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* floating point decimal to binary conversion errors
@ 2002-10-03 14:55 Stephen L Moshier
  2002-10-03 17:50 ` Richard Henderson
  0 siblings, 1 reply; 2+ messages in thread
From: Stephen L Moshier @ 2002-10-03 14:55 UTC (permalink / raw)
  To: gcc


The method that gcc uses to convert decimal strings to floating point
binary numbers has been changed.  A cursory test shows differences
that did not occur before.  gcc previously had high enough accuracy
to get powers of ten correct.

Compiled value of 1.0e-4667
036f79d3 a800edaa ca757023 547080fa  (quad precision, sparc)
should be
036f79d3 a800edaa ca757023 547080f9

Compiled value of 1.0e3426
6c73e648 82f8b0f7 3d9f3d45 c00ced47
should be
6c73e648 82f8b0f7 3d9f3d45 c00ced48

Compiled value of 1.0e3952
73473284 c586d770 4095c912 924c3ab8
should be
73473284 c586d770 4095c912 924c3ab9

^ permalink raw reply	[flat|nested] 2+ messages in thread

* Re: floating point decimal to binary conversion errors
  2002-10-03 14:55 floating point decimal to binary conversion errors Stephen L Moshier
@ 2002-10-03 17:50 ` Richard Henderson
  0 siblings, 0 replies; 2+ messages in thread
From: Richard Henderson @ 2002-10-03 17:50 UTC (permalink / raw)
  To: Stephen L Moshier; +Cc: gcc

On Thu, Oct 03, 2002 at 04:49:45PM -0400, Stephen L Moshier wrote:
> The method that gcc uses to convert decimal strings to floating point
> binary numbers has been changed.  A cursory test shows differences
> that did not occur before.  gcc previously had high enough accuracy
> to get powers of ten correct.

Confirmed.  I'll look into it.


r~

^ permalink raw reply	[flat|nested] 2+ messages in thread

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