Rand on OSX #1388

Rand comportement is different between OS X and Linux distribution (Debian).
For this code:

print(1000.rand)

Result on OS X is:

$ ./rand 
801

$ ./rand 
801

$ ./rand 
801

$ ./rand 
801

Result on Debian is:

$ ./rand 
536

$ ./rand 
256

$ ./rand 
612

$ ./rand 
828

This tests is realized with:
Debian 8
OS X: 10.10.4 (Yosemite)

Ping @ablondin