*mut T documentation disappeared

[jethrogb]

See https://doc.rust-lang.org/1.12.1/std/primitive.pointer.html vs https://doc.rust-lang.org/1.13.0/std/primitive.pointer.html

Tags: A-documentation or A-rustdoc and regression-from-stable-to-stable

[bluss]

But the doc is present in nightly: https://doc.rust-lang.org/nightly/std/primitive.pointer.html

[ollie27]

This was fixed by #36966.

[jethrogb]

Can you add a test?