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Re: Conflicts between C standard and 754-2008



On 2011-01-01 08:33:16 -0800, Fred J. Tydeman wrote:
On Sat, 01 Jan 2011 10:30:45 -0500 Michel Hack wrote:

So an up-to-date quote of the relevant piece of the standard would be
sufficient to clear the way for a conforming implementation -- good news.

C99 + TC1 + TC2 + TC3 (the most current version of the C Standard)
can be found at:
  http://www.open-std.org/jtc1/sc22/wg14/www/docs/n1256.pdf

C1X (currently being voted on) can be found at:
  http://www.open-std.org/jtc1/sc22/wg14/www/docs/n1539.pdf

OK, there was a change between N1494 and N1539:

N1494 (June 25, 2010):
  If the correct value overïows (7.12.1), plus or minus HUGE_VAL,
  HUGE_VALF, or HUGE_VALL is returned [...]

N1539 (November 16, 2010):
  If the correct value overïows and default rounding is in effect
  (7.12.1), plus or minus HUGE_VAL, HUGE_VALF, or HUGE_VALL is
  returned [...]

So, the current C standard (with TC3) is buggy on this point, but
this will be fixed in the next standard.

-- 
Vincent LefÃvre <vincent@xxxxxxxxxx> - Web: <http://www.vinc17.net/>
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