no-panic v0.1.14 am: 424ae2f8d0 am: db13a92ef6

Original change: https://android-review.googlesource.com/c/platform/external/rust/crates/no-panic/+/1523840

MUST ONLY BE SUBMITTED BY AUTOMERGER

Change-Id: Iae1e7202678e040b10e16d0c2158b1b780023971

16 files changed, 936 insertions, 0 deletions

diff --git a/.cargo_vcs_info.json b/.cargo_vcs_info.json
new file mode 100644
index 0000000..02fa1cf
--- /dev/null
+++ b/.cargo_vcs_info.json
@@ -0,0 +1,5 @@
+{
+  "git": {
+    "sha1": "c9b18d4a8af4393dc9d9e5efb4d3cc7a56c41d92"
+  }
+}
diff --git a/.github/FUNDING.yml b/.github/FUNDING.yml
new file mode 100644
index 0000000..7507077
--- /dev/null
+++ b/.github/FUNDING.yml
@@ -0,0 +1 @@
+github: dtolnay
diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
new file mode 100644
index 0000000..921c271
--- /dev/null
+++ b/.github/workflows/ci.yml
@@ -0,0 +1,29 @@
+name: CI
+
+on:
+  push:
+  pull_request:
+  schedule: [cron: "40 1 * * *"]
+
+jobs:
+  test:
+    name: Rust ${{matrix.rust}}
+    runs-on: ubuntu-latest
+    strategy:
+      fail-fast: false
+      matrix:
+        rust: [nightly, beta, stable, 1.32.0]
+    steps:
+      - uses: actions/checkout@v2
+      - uses: dtolnay/rust-toolchain@master
+        with:
+          toolchain: ${{matrix.rust}}
+      - run: cargo test
+
+  msrv:
+    name: Rust 1.31.0
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+      - uses: dtolnay/rust-toolchain@1.31.0
+      - run: cargo build
diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..6936990
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,3 @@
+/target
+**/*.rs.bk
+Cargo.lock
diff --git a/Cargo.toml b/Cargo.toml
new file mode 100644
index 0000000..c854821
--- /dev/null
+++ b/Cargo.toml
@@ -0,0 +1,38 @@
+# THIS FILE IS AUTOMATICALLY GENERATED BY CARGO
+#
+# When uploading crates to the registry Cargo will automatically
+# "normalize" Cargo.toml files for maximal compatibility
+# with all versions of Cargo and also rewrite `path` dependencies
+# to registry (e.g., crates.io) dependencies
+#
+# If you believe there's an error in this file please file an
+# issue against the rust-lang/cargo repository. If you're
+# editing this file be aware that the upstream Cargo.toml
+# will likely look very different (and much more reasonable)
+
+[package]
+edition = "2018"
+name = "no-panic"
+version = "0.1.14"
+authors = ["David Tolnay <dtolnay@gmail.com>"]
+description = "Attribute macro to require that the compiler prove a function can't ever panic."
+documentation = "https://github.com/dtolnay/no-panic"
+readme = "README.md"
+license = "MIT OR Apache-2.0"
+repository = "https://github.com/dtolnay/no-panic"
+[package.metadata.docs.rs]
+targets = ["x86_64-unknown-linux-gnu"]
+
+[lib]
+proc-macro = true
+[dependencies.proc-macro2]
+version = "1.0"
+
+[dependencies.quote]
+version = "1.0"
+
+[dependencies.syn]
+version = "1.0"
+features = ["full"]
+[dev-dependencies.tempfile]
+version = "3.0"
diff --git a/Cargo.toml.orig b/Cargo.toml.orig
new file mode 100644
index 0000000..9be6d3f
--- /dev/null
+++ b/Cargo.toml.orig
@@ -0,0 +1,24 @@
+[package]
+name = "no-panic"
+version = "0.1.14"
+authors = ["David Tolnay <dtolnay@gmail.com>"]
+edition = "2018"
+license = "MIT OR Apache-2.0"
+description = "Attribute macro to require that the compiler prove a function can't ever panic."
