diff --git a/.cargo_vcs_info.json b/.cargo_vcs_info.json
new file mode 100644
index 0000000..2499ccd
--- /dev/null
+++ b/.cargo_vcs_info.json
@@ -0,0 +1,5 @@
+{
+  "git": {
+    "sha1": "30668016aca6bd3b02c766e8347e0b4080d4c296"
+  }
+}
diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..fbd9642
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,4 @@
+target
+Cargo.lock
+
+/.idea/
diff --git a/Android.bp b/Android.bp
new file mode 100644
index 0000000..c83e2fa
--- /dev/null
+++ b/Android.bp
@@ -0,0 +1,14 @@
+// This file is generated by cargo2android.py.
+
+rust_library_host_rlib {
+    name: "libbitflags",
+    crate_name: "bitflags",
+    srcs: ["src/lib.rs"],
+    edition: "2015",
+    features: [
+        "default",
+    ],
+    flags: [
+        "--cfg bitflags_const_fn",
+    ],
+}
diff --git a/CHANGELOG.md b/CHANGELOG.md
new file mode 100644
index 0000000..0d49101
--- /dev/null
+++ b/CHANGELOG.md
@@ -0,0 +1,149 @@
+# 1.2.1
+
+- Remove extraneous `#[inline]` attributes ([#194])
+
+[#194]: https://github.com/bitflags/bitflags/pull/194
+
+# 1.2.0
+
+- Fix typo: {Lower, Upper}Exp - {Lower, Upper}Hex ([#183])
+
+- Add support for "unknown" bits ([#188])
+
+[#183]: https://github.com/rust-lang-nursery/bitflags/pull/183
+[#188]: https://github.com/rust-lang-nursery/bitflags/pull/188
+
+# 1.1.0
+
+This is a re-release of `1.0.5`, which was yanked due to a bug in the RLS.
+
+# 1.0.5
+
+- Use compiletest_rs flags supported by stable toolchain ([#171])
+
+- Put the user provided attributes first ([#173])
+
+- Make bitflags methods `const` on newer compilers ([#175])
+
+[#171]: https://github.com/rust-lang-nursery/bitflags/pull/171
+[#173]: https://github.com/rust-lang-nursery/bitflags/pull/173
+[#175]: https://github.com/rust-lang-nursery/bitflags/pull/175
+
+# 1.0.4
+
+- Support Rust 2018 style macro imports ([#165])
+
+  ```rust
+  use bitflags::bitflags;
+  ```
+
+[#165]: https://github.com/rust-lang-nursery/bitflags/pull/165
+
+# 1.0.3
+
+- Improve zero value flag handling and documentation ([#157])
+
+[#157]: https://github.com/rust-lang-nursery/bitflags/pull/157
+
+# 1.0.2
+
+- 30% improvement in compile time of bitflags crate ([#156])
+
+- Documentation improvements ([#153])
+
+- Implementation cleanup ([#149])
+
+[#156]: https://github.com/rust-lang-nursery/bitflags/pull/156
+[#153]: https://github.com/rust-lang-nursery/bitflags/pull/153
+[#149]: https://github.com/rust-lang-nursery/bitflags/pull/149
+
+# 1.0.1
+- Add support for `pub(restricted)` specifier on the bitflags struct ([#135])
+- Optimize performance of `all()` when called from a separate crate ([#136])
+
+[#135]: https://github.com/rust-lang-nursery/bitflags/pull/135
+[#136]: https://github.com/rust-lang-nursery/bitflags/pull/136
+
+# 1.0.0
+- **[breaking change]** Macro now generates [associated constants](https://doc.rust-lang.org/reference/items.html#associated-constants) ([#24])
+
+- **[breaking change]** Minimum supported version is Rust **1.20**, due to usage of associated constants
+
+- After being broken in 0.9, the `#[deprecated]` attribute is now supported again ([#112])
+
+- Other improvements to unit tests and documentation ([#106] and [#115])
+
+[#24]: https://github.com/rust-lang-nursery/bitflags/pull/24
+[#106]: https://github.com/rust-lang-nursery/bitflags/pull/106
+[#112]: https://github.com/rust-lang-nursery/bitflags/pull/112
+[#115]: https://github.com/rust-lang-nursery/bitflags/pull/115
+
+## How to update your code to use associated constants
+Assuming the following structure definition:
+```rust
+bitflags! {
+  struct Something: u8 {
+     const FOO = 0b01,
+     const BAR = 0b10
+  }
+}
+```
+In 0.9 and older you could do:
+```rust
+let x = FOO.bits | BAR.bits;
+```
+Now you must use:
+```rust
+let x = Something::FOO.bits | Something::BAR.bits;
+```
+
+# 0.9.1
+- Fix the implementation of `Formatting` traits when other formatting traits were present in scope ([#105])
+
+[#105]: https://github.com/rust-lang-nursery/bitflags/pull/105
+
+# 0.9.0
+- **[breaking change]** Use struct keyword instead of flags to define bitflag types ([#84])
+
+- **[breaking change]** Terminate const items with semicolons instead of commas ([#87])
+
+- Implement the `Hex`, `Octal`, and `Binary` formatting traits ([#86])
+
+- Printing an empty flag value with the `Debug` trait now prints "(empty)" instead of nothing ([#85])
+
+- The `bitflags!` macro can now be used inside of a fn body, to define a type local to that function ([#74])
+
+[#74]: https://github.com/rust-lang-nursery/bitflags/pull/74
+[#84]: https://github.com/rust-lang-nursery/bitflags/pull/84
+[#85]: https://github.com/rust-lang-nursery/bitflags/pull/85
+[#86]: https://github.com/rust-lang-nursery/bitflags/pull/86
+[#87]: https://github.com/rust-lang-nursery/bitflags/pull/87
+
+# 0.8.2
+- Update feature flag used when building bitflags as a dependency of the Rust toolchain
+
+# 0.8.1
+- Allow bitflags to be used as a dependency of the Rust toolchain
+
+# 0.8.0
+- Add support for the experimental `i128` and `u128` integer types ([#57])
+- Add set method: `flags.set(SOME_FLAG, true)` or `flags.set(SOME_FLAG, false)` ([#55])
+  This may break code that defines its own set method
+
+[#55]: https://github.com/rust-lang-nursery/bitflags/pull/55
+[#57]: https://github.com/rust-lang-nursery/bitflags/pull/57
+
+# 0.7.1
+*(yanked)*
+
+# 0.7.0
+- Implement the Extend trait ([#49])
+- Allow definitions inside the `bitflags!` macro to refer to items imported from other modules ([#51])
+
+[#49]: https://github.com/rust-lang-nursery/bitflags/pull/49
+[#51]: https://github.com/rust-lang-nursery/bitflags/pull/51
+
+# 0.6.0
+- The `no_std` feature was removed as it is now the default
+- The `assignment_operators` feature was remove as it is now enabled by default
+- Some clippy suggestions have been applied
diff --git a/CODE_OF_CONDUCT.md b/CODE_OF_CONDUCT.md
new file mode 100644
index 0000000..f7add90
--- /dev/null
+++ b/CODE_OF_CONDUCT.md
@@ -0,0 +1,73 @@
+# Contributor Covenant Code of Conduct
+
+## Our Pledge
+
+In the interest of fostering an open and welcoming environment, we as
+contributors and maintainers pledge to making participation in our project and
+our community a harassment-free experience for everyone, regardless of age, body
+size, disability, ethnicity, gender identity and expression, level of experience,
+education, socio-economic status, nationality, personal appearance, race,
+religion, or sexual identity and orientation.
+
+## Our Standards
+
+Examples of behavior that contributes to creating a positive environment
+include:
+
+* Using welcoming and inclusive language
+* Being respectful of differing viewpoints and experiences
+* Gracefully accepting constructive criticism
+* Focusing on what is best for the community
+* Showing empathy towards other community members
+
+Examples of unacceptable behavior by participants include:
+
+* The use of sexualized language or imagery and unwelcome sexual attention or
+  advances
+* Trolling, insulting/derogatory comments, and personal or political attacks
+* Public or private harassment
+* Publishing others' private information, such as a physical or electronic
+  address, without explicit permission
+* Other conduct which could reasonably be considered inappropriate in a
+  professional setting
+
+## Our Responsibilities
+
+Project maintainers are responsible for clarifying the standards of acceptable
+behavior and are expected to take appropriate and fair corrective action in
+response to any instances of unacceptable behavior.
