2015-09-09 20:04:55 +00:00
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use std::mem;
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fn leak<T>(mut b: Box<T>) -> &'static mut T {
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// isn't this supposed to be safe?
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let inner = &mut *b as *mut _;
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mem::forget(b);
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unsafe { &mut *inner }
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}
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fn evil(mut s: &'static mut String)
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{
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// create alias
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let alias: &'static mut String = s;
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let inner: &str = &alias;
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// free value
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2015-10-06 20:45:56 +00:00
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*s = String::new(); //~ ERROR cannot assign
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2015-09-09 20:04:55 +00:00
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let _spray = "0wned".to_owned();
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// ... and then use it
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println!("{}", inner);
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}
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fn main() {
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evil(leak(Box::new("hello".to_owned())));
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}
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