https://svn.boost.org/trac10/ticket/4617 <p> Not 100% sure it is a bug, but use of additional string streams seems a bit odd. </p> <pre class="wiki"> template&lt;class E, class T, class ME&gt; // BOOST_UBLAS_INLINE This function seems to be big. So we do not let the compiler inline it. std::basic_ostream&lt;E, T&gt; &amp;operator &lt;&lt; (std::basic_ostream&lt;E, T&gt; &amp;os, const matrix_expression&lt;ME&gt; &amp;m) { typedef typename ME::size_type size_type; size_type size1 = m ().size1 (); size_type size2 = m ().size2 (); std::basic_ostringstream&lt;E, T, std::allocator&lt;E&gt; &gt; s; s.flags (os.flags ()); s.imbue (os.getloc ()); s.precision (os.precision ()); s &lt;&lt; '[' &lt;&lt; size1 &lt;&lt; ',' &lt;&lt; size2 &lt;&lt; "]("; if (size1 &gt; 0) { s &lt;&lt; '(' ; if (size2 &gt; 0) s &lt;&lt; m () (0, 0); for (size_type j = 1; j &lt; size2; ++ j) s &lt;&lt; ',' &lt;&lt; m () (0, j); s &lt;&lt; ')'; } for (size_type i = 1; i &lt; size1; ++ i) { s &lt;&lt; ",(" ; if (size2 &gt; 0) s &lt;&lt; m () (i, 0); for (size_type j = 1; j &lt; size2; ++ j) s &lt;&lt; ',' &lt;&lt; m () (i, j); s &lt;&lt; ')'; } s &lt;&lt; ')'; return os &lt;&lt; s.str ().c_str (); } </pre><p> why do we create stringstream 's' and serialize everything in memory and only then pump it to 'os'? </p> en-us /htdocs/site/boost.png https://svn.boost.org/trac10/ticket/4617 Trac 1.4.3 Steven Watanabe Wed, 01 Sep 2010 14:33:46 GMT