+
+Project maintainers have the right and responsibility to remove, edit, or
+reject comments, commits, code, wiki edits, issues, and other contributions
+that are not aligned to this Code of Conduct, or to ban temporarily or
+permanently any contributor for other behaviors that they deem inappropriate,
+threatening, offensive, or harmful.
+
+## Scope
+
+This Code of Conduct applies both within project spaces and in public spaces
+when an individual is representing the project or its community. Examples of
+representing a project or community include using an official project e-mail
+address, posting via an official social media account, or acting as an appointed
+representative at an online or offline event. Representation of a project may be
+further defined and clarified by project maintainers.
+
+## Enforcement
+
+Instances of abusive, harassing, or otherwise unacceptable behavior may be
+reported by contacting the project team at coc@senaite.org. All
+complaints will be reviewed and investigated and will result in a response that
+is deemed necessary and appropriate to the circumstances. The project team is
+obligated to maintain confidentiality with regard to the reporter of an incident.
+Further details of specific enforcement policies may be posted separately.
+
+Project maintainers who do not follow or enforce the Code of Conduct in good
+faith may face temporary or permanent repercussions as determined by other
+members of the project's leadership.
+
+## Attribution
+
+This Code of Conduct is adapted from the [Contributor Covenant][homepage], version 1.4,
+available at https://www.contributor-covenant.org/version/1/4/code-of-conduct.html
+
+[homepage]: https://www.contributor-covenant.org
\ No newline at end of file
diff --git a/Cargo.toml b/Cargo.toml
new file mode 100644
index 0000000..b803644
--- /dev/null
+++ b/Cargo.toml
@@ -0,0 +1,34 @@
+# 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]
+name = "bitflags"
+version = "1.2.1"
+authors = ["The Rust Project Developers"]
+build = "build.rs"
+exclude = [".travis.yml", "appveyor.yml", "bors.toml"]
+description = "A macro to generate structures which behave like bitflags.\n"
+homepage = "https://github.com/bitflags/bitflags"
+documentation = "https://docs.rs/bitflags"
+readme = "README.md"
+keywords = ["bit", "bitmask", "bitflags", "flags"]
+categories = ["no-std"]
+license = "MIT/Apache-2.0"
+repository = "https://github.com/bitflags/bitflags"
+[package.metadata.docs.rs]
+features = ["example_generated"]
+
+[features]
+default = []
+example_generated = []
+[badges.travis-ci]
+repository = "bitflags/bitflags"
diff --git a/Cargo.toml.orig b/Cargo.toml.orig
new file mode 100644
index 0000000..afbe066
--- /dev/null
+++ b/Cargo.toml.orig
@@ -0,0 +1,37 @@
+[package]
+
+name = "bitflags"
+# NB: When modifying, also modify:
+#   1. html_root_url in lib.rs
+#   2. number in readme (for breaking changes)
+version = "1.2.1"
+authors = ["The Rust Project Developers"]
+license = "MIT/Apache-2.0"
+keywords = ["bit", "bitmask", "bitflags", "flags"]
+readme = "README.md"
+repository = "https://github.com/bitflags/bitflags"
+homepage = "https://github.com/bitflags/bitflags"
+documentation = "https://docs.rs/bitflags"
+categories = ["no-std"]
+description = """
+A macro to generate structures which behave like bitflags.
+"""
+exclude = [
+    ".travis.yml",
+    "appveyor.yml",
+    "bors.toml"
+]
+build = "build.rs"
+
+[badges]
+travis-ci = { repository = "bitflags/bitflags" }
+
+[features]
+default = []
+example_generated = []
+
+[package.metadata.docs.rs]
+features = [ "example_generated" ]
+
+[workspace]
+members = ["test_suite"]
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 @@
+                              Apache License
+                        Version 2.0, January 2004
+                     http://www.apache.org/licenses/
+
+TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
+
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+   "You" (or "Your") shall mean an individual or Legal Entity
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+
+5. Submission of Contributions. Unless You explicitly state otherwise,
+   any Contribution intentionally submitted for inclusion in the Work
+   by You to the Licensor shall be under the terms and conditions of
+   this License, without any additional terms or conditions.
+   Notwithstanding the above, nothing herein shall supersede or modify
+   the terms of any separate license agreement you may have executed
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+
+6. Trademarks. This License does not grant permission to use the trade
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+7. Disclaimer of Warranty. Unless required by applicable law or
+   agreed to in writing, Licensor provides the Work (and each
+   Contributor provides its Contributions) on an "AS IS" BASIS,
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+   whether in tort (including negligence), contract, or otherwise,
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+APPENDIX: How to apply the Apache License to your work.
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diff --git a/LICENSE-MIT b/LICENSE-MIT
new file mode 100644
index 0000000..39d4bdb
--- /dev/null
+++ b/LICENSE-MIT
@@ -0,0 +1,25 @@
+Copyright (c) 2014 The Rust Project Developers
+
+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
+CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR
+IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+DEALINGS IN THE SOFTWARE.
diff --git a/METADATA b/METADATA
new file mode 100644
index 0000000..ee6a075
--- /dev/null
+++ b/METADATA
@@ -0,0 +1,16 @@
+name: "bitflags"
+description:
+    "A Rust macro to generate structures which behave like a set of bitflags."
+
+third_party {
+  url {
+    type: HOMEPAGE
+    value: "https://crates.io/crates/bitflags"
+  }
+  url {
+    type: GIT
+    value: "https://github.com/bitflags/bitflags"
+  }
+  version: "1.2.1"
+  last_upgrade_date { year: 2019 month: 12 day: 12 }
+}
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/NOTICE b/NOTICE
new file mode 120000
index 0000000..7a694c9
--- /dev/null
+++ b/NOTICE
@@ -0,0 +1 @@
+LICENSE
\ No newline at end of file
diff --git a/README.md b/README.md
new file mode 100644
index 0000000..df12934
--- /dev/null
+++ b/README.md
@@ -0,0 +1,34 @@
+bitflags
+========
+
+[![Build Status](https://travis-ci.com/bitflags/bitflags.svg?branch=master)](https://travis-ci.com/bitflags/bitflags)
+[![Join the chat at https://gitter.im/bitflags/Lobby](https://badges.gitter.im/Join%20Chat.svg)](https://gitter.im/bitflags/Lobby?utm_source=badge&utm_medium=badge&utm_content=badge)
+[![Latest version](https://img.shields.io/crates/v/bitflags.svg)](https://crates.io/crates/bitflags)
+[![Documentation](https://docs.rs/bitflags/badge.svg)](https://docs.rs/bitflags)
+![Minimum rustc version](https://img.shields.io/badge/rustc-1.20+-yellow.svg)
+![License](https://img.shields.io/crates/l/bitflags.svg)
+
+A Rust macro to generate structures which behave like a set of bitflags
+
+- [Documentation](https://docs.rs/bitflags)
+- [Release notes](https://github.com/bitflags/bitflags/releases)
+
+## Usage
+
+Add this to your `Cargo.toml`:
+
+```toml
+[dependencies]
+bitflags = "1.0"
+```
+
+and this to your crate root:
+
+```rust
+#[macro_use]
+extern crate bitflags;
+```
+
+## Rust Version Support
+
+The minimum supported Rust version is 1.20 due to use of associated constants.
diff --git a/build.rs b/build.rs
new file mode 100644
index 0000000..985757a
--- /dev/null
+++ b/build.rs
@@ -0,0 +1,44 @@
+use std::env;
+use std::process::Command;
+use std::str::{self, FromStr};
+
+fn main(){
+    let minor = match rustc_minor_version() {
+        Some(minor) => minor,
+        None => return,
+    };
+
+    // const fn stabilized in Rust 1.31:
+    if minor >= 31 {
+        println!("cargo:rustc-cfg=bitflags_const_fn");
+    }
+}
+
+fn rustc_minor_version() -> Option<u32> {
+    let rustc = match env::var_os("RUSTC") {
+        Some(rustc) => rustc,
+        None => return None,
+    };
+
+    let output = match Command::new(rustc).arg("--version").output() {
+        Ok(output) => output,
+        Err(_) => return None,
+    };
+
+    let version = match str::from_utf8(&output.stdout) {
+        Ok(version) => version,
+        Err(_) => return None,
+    };
+
+    let mut pieces = version.split('.');
+    if pieces.next() != Some("rustc 1") {
+        return None;
+    }
+
+    let next = match pieces.next() {
+        Some(next) => next,
+        None => return None,
+    };
+
+    u32::from_str(next).ok()
+}
\ No newline at end of file
diff --git a/src/example_generated.rs b/src/example_generated.rs
new file mode 100644
index 0000000..cf188d9
--- /dev/null
+++ b/src/example_generated.rs
@@ -0,0 +1,14 @@
+//! This module shows an example of code generated by the macro. **IT MUST NOT BE USED OUTSIDE THIS
+//! CRATE**.
