Re: Conflicts between C standard and 754-2008
On Jan 25 2011, Vincent Lefevre wrote:
I'm not talking about the evaluation, but about the expression
definition. The parsing defines the expression in term of operations.
The evaluation of an expression is another matter.
Precisely. And the question is whether the "as if" rule allows the
evaluation to use a mathematically equivalent form - even if that is
not equivalent in IEEE 754. Both C90 and C99 are seriously ambiguous,
in somewhat different ways.
It seems that every one except you understands what the C standard
means on this point...
Perhaps that's because I was involved in WG14 during the standardisation
of both C90 and C99, and remember the debates on this very topic?
Anyway, enough is enough.
Regards,
Nick Maclaren.