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OUTPUT_FORMAT("BINARY")
ENTRY(main)
phys = 0x2000;
SECTIONS
{
  .text phys : AT(phys) {
    code = .;
    *(.text)
    *(.rodata)
    . = ALIGN(4096);
  }
  .data : AT(phys + (data - code))
  {
    data = .;
    *(.data)
    . = ALIGN(4096);
  }
  .bss : AT(phys + (bss - code))
  {
    bss = .;
    *(.bss)
    . = ALIGN(4096);
  }
  end = .;
}

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ld -T link.ld -o kernel.bin main.o
dd if=kernel.bin of=floppy.img seek=1 bs=512 count=1 conv=notrunc (seeking  1 because bootloader resides at sector 1 )
qemu -fda floppy.img 

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ld -e _main -Ttext 0x20000 -o kernel.o main.o 
ld -i -e _main -Ttext 0x20000 -o kernel.o main.o 
objcopy -R .note -R .comment -S -O binary kernel.o kernel.bin
dd if=kernel.bin of=floppy.img seek=1 bs=512 count=1 conv=notrunc
qemu -fda floppy.img 

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#ifndef _CODE16GCC_H_
#define _CODE16GCC_H_
__asm__(".code16gcc\n");
#endif
/*
 * A simple bootloader skeleton for x86, using gcc.
 *
 * Prashant Borole (boroleprashant at Google mail)
 * */
#include "code16gcc.h" 
/* XXX these must be at top */
__asm__ ("jmp main");
 
 
#define __NOINLINE  __attribute__((noinline))
#define __REGPARM   __attribute__ ((regparm(3)))
#define __NORETURN  __attribute__((noreturn))
 
/* BIOS interrupts must be done with inline assembly */
void    __NOINLINE __REGPARM print(const char   *s){
	int i ;
        for(i=0;s[i];i++)
        {
        	char ch = s[i];
        	__asm__("mov $0x0E ,  %ah");
                __asm__("xor %bh ,  %bh");
                __asm__("mov $0xEF ,  %bl");
		__asm__("mov %0 , %%al ;": : "r"(ch):"%eax");
                __asm__("or %al , %al");
                __asm__("int $0x10");

        }
        return ;
}
/* and for everything else you can use C! Be it traversing the filesystem, or verifying the kernel image etc.*/
 
void __NORETURN main(){
   print("woo hoo!\n");
  		char ch='A';
                __asm__("mov $0x0E ,  %ah");
                __asm__("xor %bh ,  %bh");
                __asm__("mov $0xEF ,  %bl");
		__asm__("mov %0 , %%al ;": : "r"(ch):"%eax");
                __asm__("or %al , %al");
                __asm__("int $0x10");
                
    while(1);
}

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it inserts a call like this mov byte ptr ds[edi] , al ; And this results in making a call which is far into the memory than what real mode can refer.