28f87e4141
Fixes sandboxed build of glibc. Discussion about a similar failure on aarch64 at:
https://github.com/NixOS/nixpkgs/commit/8bfa9f528c88243578246798c7c2ddde045e0de0.
Picked from the following cross-trunk evaluation:
http://hydra.nixos.org/eval/1349278 based on nixpkgs
commit 1f32d4b4eb.
armv5tel job: http://hydra.nixos.org/build/51569718
armv6l job: http://hydra.nixos.org/build/51569717
armv7l job: http://hydra.nixos.org/build/51569713