+repository = "https://github.com/dtolnay/no-panic"
+documentation = "https://github.com/dtolnay/no-panic"
+readme = "README.md"
+
+[lib]
+proc-macro = true
+
+[dependencies]
+proc-macro2 = "1.0"
+quote = "1.0"
+syn = { version = "1.0", features = ["full"] }
+
+[dev-dependencies]
+tempfile = "3.0"
+
+[package.metadata.docs.rs]
+targets = ["x86_64-unknown-linux-gnu"]
diff --git a/LICENSE b/LICENSE
new file mode 120000
index 0000000..6b579aa
--- /dev/null
+++ b/LICENSE
@@ -0,0 +1 @@
+LICENSE-APACHE
\ No newline at end of file
diff --git a/LICENSE-APACHE b/LICENSE-APACHE
new file mode 100644
index 0000000..16fe87b
--- /dev/null
+++ b/LICENSE-APACHE
@@ -0,0 +1,201 @@
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diff --git a/LICENSE-MIT b/LICENSE-MIT
new file mode 100644
index 0000000..31aa793
--- /dev/null
+++ b/LICENSE-MIT
@@ -0,0 +1,23 @@
+Permission is hereby granted, free of charge, to any
+person obtaining a copy of this software and associated
+documentation files (the "Software"), to deal in the
+Software without restriction, including without
+limitation the rights to use, copy, modify, merge,
+publish, distribute, sublicense, and/or sell copies of
+the Software, and to permit persons to whom the Software
+is furnished to do so, subject to the following
+conditions:
+
+The above copyright notice and this permission notice
+shall be included in all copies or substantial portions
+of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF
+ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED
+TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
+PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT
+SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
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diff --git a/METADATA b/METADATA
new file mode 100644
index 0000000..b49a5e0
--- /dev/null
+++ b/METADATA
@@ -0,0 +1,19 @@
+name: "no-panic"
+description: "Attribute macro to require that the compiler prove a function can\'t ever panic."
+third_party {
+  url {
+    type: HOMEPAGE
+    value: "https://crates.io/crates/no-panic"
+  }
+  url {
+    type: ARCHIVE
+    value: "https://static.crates.io/crates/no-panic/no-panic-0.1.14.crate"
+  }
+  version: "0.1.14"
+  license_type: NOTICE
+  last_upgrade_date {
+    year: 2020
+    month: 12
+    day: 9
+  }
+}
diff --git a/MODULE_LICENSE_APACHE2 b/MODULE_LICENSE_APACHE2
new file mode 100644
index 0000000..e69de29
--- /dev/null
+++ b/MODULE_LICENSE_APACHE2
diff --git a/OWNERS b/OWNERS
new file mode 100644
index 0000000..46fc303
--- /dev/null
+++ b/OWNERS
@@ -0,0 +1 @@
+include platform/prebuilts/rust:/OWNERS
diff --git a/README.md b/README.md
new file mode 100644
index 0000000..a1c09fb
--- /dev/null
+++ b/README.md
@@ -0,0 +1,127 @@
+\#\[no\_panic\]
+===============
+
+[<img alt="github" src="https://img.shields.io/badge/github-dtolnay/no--panic-8da0cb?style=for-the-badge&labelColor=555555&logo=github" height="20">](https://github.com/dtolnay/no-panic)
+[<img alt="crates.io" src="https://img.shields.io/crates/v/no-panic.svg?style=for-the-badge&color=fc8d62&logo=rust" height="20">](https://crates.io/crates/no-panic)
+[<img alt="docs.rs" src="https://img.shields.io/badge/docs.rs-no--panic-66c2a5?style=for-the-badge&labelColor=555555&logoColor=white&logo=data:image/svg+xml;base64,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" height="20">](https://docs.rs/no-panic)
+[<img alt="build status" src="https://img.shields.io/github/workflow/status/dtolnay/no-panic/CI/master?style=for-the-badge" height="20">](https://github.com/dtolnay/no-panic/actions?query=branch%3Amaster)
+
+A Rust attribute macro to require that the compiler prove a function can't ever
+panic.
+
+```toml
+[dependencies]
+no-panic = "0.1"
+```
+
+```rust
+use no_panic::no_panic;
+
+#[no_panic]
+fn demo(s: &str) -> &str {
+    &s[1..]
