LD makes output huge!

[mr. x2]

I'm trying to compile my OS under Linux, in Windows the kernel.bin will be ~40 kb, but in Linux, it will be ~1mb! All the object files are correct, but the output of ld is huge.
This is how I link:
ld -T kernel.ld
This is my linker script:

Code: Select all

OUTPUT_FORMAT("binary")
ENTRY(start_stub)
OUTPUT("kernel.bin")

INPUT(kinit.o)
INPUT(kints.o)
INPUT(ints.o)
INPUT(driver_keyboard.o)
INPUT(driver_floppy.o)
INPUT(kernel.o)
INPUT(app_console.o)
INPUT(io.o)
INPUT(pic.o)
INPUT(idt.o)
INPUT(panic.o)
INPUT(doprintf.o)
INPUT(queue.o)
INPUT(string.o)
INPUT(memory.o)
INPUT(math.o)
INPUT(dma.o)
INPUT(driver_pefs.o)
INPUT(timer.o)
INPUT(mem_manager.o)
INPUT(driver_layers.o)
INPUT(sched.o)
INPUT(driver_FAT.o)
INPUT(driver_fs.o)
INPUT(driver_dev.o)
INPUT(config_parser.o)


SECTIONS  {
  .text 0x100000: {
    *(.text)
  }
  .data  : {
    *(.data)
  }
  .bss  :  {
    *(.bss)
  }

  kernel_end = .;
}

[Candy]

I'm trying to compile my OS under Linux, in Windows the kernel.bin will be ~40 kb, but in Linux, it will be ~1mb! All the object files are correct, but the output of ld is huge.

You probably include a huge section of zeroes. Can you post the first 10 lines of a "hexdump -C filename" of the output file?

[Pype.Clicker]

that suggests something wrong in your linker script that made it write 1MB of zeroes rather than setting the virtual address to 1MB ...

Do you have . = 0x00100000 somewhere ?

[mr. x2]

that suggests something wrong in your linker script that made it write 1MB of zeroes rather than setting the virtual address to 1MB ...

Do you have . = 0x00100000 somewhere ?

Nope

[mr. x2]

I'm trying to compile my OS under Linux, in Windows the kernel.bin will be ~40 kb, but in Linux, it will be ~1mb! All the object files are correct, but the output of ld is huge.

You probably include a huge section of zeroes. Can you post the first 10 lines of a "hexdump -C filename" of the output file?

If I understood hexdump right, there should be alot of zeroes right at 0x00000100 to 0x000f4240...

[Someone]

I suggest you to use this linker script:

SECTIONS {
.text 0x100000: {
*(.text) *(.rodata)
}
.data : {
*(.data)
}
.bss : {
*(.bss)
}

kernel_end = .;
}

i hope it works

[virusx]

hi,

I hope this will fixyour problem.
ld -Ttext 0x100000 -Txyz.ld ...

regards

[NoNaMe]

Hi,

I had the same problem when I declared an Array or a Pointer. This was because the following was not in my link script:

*(.rodata)

So the following link script should work fine:

Code: Select all

OUTPUT_FORMAT("binary")
ENTRY(start_stub)
OUTPUT("kernel.bin")

INPUT(kinit.o)
INPUT(kints.o)
INPUT(ints.o)
INPUT(driver_keyboard.o)
INPUT(driver_floppy.o)
INPUT(kernel.o)
INPUT(app_console.o)
INPUT(io.o)
INPUT(pic.o)
INPUT(idt.o)
INPUT(panic.o)
INPUT(doprintf.o)
INPUT(queue.o)
INPUT(string.o)
INPUT(memory.o)
INPUT(math.o)
INPUT(dma.o)
INPUT(driver_pefs.o)
INPUT(timer.o)
INPUT(mem_manager.o)
INPUT(driver_layers.o)
INPUT(sched.o)
INPUT(driver_FAT.o)
INPUT(driver_fs.o)
INPUT(driver_dev.o)
INPUT(config_parser.o)

SECTIONS
{
   .text 0x100000:
   {
      code = .; _code = .; __code = .;
      *(.text) *(.rodata)
      . = ALIGN(4096);
   }
   .data :
   {
      data = .; _data = .; __data = .;
      *(.data)
      . = ALIGN(4096);
   }
   .bss :
   {
      bss = .; _bss = .; __bss = .;
      *(.bss)
      . = ALIGN(4096);
   }
   end = .; _end = .; __end = .;
}

Thanks to Someone to post his link script. It was there I saw the solution.

Regards