All perlbrew seems to do is create a symbolic link to Perl. Sounds like a red herring.

Then you've shown that Perl does output foo. The difference appears to be whether STDOUT is connected to a terminal or not. Odd.

Are you sure you didn't see it because foo appears after the fark at line? No newline caused STDOUT to be flushed before perl exits.

$ perl -e'print "foo"; die "fark"'
fark at -e line 1.
foo
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