280544 - Javascript multiplication of float values produces incorrect result

Status: VERIFIED DUPLICATE of bug 5856

(Core :: JavaScript Engine, defect)

Description

[Jonathan Lozinski]

User-Agent:       Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.7.5) Gecko/20050128 Firefox/1.0 (Ubuntu) (Ubuntu package 1.0+dfsg.1-2ubuntu5)
Build Identifier: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.7.5) Gecko/20050128 Firefox/1.0 (Ubuntu) (Ubuntu package 1.0+dfsg.1-2ubuntu5)

When multiplying the float value 2.3 by 100 the values are incorrect.
example 2.3 * 100 is not 230, but 229.99999999997:



Reproducible: Always

Steps to Reproduce:
alert(2.3*100) => result expected 230, actual 229.99999999997
alert(2.33*100) => result expected 233, actual 233
alert(2.29*100) => result expected 229, actual 229.99999999997
Actual Results:  
values are not always correct

Expected Results:  
values are correct always

does not appear to be true for epiphany, (Mozilla/5.0 (X11; U; Linux i686;
en-US; rv:1.7.5) Gecko/20050128 Epiphany/1.5.5 (Ubuntu) (Ubuntu package
1.0+dfsg.1-2ubuntu5))

Comment 1

[Bob Clary [:bc] (inactive)]

prolly invalid. See
<http://groups-beta.google.com/group/netscape.public.mozilla.jseng/browse_frm/thread/4b534c1f4cb952dc/6917c3ec8143cf7>.

Comment 2

[Brendan Eich [:brendan]]

This is a dup of bug 190303, which is itself probably an unmarked dup of a much
older bug.

/be

*** This bug has been marked as a duplicate of 190303 ***

Comment 3

[Brendan Eich [:brendan]]

The older bug is bug 5856, so anyone feeling strongly about it, feel free to
reopen and redup this bug and bug 190303.

/be