Trouble with bootloader writed in C language

hello.I try to write bootloder in C language.The bootloder (boot()) in boot.c file comes with a application project. In the project ,the main funcion ,of course,don't call boot().

The result is in the project map file ,the section "boot_loader" set for boot function is lost.I think the compiler has ignore the boot function.I want to know how to solve this problem.

the following is my boot.c and link.cmd:

/*******************************
           boot.c
*******************************/
#include "c6x.h"
#include "c6747.h"

#define NAND_BASE                  0x62000000  // SNAND.CS0 BASE
#define NAND_CLE_PTR        *( volatile Uint8* )( NAND_BASE + 0x10 )
#define NAND_ALE_PTR        *( volatile Uint8* )( NAND_BASE + 0x08 )
#define NAND_CMD( cmd )     NAND_CLE_PTR = cmd;
#define NAND_ADDR_4( addr ) NAND_ALE_PTR = (addr >> 0) & 0xff;

#define CODE_ADDR   00800400h

extern far c_int00(void);
extern far unsigned int text_size; 

#pragma CODE_SECTION(boot,"boot_loader");
void boot(void)
{
 Uint32 i, j;
 Uint16 flag = 0;
 register int code_count=0;
 volatile Uint32 *dst8 =(volatile Uint32 *)0x00800400;
 Uint32 src=0x400;
  
 //AEMIF configure
 AEMIF_A2CR = 0x0886632C;
 AEMIF_NANDFCR = 0x00000002;

 // Code Copy
  
    for ( i = 0 ; i < 4 ; i++ )//copy 4 pages
    {

        NAND_CMD( 0x00 );           // Read page
        NAND_ADDR_4( src );
  NAND_CMD(0x30 );

  // Read MAIN array
  for ( j = 0 ; j < 2*1024 ; j++ )
           {
           *dst8++ = 0x62000000;
           code_count++;
           if(code_count==text_size)
            {
      flag = 1;
            break;
            }
     }           
  if(!flag )
  src += 0x1000;//4K
    }
    c_int00();

}   

/*******************************
            link.cmd
******************************/
-c
-heap  0x1000
-stack 0x1000

MEMORY
{
    BOOTRAM:       o = 00800000h   l = 00000400h  //1K
    IRAM:          o = 00800400h   l = 0083FFFFh
    FLASH_BOOT:    o = 0x62000000  l = 00000400h
    FLASH_REST:    o = 0x62000400  l = 63FFFFFFh                          

                                                             
}

SECTIONS
{
 .boot_loader   :   load = FLASH_BOOT, run = BOOTRAM   
                                                                  
    /* Initialized User Code Section */
    .text    : load = FLASH_REST, run = IRAM
     SIZE(_text_size)
          
    .cinit     >     IRAM
    .const      >       IRAM
    .stack      >       IRAM
    .bss        >       IRAM
    .data       >       IRAM
    .far        >       IRAM
    .switch     >       IRAM
    .sysmem     >       IRAM
    .cio        >       IRAM
 .vectors >  IRAM, RUN_START(_ISTP_START)
}