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copied!<p>Your problem is most probably pointer arithmetic.</p> <p><code>ino_table + i * sizeof(struct inode)</code></p> <p>is most probably not what you want, but </p> <p><code>ino_table + i</code></p> <p>as due to pointer arithmetic <code>ino_table + i</code> is already doing </p> <p><code>((char *)ino_table) + i * sizeof(struct inode)</code></p> <p>The same applies to gdb, where <code>ino_table + 8000</code> refers to <code>&ino_table[8000]</code>- the 8000th element of <code>ino_table</code>, which, unless your struct inode is defined to be 1 byte in size, would be outside of the allocated memory.</p> <hr> <p><strong>More genericly speaking:</strong></p> <p><em><strong>If you have a pointer P to a type T, then P++ will increment the address stored in P by sizeof(T), and NOT by one byte.</em></strong></p> <hr> <p>Also, instead of</p> <p><code>ino_table + i</code></p> <p>you could do</p> <p><code>&ino_table[i]</code></p> <p>which is preferred by many people (I personally don't really care) because it makes it more obvious that increasing <code>i</code> increases the accessed address by <strong>one element, and <em>not</em> one byte</strong>.</p> <hr> <p>And for the malloc you could do</p> <p><code>malloc(number_of_elements * sizeof(type))</code> - don't worry about performance difference or code size, as when number_of_elements is constant, the expression should be optimized into one constant number anyway.</p> <p>Or, if you wanna be extra-careful and/or don't know if you will access parts which you haven't written to, you could use:</p> <p><code>calloc(number_of_elements, sizeof(type))</code></p> <p>The difference to <code>malloc</code> is that <code>calloc</code> makes sure you get nulled memory (on most implementations by serving you a pointer to a special <em>copy-on-write</em> zeroed memory page of the system), as well as returning memory aligned to <code>sizeof(type)</code> (malloc will normally also return aligned memory, but in the case of malloc, it will probably be aligned to the largest alignable value)</p> <hr> <p>As bounds checking has been mentioned in a different answer: You could have a look at gcc <strong>mudflap</strong> extension - it doesn't exactly do bounds checking, but many other memory related things, and IMHO is one of the easiest things to set up besides <strong>valgrind</strong> (which doesn't need any setup, but unfortunately doesn't always work)</p>

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