bug#25775: Can't install packages after guix pull

[Pjotr Prins]

I am seeing the same on a fresh checkout and build:

penguin2:~/genenetwork/guix$ ./pre-inst-env guix package -p 
$HOME/opt/guix-build-system --install autoconf
warning: failed to install locale: Invalid argument
Backtrace:
In guix/packages.scm:
 982: 19 [bag-grafts # #]
 966: 18 [fold-bag-dependencies #<procedure 3cc5a20 at guix/packages.scm:982:29 
(package grafts)> ...]
 983: 17 [#<procedure 3cc5a20 at guix/packages.scm:982:29 (package grafts)> # 
()]
 786: 16 [cache! #<weak-key-hash-table 190de00 0/223> # "x86_64-linux" ...]
 910: 15 [thunk]
 786: 14 [cache! #<weak-key-hash-table 18fc520 167/223> # # ...]
1092: 13 [thunk]
1024: 12 [bag->derivation # # #]
In srfi/srfi-1.scm:
 578: 11 [map #<procedure 43a1960 at guix/packages.scm:1026:30 (t-1699962)> #]
In guix/packages.scm:
 846: 10 [expand-input # # # ...]
In guix/store.scm:
1249: 9 [run-with-store # ...]
In guix/packages.scm:
 480: 8 [#<procedure 43f9f60 at guix/packages.scm:480:2 (state)> #]
 485: 7 [#<procedure 3f5ff40 at guix/packages.scm:485:34 (state)> #]
In gnu/packages/bash.scm:
 249: 6 [#<procedure 3f5ff80 at gnu/packages/bash.scm:249:2 (state)> #]
In guix/download.scm:
 421: 5 [#<procedure 418ea00 at guix/download.scm:421:2 (state)> #]
In guix/store.scm:
1169: 4 [#<procedure 43f9e10 at guix/store.scm:1168:28 (store)> #]
In guix/packages.scm:
 786: 3 [cache! #<weak-key-hash-table 18fc520 167/223> #f ...]
1092: 2 [thunk]
 786: 1 [cache! #<weak-key-hash-table 1900640 169/223> #f ...]
 871: 0 [thunk]

@ commit 42e721a13d6f47397e585f5909d140c4bafb4ad0

Installation with --no-grafts passes fine.

Pj.