The condition this refers to was moved in commit
4efe39d21.
/* shared is only null if we have gone beyond the outermost
lexing scope. In a file, we will have broken out of the
loop in the previous iteration. In an eval, the string buf-
- fer ends with "\n;", so the while condition below will have
+ fer ends with "\n;", so the while condition above will have
evaluated to false. So shared can never be null. */
assert(shared);
/* A LEXSHARED struct with a null ls_prev pointer is the outer-