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        <tr>
          <th>Bug ID</th>
          <td><a class="bz_bug_link 
          bz_status_NEW "
   title="NEW - RenderBox::hasDefiniteLogicalHeight() shouldn't consider all abspos elements as definite"
   href="https://bugs.webkit.org/show_bug.cgi?id=159251">159251</a>
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        </tr>

        <tr>
          <th>Summary</th>
          <td>RenderBox::hasDefiniteLogicalHeight() shouldn't consider all abspos elements as definite
          </td>
        </tr>

        <tr>
          <th>Classification</th>
          <td>Unclassified
          </td>
        </tr>

        <tr>
          <th>Product</th>
          <td>WebKit
          </td>
        </tr>

        <tr>
          <th>Version</th>
          <td>WebKit Nightly Build
          </td>
        </tr>

        <tr>
          <th>Hardware</th>
          <td>Unspecified
          </td>
        </tr>

        <tr>
          <th>OS</th>
          <td>Unspecified
          </td>
        </tr>

        <tr>
          <th>Status</th>
          <td>NEW
          </td>
        </tr>

        <tr>
          <th>Severity</th>
          <td>Normal
          </td>
        </tr>

        <tr>
          <th>Priority</th>
          <td>P2
          </td>
        </tr>

        <tr>
          <th>Component</th>
          <td>Layout and Rendering
          </td>
        </tr>

        <tr>
          <th>Assignee</th>
          <td>webkit-unassigned&#64;lists.webkit.org
          </td>
        </tr>

        <tr>
          <th>Reporter</th>
          <td>rego&#64;igalia.com
          </td>
        </tr>

        <tr>
          <th>CC</th>
          <td>jfernandez&#64;igalia.com, rego&#64;igalia.com, simon.fraser&#64;apple.com, svillar&#64;igalia.com
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        <pre>Created <span class=""><a href="attachment.cgi?id=282326" name="attach_282326" title="Test case to reproduce the issue">attachment 282326</a> <a href="attachment.cgi?id=282326&amp;action=edit" title="Test case to reproduce the issue">[details]</a></span>
Test case to reproduce the issue

An abspos element doesn't have a definite height unless it has a specified height or the top and bottom properties are not auto.

For example, the following div doesn't have a definite height:
  &lt;div style=&quot;position: absolute;&quot;&gt;&lt;/div&gt;

However, this one will have a definite height:
  &lt;div style=&quot;position: absolute; top: 0; bottom: 0;&quot;&gt;&lt;/div&gt;

RenderBox::hasDefiniteLogicalHeight() is considering that both have a definite height which is wrong:
<a href="http://trac.webkit.org/browser/trunk/Source/WebCore/rendering/RenderBox.cpp#L4760">http://trac.webkit.org/browser/trunk/Source/WebCore/rendering/RenderBox.cpp#L4760</a>

This leads to wrong results in CSS Grid Layout check the attached example, the 50% in the 2nd row is resolved against the 100px of the first row when it should be considered &quot;auto&quot;.
You can check it live at: <a href="http://jsbin.com/xuyane/1/edit?html,css,output">http://jsbin.com/xuyane/1/edit?html,css,output</a></pre>
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