Subject: add '--target=' option for 'guix environment' (similar to 'guix build')

From: Sergei Trofimovich <[email-masked]>
Date: Mon, 1 May 2017 12:35:35 +0100

[ context: https://lists.gnu.org/archive/html/guix-devel/2017-02/msg00966.html ]

Currently 'guix build' supports '--target=' option to allow cross-compilation,
but 'guix environment' doe not. Sometimes it would be nice to peek at the
environment that 'guix build' creates.

Concrete example:

  When debugging 're2' cross-compilation error I used the following command
  to build a package:

    ./pre-inst-env guix build --check re2 --target=alpha-unknown-linux-gnu --no-grafts

  I was not sure what does g++ vs. TARGET-g++ means in guix.

  Would be nice to have an ability to get exactly build environment as:

    ./pre-inst-env guix environment re2 --target=alpha-unknown-linux-gnu --no-grafts

Thanks!

-- 

  Sergei