Integer conversions too pedantic in 64-bit

[Walter Bright]

dsimcha wrote:
> Now that DMD has a 64-bit beta available, I'm working on getting a whole bunch
> of code to compile in 64 mode.  Frankly, the compiler is way too freakin'
> pedantic when it comes to implicit conversions (or lack thereof) of
> array.length.  99.999% of the time it's safe to assume an array is not going
> to be over 4 billion elements long.  I'd rather have a bug the 0.001% of the
> time than deal with the pedantic errors the rest of the time, because I think
> it would be less total time and effort invested.  To force me to either put
> casts in my code everywhere or change my entire codebase to use wider integers
> (with ripple effects just about everywhere) strikes me as purity winning out
> over practicality.

We dealt with that in updating Phobos/Druntime to 64 bits. The end result was 
worth it (and yes, there would have been undiscovered bugs without those 
pedantic checks).

Most of the issues are solved if you use auto and foreach where possible, and 
size_t for the rest of the cases.