I followed this tutorial for crosscompiling on Linux https://hackernoon.com/compiling-rust-for-the-raspberry-pi-49fdcd7df658 and it worked.
Now I try to crosscompile from Windows. I use “gnutoolchains com/raspberry/” The linker is in PATH environment variable and runs if I invoke it in cmd, but not if I put it into .cargo/config file like this
[target.armv7-unknown-linux-gnueabihf] linker = "arm-linux-gnueabihf-gcc-4.9"
I have filled an issue for it: https://github.com/rust-lang/cargo/issues/3940