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    <p><code>const void</code> is allowed simply because there is no point making the compiler kick out this one exception to a general rule and it does no harm to leave it in.</p> <p>There is some discussion above that <code>const void*</code> is not very useful:</p> <blockquote> <p>How useful is const void *? I can see how void * const could be, but not the former. –Spidey</p> </blockquote> <p>In fact <code>const void*</code> is sometimes essential. It declares that the thing being pointed to is read only as opposed to <code>void* const</code> which only declares that the pointer itself is constant but not the thing it points to.</p> <p>From my experience, the pointer to constant using <code>const void*</code> is the more useful of the two forms. Of course, there is also <code>const void* const</code> meaning that both the pointer and the thing it points to are constant.</p> <p><code>void*</code> is normally used as a way to pass non-specific pointers around (e.g. with <code>memcpy()</code>). If you want to pass a <code>const char*</code> to such a function then you cannot use <code>void*</code> or you lose the fact that the thing it points to is constant and cannot be altered. Current C++ compilers will refuse to compile that as it would have to implicitly cast the <code>const</code> away, and rightfully so as this data might be in read-only memory and possibly cause an exception if anything tries to write to it.</p> <p>This is why the second argument to <code>memcpy()</code> is <code>const void*</code> and not simply <code>void*</code>.</p>
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    1. POWhat's the point of const void?
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    1. USSie Raybould
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