg(not(miri))] // Miri does not support panics
 fn test_index_out_of_bounds() {
     let mut deq = VecDeque::new();
     for i in 1..4 {
diff --git a/src/libcore/tests/cell.rs b/src/libcore/tests/cell.rs
index b16416022c04e..56f295dff8e43 100644
--- a/src/libcore/tests/cell.rs
+++ b/src/libcore/tests/cell.rs
@@ -109,7 +109,6 @@ fn double_borrow_single_release_no_borrow_mut() {
 
 #[test]
 #[should_panic]
-#[cfg(not(miri))] // Miri does not support panics
 fn discard_doesnt_unborrow() {
     let x = RefCell::new(0);
     let _b = x.borrow();
@@ -350,7 +349,6 @@ fn refcell_ref_coercion() {
 
 #[test]
 #[should_panic]
-#[cfg(not(miri))] // Miri does not support panics
 fn refcell_swap_borrows() {
     let x = RefCell::new(0);
     let _b = x.borrow();
@@ -360,7 +358,6 @@ fn refcell_swap_borrows() {
 
 #[test]
 #[should_panic]
-#[cfg(not(miri))] // Miri does not support panics
 fn refcell_replace_borrows() {
     let x = RefCell::new(0);
     let _b = x.borrow();
diff --git a/src/libcore/tests/iter.rs b/src/libcore/tests/iter.rs
index d880abb181c20..4652fc329dc02 100644
--- a/src/libcore/tests/iter.rs
+++ b/src/libcore/tests/iter.rs
@@ -253,7 +253,6 @@ fn test_iterator_step_by_nth_overflow() {
 
 #[test]
 #[should_panic]
-#[cfg(not(miri))] // Miri does not support panics
 fn test_iterator_step_by_zero() {
     let mut it = (0..).step_by(0);
     it.next();
@@ -1414,7 +1413,6 @@ fn test_rposition() {
 
 #[test]
 #[should_panic]
-#[cfg(not(miri))] // Miri does not support panics
 fn test_rposition_panic() {
     let v: [(Box<_>, Box<_>); 4] =
         [(box 0, box 0), (box 0, box 0),
diff --git a/src/libcore/tests/num/bignum.rs b/src/libcore/tests/num/bignum.rs
index 956c22c998219..b873f1dd0652f 100644
--- a/src/libcore/tests/num/bignum.rs
+++ b/src/libcore/tests/num/bignum.rs
@@ -3,7 +3,6 @@ use core::num::bignum::tests::Big8x3 as Big;
 
 #[test]
 #[should_panic]
-#[cfg(not(miri))] // Miri does not support panics
 fn test_from_u64_overflow() {
     Big::from_u64(0x1000000);
 }
@@ -20,14 +19,12 @@ fn test_add() {
 
 #[test]
 #[should_panic]
-#[cfg(not(miri))] // Miri does not support panics
 fn test_add_overflow_1() {
     Big::from_small(1).add(&Big::from_u64(0xffffff));
 }
 
 #[test]
 #[should_panic]
-#[cfg(not(miri))] // Miri does not support panics
 fn test_add_overflow_2() {
     Big::from_u64(0xffffff).add(&Big::from_small(1));
 }
@@ -45,7 +42,6 @@ fn test_add_small() {
 
 #[test]
 #[should_panic]
-#[cfg(not(miri))] // Miri does not support panics
 fn test_add_small_overflow() {
     Big::from_u64(0xffffff).add_small(1);
 }
@@ -61,14 +57,12 @@ fn test_sub() {
 
 #[test]
 #[should_panic]
-#[cfg(not(miri))] // Miri does not support panics
 fn test_sub_underflow_1() {
     Big::from_u64(0x10665).sub(&Big::from_u64(0x10666));
 }
 
 #[test]
 #[should_panic]
-#[cfg(not(miri))] // Miri does not support panics
 fn test_sub_underflow_2() {
     Big::from_small(0).sub(&Big::from_u64(0x123456));
 }
@@ -82,7 +76,6 @@ fn test_mul_small() {
 
 #[test]
 #[should_panic]
-#[cfg(not(miri))] // Miri does not support panics
 fn test_mul_small_overflow() {
     Big::from_u64(0x800000).mul_small(2);
 }
@@ -101,14 +94,12 @@ fn test_mul_pow2() {
 
