Bug 17538 - incorrect rounding when adding/subtracting decimal values and precision of result is beyond decimal type (28+)
Summary: incorrect rounding when adding/subtracting decimal values and precision of re...
Alias: None
Product: Runtime
Classification: Mono
Component: General ()
Version: 3.2.x
Hardware: PC Windows
: --- normal
Target Milestone: ---
Assignee: Bugzilla
Depends on:
Reported: 2014-01-31 07:12 UTC by INOMATA Kentaro
Modified: 2015-02-06 15:32 UTC (History)
5 users (show)

Is this bug a regression?: ---
Last known good build:

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Description INOMATA Kentaro 2014-01-31 07:12:57 UTC
from http://d.hatena.ne.jp/hnw/20140104

decimal dcm3 = 987654321098765432109876543.2m;
decimal dcm4 = 0.05m;
decimal dcm5 = dcm3 + dcm4;

dcm3 + dcm4 is 987654321098765432109876543.25 and it IS equally close to two representable values, so "bankers' rounding" is expected, but actual value is 987654321098765432109876543.3.
Comment 1 Zoltan Varga 2014-02-01 22:08:50 UTC
->class libs for now
Comment 2 Marek Safar 2014-02-03 03:15:50 UTC
Addition/subtraction code is implemented in runtime
Comment 3 Miguel de Icaza [MSFT] 2015-02-06 15:32:59 UTC
Fixed with the new Decimal code.