https://svn.boost.org/trac10/ticket/9675 <p> Between Qt 5.1 and 5.2, the command line syntax for <code>moc</code> changed, breaking builds. Specifically, the <code>-f</code> command line argument works differently: previously, it was <code>-f&lt;file&gt;</code> where <code>&lt;file&gt;</code> could be omitted; in Qt 5.2, it's <code>-f &lt;file&gt;</code> – notice the additional space, and <code>&lt;file&gt;</code> is not optional any more. The moc invocation by the Qt5 module relied on the old behaviour as it passed <code>-f</code> without a filename. Furthermore, the moc input file was passed right after the <code>-f</code> argument. The same usage is now interpreted as the input file being the parameter to <code>-f</code>, and the input it expected on <code>stdin</code>. Since nothing is ever written into it, moc never finishes. </p> en-us /htdocs/site/boost.png https://svn.boost.org/trac10/ticket/9675 Trac 1.4.3