+}
+
+fn main() {
+    println!("{}", demo("input string"));
+}
+```
+
+If the function does panic (or the compiler fails to prove that the function
+cannot panic), the program fails to compile with a linker error that identifies
+the function name. Let's trigger that by passing a string that cannot be sliced
+at the first byte:
+
+```rust
+fn main() {
+    println!("{}", demo("\u{1f980}input string"));
+}
+```
+
+```console
+   Compiling no-panic-demo v0.0.1
+error: linking with `cc` failed: exit code: 1
+  |
+  = note: /no-panic-demo/target/release/deps/no_panic_demo-7170785b672ae322.no_p
+anic_demo1-cba7f4b666ccdbcbbf02b7348e5df1b2.rs.rcgu.o: In function `_$LT$no_pani
+c_demo..demo..__NoPanic$u20$as$u20$core..ops..drop..Drop$GT$::drop::h72f8f423002
+b8d9f':
+          no_panic_demo1-cba7f4b666ccdbcbbf02b7348e5df1b2.rs:(.text._ZN72_$LT$no
+_panic_demo..demo..__NoPanic$u20$as$u20$core..ops..drop..Drop$GT$4drop17h72f8f42
+3002b8d9fE+0x2): undefined reference to `
+
+          ERROR[no-panic]: detected panic in function `demo`
+          '
+          collect2: error: ld returned 1 exit status
+```
+
+The error is not stellar but notice the ERROR\[no-panic\] part at the end that
+provides the name of the offending function.
+
+*Compiler support: requires rustc 1.31+*
+
+<br>
+
+### Caveats
+
+- Functions that require some amount of optimization to prove that they do not
+  panic may no longer compile in debug mode after being marked `#[no_panic]`.
+
+- Panic detection happens at link time across the entire dependency graph, so
+  any Cargo commands that do not invoke a linker will not trigger panic
+  detection. This includes `cargo build` of library crates and `cargo check` of
+  binary and library crates.
+
+- The attribute is useless in code built with `panic = "abort"`.
+
+If you find that code requires optimization to pass `#[no_panic]`, either make
+no-panic an optional dependency that you only enable in release builds, or add a
+section like the following to Cargo.toml to enable very basic optimization in
+debug builds.
+
+```toml
+[profile.dev]
+opt-level = 1
+```
+
+If the code that you need to prove isn't panicking makes function calls to
+non-generic non-inline functions from a different crate, you may need thin LTO
+enabled for the linker to deduce those do not panic.
+
+```toml
+[profile.release]
+lto = "thin"
+```
+
+If you want no\_panic to just assume that some function you call doesn't panic,
+and get Undefined Behavior if it does at runtime, see [dtolnay/no-panic#16]; try
+wrapping that call in an `unsafe extern "C"` wrapper.
+
+[dtolnay/no-panic#16]: https://github.com/dtolnay/no-panic/issues/16
+
+<br>
+
+### Acknowledgments
+
+The linker error technique is based on [Kixunil]'s crate [`dont_panic`]. Check
+out that crate for other convenient ways to require absence of panics.
+
+[Kixunil]: https://github.com/Kixunil
+[`dont_panic`]: https://github.com/Kixunil/dont_panic
+
+<br>
+
+#### License
+
+<sup>
+Licensed under either of <a href="LICENSE-APACHE">Apache License, Version
+2.0</a> or <a href="LICENSE-MIT">MIT license</a> at your option.
+</sup>
+
+<br>
+
+<sub>
+Unless you explicitly state otherwise, any contribution intentionally submitted
+for inclusion in this crate by you, as defined in the Apache-2.0 license, shall
+be dual licensed as above, without any additional terms or conditions.
+</sub>
diff --git a/src/lib.rs b/src/lib.rs
new file mode 100644
index 0000000..2c9bd77
--- /dev/null
+++ b/src/lib.rs
@@ -0,0 +1,204 @@
+//! [![github]](https://github.com/dtolnay/no-panic)&ensp;[![crates-io]](https://crates.io/crates/no-panic)&ensp;[![docs-rs]](https://docs.rs/no-panic)
+//!
+//! [github]: https://img.shields.io/badge/github-8da0cb?style=for-the-badge&labelColor=555555&logo=github
+//! [crates-io]: https://img.shields.io/badge/crates.io-fc8d62?style=for-the-badge&labelColor=555555&logo=rust
+//! [docs-rs]: https://img.shields.io/badge/docs.rs-66c2a5?style=for-the-badge&labelColor=555555&logoColor=white&logo=data:image/svg+xml;base64,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
+//!
+//! <br>
+//!
+//! A Rust attribute macro to require that the compiler prove a function can't
+//! ever panic.
+//!
+//! ```toml
+//! [dependencies]
+//! no-panic = "0.1"
+//! ```
+//!
