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copied!<p>I would assume that your version of GCC trips over the fact that <code>TestClass().str</code> is an <em>rvalue</em> array (quite an exotic thing in both C and C++ languages). Something in the specifics of reference initialization when the initailizer is an <em>rvalue</em> is implemented incorrectly. Apparently, the bug was fixed in later versions.</p> <p>Meanwhile both <code>obj.str</code> and <code>TestClass().getStr()</code> are <em>lvalue</em> arrays. They are handled by the straightforward rules of direct reference binding, so the issue does not arise.</p> <p><em>To address the comment:</em> </p> <p>If you modify your function template to </p> <pre><code>template <typename T> printFunc(const T str) </code></pre> <p>the situation will change drastically. Now it is no longer a reference-binding issue. Now the array-to-pointer conversion rules take over. </p> <p>In your original version the type <code>T</code> was deduced as <code>char [6]</code>, while in this new one it is deduced as <code>char *</code>. Your array type is completely lost when the argument is passed to the function: it's a pointer that gets passed instead. This completely eliminates the original issue of reference binding and makes the code compile regardless of the lvalue-ness or rvalue-ness of the array.</p> <p>For example, you can try printing <code>sizeof str</code> inside your function and observe the difference between the two versions. The original will print your array size in bytes (<code>6</code>), while the new one will print pointer size (<code>4</code> for ideone's platform).</p>

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