 #[test]
 #[should_panic]
-#[cfg(not(miri))] // Miri does not support panics
 fn test_mul_pow2_overflow_1() {
     Big::from_u64(0x1).mul_pow2(24);
 }
 
 #[test]
 #[should_panic]
-#[cfg(not(miri))] // Miri does not support panics
 fn test_mul_pow2_overflow_2() {
     Big::from_u64(0x123).mul_pow2(16);
 }
@@ -127,14 +118,12 @@ fn test_mul_pow5() {
 
 #[test]
 #[should_panic]
-#[cfg(not(miri))] // Miri does not support panics
 fn test_mul_pow5_overflow_1() {
     Big::from_small(1).mul_pow5(12);
 }
 
 #[test]
 #[should_panic]
-#[cfg(not(miri))] // Miri does not support panics
 fn test_mul_pow5_overflow_2() {
     Big::from_small(230).mul_pow5(8);
 }
@@ -152,14 +141,12 @@ fn test_mul_digits() {
 
 #[test]
 #[should_panic]
-#[cfg(not(miri))] // Miri does not support panics
 fn test_mul_digits_overflow_1() {
     Big::from_u64(0x800000).mul_digits(&[2]);
 }
 
 #[test]
 #[should_panic]
-#[cfg(not(miri))] // Miri does not support panics
 fn test_mul_digits_overflow_2() {
     Big::from_u64(0x1000).mul_digits(&[0, 0x10]);
 }
@@ -219,7 +206,6 @@ fn test_get_bit() {
 
 #[test]
 #[should_panic]
-#[cfg(not(miri))] // Miri does not support panics
 fn test_get_bit_out_of_range() {
     Big::from_small(42).get_bit(24);
 }
diff --git a/src/libcore/tests/option.rs b/src/libcore/tests/option.rs
index 87ce2720c5918..b059b134868d9 100644
--- a/src/libcore/tests/option.rs
+++ b/src/libcore/tests/option.rs
@@ -69,7 +69,6 @@ fn test_option_dance() {
 }
 
 #[test] #[should_panic]
-#[cfg(not(miri))] // Miri does not support panics
 fn test_option_too_much_dance() {
     struct A;
     let mut y = Some(A);
@@ -130,7 +129,6 @@ fn test_unwrap() {
 
 #[test]
 #[should_panic]
-#[cfg(not(miri))] // Miri does not support panics
 fn test_unwrap_panic1() {
     let x: Option<isize> = None;
     x.unwrap();
@@ -138,7 +136,6 @@ fn test_unwrap_panic1() {
 
 #[test]
 #[should_panic]
-#[cfg(not(miri))] // Miri does not support panics
 fn test_unwrap_panic2() {
     let x: Option<String> = None;
     x.unwrap();
diff --git a/src/libcore/tests/result.rs b/src/libcore/tests/result.rs
index bbc8568517667..1fab07526a07f 100644
--- a/src/libcore/tests/result.rs
+++ b/src/libcore/tests/result.rs
@@ -117,7 +117,6 @@ fn test_unwrap_or_else() {
 
 #[test]
 #[should_panic]
-#[cfg(not(miri))] // Miri does not support panics
 pub fn test_unwrap_or_else_panic() {
     fn handler(msg: &'static str) -> isize {
         if msg == "I got this." {
@@ -139,7 +138,6 @@ pub fn test_expect_ok() {
 }
 #[test]
 #[should_panic(expected="Got expected error: \"All good\"")]
-#[cfg(not(miri))] // Miri does not support panics
 pub fn test_expect_err() {
     let err: Result<isize, &'static str> = Err("All good");
     err.expect("Got expected error");
@@ -153,7 +151,6 @@ pub fn test_expect_err_err() {
 }
 #[test]
 #[should_panic(expected="Got expected ok: \"All good\"")]
-#[cfg(not(miri))] // Miri does not support panics
 pub fn test_expect_err_ok() {
     let err: Result<&'static str, isize> = Ok("All good");
     err.expect_err("Got expected ok");
diff --git a/src/libcore/tests/slice.rs b/src/libcore/tests/slice.rs
index 31d16e0e32057..ac9c17a0f7c35 100644
--- a/src/libcore/tests/slice.rs
+++ b/src/libcore/tests/slice.rs
@@ -782,7 +782,6 @@ mod slice_index {
     //  to be used in `should_panic`)
     #[test]
     #[should_panic(expected = "out of range")]
-    #[cfg(not(miri))] // Miri does not support panics
     fn assert_range_eq_can_fail_by_panic() {
         assert_range_eq!([0, 1, 2], 0..5, [0, 1, 2]);
     }
@@ -792,7 +791,6 @@ mod slice_index {
     //  to be used in `should_panic`)
     #[test]
     #[should_panic(expected = "==")]
-    #[cfg(not(miri))] // Miri does not support panics
     fn assert_range_eq_can_fail_by_inequality() {
         assert_range_eq!([0, 1, 2], 0..2, [0, 1, 2]);
     }
@@ -842,7 +840,6 @@ mod slice_index {
 
