WRDE_UNDEF
execl(_PATH_BSHELL, "sh", flags & WRDE_UNDEF ? "-u" : "+u",
r = wordexp("${dont_set_me}", &we, WRDE_UNDEF);
r = wordexp("'", &we, WRDE_UNDEF);
r = wordexp("${IFS:+'}", &we, WRDE_UNDEF);
r = wordexp("$(case)", &we, WRDE_UNDEF);
WRDE_SHOWERR + WRDE_UNDEF);