On Mon, Nov 30, 2015 at 06:25:15PM +0100, Michael Niedermayer wrote:
> On Mon, Nov 30, 2015 at 04:52:20PM +0100, Nicolas George wrote:
> > Le decadi 10 frimaire, an CCXXIV, Muhammad Faiz a écrit :
> > > - if (s->basefreq != BASEFREQ || s->endfreq != ENDFREQ) {
> > > + if (s->basefreq != (double) BASEFREQ || s->endfreq != (double)
> > > ENDFREQ) {
> >
> > Looks wrong to me. Since s->basefreq is double and operands are always
> > converted to the largest type before comparison, the cast would be implicit.
> > And BASEFREQ and ENDFREQ are double anyway.
> >
> > The problem, if any, is somewhere else.
>
> ISO/IEC 9899:TC3
> 5.2.4.2.2 Characteristics of floating types <float.h>
>
> 8 Except for assignment and cast (which remove all extra range and
> precision), the values
> of operations with floating operands and values subject to the usual
> arithmetic
> conversions and of floating constants are evaluated to a format whose
> range and precision
> may be greater than required by the type. The use of evaluation formats
> is characterized
> by the implementation-defined value of FLT_EVAL_METHOD:19)
> -1 indeterminable;
> 0 evaluate all operations and constants just to the range and
> precision of the
> type;
> 1 evaluate operations and constants of type float and double to
> the
> range and precision of the double type, evaluate long double
> operations and constants to the range and precision of the
> long double
> type;
> 2 evaluate all operations and constants to the range and
> precision of the
> long double type.
> All other negative values for FLT_EVAL_METHOD characterize
> implementation-defined
> behavior.
a few more related parts:
5 The accuracy of the floating-point operations (+, -, *, /) and of the
library functions in
<math.h> and <complex.h> that return floating-point results is
implementation-
defined, as is the accuracy of the conversion between floating-point
internal
representations and string representations performed by the library
functions in
<stdio.h>, <stdlib.h>, and <wchar.h>. The implementation may state that the
accuracy is unknown.
6.4.4.2 Floating constants
7 The translation-time conversion of floating constants should match the
execution-time
conversion of character strings by library functions, such as strtod, given
matching
inputs suitable for both conversions, the same result format, and default
execution-time
rounding.64)
>
>
> [...]
>
> --
> Michael GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB
>
> Republics decline into democracies and democracies degenerate into
> despotisms. -- Aristotle
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Michael GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB
Freedom in capitalist society always remains about the same as it was in
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