+
+bitflags! {
+    /// This is the same `Flags` struct defined in the [crate level example](../index.html#example).
+    /// Note that this struct is just for documentation purposes only, it must not be used outside
+    /// this crate.
+    pub struct Flags: u32 {
+        const A = 0b00000001;
+        const B = 0b00000010;
+        const C = 0b00000100;
+        const ABC = Self::A.bits | Self::B.bits | Self::C.bits;
+    }
+}
diff --git a/src/lib.rs b/src/lib.rs
new file mode 100644
index 0000000..3929b02
--- /dev/null
+++ b/src/lib.rs
@@ -0,0 +1,1430 @@
+// Copyright 2014 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+//! A typesafe bitmask flag generator useful for sets of C-style bitmask flags.
+//! It can be used for creating typesafe wrappers around C APIs.
+//!
+//! The `bitflags!` macro generates a `struct` that manages a set of flags. The
+//! flags should only be defined for integer types, otherwise unexpected type
+//! errors may occur at compile time.
+//!
+//! # Example
+//!
+//! ```
+//! #[macro_use]
+//! extern crate bitflags;
+//!
+//! bitflags! {
+//!     struct Flags: u32 {
+//!         const A = 0b00000001;
+//!         const B = 0b00000010;
+//!         const C = 0b00000100;
+//!         const ABC = Self::A.bits | Self::B.bits | Self::C.bits;
+//!     }
+//! }
+//!
+//! fn main() {
+//!     let e1 = Flags::A | Flags::C;
+//!     let e2 = Flags::B | Flags::C;
+//!     assert_eq!((e1 | e2), Flags::ABC);   // union
+//!     assert_eq!((e1 & e2), Flags::C);     // intersection
+//!     assert_eq!((e1 - e2), Flags::A);     // set difference
+//!     assert_eq!(!e2, Flags::A);           // set complement
+//! }
+//! ```
+//!
+//! See [`example_generated::Flags`](./example_generated/struct.Flags.html) for documentation of code
+//! generated by the above `bitflags!` expansion.
+//!
+//! The generated `struct`s can also be extended with type and trait
+//! implementations:
+//!
+//! ```
+//! #[macro_use]
+//! extern crate bitflags;
+//!
+//! use std::fmt;
+//!
+//! bitflags! {
+//!     struct Flags: u32 {
+//!         const A = 0b00000001;
+//!         const B = 0b00000010;
+//!     }
+//! }
+//!
+//! impl Flags {
+//!     pub fn clear(&mut self) {
+//!         self.bits = 0;  // The `bits` field can be accessed from within the
+//!                         // same module where the `bitflags!` macro was invoked.
+//!     }
+//! }
+//!
+//! impl fmt::Display for Flags {
+//!     fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+//!         write!(f, "hi!")
+//!     }
+//! }
+//!
+//! fn main() {
+//!     let mut flags = Flags::A | Flags::B;
+//!     flags.clear();
+//!     assert!(flags.is_empty());
+//!     assert_eq!(format!("{}", flags), "hi!");
+//!     assert_eq!(format!("{:?}", Flags::A | Flags::B), "A | B");
+//!     assert_eq!(format!("{:?}", Flags::B), "B");
+//! }
+//! ```
+//!
+//! # Visibility
+//!
+//! The generated struct and its associated flag constants are not exported
+//! out of the current module by default. A definition can be exported out of
+//! the current module by adding `pub` before `flags`:
+//!
+//! ```
+//! #[macro_use]
+//! extern crate bitflags;
+//!
+//! mod example {
+//!     bitflags! {
+//!         pub struct Flags1: u32 {
+//!             const A = 0b00000001;
+//!         }
+//!     }
+//!     bitflags! {
+//! #       pub
+//!         struct Flags2: u32 {
+//!             const B = 0b00000010;
+//!         }
+//!     }
+//! }
+//!
+//! fn main() {
+//!     let flag1 = example::Flags1::A;
+//!     let flag2 = example::Flags2::B; // error: const `B` is private
+//! }
+//! ```
+//!
+//! # Attributes
+//!
+//! Attributes can be attached to the generated `struct` by placing them
+//! before the `flags` keyword.
+//!
+//! # Trait implementations
+//!
+//! The `Copy`, `Clone`, `PartialEq`, `Eq`, `PartialOrd`, `Ord` and `Hash`
+//! traits automatically derived for the `struct` using the `derive` attribute.
+//! Additional traits can be derived by providing an explicit `derive`
+//! attribute on `flags`.
+//!
+//! The `Extend` and `FromIterator` traits are implemented for the `struct`,
+//! too: `Extend` adds the union of the instances of the `struct` iterated over,
+//! while `FromIterator` calculates the union.
+//!
+//! The `Binary`, `Debug`, `LowerHex`, `Octal` and `UpperHex` trait is also
+//! implemented by displaying the bits value of the internal struct.
+//!
+//! ## Operators
+//!
+//! The following operator traits are implemented for the generated `struct`:
+//!
+//! - `BitOr` and `BitOrAssign`: union
+//! - `BitAnd` and `BitAndAssign`: intersection
+//! - `BitXor` and `BitXorAssign`: toggle
+//! - `Sub` and `SubAssign`: set difference
+//! - `Not`: set complement
+//!
+//! # Methods
+//!
+//! The following methods are defined for the generated `struct`:
+//!
+//! - `empty`: an empty set of flags
+//! - `all`: the set of all defined flags
+//! - `bits`: the raw value of the flags currently stored
+//! - `from_bits`: convert from underlying bit representation, unless that
+//!                representation contains bits that do not correspond to a
+//!                defined flag
+//! - `from_bits_truncate`: convert from underlying bit representation, dropping
+//!                         any bits that do not correspond to defined flags
+//! - `from_bits_unchecked`: convert from underlying bit representation, keeping
+//!                          all bits (even those not corresponding to defined
+//!                          flags)
+//! - `is_empty`: `true` if no flags are currently stored
+//! - `is_all`: `true` if currently set flags exactly equal all defined flags
+//! - `intersects`: `true` if there are flags common to both `self` and `other`
+//! - `contains`: `true` all of the flags in `other` are contained within `self`
+//! - `insert`: inserts the specified flags in-place
+//! - `remove`: removes the specified flags in-place
+//! - `toggle`: the specified flags will be inserted if not present, and removed
+//!             if they are.
+//! - `set`: inserts or removes the specified flags depending on the passed value
+//!
+//! ## Default
+//!
+//! The `Default` trait is not automatically implemented for the generated struct.
+//!
+//! If your default value is equal to `0` (which is the same value as calling `empty()`
+//! on the generated struct), you can simply derive `Default`:
+//!
+//! ```
+//! #[macro_use]
+//! extern crate bitflags;
+//!
+//! bitflags! {
+//!     // Results in default value with bits: 0
+//!     #[derive(Default)]
+//!     struct Flags: u32 {
+//!         const A = 0b00000001;
+//!         const B = 0b00000010;
+//!         const C = 0b00000100;
+//!     }
+//! }
+//!
+//! fn main() {
+//!     let derived_default: Flags = Default::default();
+//!     assert_eq!(derived_default.bits(), 0);
+//! }
+//! ```
+//!
