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* [Bug fortran/65757] New: gfortran gives incorrect result for anint with real*16 argument
@ 2015-04-13 23:33 bugs at dhbailey dot com
  2015-04-14  1:38 ` [Bug libquadmath/65757] " kargl at gcc dot gnu.org
                   ` (10 more replies)
  0 siblings, 11 replies; 12+ messages in thread
From: bugs at dhbailey dot com @ 2015-04-13 23:33 UTC (permalink / raw)
  To: gcc-bugs

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=65757

            Bug ID: 65757
           Summary: gfortran gives incorrect result for anint with real*16
                    argument
           Product: gcc
           Version: 4.9.0
            Status: UNCONFIRMED
          Severity: major
          Priority: P3
         Component: fortran
          Assignee: unassigned at gcc dot gnu.org
          Reporter: bugs at dhbailey dot com

gfortran gives an incorrect result for the anint (nearest whole number)
function for certain real*16 arguments.  Here is a simple example:

program anintbug
implicit none
real (kind (0.q0)) q1, q2, q3

q1 = 233181505644407.99996948242187500000q0
q2 = anint (q1)
q3 = 233181505644408.00000000000000000000q0

write (6, '(f50.25)') q1, q2, q3
write (6, '(z35)') q1, q2, q3
stop
end

When compiled with "gfortran anintbug.f90", this program produces the following
output.  The second result should equal the third result, but does not.

         233181505644407.9999694824218750000000000
         233181505644407.9999694824218750000000000
         233181505644408.0000000000000000000000000
   402EA827999FCEEFFFFC000000000000
   402EA827999FCEEFFFFC000000000000
   402EA827999FCEF00000000000000000


^ permalink raw reply	[flat|nested] 12+ messages in thread

end of thread, other threads:[~2015-04-28 22:09 UTC | newest]

Thread overview: 12+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2015-04-13 23:33 [Bug fortran/65757] New: gfortran gives incorrect result for anint with real*16 argument bugs at dhbailey dot com
2015-04-14  1:38 ` [Bug libquadmath/65757] " kargl at gcc dot gnu.org
2015-04-14 17:26 ` sgk at troutmask dot apl.washington.edu
2015-04-22 23:19 ` bugs at dhbailey dot com
2015-04-23  0:49 ` jvdelisle at gcc dot gnu.org
2015-04-23  0:55 ` sgk at troutmask dot apl.washington.edu
2015-04-23  1:31 ` jvdelisle at gcc dot gnu.org
2015-04-23  8:05 ` dominiq at lps dot ens.fr
2015-04-23 19:54 ` bugs at dhbailey dot com
2015-04-28 17:32 ` joseph at codesourcery dot com
2015-04-28 21:55 ` sgk at troutmask dot apl.washington.edu
2015-04-28 22:09 ` joseph at codesourcery dot com

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