[mystikal]

In theory you could tell the compiler to identify and statically link only those functions needed to make printf work (or a conservative approximation thereof).

[microtonal]

As far as I know, jemalloc is a substantial part of that binary size. See e.g.:

https://github.com/japaric/rust-on-openwrt/issues/1#issuecom...

https://github.com/japaric/std-with-cargo#making-rust-binari...

[Manishearth]

Yeah, that's just running LTO (`-C lto`). This brings the binary size down a bit, thought you also need to opt out of jemalloc to get a good impact.