The line 76 is in C:/WindRiver/workspace/WPILib/Resource.cpp not in your code.
That line is checking to see if the index has already been allocated.
Code:
if ( m_isAllocated[index] )
{
wpi_fatal(ResourceAlreadyAllocated);
return 0;
}
Looking further up to see where it is used, Relay uses is it in InitRelay. So this tells me that you have two relay objects that are set up on the same slot.
Check where you declare your variables. You'll get that error if you're trying to create two relays on the same slot. Make sure you don't have something like:
Relay r1(1);
Relay r2(1);