warning: unresolved external symbol

would appreciate if someone can tell me c and asembly code in the Uvision3?
my source code as follows

#include <reg51.h>
#include <C51S.LIB>
#include<stdio.h>
#include "setUpSerPort.h"



void main()
 {

  idata unsigned  char i;
  unsigned char cur[20];
//  extern x;

  for( i = 0; i < 20; i++)
   {
        #pragma asm
    MOV DPTR, #0X1234
    MOV   A, #0X30
    MOVC A, @A+DPTR
        #pragma endasm
  }
}

when compiled it shows following warnings
linking...
*** WARNING L1: UNRESOLVED EXTERNAL SYMBOL SYMBOL: ?C_START MODULE: STARTUP.obj (?C_STARTUP)
*** WARNING L2: REFERENCE MADE TO UNRESOLVED EXTERNAL SYMBOL: ?C_START MODULE: STARTUP.obj (?C_STARTUP) ADDRESS: 082AH
Program Size: data=30.0 xdata=0 code=47
"test1" - 0 Error(s), 4 Warning(s).

please suggest the solution Thank You