o Double-precision floating-point numbers are always rounded.
o The alternate form of .D_FLOATING is .DOUBLE.
o You can only use this directive within data or mixed psects
(psects that have either the NOEXE or MIX attributes).
o If automatic data alignment is enabled, this directive aligns
the current location counter to a quadword (64-bit) boundary
before allocating storage.
o The Alpha architecture supports only conversion operations
for the
D floating-point data type.