mirror of https://github.com/rust-lang/rust
38 lines
877 B
Rust
38 lines
877 B
Rust
// Check that `ref mut` variables don't change address between the match guard
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// and the arm expression.
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//@ run-pass
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// Test that z always point to the same temporary.
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fn referent_stability() {
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let p;
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match 0 {
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ref mut z if { p = z as *const _; true } => assert_eq!(p, z as *const _),
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_ => unreachable!(),
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};
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}
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// Test that z is always effectively the same variable.
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fn variable_stability() {
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let p;
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match 0 {
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ref mut z if { p = &z as *const _; true } => assert_eq!(p, &z as *const _),
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_ => unreachable!(),
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};
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}
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// Test that a borrow of *z can cross from the guard to the arm.
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fn persist_borrow() {
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let r;
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match 0 {
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ref mut z if { r = z as &_; true } => assert_eq!(*r, 0),
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_ => unreachable!(),
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}
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}
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fn main() {
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referent_stability();
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variable_stability();
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persist_borrow();
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}
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