21 lines
452 B
Rust
21 lines
452 B
Rust
static mut PTR: *mut u8 = 0 as *mut _;
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fn fun1(x: &mut u8) {
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unsafe {
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PTR = x;
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}
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}
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fn fun2() {
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// Now we use a pointer we are not allowed to use
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let _x = unsafe { *PTR }; //~ ERROR does not exist on the stack
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}
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fn main() {
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let mut val = 0;
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let val = &mut val;
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fun1(val);
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*val = 2; // this invalidates any raw ptrs `fun1` might have created.
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fun2(); // if they now use a raw ptr they break our reference
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}
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