I currently have this problem with the latest bash from Arch linux which is
biting my at(1) commands. Exported functions make the environment
non-parseable.
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robin@bunyip:~
$ export -nf psg hsg #clean out my exported functions
robin@bunyip:~
$ (env;echo echo 'hello') | bash
hello
robin@bunyip:~
$ bilbo(){
> echo 'precious'
> }
robin@bunyip:~
$ export -f bilbo
robin@bunyip:~
$ (env;echo echo 'hello') | bash
bash: line 29: syntax error near unexpected token `='
bash: line 29: `BASH_FUNC_bilbo()=() { echo 'precious''
robin@bunyip:~
$
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latest bash changes can be seen here (various CVE stuff).
https://projects.archlinux.org/svntogit/packages.git/commit/trunk?h=packages/bash&id=66b6f8f71f48b425c53b781c531697988413e503