+//! ```
+//! use no_panic::no_panic;
+//!
+//! #[no_panic]
+//! fn demo(s: &str) -> &str {
+//!     &s[1..]
+//! }
+//!
+//! fn main() {
+//!     # fn demo(s: &str) -> &str {
+//!     #     &s[1..]
+//!     # }
+//!     #
+//!     println!("{}", demo("input string"));
+//! }
+//! ```
+//!
+//! If the function does panic (or the compiler fails to prove that the function
+//! cannot panic), the program fails to compile with a linker error that
+//! identifies the function name. Let's trigger that by passing a string that
+//! cannot be sliced at the first byte:
+//!
+//! ```should_panic
+//! # fn demo(s: &str) -> &str {
+//! #     &s[1..]
+//! # }
+//! #
+//! fn main() {
+//!     println!("{}", demo("\u{1f980}input string"));
+//! }
+//! ```
+//!
+//! ```console
+//!    Compiling no-panic-demo v0.0.1
+//! error: linking with `cc` failed: exit code: 1
+//!   |
+//!   = note: /no-panic-demo/target/release/deps/no_panic_demo-7170785b672ae322.no_p
+//! anic_demo1-cba7f4b666ccdbcbbf02b7348e5df1b2.rs.rcgu.o: In function `_$LT$no_pani
+//! c_demo..demo..__NoPanic$u20$as$u20$core..ops..drop..Drop$GT$::drop::h72f8f423002
+//! b8d9f':
+//!           no_panic_demo1-cba7f4b666ccdbcbbf02b7348e5df1b2.rs:(.text._ZN72_$LT$no
+//! _panic_demo..demo..__NoPanic$u20$as$u20$core..ops..drop..Drop$GT$4drop17h72f8f42
+//! 3002b8d9fE+0x2): undefined reference to `
+//!
+//!           ERROR[no-panic]: detected panic in function `demo`
+//!           '
+//!           collect2: error: ld returned 1 exit status
+//! ```
+//!
+//! The error is not stellar but notice the ERROR\[no-panic\] part at the end
+//! that provides the name of the offending function.
+//!
+//! *Compiler support: requires rustc 1.31+*
+//!
+//! <br>
+//!
+//! ## Caveats
+//!
+//! - Functions that require some amount of optimization to prove that they do
+//!   not panic may no longer compile in debug mode after being marked
+//!   `#[no_panic]`.
+//!
+//! - Panic detection happens at link time across the entire dependency graph,
+//!   so any Cargo commands that do not invoke a linker will not trigger panic
+//!   detection. This includes `cargo build` of library crates and `cargo check`
+//!   of binary and library crates.
+//!
+//! - The attribute is useless in code built with `panic = "abort"`.
+//!
+//! If you find that code requires optimization to pass `#[no_panic]`, either
+//! make no-panic an optional dependency that you only enable in release builds,
+//! or add a section like the following to Cargo.toml to enable very basic
+//! optimization in debug builds.
+//!
+//! ```toml
+//! [profile.dev]
+//! opt-level = 1
+//! ```
+//!
+//! If the code that you need to prove isn't panicking makes function calls to
+//! non-generic non-inline functions from a different crate, you may need thin
+//! LTO enabled for the linker to deduce those do not panic.
+//!
+//! ```toml
+//! [profile.release]
+//! lto = "thin"
+//! ```
+//!
+//! If you want no_panic to just assume that some function you call doesn't
+//! panic, and get Undefined Behavior if it does at runtime, see
+//! [dtolnay/no-panic#16]; try wrapping that call in an `unsafe extern "C"`
+//! wrapper.
+//!
+//! [dtolnay/no-panic#16]: https://github.com/dtolnay/no-panic/issues/16
+//!
+//! <br>
+//!
+//! ## Acknowledgments
+//!
+//! The linker error technique is based on [Kixunil]'s crate [`dont_panic`].
+//! Check out that crate for other convenient ways to require absence of panics.
+//!
