title: What is the difference between 'asm', '__asm' and '__asm__'?
body: <p>As far as I can tell, the only difference between <code>__asm { ... };</code> and <code>__asm__("...");</code> is that the first uses <code>mov eax, var</code> and the second uses <code>movl %0, %%eax</code> with <code>:"=r" (var)</code> at the end. What other differences are there? And what about just <code>asm</code>?</p>