not used functions linked and declares XDATA for local vars

Hello,

I have detected that some functions like this one are using their own XDATA space instead of using the XDATA_GROUP for local purposes:

for example this one:

void zmemcpy2(UINT8 *dst,const UINT8 *src, UINT32 len)
{

      --dst;   --src;
       while (len--)
       {
          *(++dst) = *(++src);
   }
}

then this is the line in the m51 file:

XDATA   82C2H     000AH     UNIT         ?XD?_ZMEMCPY2?LIB

so then Im wasting ten bytes of global data space for just a memcopy. Why is this happening?

And here it is another weird thing: this function is never used by the rest of the program. It is compiled, but should not be linked.
any idea?

thanks in advance...