cross-compiling in core-updates

[rennes]

When I try './pre-inst-env guix build --target=i586-pc-gnu  
bootstrap-tarballs' in core-updates, get the error:

@ build-started  
/gnu/store/ya79b5bk7b819nh64k3lk5iwjmg5hnan-bash-static-4.4.12.drv -  
x86_64-linux  
/var/log/guix/drvs/ya//79b5bk7b819nh64k3lk5iwjmg5hnan-bash-static-4.4.12.drv.bz2
ice-9/psyntax.scm:1534:32: In procedure expand-macro:
ice-9/psyntax.scm:1534:32: Syntax error:
/gnu/store/9drn9v3pkgwxys8wkmv0pkiqaqv5dqyg-bash-static-4.4.12-guile-builder:1:2300:  
source expression failed to match any pattern in form (%modify-phases  
phases* (delete (quote move-development-files)))
builder for  
`/gnu/store/ya79b5bk7b819nh64k3lk5iwjmg5hnan-bash-static-4.4.12.drv'  
failed with exit code 1
@ build-failed  
/gnu/store/ya79b5bk7b819nh64k3lk5iwjmg5hnan-bash-static-4.4.12.drv - 1  
builder for  
`/gnu/store/ya79b5bk7b819nh64k3lk5iwjmg5hnan-bash-static-4.4.12.drv'  
failed with exit code 1

I'm trying to find the cause!