                 #[test]
                 #[should_panic(expected = $expect_msg)]
-                #[cfg(not(miri))] // Miri does not support panics
                 fn index_fail() {
                     let v = $data;
                     let v: &[_] = &v;
@@ -851,7 +848,6 @@ mod slice_index {
 
                 #[test]
                 #[should_panic(expected = $expect_msg)]
-                #[cfg(not(miri))] // Miri does not support panics
                 fn index_mut_fail() {
                     let mut v = $data;
                     let v: &mut [_] = &mut v;
@@ -1304,7 +1300,6 @@ fn test_copy_within() {
 
 #[test]
 #[should_panic(expected = "src is out of bounds")]
-#[cfg(not(miri))] // Miri does not support panics
 fn test_copy_within_panics_src_too_long() {
     let mut bytes = *b"Hello, World!";
     // The length is only 13, so 14 is out of bounds.
@@ -1313,7 +1308,6 @@ fn test_copy_within_panics_src_too_long() {
 
 #[test]
 #[should_panic(expected = "dest is out of bounds")]
-#[cfg(not(miri))] // Miri does not support panics
 fn test_copy_within_panics_dest_too_long() {
     let mut bytes = *b"Hello, World!";
     // The length is only 13, so a slice of length 4 starting at index 10 is out of bounds.
@@ -1321,7 +1315,6 @@ fn test_copy_within_panics_dest_too_long() {
 }
 #[test]
 #[should_panic(expected = "src end is before src start")]
-#[cfg(not(miri))] // Miri does not support panics
 fn test_copy_within_panics_src_inverted() {
     let mut bytes = *b"Hello, World!";
     // 2 is greater than 1, so this range is invalid.
diff --git a/src/libcore/tests/time.rs b/src/libcore/tests/time.rs
index 09aae4583482f..6efd22572dc18 100644
--- a/src/libcore/tests/time.rs
+++ b/src/libcore/tests/time.rs
@@ -107,14 +107,12 @@ fn checked_sub() {
 
 #[test]
 #[should_panic]
-#[cfg(not(miri))] // Miri does not support panics
 fn sub_bad1() {
     let _ = Duration::new(0, 0) - Duration::new(0, 1);
 }
 
 #[test]
 #[should_panic]
-#[cfg(not(miri))] // Miri does not support panics
 fn sub_bad2() {
     let _ = Duration::new(0, 0) - Duration::new(1, 0);
 }

From 52d9fa827d3cf5ef5fc0e2042ca1fc7f6dc391ed Mon Sep 17 00:00:00 2001
From: Ralf Jung <post@ralfj.de>
Date: Sun, 10 Mar 2019 17:52:45 +0100
Subject: [PATCH 21/22] enabled too many tests

---
 src/liballoc/tests/binary_heap.rs | 2 +-
 src/liballoc/tests/slice.rs       | 2 ++
 2 files changed, 3 insertions(+), 1 deletion(-)

diff --git a/src/liballoc/tests/binary_heap.rs b/src/liballoc/tests/binary_heap.rs
index a97a790f5a2d8..0930f8dacd494 100644
--- a/src/liballoc/tests/binary_heap.rs
+++ b/src/liballoc/tests/binary_heap.rs
@@ -282,7 +282,7 @@ fn assert_covariance() {
 //
 // Destructors must be called exactly once per element.
 #[test]
-#[cfg(not(miri))] // Miri does not support entropy
+#[cfg(not(miri))] // Miri does not support panics nor entropy
 fn panic_safe() {
     static DROP_COUNTER: AtomicUsize = AtomicUsize::new(0);
 
