Cross compiling from windows to linux-musl

[Diggsey]

It works! Almost.

rustc passes an additional library to the linker -lutils, which doesn't exist in the musl std package, and doesn't seem to be required. With that library removed, cross compiling to linux works out of the box with rustup (assuming you can obtain an elf linker...).

[sanmai-NL]

Do you propose to remove that linker option? May seem obvious, but you didn't state that.

[Diggsey]

Well I was hoping that someone could tell me whether utils is required for musl builds, or if its presence in the linker flags is a mistake.

Having looked into it, it seems to be the case that libutils for musl is just an empty library, but is still required in case we're linking with C code which expects to be able to link to it, so probably we should be including libutils as part of the rust package.

[alexcrichton]

Added in rust-lang/libc#246 by accident I fixed in rust-lang/libc#287 but we unfortunately can't update until rust-lang/libc#291 lands (but hopefully that'll be soon!)