+//! If your default value is not equal to `0` you need to implement `Default` yourself:
+//!
+//! ```
+//! #[macro_use]
+//! extern crate bitflags;
+//!
+//! bitflags! {
+//!     struct Flags: u32 {
+//!         const A = 0b00000001;
+//!         const B = 0b00000010;
+//!         const C = 0b00000100;
+//!     }
+//! }
+//!
+//! // explicit `Default` implementation
+//! impl Default for Flags {
+//!     fn default() -> Flags {
+//!         Flags::A | Flags::C
+//!     }
+//! }
+//!
+//! fn main() {
+//!     let implemented_default: Flags = Default::default();
+//!     assert_eq!(implemented_default, (Flags::A | Flags::C));
+//! }
+//! ```
+//!
+//! # Zero Flags
+//!
+//! Flags with a value equal to zero will have some strange behavior that one should be aware of.
+//!
+//! ```
+//! #[macro_use]
+//! extern crate bitflags;
+//!
+//! bitflags! {
+//!     struct Flags: u32 {
+//!         const NONE = 0b00000000;
+//!         const SOME = 0b00000001;
+//!     }
+//! }
+//!
+//! fn main() {
+//!     let empty = Flags::empty();
+//!     let none = Flags::NONE;
+//!     let some = Flags::SOME;
+//!
+//!     // Zero flags are treated as always present
+//!     assert!(empty.contains(Flags::NONE));
+//!     assert!(none.contains(Flags::NONE));
+//!     assert!(some.contains(Flags::NONE));
+//!
+//!     // Zero flags will be ignored when testing for emptiness
+//!     assert!(none.is_empty());
+//! }
+//! ```
+
+#![no_std]
+#![doc(html_root_url = "https://docs.rs/bitflags/1.2.1")]
+
+#[cfg(test)]
+#[macro_use]
+extern crate std;
+
+// Re-export libcore using an alias so that the macros can work without
+// requiring `extern crate core` downstream.
+#[doc(hidden)]
+pub extern crate core as _core;
+
+/// The macro used to generate the flag structure.
+///
+/// See the [crate level docs](../bitflags/index.html) for complete documentation.
+///
+/// # Example
+///
+/// ```
+/// #[macro_use]
+/// extern crate bitflags;
+///
+/// bitflags! {
+///     struct Flags: u32 {
+///         const A = 0b00000001;
+///         const B = 0b00000010;
+///         const C = 0b00000100;
+///         const ABC = Self::A.bits | Self::B.bits | Self::C.bits;
+///     }
+/// }
+///
+/// fn main() {
+///     let e1 = Flags::A | Flags::C;
+///     let e2 = Flags::B | Flags::C;
+///     assert_eq!((e1 | e2), Flags::ABC);   // union
+///     assert_eq!((e1 & e2), Flags::C);     // intersection
+///     assert_eq!((e1 - e2), Flags::A);     // set difference
+///     assert_eq!(!e2, Flags::A);           // set complement
+/// }
+/// ```
+///
+/// The generated `struct`s can also be extended with type and trait
+/// implementations:
+///
+/// ```
+/// #[macro_use]
+/// extern crate bitflags;
+///
+/// use std::fmt;
+///
+/// bitflags! {
+///     struct Flags: u32 {
+///         const A = 0b00000001;
+///         const B = 0b00000010;
+///     }
+/// }
+///
+/// impl Flags {
+///     pub fn clear(&mut self) {
+///         self.bits = 0;  // The `bits` field can be accessed from within the
+///                         // same module where the `bitflags!` macro was invoked.
+///     }
+/// }
+///
+/// impl fmt::Display for Flags {
+///     fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+///         write!(f, "hi!")
+///     }
+/// }
+///
+/// fn main() {
+///     let mut flags = Flags::A | Flags::B;
+///     flags.clear();
+///     assert!(flags.is_empty());
+///     assert_eq!(format!("{}", flags), "hi!");
+///     assert_eq!(format!("{:?}", Flags::A | Flags::B), "A | B");
+///     assert_eq!(format!("{:?}", Flags::B), "B");
+/// }
+/// ```
+#[macro_export(local_inner_macros)]
+macro_rules! bitflags {
+    (
+        $(#[$outer:meta])*
+        pub struct $BitFlags:ident: $T:ty {
+            $(
+                $(#[$inner:ident $($args:tt)*])*
+                const $Flag:ident = $value:expr;
+            )+
+        }
+    ) => {
+        __bitflags! {
+            $(#[$outer])*
+            (pub) $BitFlags: $T {
+                $(
+                    $(#[$inner $($args)*])*
+                    $Flag = $value;
+                )+
+            }
+        }
+    };
+    (
+        $(#[$outer:meta])*
+        struct $BitFlags:ident: $T:ty {
+            $(
+                $(#[$inner:ident $($args:tt)*])*
+                const $Flag:ident = $value:expr;
+            )+
+        }
+    ) => {
+        __bitflags! {
+            $(#[$outer])*
+            () $BitFlags: $T {
+                $(
+                    $(#[$inner $($args)*])*
+                    $Flag = $value;
+                )+
+            }
+        }
+    };
+    (
+        $(#[$outer:meta])*
+        pub ($($vis:tt)+) struct $BitFlags:ident: $T:ty {
+            $(
+                $(#[$inner:ident $($args:tt)*])*
+                const $Flag:ident = $value:expr;
+            )+
+        }
+    ) => {
+        __bitflags! {
+            $(#[$outer])*
+            (pub ($($vis)+)) $BitFlags: $T {
+                $(
+                    $(#[$inner $($args)*])*
+                    $Flag = $value;
+                )+
+            }
+        }
+    };
+}
+
+#[macro_export(local_inner_macros)]
+#[doc(hidden)]
+macro_rules! __bitflags {
+    (
+        $(#[$outer:meta])*
+        ($($vis:tt)*) $BitFlags:ident: $T:ty {
+            $(
+                $(#[$inner:ident $($args:tt)*])*
+                $Flag:ident = $value:expr;
+            )+
+        }
+    ) => {
+        $(#[$outer])*
+        #[derive(Copy, PartialEq, Eq, Clone, PartialOrd, Ord, Hash)]
+        $($vis)* struct $BitFlags {
+            bits: $T,
+        }
+
+        __impl_bitflags! {
+            $BitFlags: $T {
+                $(
+                    $(#[$inner $($args)*])*
+                    $Flag = $value;
+                )+
+            }
+        }
+    };
+}
+
+#[macro_export(local_inner_macros)]
+#[doc(hidden)]
+#[cfg(bitflags_const_fn)]
+macro_rules! __fn_bitflags {
+    (
+        $(# $attr_args:tt)*
+        const fn $($item:tt)*
+    ) => {
+        $(# $attr_args)*
+        const fn $($item)*
+    };
+    (
+        $(# $attr_args:tt)*
+        pub const fn $($item:tt)*
+    ) => {
+        $(# $attr_args)*
+        pub const fn $($item)*
+    };
+    (
+        $(# $attr_args:tt)*
+        pub const unsafe fn $($item:tt)*
+    ) => {
+        $(# $attr_args)*
+        pub const unsafe fn $($item)*
+    };
+}
+
+#[macro_export(local_inner_macros)]
+#[doc(hidden)]
+#[cfg(not(bitflags_const_fn))]
+macro_rules! __fn_bitflags {
+    (
+        $(# $attr_args:tt)*
+        const fn $($item:tt)*
+    ) => {
+        $(# $attr_args)*
+        fn $($item)*
+    };
+    (
+        $(# $attr_args:tt)*
+        pub const fn $($item:tt)*
+    ) => {
+        $(# $attr_args)*
+        pub fn $($item)*
+    };
+    (
+        $(# $attr_args:tt)*
+        pub const unsafe fn $($item:tt)*
+    ) => {
+        $(# $attr_args)*
+        pub unsafe fn $($item)*
+    };
+}
+
+#[macro_export(local_inner_macros)]
+#[doc(hidden)]
+macro_rules! __impl_bitflags {
+    (
+        $BitFlags:ident: $T:ty {
+            $(
+                $(#[$attr:ident $($args:tt)*])*
+                $Flag:ident = $value:expr;
+            )+
+        }
+    ) => {
+        impl $crate::_core::fmt::Debug for $BitFlags {
+            fn fmt(&self, f: &mut $crate::_core::fmt::Formatter) -> $crate::_core::fmt::Result {
+                // This convoluted approach is to handle #[cfg]-based flag
+                // omission correctly. For example it needs to support:
+                //
+                //    #[cfg(unix)] const A: Flag = /* ... */;
+                //    #[cfg(windows)] const B: Flag = /* ... */;
+
+                // Unconditionally define a check for every flag, even disabled
+                // ones.
