mirror of https://github.com/rust-lang/rust
25 lines
554 B
Rust
25 lines
554 B
Rust
// General test of maybe_uninits state computed by MIR dataflow.
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#![feature(core_intrinsics, rustc_attrs)]
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use std::intrinsics::rustc_peek;
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use std::mem::{drop, replace};
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struct S(i32);
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#[rustc_mir(rustc_peek_maybe_uninit,stop_after_dataflow)]
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fn foo(x: &mut S) {
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// `x` is initialized here, so maybe-uninit bit is 0.
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rustc_peek(&x); //~ ERROR rustc_peek: bit not set
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::std::mem::drop(x);
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// `x` definitely uninitialized here, so maybe-uninit bit is 1.
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rustc_peek(&x);
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}
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fn main() {
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foo(&mut S(13));
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foo(&mut S(13));
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}
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