Re: choice of fixed point type

[tmoran@bix.com]

>(I thought GNAT 3.12p compiled, without warning, the example
>even when "type Duration is delta ..." was replaced with
>"type T is delta ...".  I don't have access to 3.12p right
>now, so I can't verify that.)
  Using "type D is delta ..." also fails to generate any warning.

>> The code in question is really non-portable at best, wrong
>> at worst, but not illegal if there is only one fixed-point
>> type visible. At least that's my reading.
  The code in question arose from testing around an "Ada
surprise".  An execution error had been traced to where a
programmer had written something like
  Long_Float(N * Ada.Numerics.pi)   instead of
  Long_Float(N) * Ada.Numerics.pi
resulting in the use of (relatively imprecise) type Duration
for the multiply instead of Long_Float.  Standard.Duration
was of course (silently) visible, and there was no other
fixed point type in this code, so the compiler did what the
programmer said, but not what he wanted.