Here's a challenge for floating point lovers.
Doug Gwyn
gwyn at smoke.brl.mil
Thu Jan 24 09:36:10 AEST 1991
In article <1991Jan22.180927.29232 at zoo.toronto.edu> henry at zoo.toronto.edu (Henry Spencer) writes:
>>Does ANSI X3.159 require the ability to define such a constant?
>No. Nobody's come up with a good way of doing this that I know of,
>especially when portability is desired.
Presumably portability is not an issue for this application. What some
implementors do is to initialize what amounts to a union type with the
proper bits then refer to the floating-point member of that union to get
the value interpreted properly with the proper floating type. The
standard does NOT require that the values of the <float.h> macros be
CONSTANT expressions; in particular they may access external storage at
run time (contents of such a union, for example). Note also that this
means that FLT_RADIX and other <float.h> macros must not be used in #if
expressions in strictly conforming programs.
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