rust crossbuild fails

gistfile1.txt

Working within an xbps-src chroot:

$ xbps-query -p pkgver rust
rust-1.28.0_2

$ xbps-query -p pkgver  -s cross      
cross-aarch64-linux-gnu-0.28_1: cross-aarch64-linux-gnu-0.28_1
cross-aarch64-linux-gnu-libc-0.28_1: cross-aarch64-linux-gnu-libc-0.28_1


following https://github.com/japaric/rust-cross#cross-compiling-with-rustc:

$ cat hello.rs
fn main() {
    println!("Hello, world!");
}

native build is fine:

$ rustc hello.rs && ./hello
Hello, world!

rustc available cross-build targets for aarch64: 

$ rustc --print target-list | grep aarch64
aarch64-linux-android
aarch64-unknown-cloudabi
aarch64-unknown-freebsd
aarch64-unknown-fuchsia
aarch64-unknown-linux-gnu
aarch64-unknown-linux-musl
aarch64-unknown-openbsd

1s crossbuild try:

$ rustc --target=aarch64-unknown-linux-gnu hello.rs
error[E0463]: can't find crate for `std`
  |
  = note: the `aarch64-unknown-linux-gnu` target may not be installed

error: aborting due to previous error

For more information about this error, try `rustc --explain E0463`.


2nd build try:

$ rustc  --target=aarch64-unknown-linux-gnu -C linker=aarch64-linux-gnu-gcc hello.rs
error[E0463]: can't find crate for `std`
  |
  = note: the `aarch64-unknown-linux-gnu` target may not be installed

error: aborting due to previous error

For more information about this error, try `rustc --explain E0463`.

Have to provides the necessary paths that are provided since install rust for crossbuilding too:

$ rustc -L /usr/aarch64-linux-gnu/lib/rustlib/aarch64-unknown-linux-gnu/lib \
		--target=aarch64-unknown-linux-gnu \
		 -C linker=aarch64-linux-gnu-gcc \
		hello.rs

check it's fine:

$ file hello
hello: ELF 64-bit LSB shared object, ARM aarch64, version 1 (SYSV), dynamically linked, interpreter /lib/ld-linux-aarch64.so.1, for GNU/Linux 3.7.0, BuildID[sha1]=e32b29801cce80896e3444beb47310f0235dc6ae, not stripped