[Bug libfortran/38199] [4.7/4.8 Regression] missed optimization: I/O performance

[tkoenig at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=38199

--- Comment #24 from Thomas Koenig <tkoenig at gcc dot gnu.org> 2013-02-17 11:25:15 UTC ---

> Based on those timings, it is a regression - hence, I marked it as such.

Non-trivial to fix. To implement array I/O, we would have to call
len_trim on every record at the right place, then update it.

I am tempted to put something original_recl into gfc_unit and set
recl to the length of the current record for internal array I/O
in next_record_r.

I'll play arond a bit with this idea, but it is probably more 4.9
material.