Unable to copy large (>2GB) files using PostgreSQL 11 (Windows)

Hello,

I am unable to use psql's \COPY command to load in large text files on
Windows. Here are the steps I used to reproduce:

1. Install PostgreSQL 11.0 from enterprisedb
2. Create two files: test1.txt (2.4 GB) and test2.txt (1.8 GB) - content
doesn't matter
3. Run SQL Shell (psql)

postgres=# create table tbl (col int);
CREATE TABLE

postgres=# \COPY tbl FROM 'test1.txt'
could not stat file "test1.txt": Unknown error

postgres=# \COPY tbl from 'test2.txt'
(runs normally)

I believe the issue is related to `stat` not handling large files properly.
I installed PostgreSQL 10.5 Windows x86-64 from the EDB website, attempted
to reproduce, and *could not* reproduce the error, so I think this is a
PostgreSQL 11 specific bug.

-Alistair