------- Comment #114 from pepalogik at seznam dot cz 2008-06-22 16:59 ------- (In reply to comment #113) > It is available when storing a result to memory.
Yes, but this requires quite a complicated workaround (solution (4) in my comment #109). So you could say that the IEEE754 double precision type is available even on a processor without any FPU because this can be emulated using integers. Moreover, if we assess things pedantically, the workaround (4) still doesn't fully obey the IEEE single/double precision type(s), because there remains the problem of double rounding of denormals. > The IEEE754-1985 allows this. Section 4.3: "Normally, a result is rounded to > the precision of its destination. However, some systems deliver results only > to > double or extended destinations. On such a system the user, which may be a > high-level language compiler, shall be able to specify that a result be > rounded > instead to single precision, though it may be stored in the double or extended > format with its wider exponent range. [...]" > [...] > AFAIK, the IEEE754-1985 standard was designed from the x87 > implementation, so it would have been very surprising that x87 didn't conform > to IEEE754-1985. So it seems I was wrong but the IEEE754-1985 standard is also quite "wrong". > > Do you mean that on Windows, long double has (by default) no more precision > > than double? I don't think so (it's confirmed by my experience). > I don't remember my original reference, but here's a new one: > http://msdn.microsoft.com/en-us/library/aa289157(vs.71).aspx > In fact, this depends on the architecture. I quote: "x86. Intermediate > expressions are computed at the default 53-bit precision with an extended > range > [...]" I quote, too: "Applies To Microsoft® Visual C++®" -- http://gcc.gnu.org/bugzilla/show_bug.cgi?id=323 ------- You are receiving this mail because: ------- You are on the CC list for the bug, or are watching someone who is. -- To UNSUBSCRIBE, email to [EMAIL PROTECTED] with a subject of "unsubscribe". Trouble? Contact [EMAIL PROTECTED]