+//! [Kixunil]: https://github.com/Kixunil
+//! [`dont_panic`]: https://github.com/Kixunil/dont_panic
+
+extern crate proc_macro;
+
+use proc_macro::TokenStream;
+use proc_macro2::Span;
+use quote::quote;
+use syn::{parse_macro_input, parse_quote, Attribute, FnArg, Ident, ItemFn, PatType, ReturnType};
+
+#[proc_macro_attribute]
+pub fn no_panic(args: TokenStream, function: TokenStream) -> TokenStream {
+    assert!(args.is_empty());
+
+    let mut function = parse_macro_input!(function as ItemFn);
+
+    let mut move_self = None;
+    let mut arg_pat = Vec::new();
+    let mut arg_val = Vec::new();
+    for (i, input) in function.sig.inputs.iter_mut().enumerate() {
+        let numbered = Ident::new(&format!("__arg{}", i), Span::call_site());
+        match input {
+            FnArg::Typed(PatType { pat, .. }) => {
+                arg_pat.push(quote!(#pat));
+                arg_val.push(quote!(#numbered));
+                *pat = parse_quote!(mut #numbered);
+            }
+            FnArg::Receiver(_) => {
+                move_self = Some(quote! {
+                    if false {
+                        loop {}
+                        #[allow(unreachable_code)]
+                        {
+                            let __self = self;
+                        }
+                    }
+                });
+            }
+        }
+    }
+
+    let has_inline = function
+        .attrs
+        .iter()
+        .flat_map(Attribute::parse_meta)
+        .any(|meta| meta.path().is_ident("inline"));
+    if !has_inline {
+        function.attrs.push(parse_quote!(#[inline]));
+    }
+
+    let ret = match &function.sig.output {
+        ReturnType::Default => quote!(-> ()),
+        output @ ReturnType::Type(..) => quote!(#output),
+    };
+    let stmts = function.block.stmts;
+    let message = format!(
+        "\n\nERROR[no-panic]: detected panic in function `{}`\n",
+        function.sig.ident,
+    );
+    function.block = Box::new(parse_quote!({
+        struct __NoPanic;
+        extern "C" {
+            #[link_name = #message]
+            fn trigger() -> !;
+        }
+        impl core::ops::Drop for __NoPanic {
+            fn drop(&mut self) {
+                unsafe {
+                    trigger();
+                }
+            }
+        }
+        let __guard = __NoPanic;
+        let __result = (move || #ret {
+            #move_self
+            #(
+                let #arg_pat = #arg_val;
+            )*
+            #(#stmts)*
+        })();
+        core::mem::forget(__guard);
+        __result
+    }));
+
+    TokenStream::from(quote!(#function))
+}
diff --git a/tests/compiletest/mod.rs b/tests/compiletest/mod.rs
new file mode 100644
index 0000000..f4e26c1
--- /dev/null
+++ b/tests/compiletest/mod.rs
@@ -0,0 +1,79 @@
+use std::fs;
+use std::process::Command;
+use std::sync::Once;
+
+pub fn setup() {
+    static BUILD: Once = Once::new();
+    BUILD.call_once(|| {
+        let status = Command::new("cargo")
+            .arg("build")
+            .status()
+            .expect("failed to build");
+        assert!(status.success());
+    });
+}
+
+pub fn contains_panic(name: &str, code: &str) -> bool {
+    let tempdir = tempfile::tempdir().unwrap();
+
+    let prelude = stringify! {
+        use no_panic::no_panic;
+    };
+
+    let rs = tempdir.path().join(format!("{}.rs", name));
+    fs::write(&rs, format!("{}{}", prelude, code)).unwrap();
+
+    let status = Command::new("rustc")
+        .arg("--crate-name")
+        .arg(name)
+        .arg(rs)
+        .arg("--edition=2018")
+        .arg("-C")
+        .arg("opt-level=3")
+        .arg("--emit=asm")
+        .arg("--out-dir")
+        .arg(tempdir.path())
+        .arg("--extern")
+        .arg("no_panic=target/debug/libno_panic.so")
+        .status()
+        .expect("failed to execute rustc");
+    assert!(status.success());
+
+    let asm = tempdir.path().join(format!("{}.s", name));
+    let asm = fs::read_to_string(asm).unwrap();
+    asm.contains("detected panic in function")
+}
+
+macro_rules! assert_no_panic {
+    ($(mod $name:ident { $($content:tt)* })*) => {
+        mod no_panic {
+            use crate::compiletest;
+            $(
+                #[test]
+                fn $name() {
+                    compiletest::setup();
+                    let name = stringify!($name);
+                    let content = stringify!($($content)*);
+                    assert!(!compiletest::contains_panic(name, content));
+                }
+            )*
+        }
+    };
+}
+
+macro_rules! assert_link_error {
+    ($(mod $name:ident { $($content:tt)* })*) => {
+        mod link_error {
+            use crate::compiletest;
+            $(
+                #[test]
+                fn $name() {
+                    compiletest::setup();
+                    let name = stringify!($name);
+                    let content = stringify!($($content)*);
+                    assert!(compiletest::contains_panic(name, content));
+                }
+            )*
+        }
+    };
+}
diff --git a/tests/test.rs b/tests/test.rs
new file mode 100644
index 0000000..a7da4d4
--- /dev/null
+++ b/tests/test.rs
@@ -0,0 +1,181 @@
+#[macro_use]
+mod compiletest;
+
+assert_no_panic! {
+    mod test_readme {
+        #[no_panic]
+        fn demo(s: &str) -> &str {
+            &s[1..]
