fix(math): stop the internal abs helper from leaking negative zero - #3937
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Closes moonbitlang#3914 Signed-off-by: 林晨 (Leo Cheng) <leo-cheng@vip.qq.com>
Kaida-Amethyst
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Aug 4, 2026
Kaida-Amethyst
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August 4, 2026 07:05
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For a tiny negative
yand a largex,y / xunderflows to-0.0. The internalabshelper isif x < 0.0 { -x } else { x }, and since-0.0 < 0.0is false it returns-0.0unchanged instead of+0.0. atan2 then doesatan(-0.0) = -0.0and negates it for the quadrant, flipping the result to+0.0when it should stay-0.0.Fixed the helper to defer to the builtin
.abs(), which clears the sign bit. Added a regression test for the underflow case.Closes #3914