+                #[allow(non_snake_case)]
+                trait __BitFlags {
+                    $(
+                        #[inline]
+                        fn $Flag(&self) -> bool { false }
+                    )+
+                }
+
+                // Conditionally override the check for just those flags that
+                // are not #[cfg]ed away.
+                impl __BitFlags for $BitFlags {
+                    $(
+                        __impl_bitflags! {
+                            #[allow(deprecated)]
+                            #[inline]
+                            $(? #[$attr $($args)*])*
+                            fn $Flag(&self) -> bool {
+                                if Self::$Flag.bits == 0 && self.bits != 0 {
+                                    false
+                                } else {
+                                    self.bits & Self::$Flag.bits == Self::$Flag.bits
+                                }
+                            }
+                        }
+                    )+
+                }
+
+                let mut first = true;
+                $(
+                    if <$BitFlags as __BitFlags>::$Flag(self) {
+                        if !first {
+                            f.write_str(" | ")?;
+                        }
+                        first = false;
+                        f.write_str(__bitflags_stringify!($Flag))?;
+                    }
+                )+
+                let extra_bits = self.bits & !$BitFlags::all().bits();
+                if extra_bits != 0 {
+                    if !first {
+                        f.write_str(" | ")?;
+                    }
+                    first = false;
+                    f.write_str("0x")?;
+                    $crate::_core::fmt::LowerHex::fmt(&extra_bits, f)?;
+                }
+                if first {
+                    f.write_str("(empty)")?;
+                }
+                Ok(())
+            }
+        }
+        impl $crate::_core::fmt::Binary for $BitFlags {
+            fn fmt(&self, f: &mut $crate::_core::fmt::Formatter) -> $crate::_core::fmt::Result {
+                $crate::_core::fmt::Binary::fmt(&self.bits, f)
+            }
+        }
+        impl $crate::_core::fmt::Octal for $BitFlags {
+            fn fmt(&self, f: &mut $crate::_core::fmt::Formatter) -> $crate::_core::fmt::Result {
+                $crate::_core::fmt::Octal::fmt(&self.bits, f)
+            }
+        }
+        impl $crate::_core::fmt::LowerHex for $BitFlags {
+            fn fmt(&self, f: &mut $crate::_core::fmt::Formatter) -> $crate::_core::fmt::Result {
+                $crate::_core::fmt::LowerHex::fmt(&self.bits, f)
+            }
+        }
+        impl $crate::_core::fmt::UpperHex for $BitFlags {
+            fn fmt(&self, f: &mut $crate::_core::fmt::Formatter) -> $crate::_core::fmt::Result {
+                $crate::_core::fmt::UpperHex::fmt(&self.bits, f)
+            }
+        }
+
+        #[allow(dead_code)]
+        impl $BitFlags {
+            $(
+                $(#[$attr $($args)*])*
+                pub const $Flag: $BitFlags = $BitFlags { bits: $value };
+            )+
+
+            __fn_bitflags! {
+                /// Returns an empty set of flags
+                #[inline]
+                pub const fn empty() -> $BitFlags {
+                    $BitFlags { bits: 0 }
+                }
+            }
+
+            __fn_bitflags! {
+                /// Returns the set containing all flags.
+                #[inline]
+                pub const fn all() -> $BitFlags {
+                    // See `Debug::fmt` for why this approach is taken.
+                    #[allow(non_snake_case)]
+                    trait __BitFlags {
+                        $(
+                            const $Flag: $T = 0;
+                        )+
+                    }
+                    impl __BitFlags for $BitFlags {
+                        $(
+                            __impl_bitflags! {
+                                #[allow(deprecated)]
+                                $(? #[$attr $($args)*])*
+                                const $Flag: $T = Self::$Flag.bits;
+                            }
+                        )+
+                    }
+                    $BitFlags { bits: $(<$BitFlags as __BitFlags>::$Flag)|+ }
+                }
+            }
+
+            __fn_bitflags! {
+                /// Returns the raw value of the flags currently stored.
+                #[inline]
+                pub const fn bits(&self) -> $T {
+                    self.bits
+                }
+            }
+
+            /// Convert from underlying bit representation, unless that
+            /// representation contains bits that do not correspond to a flag.
+            #[inline]
+            pub fn from_bits(bits: $T) -> $crate::_core::option::Option<$BitFlags> {
+                if (bits & !$BitFlags::all().bits()) == 0 {
+                    $crate::_core::option::Option::Some($BitFlags { bits })
+                } else {
+                    $crate::_core::option::Option::None
+                }
+            }
+
+            __fn_bitflags! {
+                /// Convert from underlying bit representation, dropping any bits
+                /// that do not correspond to flags.
+                #[inline]
+                pub const fn from_bits_truncate(bits: $T) -> $BitFlags {
+                    $BitFlags { bits: bits & $BitFlags::all().bits }
+                }
+            }
+
+            __fn_bitflags! {
+                /// Convert from underlying bit representation, preserving all
+                /// bits (even those not corresponding to a defined flag).
+                #[inline]
+                pub const unsafe fn from_bits_unchecked(bits: $T) -> $BitFlags {
+                    $BitFlags { bits }
+                }
+            }
+
+            __fn_bitflags! {
+                /// Returns `true` if no flags are currently stored.
+                #[inline]
+                pub const fn is_empty(&self) -> bool {
+                    self.bits() == $BitFlags::empty().bits()
+                }
+            }
+
+            __fn_bitflags! {
+                /// Returns `true` if all flags are currently set.
+                #[inline]
+                pub const fn is_all(&self) -> bool {
+                    self.bits == $BitFlags::all().bits
+                }
+            }
+
+            __fn_bitflags! {
+                /// Returns `true` if there are flags common to both `self` and `other`.
+                #[inline]
+                pub const fn intersects(&self, other: $BitFlags) -> bool {
+                    !$BitFlags{ bits: self.bits & other.bits}.is_empty()
+                }
+            }
+
+            __fn_bitflags! {
+                /// Returns `true` all of the flags in `other` are contained within `self`.
+                #[inline]
+                pub const fn contains(&self, other: $BitFlags) -> bool {
+                    (self.bits & other.bits) == other.bits
+                }
+            }
+
+            /// Inserts the specified flags in-place.
+            #[inline]
+            pub fn insert(&mut self, other: $BitFlags) {
+                self.bits |= other.bits;
+            }
+
+            /// Removes the specified flags in-place.
+            #[inline]
+            pub fn remove(&mut self, other: $BitFlags) {
+                self.bits &= !other.bits;
+            }
+
+            /// Toggles the specified flags in-place.
+            #[inline]
+            pub fn toggle(&mut self, other: $BitFlags) {
+                self.bits ^= other.bits;
+            }
+
+            /// Inserts or removes the specified flags depending on the passed value.
+            #[inline]
+            pub fn set(&mut self, other: $BitFlags, value: bool) {
+                if value {
+                    self.insert(other);
+                } else {
+                    self.remove(other);
+                }
+            }
+        }
+
+        impl $crate::_core::ops::BitOr for $BitFlags {
+            type Output = $BitFlags;
+
+            /// Returns the union of the two sets of flags.
+            #[inline]
+            fn bitor(self, other: $BitFlags) -> $BitFlags {
+                $BitFlags { bits: self.bits | other.bits }
+            }
+        }
+
+        impl $crate::_core::ops::BitOrAssign for $BitFlags {
+
+            /// Adds the set of flags.
+            #[inline]
+            fn bitor_assign(&mut self, other: $BitFlags) {
+                self.bits |= other.bits;
+            }
+        }
+
+        impl $crate::_core::ops::BitXor for $BitFlags {
+            type Output = $BitFlags;
+
+            /// Returns the left flags, but with all the right flags toggled.