diff --git a/src/liballoc/tests/slice.rs b/src/liballoc/tests/slice.rs
index fb99c95fc6842..b54c128a0249a 100644
--- a/src/liballoc/tests/slice.rs
+++ b/src/liballoc/tests/slice.rs
@@ -1397,6 +1397,7 @@ fn test_box_slice_clone() {
 #[test]
 #[allow(unused_must_use)] // here, we care about the side effects of `.clone()`
 #[cfg_attr(target_os = "emscripten", ignore)]
+#[cfg(not(miri))] // Miri does not support threads nor entropy
 fn test_box_slice_clone_panics() {
     use std::sync::Arc;
     use std::sync::atomic::{AtomicUsize, Ordering};
@@ -1588,6 +1589,7 @@ thread_local!(static SILENCE_PANIC: Cell<bool> = Cell::new(false));
 
 #[test]
 #[cfg_attr(target_os = "emscripten", ignore)] // no threads
+#[cfg(not(miri))] // Miri does not support threads nor entropy
 fn panic_safe() {
     let prev = panic::take_hook();
     panic::set_hook(Box::new(move |info| {

From 7285b5630b36b3e6aba135f91ded546e82775288 Mon Sep 17 00:00:00 2001
From: Matthew Jasper <mjjasper1@gmail.com>
Date: Wed, 27 Feb 2019 21:01:42 +0000
Subject: [PATCH 22/22] Make migrate mode work at item level granularity

---
 src/librustc/middle/expr_use_visitor.rs       |  8 +++--
 .../borrowck/gather_loans/mod.rs              | 18 +++++++++++
 src/librustc_mir/borrow_check/mod.rs          | 28 +++-------------
 ...e-58776-borrowck-scans-children.ast.stderr | 15 +++++++++
 ...776-borrowck-scans-children.migrate.stderr | 32 +++++++++++++++++++
 ...e-58776-borrowck-scans-children.nll.stderr | 32 +++++++++++++++++++
 .../issue-58776-borrowck-scans-children.rs    | 21 ++++++++++++
 7 files changed, 129 insertions(+), 25 deletions(-)
 create mode 100644 src/test/ui/borrowck/issue-58776-borrowck-scans-children.ast.stderr
 create mode 100644 src/test/ui/borrowck/issue-58776-borrowck-scans-children.migrate.stderr
 create mode 100644 src/test/ui/borrowck/issue-58776-borrowck-scans-children.nll.stderr
 create mode 100644 src/test/ui/borrowck/issue-58776-borrowck-scans-children.rs

diff --git a/src/librustc/middle/expr_use_visitor.rs b/src/librustc/middle/expr_use_visitor.rs
index 78a9e406c95e9..8ada67efaafdd 100644
--- a/src/librustc/middle/expr_use_visitor.rs
+++ b/src/librustc/middle/expr_use_visitor.rs
@@ -82,6 +82,9 @@ pub trait Delegate<'tcx> {
               assignment_span: Span,
               assignee_cmt: &mc::cmt_<'tcx>,
               mode: MutateMode);
+
+    // A nested closure or generator - only one layer deep.
+    fn nested_body(&mut self, _body_id: hir::BodyId) {}
 }
 
 #[derive(Copy, Clone, PartialEq, Debug)]
@@ -531,8 +534,9 @@ impl<'a, 'gcx, 'tcx> ExprUseVisitor<'a, 'gcx, 'tcx> {
                 self.consume_expr(&base);
             }
 
-            hir::ExprKind::Closure(.., fn_decl_span, _) => {
-                self.walk_captures(expr, fn_decl_span)
+            hir::ExprKind::Closure(_, _, body_id, fn_decl_span, _) => {
+                self.delegate.nested_body(body_id);
+                self.walk_captures(expr, fn_decl_span);
             }
 
