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    <p>Nothing, they work in the same way. Here a short example:</p> <pre><code>int WithArray(int array[10]) { return array[1] + array[2]; // breakpoint 1 } int WithPointer(int *pointer) { return *(pointer + 1) + *(pointer + 2); // breakpoint 2 } void main() { int array[] = {0,1,2,3,4,5,6,7,8,9}; int b = WithPointer(array); int a = WithArray(array); printf("a = %d\nb = %d\n", a, b); } </code></pre> <p>Ok, I'll call WithPointer() first, just in case WIthArray() copies the array on the stack. Here's the stack at the second breakpoint:</p> <pre><code>Breakpoint 2, WithPointer (pointer=0xbffff418) at prova.c:10 10 return *(pointer + 1) + *(pointer + 2); (gdb) x/20x ($esp - 8) 0xbffff404: 0x08049ff4 0xbffff418 0xbffff448 0x0804843b 0xbffff414: 0xbffff418 0x00000000 0x00000001 0x00000002 0xbffff424: 0x00000003 0x00000004 0x00000005 0x00000006 0xbffff434: 0x00000007 0x00000008 0x00000009 0x08048460 0xbffff444: 0x00000000 0xbffff4c8 0x00144bd6 0x00000001 </code></pre> <p>As expected, there's our pointer (0xbffff418, the first value on the second line) and, right after that, array[] (which is on main()'s stack frame). Let's check the stack inside WithArray():</p> <pre><code>(gdb) continue Continuing. Breakpoint 1, WithArray (array=0xbffff418) at prova.c:5 5 return array[1] + array[2]; (gdb) x/20x ($esp - 8) 0xbffff404: 0x08049ff4 0xbffff418 0xbffff448 0x08048449 0xbffff414: 0xbffff418 0x00000000 0x00000001 0x00000002 0xbffff424: 0x00000003 0x00000004 0x00000005 0x00000006 0xbffff434: 0x00000007 0x00000008 0x00000009 0x08048460 0xbffff444: 0x00000003 0xbffff4c8 0x00144bd6 0x00000001 </code></pre> <p>Exactly the same thing! So there's no difference about how they're passed to functions. And they're handled in the same way too, look:</p> <pre><code>(gdb) disass WithPointer Dump of assembler code for function WithPointer: 0x080483cc &lt;+0&gt;: push %ebp 0x080483cd &lt;+1&gt;: mov %esp,%ebp 0x080483cf &lt;+3&gt;: mov 0x8(%ebp),%eax # get base address 0x080483d2 &lt;+6&gt;: add $0x4,%eax # compute offset 0x080483d5 &lt;+9&gt;: mov (%eax),%edx # dereference and get val. 0x080483d7 &lt;+11&gt;: mov 0x8(%ebp),%eax # base address 0x080483da &lt;+14&gt;: add $0x8,%eax # offset (2 * sizeof(int)) 0x080483dd &lt;+17&gt;: mov (%eax),%eax # get *eax 0x080483df &lt;+19&gt;: lea (%edx,%eax,1),%eax # tricky way to add them 0x080483e2 &lt;+22&gt;: pop %ebp 0x080483e3 &lt;+23&gt;: ret End of assembler dump. (gdb) disass WithArray Dump of assembler code for function WithArray: 0x080483b4 &lt;+0&gt;: push %ebp 0x080483b5 &lt;+1&gt;: mov %esp,%ebp 0x080483b7 &lt;+3&gt;: mov 0x8(%ebp),%eax # first element of array 0x080483ba &lt;+6&gt;: add $0x4,%eax # move to the second 0x080483bd &lt;+9&gt;: mov (%eax),%edx # and get its value 0x080483bf &lt;+11&gt;: mov 0x8(%ebp),%eax # base of array 0x080483c2 &lt;+14&gt;: add $0x8,%eax # compute address of second 0x080483c5 &lt;+17&gt;: mov (%eax),%eax # element and get load it 0x080483c7 &lt;+19&gt;: lea (%edx,%eax,1),%eax # compute sum 0x080483ca &lt;+22&gt;: pop %ebp 0x080483cb &lt;+23&gt;: ret End of assembler dump. </code></pre> <p>Codes are identical. Note that the array is handled as a pointer.</p>
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