title: give structure offset attribute to assembler
body: <p>how can I send the offset of a C struct to en assembly code ?
  For example</p>
  
  <p>In my C code I have</p>
  
  <pre><code>typedef struct
  {
    unsigned int a;
    unsigned int b;
  } CMyStruct;
  </code></pre>
  
  <p>I send to an ASM function a pointer of a CMyStruct structure
  Let suppose that my pointer is into R0</p>
  
  <p>To access to a and b attribute I need to do that.</p>
  
  <pre><code>ldr      r1, [r0, #0] // read a
  ldr      r2, [r0, #4] // read b
  </code></pre>
  
  <p>Is there anyway to not specify #0 and #4 as contant value ?
  Something like</p>
  
  <pre><code>ldr      r1, [r0, CMyStruct.a] // read a
  ldr      r2, [r0, CMyStruct.b] // read b
  </code></pre>
  
  <p>Thank's
  Etienne</p>