+            #[inline]
+            fn bitxor(self, other: $BitFlags) -> $BitFlags {
+                $BitFlags { bits: self.bits ^ other.bits }
+            }
+        }
+
+        impl $crate::_core::ops::BitXorAssign for $BitFlags {
+
+            /// Toggles the set of flags.
+            #[inline]
+            fn bitxor_assign(&mut self, other: $BitFlags) {
+                self.bits ^= other.bits;
+            }
+        }
+
+        impl $crate::_core::ops::BitAnd for $BitFlags {
+            type Output = $BitFlags;
+
+            /// Returns the intersection between the two sets of flags.
+            #[inline]
+            fn bitand(self, other: $BitFlags) -> $BitFlags {
+                $BitFlags { bits: self.bits & other.bits }
+            }
+        }
+
+        impl $crate::_core::ops::BitAndAssign for $BitFlags {
+
+            /// Disables all flags disabled in the set.
+            #[inline]
+            fn bitand_assign(&mut self, other: $BitFlags) {
+                self.bits &= other.bits;
+            }
+        }
+
+        impl $crate::_core::ops::Sub for $BitFlags {
+            type Output = $BitFlags;
+
+            /// Returns the set difference of the two sets of flags.
+            #[inline]
+            fn sub(self, other: $BitFlags) -> $BitFlags {
+                $BitFlags { bits: self.bits & !other.bits }
+            }
+        }
+
+        impl $crate::_core::ops::SubAssign for $BitFlags {
+
+            /// Disables all flags enabled in the set.
+            #[inline]
+            fn sub_assign(&mut self, other: $BitFlags) {
+                self.bits &= !other.bits;
+            }
+        }
+
+        impl $crate::_core::ops::Not for $BitFlags {
+            type Output = $BitFlags;
+
+            /// Returns the complement of this set of flags.
+            #[inline]
+            fn not(self) -> $BitFlags {
+                $BitFlags { bits: !self.bits } & $BitFlags::all()
+            }
+        }
+
+        impl $crate::_core::iter::Extend<$BitFlags> for $BitFlags {
+            fn extend<T: $crate::_core::iter::IntoIterator<Item=$BitFlags>>(&mut self, iterator: T) {
+                for item in iterator {
+                    self.insert(item)
+                }
+            }
+        }
+
+        impl $crate::_core::iter::FromIterator<$BitFlags> for $BitFlags {
+            fn from_iter<T: $crate::_core::iter::IntoIterator<Item=$BitFlags>>(iterator: T) -> $BitFlags {
+                let mut result = Self::empty();
+                result.extend(iterator);
+                result
+            }
+        }
+    };
+
+    // Every attribute that the user writes on a const is applied to the
+    // corresponding const that we generate, but within the implementation of
+    // Debug and all() we want to ignore everything but #[cfg] attributes. In
+    // particular, including a #[deprecated] attribute on those items would fail
+    // to compile.
+    // https://github.com/bitflags/bitflags/issues/109
+    //
+    // Input:
+    //
+    //     ? #[cfg(feature = "advanced")]
+    //     ? #[deprecated(note = "Use somthing else.")]
+    //     ? #[doc = r"High quality documentation."]
+    //     fn f() -> i32 { /* ... */ }
+    //
+    // Output:
+    //
+    //     #[cfg(feature = "advanced")]
+    //     fn f() -> i32 { /* ... */ }
+    (
+        $(#[$filtered:meta])*
+        ? #[cfg $($cfgargs:tt)*]
+        $(? #[$rest:ident $($restargs:tt)*])*
+        fn $($item:tt)*
+    ) => {
+        __impl_bitflags! {
+            $(#[$filtered])*
+            #[cfg $($cfgargs)*]
+            $(? #[$rest $($restargs)*])*
+            fn $($item)*
+        }
+    };
+    (
+        $(#[$filtered:meta])*
+        // $next != `cfg`
+        ? #[$next:ident $($nextargs:tt)*]
+        $(? #[$rest:ident $($restargs:tt)*])*
+        fn $($item:tt)*
+    ) => {
+        __impl_bitflags! {
+            $(#[$filtered])*
+            // $next filtered out
+            $(? #[$rest $($restargs)*])*
+            fn $($item)*
+        }
+    };
+    (
+        $(#[$filtered:meta])*
+        fn $($item:tt)*
+    ) => {
+        $(#[$filtered])*
+        fn $($item)*
+    };
+
+    // Every attribute that the user writes on a const is applied to the
+    // corresponding const that we generate, but within the implementation of
+    // Debug and all() we want to ignore everything but #[cfg] attributes. In
+    // particular, including a #[deprecated] attribute on those items would fail
+    // to compile.
+    // https://github.com/bitflags/bitflags/issues/109
+    //
+    // const version
+    //
+    // Input:
+    //
+    //     ? #[cfg(feature = "advanced")]
+    //     ? #[deprecated(note = "Use somthing else.")]
+    //     ? #[doc = r"High quality documentation."]
+    //     const f: i32 { /* ... */ }
+    //
+    // Output:
+    //
+    //     #[cfg(feature = "advanced")]
+    //     const f: i32 { /* ... */ }
+    (
+        $(#[$filtered:meta])*
+        ? #[cfg $($cfgargs:tt)*]
+        $(? #[$rest:ident $($restargs:tt)*])*
+        const $($item:tt)*
+    ) => {
+        __impl_bitflags! {
+            $(#[$filtered])*
+            #[cfg $($cfgargs)*]
+            $(? #[$rest $($restargs)*])*
+            const $($item)*
+        }
+    };
+    (
+        $(#[$filtered:meta])*
+        // $next != `cfg`
+        ? #[$next:ident $($nextargs:tt)*]
+        $(? #[$rest:ident $($restargs:tt)*])*
+        const $($item:tt)*
+    ) => {
+        __impl_bitflags! {
+            $(#[$filtered])*
+            // $next filtered out
+            $(? #[$rest $($restargs)*])*
+            const $($item)*
+        }
+    };
+    (
+        $(#[$filtered:meta])*
+        const $($item:tt)*
+    ) => {
+        $(#[$filtered])*
+        const $($item)*
+    };
+}
+
+// Same as std::stringify but callable from __impl_bitflags, which needs to use
+// local_inner_macros so can only directly call macros from this crate.
+#[macro_export]
+#[doc(hidden)]
+macro_rules! __bitflags_stringify {
+    ($s:ident) => {
+        stringify!($s)
+    };
+}
+
+#[cfg(feature = "example_generated")]
+pub mod example_generated;
+
+#[cfg(test)]
+mod tests {
+    use std::collections::hash_map::DefaultHasher;
+    use std::hash::{Hash, Hasher};
+
+    bitflags! {
+        #[doc = "> The first principle is that you must not fool yourself — and"]
+        #[doc = "> you are the easiest person to fool."]
+        #[doc = "> "]
+        #[doc = "> - Richard Feynman"]
+        struct Flags: u32 {
+            const A = 0b00000001;
+            #[doc = "<pcwalton> macros are way better at generating code than trans is"]
+            const B = 0b00000010;
+            const C = 0b00000100;
+            #[doc = "* cmr bed"]
+            #[doc = "* strcat table"]
+            #[doc = "<strcat> wait what?"]
