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+An incompatible cast was attempted.
+
+Erroneous code example:
+
+```compile_fail,E0606
+let x = &0u8; // Here, `x` is a `&u8`.
+let y: u32 = x as u32; // error: casting `&u8` as `u32` is invalid
+```
+
+When casting, keep in mind that only primitive types can be cast into each
+other. Example:
+
+```
+let x = &0u8;
+let y: u32 = *x as u32; // We dereference it first and then cast it.
+```
+
+For more information about casts, take a look at the Type cast section in
+[The Reference Book][1].
+
+[1]: https://doc.rust-lang.org/reference/expressions/operator-expr.html#type-cast-expressions