32 lines
1.2 KiB
Rust
32 lines
1.2 KiB
Rust
// Copyright 2017 The Rust Project Developers. See the COPYRIGHT
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// file at the top-level directory of this distribution and at
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// http://rust-lang.org/COPYRIGHT.
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//
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// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
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// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
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// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
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// option. This file may not be copied, modified, or distributed
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// except according to those terms.
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#![feature(rustc_attrs)]
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struct MyStruct;
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impl MyStruct {
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#[must_use] //~ WARN `#[must_use]` on methods is experimental
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fn need_to_use_method() -> bool { true }
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}
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#[must_use] //~ WARN `#[must_use]` on functions is experimental
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fn need_to_use_it() -> bool { true }
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// Feature gates are tidy-required to have a specially named (or
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// comment-annotated) compile-fail test (which MUST fail), but for
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// backwards-compatibility reasons, we want `#[must_use]` on functions to be
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// compilable even if the `fn_must_use` feature is absent, thus necessitating
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// the usage of `#[rustc_error]` here, pragmatically if awkwardly solving this
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// dilemma until a superior solution can be devised.
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#[rustc_error]
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fn main() {} //~ ERROR compilation successful
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