+            const ABC = Self::A.bits | Self::B.bits | Self::C.bits;
+        }
+    }
+
+    bitflags! {
+        struct _CfgFlags: u32 {
+            #[cfg(unix)]
+            const _CFG_A = 0b01;
+            #[cfg(windows)]
+            const _CFG_B = 0b01;
+            #[cfg(unix)]
+            const _CFG_C = Self::_CFG_A.bits | 0b10;
+        }
+    }
+
+    bitflags! {
+        struct AnotherSetOfFlags: i8 {
+            const ANOTHER_FLAG = -1_i8;
+        }
+    }
+
+    bitflags! {
+        struct LongFlags: u32 {
+            const LONG_A = 0b1111111111111111;
+        }
+    }
+
+    #[test]
+    fn test_bits() {
+        assert_eq!(Flags::empty().bits(), 0b00000000);
+        assert_eq!(Flags::A.bits(), 0b00000001);
+        assert_eq!(Flags::ABC.bits(), 0b00000111);
+
+        assert_eq!(AnotherSetOfFlags::empty().bits(), 0b00);
+        assert_eq!(AnotherSetOfFlags::ANOTHER_FLAG.bits(), !0_i8);
+    }
+
+    #[test]
+    fn test_from_bits() {
+        assert_eq!(Flags::from_bits(0), Some(Flags::empty()));
+        assert_eq!(Flags::from_bits(0b1), Some(Flags::A));
+        assert_eq!(Flags::from_bits(0b10), Some(Flags::B));
+        assert_eq!(Flags::from_bits(0b11), Some(Flags::A | Flags::B));
+        assert_eq!(Flags::from_bits(0b1000), None);
+
+        assert_eq!(
+            AnotherSetOfFlags::from_bits(!0_i8),
+            Some(AnotherSetOfFlags::ANOTHER_FLAG)
+        );
+    }
+
+    #[test]
+    fn test_from_bits_truncate() {
+        assert_eq!(Flags::from_bits_truncate(0), Flags::empty());
+        assert_eq!(Flags::from_bits_truncate(0b1), Flags::A);
+        assert_eq!(Flags::from_bits_truncate(0b10), Flags::B);
+        assert_eq!(Flags::from_bits_truncate(0b11), (Flags::A | Flags::B));
+        assert_eq!(Flags::from_bits_truncate(0b1000), Flags::empty());
+        assert_eq!(Flags::from_bits_truncate(0b1001), Flags::A);
+
+        assert_eq!(
+            AnotherSetOfFlags::from_bits_truncate(0_i8),
+            AnotherSetOfFlags::empty()
+        );
+    }
+
+    #[test]
+    fn test_from_bits_unchecked() {
+        let extra = unsafe { Flags::from_bits_unchecked(0b1000) };
+        assert_eq!(unsafe { Flags::from_bits_unchecked(0) }, Flags::empty());
+        assert_eq!(unsafe { Flags::from_bits_unchecked(0b1) }, Flags::A);
+        assert_eq!(unsafe { Flags::from_bits_unchecked(0b10) }, Flags::B);
+        assert_eq!(unsafe { Flags::from_bits_unchecked(0b11) }, (Flags::A | Flags::B));
+        assert_eq!(unsafe { Flags::from_bits_unchecked(0b1000) }, (extra | Flags::empty()));
+        assert_eq!(unsafe { Flags::from_bits_unchecked(0b1001) }, (extra | Flags::A));
+    }
+
+    #[test]
+    fn test_is_empty() {
+        assert!(Flags::empty().is_empty());
+        assert!(!Flags::A.is_empty());
+        assert!(!Flags::ABC.is_empty());
+
+        assert!(!AnotherSetOfFlags::ANOTHER_FLAG.is_empty());
+    }
+
+    #[test]
+    fn test_is_all() {
+        assert!(Flags::all().is_all());
+        assert!(!Flags::A.is_all());
+        assert!(Flags::ABC.is_all());
+
+        assert!(AnotherSetOfFlags::ANOTHER_FLAG.is_all());
+    }
+
+    #[test]
+    fn test_two_empties_do_not_intersect() {
+        let e1 = Flags::empty();
+        let e2 = Flags::empty();
+        assert!(!e1.intersects(e2));
+
+        assert!(AnotherSetOfFlags::ANOTHER_FLAG.intersects(AnotherSetOfFlags::ANOTHER_FLAG));
+    }
+
+    #[test]
+    fn test_empty_does_not_intersect_with_full() {
+        let e1 = Flags::empty();
+        let e2 = Flags::ABC;
+        assert!(!e1.intersects(e2));
+    }
+
+    #[test]
+    fn test_disjoint_intersects() {
+        let e1 = Flags::A;
+        let e2 = Flags::B;
+        assert!(!e1.intersects(e2));
+    }
+
+    #[test]
+    fn test_overlapping_intersects() {
+        let e1 = Flags::A;
+        let e2 = Flags::A | Flags::B;
+        assert!(e1.intersects(e2));
+    }
+
+    #[test]
+    fn test_contains() {
+        let e1 = Flags::A;
+        let e2 = Flags::A | Flags::B;
+        assert!(!e1.contains(e2));
+        assert!(e2.contains(e1));
+        assert!(Flags::ABC.contains(e2));
+
+        assert!(AnotherSetOfFlags::ANOTHER_FLAG.contains(AnotherSetOfFlags::ANOTHER_FLAG));
+    }
+
+    #[test]
+    fn test_insert() {
+        let mut e1 = Flags::A;
+        let e2 = Flags::A | Flags::B;
+        e1.insert(e2);
+        assert_eq!(e1, e2);
+
+        let mut e3 = AnotherSetOfFlags::empty();
+        e3.insert(AnotherSetOfFlags::ANOTHER_FLAG);
+        assert_eq!(e3, AnotherSetOfFlags::ANOTHER_FLAG);
+    }
+
+    #[test]
+    fn test_remove() {
+        let mut e1 = Flags::A | Flags::B;
+        let e2 = Flags::A | Flags::C;
+        e1.remove(e2);
+        assert_eq!(e1, Flags::B);
+
+        let mut e3 = AnotherSetOfFlags::ANOTHER_FLAG;
+        e3.remove(AnotherSetOfFlags::ANOTHER_FLAG);
+        assert_eq!(e3, AnotherSetOfFlags::empty());
+    }
+
+    #[test]
+    fn test_operators() {
+        let e1 = Flags::A | Flags::C;
+        let e2 = Flags::B | Flags::C;
+        assert_eq!((e1 | e2), Flags::ABC); // union
+        assert_eq!((e1 & e2), Flags::C); // intersection
+        assert_eq!((e1 - e2), Flags::A); // set difference
+        assert_eq!(!e2, Flags::A); // set complement
+        assert_eq!(e1 ^ e2, Flags::A | Flags::B); // toggle
+        let mut e3 = e1;
+        e3.toggle(e2);
+        assert_eq!(e3, Flags::A | Flags::B);
+
+        let mut m4 = AnotherSetOfFlags::empty();
+        m4.toggle(AnotherSetOfFlags::empty());
+        assert_eq!(m4, AnotherSetOfFlags::empty());
+    }
+
+    #[test]
+    fn test_operators_unchecked() {
+        let extra = unsafe { Flags::from_bits_unchecked(0b1000) };
+        let e1 = Flags::A | Flags::C | extra;
+        let e2 = Flags::B | Flags::C;
+        assert_eq!((e1 | e2), (Flags::ABC | extra)); // union
+        assert_eq!((e1 & e2), Flags::C); // intersection
+        assert_eq!((e1 - e2), (Flags::A | extra)); // set difference
+        assert_eq!(!e2, Flags::A); // set complement
+        assert_eq!(!e1, Flags::B); // set complement
+        assert_eq!(e1 ^ e2, Flags::A | Flags::B | extra); // toggle
+        let mut e3 = e1;
+        e3.toggle(e2);
+        assert_eq!(e3, Flags::A | Flags::B | extra);
+    }
+
+    #[test]
+    fn test_set() {
+        let mut e1 = Flags::A | Flags::C;
+        e1.set(Flags::B, true);
+        e1.set(Flags::C, false);
+
+        assert_eq!(e1, Flags::A | Flags::B);
+    }
+
+    #[test]
+    fn test_assignment_operators() {
+        let mut m1 = Flags::empty();
+        let e1 = Flags::A | Flags::C;
+        // union
+        m1 |= Flags::A;
+        assert_eq!(m1, Flags::A);
+        // intersection
+        m1 &= e1;
+        assert_eq!(m1, Flags::A);
+        // set difference
+        m1 -= m1;
+        assert_eq!(m1, Flags::empty());
+        // toggle
+        m1 ^= e1;
+        assert_eq!(m1, e1);
+    }
+
+
+    #[cfg(bitflags_const_fn)]
+    #[test]
+    fn test_const_fn() {
+        const _M1: Flags = Flags::empty();
+
+        const M2: Flags = Flags::A;
+        assert_eq!(M2, Flags::A);
+
+        const M3: Flags = Flags::C;
+        assert_eq!(M3, Flags::C);
