On 2010-02-22 02:58:19 +0000, Joseph S. Myers wrote: > For example, N1421 (Markham minutes) has a discussion that's clearly > presuming that a conditional > > #if defined(__STDC_IEC_559__) && (FLT_EVAL_METHOD == 1) > > may hold.
Well, this is a bit unclear. I think this is OK, as long as rounding of a float operation is done to single precision (the exponent range may still be the one of the double format, in which case the value of FLT_EVAL_METHOD should be 1 as above). IEEE 754-1985 says: 4.3. Rounding Precision 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. [...] -- Vincent Lefèvre <vinc...@vinc17.net> - Web: <http://www.vinc17.net/> 100% accessible validated (X)HTML - Blog: <http://www.vinc17.net/blog/> Work: CR INRIA - computer arithmetic / Arénaire project (LIP, ENS-Lyon)