             hir::ExprKind::Box(ref base) => {
diff --git a/src/librustc_borrowck/borrowck/gather_loans/mod.rs b/src/librustc_borrowck/borrowck/gather_loans/mod.rs
index bf730ba41f428..1e3364ecb9a34 100644
--- a/src/librustc_borrowck/borrowck/gather_loans/mod.rs
+++ b/src/librustc_borrowck/borrowck/gather_loans/mod.rs
@@ -153,6 +153,24 @@ impl<'a, 'tcx> euv::Delegate<'tcx> for GatherLoanCtxt<'a, 'tcx> {
                      .node_type(id);
         gather_moves::gather_decl(self.bccx, &self.move_data, id, ty);
     }
+
+    fn nested_body(&mut self, body_id: hir::BodyId) {
+        debug!("nested_body(body_id={:?})", body_id);
+        // rust-lang/rust#58776: MIR and AST borrow check disagree on where
+        // certain closure errors are reported. As such migrate borrowck has to
+        // operate at the level of items, rather than bodies. Check if the
+        // contained closure had any errors and set `signalled_any_error` if it
+        // has.
+        let bccx = self.bccx;
+        if bccx.tcx.migrate_borrowck() {
+            if let SignalledError::NoErrorsSeen = bccx.signalled_any_error.get() {
+                let closure_def_id = bccx.tcx.hir().body_owner_def_id(body_id);
+                debug!("checking closure: {:?}", closure_def_id);
+
+                bccx.signalled_any_error.set(bccx.tcx.borrowck(closure_def_id).signalled_any_error);
+            }
+        }
+    }
 }
 
 /// Implements the A-* rules in README.md.
diff --git a/src/librustc_mir/borrow_check/mod.rs b/src/librustc_mir/borrow_check/mod.rs
index d5dfdf0add528..0bdf44c2ae049 100644
--- a/src/librustc_mir/borrow_check/mod.rs
+++ b/src/librustc_mir/borrow_check/mod.rs
@@ -329,30 +329,12 @@ fn do_mir_borrowck<'a, 'gcx, 'tcx>(
             // When borrowck=migrate, check if AST-borrowck would
             // error on the given code.
 
-            // rust-lang/rust#55492: loop over parents to ensure that
-            // errors that AST-borrowck only detects in some parent of
-            // a closure still allows NLL to signal an error.
-            let mut curr_def_id = def_id;
-            let signalled_any_error = loop {
-                match tcx.borrowck(curr_def_id).signalled_any_error {
-                    SignalledError::NoErrorsSeen => {
-                        // keep traversing (and borrow-checking) parents
-                    }
-                    SignalledError::SawSomeError => {
-                        // stop search here
-                        break SignalledError::SawSomeError;
-                    }
-                }
-
-                if tcx.is_closure(curr_def_id) {
-                    curr_def_id = tcx.parent_def_id(curr_def_id)
-                        .expect("a closure must have a parent_def_id");
-                } else {
-                    break SignalledError::NoErrorsSeen;
-                }
-            };
+            // rust-lang/rust#55492, rust-lang/rust#58776 check the base def id
+            // for errors. AST borrowck is responsible for aggregating
+            // `signalled_any_error` from all of the nested closures here.
+            let base_def_id = tcx.closure_base_def_id(def_id);
 