+        }
+
+        fn main() {
+            println!("{}", demo("input string"));
+        }
+    }
+
+    mod test_method_in_impl {
+        struct S;
+
+        impl S {
+            #[no_panic]
+            fn demo(self) -> &'static str {
+                "test"
+            }
+        }
+
+        fn main() {
+            println!("{}", S.demo());
+        }
+    }
+
+    mod test_lifetime_elision {
+        struct Buffer {
+            bytes: [u8; 24],
+        }
+
+        #[no_panic]
+        fn demo(buffer: &mut Buffer) -> &[u8] {
+            &buffer.bytes[..]
+        }
+
+        fn main() {
+            let mut buffer = Buffer {
+                bytes: [0u8; 24],
+            };
+            println!("{:?}", demo(&mut buffer));
+        }
+    }
+
+    mod test_receiver_lifetime_elision {
+        struct Buffer {
+            bytes: [u8; 24],
+        }
+
+        impl Buffer {
+            #[no_panic]
+            fn demo(&mut self, _s: &str) -> &[u8] {
+                &self.bytes[..]
+            }
+        }
+
+        fn main() {
+            let mut buffer = Buffer {
+                bytes: [0u8; 24],
+            };
+            println!("{:?}", buffer.demo(""));
+        }
+    }
+
+    mod test_ref_argument {
+        #[no_panic]
+        fn demo(ref i: i32) -> i32 {
+            *i
+        }
+
+        fn main() {
+            println!("{}", demo(0));
+        }
+    }
+
+    mod test_mut_argument {
+        #[no_panic]
+        fn demo(mut i: i32) -> i32 {
+            i += 1;
+            i
+        }
+
+        fn main() {
+            println!("{}", demo(0));
+        }
+    }
+
+    mod test_ref_mut_argument {
+        #[no_panic]
+        fn demo(ref mut i: i32) -> i32 {
+            *i += 1;
+            *i
+        }
+
+        fn main() {
+            println!("{}", demo(0));
+        }
+    }
+
+    mod test_borrow_from_mut_self {
+        struct S {
+            data: usize,
+        }
+
+        impl S {
+            #[no_panic]
+            fn get_mut(&mut self) -> &mut usize {
+                &mut self.data
+            }
+        }
+
+        fn main() {
+            let mut s = S { data: 0 };
+            println!("{}", s.get_mut());
+        }
+    }
+
+    mod test_self_in_vec {
+        struct S {
+            data: usize,
+        }
+
+        impl S {
+            #[no_panic]
+            fn get_mut(&mut self) -> Vec<usize> {
+                vec![self.data]
+            }
+        }
+
+        fn main() {
+            let mut s = S { data: 0 };
+            println!("{}", s.get_mut()[0]);
+        }
+    }
+
+    mod test_self_in_macro_containing_fn {
+        pub struct S {
+            data: usize,
+        }
+
+        macro_rules! emit {
+            ($($tt:tt)*) => {
+                $($tt)*
+            };
+        }
+
+        impl S {
+            #[no_panic]
+            fn get_mut(&mut self) -> usize {
+                let _ = emit!({
+                    impl S {
+                        pub fn f(self) {}
+                    }
+                });
+                self.data
+            }
+        }
+
+        fn main() {
+            let mut s = S { data: 0 };
+            println!("{}", s.get_mut());
+        }
+    }
+}
+
+assert_link_error! {
+    mod test_readme {
+        #[no_panic]
+        fn demo(s: &str) -> &str {
+            &s[1..]
+        }
+
+        fn main() {
+            println!("{}", demo("\u{1f980}input string"));
+        }
+    }
+}