rustup.sh is being confused by dash into 32 bit install on 64 bit linux host

[farcaller]

Specifically,

# Detect 64 bit linux systems with 32 bit userland and force 32 bit compilation
if [ $CFG_OSTYPE = unknown-linux-gnu -a $CFG_CPUTYPE = x86_64 ]
then
    file -L "$SHELL" | grep -q "x86[_-]64"

this check fails with 1, as /bin/sh on default ubuntu 14.04 has an empty $SHELL.

A trivial fix is to use /bin/bash in shebang and update the rustup docs as appropriate.

[brson]

This exact line appears on Rust's configure script, which correctly does a 64-bit build on 64-bit ubuntu. Is there something else going on?

[brson]

rustup.sh correctly installs x86_64 rustc on my install of 14.04

[brson]

Perhaps under normal operation most people are doing this in an interactive (bash) shell, so $SHELL happens to be set.

[farcaller]

Can't reliably reproduce outside of docker's ubuntu:14.04, closing.

[sourcefrog]

I'm hitting something similar, though not quite the same.

Running current rustupup on Debian Jessy from inside of zsh:

+ local _ostype=unknown-linux-gnu
+ local _cputype=x86_64
+ [ unknown-linux-gnu = unknown-linux-gnu -a x86_64 = x86_64 ]
+ local _bin_to_probe=zsh
+ [ -z zsh -a -e /usr/bin/env ]
+ [ -n zsh ]
+ grep -q x86[_-]64
+ file -L zsh
+ [ 1 != 0 ]
+ local _cputype=i686
+ local _arch=i686-unknown-linux-gnu

It seems the problem is $SHELL is just plain zsh with no path, so running file -L $shell fails.