Incorrect redirection undoing in subshell
yash -c '(trap "echo foo" EXIT) >/dev/null' should print nothing, but yash 2.50 prints foo.
The test case for this bug is from smoosh's test suite: https://github.com/mgree/smoosh/blob/55bb5bc561191b888bf0e403b7a584c4f7894580/tests/shell/semantics.subshell.redirect.test
Fixed in r4106
yash -c '(trap "echo foo" EXIT) >/dev/null' should print nothing, but yash 2.50 prints foo.