check_lstrings fails at Windows

[Vincent van Ravesteijn]

The entries that are different from the test_lstrings reference file are 
for the inputs

{
...
1.3754937356458394574047e17,
1.3754937356458394574047e18,
1.3754937356458394574047e19,
1.3754937356458394574047e20,
...
1e42
}
and the outputs are:

{
...
137549373564583950
1375493735645839400
13754937356458394000
137549373564583950000
...
100000000000000010000000000000000
}

The same entries also fail for the negated case.

Vincent