+    }
+
+    #[test]
+    fn test_extend() {
+        let mut flags;
+
+        flags = Flags::empty();
+        flags.extend([].iter().cloned());
+        assert_eq!(flags, Flags::empty());
+
+        flags = Flags::empty();
+        flags.extend([Flags::A, Flags::B].iter().cloned());
+        assert_eq!(flags, Flags::A | Flags::B);
+
+        flags = Flags::A;
+        flags.extend([Flags::A, Flags::B].iter().cloned());
+        assert_eq!(flags, Flags::A | Flags::B);
+
+        flags = Flags::B;
+        flags.extend([Flags::A, Flags::ABC].iter().cloned());
+        assert_eq!(flags, Flags::ABC);
+    }
+
+    #[test]
+    fn test_from_iterator() {
+        assert_eq!([].iter().cloned().collect::<Flags>(), Flags::empty());
+        assert_eq!(
+            [Flags::A, Flags::B].iter().cloned().collect::<Flags>(),
+            Flags::A | Flags::B
+        );
+        assert_eq!(
+            [Flags::A, Flags::ABC].iter().cloned().collect::<Flags>(),
+            Flags::ABC
+        );
+    }
+
+    #[test]
+    fn test_lt() {
+        let mut a = Flags::empty();
+        let mut b = Flags::empty();
+
+        assert!(!(a < b) && !(b < a));
+        b = Flags::B;
+        assert!(a < b);
+        a = Flags::C;
+        assert!(!(a < b) && b < a);
+        b = Flags::C | Flags::B;
+        assert!(a < b);
+    }
+
+    #[test]
+    fn test_ord() {
+        let mut a = Flags::empty();
+        let mut b = Flags::empty();
+
+        assert!(a <= b && a >= b);
+        a = Flags::A;
+        assert!(a > b && a >= b);
+        assert!(b < a && b <= a);
+        b = Flags::B;
+        assert!(b > a && b >= a);
+        assert!(a < b && a <= b);
+    }
+
+    fn hash<T: Hash>(t: &T) -> u64 {
+        let mut s = DefaultHasher::new();
+        t.hash(&mut s);
+        s.finish()
+    }
+
+    #[test]
+    fn test_hash() {
+        let mut x = Flags::empty();
+        let mut y = Flags::empty();
+        assert_eq!(hash(&x), hash(&y));
+        x = Flags::all();
+        y = Flags::ABC;
+        assert_eq!(hash(&x), hash(&y));
+    }
+
+    #[test]
+    fn test_debug() {
+        assert_eq!(format!("{:?}", Flags::A | Flags::B), "A | B");
+        assert_eq!(format!("{:?}", Flags::empty()), "(empty)");
+        assert_eq!(format!("{:?}", Flags::ABC), "A | B | C | ABC");
+        let extra = unsafe { Flags::from_bits_unchecked(0xb8) };
+        assert_eq!(format!("{:?}", extra), "0xb8");
+        assert_eq!(format!("{:?}", Flags::A | extra), "A | 0xb8");
+        assert_eq!(format!("{:?}", Flags::ABC | extra), "A | B | C | ABC | 0xb8");
+    }
+
+    #[test]
+    fn test_binary() {
+        assert_eq!(format!("{:b}", Flags::ABC), "111");
+        assert_eq!(format!("{:#b}", Flags::ABC), "0b111");
+        let extra = unsafe { Flags::from_bits_unchecked(0b1010000) };
+        assert_eq!(format!("{:b}", Flags::ABC | extra), "1010111");
+        assert_eq!(format!("{:#b}", Flags::ABC | extra), "0b1010111");
+    }
+
+    #[test]
+    fn test_octal() {
+        assert_eq!(format!("{:o}", LongFlags::LONG_A), "177777");
+        assert_eq!(format!("{:#o}", LongFlags::LONG_A), "0o177777");
+        let extra = unsafe { LongFlags::from_bits_unchecked(0o5000000) };
+        assert_eq!(format!("{:o}", LongFlags::LONG_A | extra), "5177777");
+        assert_eq!(format!("{:#o}", LongFlags::LONG_A | extra), "0o5177777");
+    }
+
+    #[test]
+    fn test_lowerhex() {
+        assert_eq!(format!("{:x}", LongFlags::LONG_A), "ffff");
+        assert_eq!(format!("{:#x}", LongFlags::LONG_A), "0xffff");
+        let extra = unsafe { LongFlags::from_bits_unchecked(0xe00000) };
+        assert_eq!(format!("{:x}", LongFlags::LONG_A | extra), "e0ffff");
+        assert_eq!(format!("{:#x}", LongFlags::LONG_A | extra), "0xe0ffff");
+    }
+
+    #[test]
+    fn test_upperhex() {
+        assert_eq!(format!("{:X}", LongFlags::LONG_A), "FFFF");
+        assert_eq!(format!("{:#X}", LongFlags::LONG_A), "0xFFFF");
+        let extra = unsafe { LongFlags::from_bits_unchecked(0xe00000) };
+        assert_eq!(format!("{:X}", LongFlags::LONG_A | extra), "E0FFFF");
+        assert_eq!(format!("{:#X}", LongFlags::LONG_A | extra), "0xE0FFFF");
+    }
+
+    mod submodule {
+        bitflags! {
+            pub struct PublicFlags: i8 {
+                const X = 0;
+            }
+        }
+        bitflags! {
+            struct PrivateFlags: i8 {
+                const Y = 0;
+            }
+        }
+
+        #[test]
+        fn test_private() {
+            let _ = PrivateFlags::Y;
+        }
+    }
+
+    #[test]
+    fn test_public() {
+        let _ = submodule::PublicFlags::X;
+    }
+
+    mod t1 {
+        mod foo {
+            pub type Bar = i32;
+        }
+
+        bitflags! {
+            /// baz
+            struct Flags: foo::Bar {
+                const A = 0b00000001;
+                #[cfg(foo)]
+                const B = 0b00000010;
+                #[cfg(foo)]
+                const C = 0b00000010;
+            }
+        }
+    }
+
+    #[test]
+    fn test_in_function() {
+        bitflags! {
+           struct Flags: u8 {
+                const A = 1;
+                #[cfg(any())] // false
+                const B = 2;
+            }
+        }
+        assert_eq!(Flags::all(), Flags::A);
+        assert_eq!(format!("{:?}", Flags::A), "A");
+    }
+
+    #[test]
+    fn test_deprecated() {
+        bitflags! {
+            pub struct TestFlags: u32 {
+                #[deprecated(note = "Use something else.")]
+                const ONE = 1;
+            }
+        }
+    }
+
+    #[test]
+    fn test_pub_crate() {
+        mod module {
+            bitflags! {
+                pub (crate) struct Test: u8 {
+                    const FOO = 1;
+                }
+            }
+        }
+
+        assert_eq!(module::Test::FOO.bits(), 1);
+    }
+
+    #[test]
+    fn test_pub_in_module() {
+        mod module {
+            mod submodule {
+                bitflags! {
+                    // `pub (in super)` means only the module `module` will
+                    // be able to access this.
+                    pub (in super) struct Test: u8 {
+                        const FOO = 1;
+                    }
+                }
+            }
+
+            mod test {
+                // Note: due to `pub (in super)`,
+                // this cannot be accessed directly by the testing code.
+                pub(super) fn value() -> u8 {
+                    super::submodule::Test::FOO.bits()
+                }
+            }
+
+            pub fn value() -> u8 {
+                test::value()
+            }
+        }
+
+        assert_eq!(module::value(), 1)
+    }
+
+    #[test]
+    fn test_zero_value_flags() {
+        bitflags! {
+            struct Flags: u32 {
+                const NONE = 0b0;
+                const SOME = 0b1;
+            }
+        }
+
+        assert!(Flags::empty().contains(Flags::NONE));
+        assert!(Flags::SOME.contains(Flags::NONE));
+        assert!(Flags::NONE.is_empty());
+
+        assert_eq!(format!("{:?}", Flags::empty()), "NONE");
+        assert_eq!(format!("{:?}", Flags::SOME), "SOME");
+    }
+}