Thanks for the pull request, and welcome! The Rust team is excited to review your changes, and you should hear from @Jarcho (or someone else) some time within the next two weeks.

Please see the contribution instructions for more information. Namely, in order to ensure the minimum review times lag, PR authors and assigned reviewers should ensure that the review label (S-waiting-on-review and S-waiting-on-author) stays updated, invoking these commands when appropriate:

• @rustbot author: the review is finished, PR author should check the comments and take action accordingly
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Or maybe we should just make a lint for as *const/*mut _, like for as _?

Should this lint be enabled by default like as_underscore? This would break some tests:

FAILURES:
    tests/ui/as_ptr_cast_mut.rs
    tests/ui/borrow_deref_ref.rs
    tests/ui/cast_slice_different_sizes.rs
    tests/ui/manual_c_str_literals.rs
    tests/ui/or_fun_call.rs
    tests/ui/ptr_eq.rs
    tests/ui/ptr_eq_no_std.rs
    tests/ui/ptr_as_ptr.rs
    tests/ui/ref_as_ptr.rs
    tests/ui/transmute_null_to_fn.rs
    tests/ui/transmuting_null.rs
    tests/ui/unnecessary_cast.rs
    tests/ui/zero_ptr_no_std.rs
    tests/ui/zero_ptr.rs
    tests/ui/author/issue_3849.rs

Ping @Soveu. If you can just remove the fixme's in the test this can be merged.

@Jarcho lets do it