Accept any length symbols' strings

[foxtran]

Noticed with xtb/vertical test, where length of symbols' strings equals one

[awvwgk]

This would not work if you don't account for the variable character length in the allocation of the temporary array.

[foxtran]

@awvwgk, why does not it work? character(len=:), allocatable :: str(:) can be also passed into character(len=*), allocatable :: str(:).

See an example here: https://godbolt.org/z/fc7nTKxnP