23 lines
515 B
Rust
23 lines
515 B
Rust
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use std::fmt;
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fn foo() -> Box<impl fmt::Debug+?Sized> {
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let x : Box<[u8]> = Box::new([0]);
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x
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}
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fn bar() -> Box<impl fmt::Debug+?Sized> {
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let y: Box<fmt::Debug> = Box::new([0]);
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y
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}
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fn main() {
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let f = foo();
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let b = bar();
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// this is an `*mut [u8]` in practice
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let f_raw : *mut _ = Box::into_raw(f);
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// this is an `*mut fmt::Debug` in practice
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let mut b_raw = Box::into_raw(b);
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// ... and they should not be mixable
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b_raw = f_raw as *mut _; //~ ERROR is invalid
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}
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