mirror of https://github.com/rust-lang/rust
34 lines
588 B
Rust
34 lines
588 B
Rust
//@ build-pass
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//@ compile-flags: -Z mir-opt-level=4
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#![crate_type = "lib"]
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#![feature(lang_items)]
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#![no_std]
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struct NonNull<T: ?Sized>(*const T);
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struct Unique<T: ?Sized>(NonNull<T>);
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#[lang = "owned_box"]
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pub struct Box<T: ?Sized>(Unique<T>);
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impl<T: ?Sized> Drop for Box<T> {
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#[inline(always)]
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fn drop(&mut self) {
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dealloc(self.0.0.0)
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}
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}
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#[inline(never)]
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fn dealloc<T: ?Sized>(_: *const T) {}
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pub struct Foo<T>(T);
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pub fn foo(a: Option<Box<Foo<usize>>>) -> usize {
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let f = match a {
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None => Foo(0),
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Some(vec) => *vec,
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};
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f.0
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}
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