-            match signalled_any_error {
+            match tcx.borrowck(base_def_id).signalled_any_error {
                 SignalledError::NoErrorsSeen => {
                     // if AST-borrowck signalled no errors, then
                     // downgrade all the buffered MIR-borrowck errors
diff --git a/src/test/ui/borrowck/issue-58776-borrowck-scans-children.ast.stderr b/src/test/ui/borrowck/issue-58776-borrowck-scans-children.ast.stderr
new file mode 100644
index 0000000000000..9e0b0aac1e3c6
--- /dev/null
+++ b/src/test/ui/borrowck/issue-58776-borrowck-scans-children.ast.stderr
@@ -0,0 +1,15 @@
+error[E0597]: `**greeting` does not live long enough
+  --> $DIR/issue-58776-borrowck-scans-children.rs:10:24
+   |
+LL |     let res = (|| (|| &greeting)())();
+   |                    --  ^^^^^^^^     - borrowed value only lives until here
+   |                    |   |
+   |                    |   borrowed value does not live long enough
+   |                    capture occurs here
+...
+LL | }
+   | - borrowed value needs to live until here
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0597`.
diff --git a/src/test/ui/borrowck/issue-58776-borrowck-scans-children.migrate.stderr b/src/test/ui/borrowck/issue-58776-borrowck-scans-children.migrate.stderr
new file mode 100644
index 0000000000000..bd8f2286f170c
--- /dev/null
+++ b/src/test/ui/borrowck/issue-58776-borrowck-scans-children.migrate.stderr
@@ -0,0 +1,32 @@
+error[E0506]: cannot assign to `greeting` because it is borrowed
+  --> $DIR/issue-58776-borrowck-scans-children.rs:13:5
+   |
+LL |     let res = (|| (|| &greeting)())();
+   |                --      -------- borrow occurs due to use in closure
+   |                |
+   |                borrow of `greeting` occurs here
+...
+LL |     greeting = "DEALLOCATED".to_string();
+   |     ^^^^^^^^ assignment to borrowed `greeting` occurs here
+...
+LL |     println!("thread result: {:?}", res);
+   |                                     --- borrow later used here
+
+error[E0505]: cannot move out of `greeting` because it is borrowed
+  --> $DIR/issue-58776-borrowck-scans-children.rs:16:10
+   |
+LL |     let res = (|| (|| &greeting)())();
+   |                --      -------- borrow occurs due to use in closure
+   |                |
+   |                borrow of `greeting` occurs here
+...
+LL |     drop(greeting);
+   |          ^^^^^^^^ move out of `greeting` occurs here
+...
+LL |     println!("thread result: {:?}", res);
+   |                                     --- borrow later used here
+
+error: aborting due to 2 previous errors
+
+Some errors occurred: E0505, E0506.
+For more information about an error, try `rustc --explain E0505`.
diff --git a/src/test/ui/borrowck/issue-58776-borrowck-scans-children.nll.stderr b/src/test/ui/borrowck/issue-58776-borrowck-scans-children.nll.stderr
new file mode 100644
index 0000000000000..bd8f2286f170c
--- /dev/null
+++ b/src/test/ui/borrowck/issue-58776-borrowck-scans-children.nll.stderr
@@ -0,0 +1,32 @@
+error[E0506]: cannot assign to `greeting` because it is borrowed
+  --> $DIR/issue-58776-borrowck-scans-children.rs:13:5
+   |
+LL |     let res = (|| (|| &greeting)())();
+   |                --      -------- borrow occurs due to use in closure
+   |                |
+   |                borrow of `greeting` occurs here
+...
+LL |     greeting = "DEALLOCATED".to_string();
+   |     ^^^^^^^^ assignment to borrowed `greeting` occurs here
+...
+LL |     println!("thread result: {:?}", res);
+   |                                     --- borrow later used here
+
+error[E0505]: cannot move out of `greeting` because it is borrowed
+  --> $DIR/issue-58776-borrowck-scans-children.rs:16:10
+   |
+LL |     let res = (|| (|| &greeting)())();
+   |                --      -------- borrow occurs due to use in closure
+   |                |
+   |                borrow of `greeting` occurs here
+...
+LL |     drop(greeting);
+   |          ^^^^^^^^ move out of `greeting` occurs here
+...
+LL |     println!("thread result: {:?}", res);
+   |                                     --- borrow later used here
+
+error: aborting due to 2 previous errors
+
+Some errors occurred: E0505, E0506.
+For more information about an error, try `rustc --explain E0505`.
diff --git a/src/test/ui/borrowck/issue-58776-borrowck-scans-children.rs b/src/test/ui/borrowck/issue-58776-borrowck-scans-children.rs
new file mode 100644
index 0000000000000..378969f9a1867
--- /dev/null
+++ b/src/test/ui/borrowck/issue-58776-borrowck-scans-children.rs
@@ -0,0 +1,21 @@
+// ignore-compare-mode-nll
+
+// revisions: ast migrate nll
+
+//[migrate]compile-flags: -Z borrowck=migrate
+#![cfg_attr(nll, feature(nll))]
+
+fn main() {
+    let mut greeting = "Hello world!".to_string();
+    let res = (|| (|| &greeting)())();
+    //[ast]~^ ERROR does not live long enough
+
+    greeting = "DEALLOCATED".to_string();
+    //[migrate]~^ ERROR cannot assign
+    //[nll]~^^ ERROR cannot assign
+    drop(greeting);
+    //[migrate]~^ ERROR cannot move
+    //[nll]~^^ ERROR cannot move
+
+    println!("thread result: {:?}", res);
+}