@@ -15,20 +15,24 @@ boggling.
1515 is going to cause arbitrary chaos that can't really be predicted. Do not
1616 transmute ` 3 ` to ` bool ` . Even if you never * do* anything with the ` bool ` . Just
1717 don't.
18+
1819* Transmute has an overloaded return type. If you do not specify the return type
1920 it may produce a surprising type to satisfy inference.
20- * Transmuting an & to &mut is UB.
21- * Transmuting an & to &mut is * always* UB.
21+
22+ * Transmuting an ` & ` to ` &mut ` is UB.
23+ * Transmuting an ` & ` to ` &mut ` is * always* UB.
2224 * No you can't do it.
2325 * No you're not special.
26+
2427* Transmuting to a reference without an explicitly provided lifetime
25- produces an [ unbounded lifetime]
28+ produces an [ unbounded lifetime] .
29+
2630* When transmuting between different compound types, you have to make sure they
2731 are laid out the same way! If layouts differ, the wrong fields are going to
2832 get filled with the wrong data, which will make you unhappy and can also be UB
2933 (see above).
3034
31- So how do you know if the layouts are the same? For ` repr(C) ` types and
35+ So how do you know if the layouts are the same? For ` repr(C) ` types and
3236 ` repr(transparent) ` types, layout is precisely defined. But for your
3337 run-of-the-mill ` repr(Rust) ` , it is not. Even different instances of the same
3438 generic type can have wildly different layout. ` Vec<i32> ` and ` Vec<u32> `
@@ -47,7 +51,7 @@ pointer casts or `union`s, but without any of the lints or other basic sanity
4751checks. Raw pointer casts and ` union ` s do not magically avoid the above rules.
4852
4953
50- [ unbounded lifetime ] : unbounded-lifetimes.html
54+ [ unbounded lifetime ] : ./ unbounded-lifetimes.md
5155[ transmute ] : ../std/mem/fn.transmute.html
5256[ transmute_copy ] : ../std/mem/fn.transmute_copy.html
5357[ ucg-layout ] : https://rust-lang.github.io/unsafe-code-guidelines/layout.html
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