css/css-flexbox/negative-flex-rounding-crash.html

<!DOCTYPE html>
<title>CSS Flexbox: Crash caused by rounding error in flex-shrink</title>
<link rel="author" title="Tony Chang" href="mailto:tony@chromium.org">
<link rel="help" href="https://drafts.csswg.org/css-flexbox/#resolve-flexible-lengths">
<link rel="issue" href="https://bugs.webkit.org/show_bug.cgi?id=97606">
<meta name="assert" content="Check that crash doesn't happen in flex-shrink due to floating point precision errors.">

<style>
.math {
    display: inline-flex;
}
.math > * {
    padding-bottom: 0.35em;
}
.mfrac {
    display: inline-flex;
    flex-direction: column;
}
.mfrac > :first-child {
    margin-block-end: 0.2em;
}
.mfrac > :last-child {
    margin-block-start: 0.2em;
}
.x {
    line-height: 9px;
}
.y {
    line-height: 12px;
}
</style>
<div class=math>
    <div class=mfrac>
        <div class=mfrac>
            <div class=x>x</div>
            <div class=y>y</div>
        </div>
        <div class=mfrac>
            <div class=mfrac>
                <div class=x>x</div>
                <div class=y>y</div>
            </div>
            <div class=x>z</div>
        </div>
    </div>
</div>