Changing -O to be equivalent to -O3

[John Colvin]

On Monday, 18 March 2013 at 12:42:10 UTC, David Nadlinger wrote:
> On Monday, 18 March 2013 at 02:25:17 UTC, John Colvin wrote:
>> On Sunday, 17 March 2013 at 18:33:57 UTC, David Nadlinger 
>> wrote:
>>> See: https://github.com/ldc-developers/ldc/pull/315
>>>
>>> Any further opinions?
>>>
>>> David
>>
>> why not O5?
>
> Because -O5 is the same as -O3 right now. I thought this was 
> documented somewhere, but apparently this is not the case. Do 
> you want to fix it? ;)
>
> David

Far from being documented as equivalent to O3, ldc2 --help says 
O4 and O5 are "link-time optimization" Is this also incorrect?