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ld -T linker.ld -o kernel.bin start.o kernel.main.o

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kernel.main.o: In function `main':
/home/daniel/N3OS/OLD/1.0/kernel.main.d:13: undefined reference to `_d_criticalenter'
/home/daniel/N3OS/OLD/1.0/kernel.main.d:13: undefined reference to `_d_criticalexit'
/home/daniel/N3OS/OLD/1.0/kernel.main.d:16: undefined reference to `_d_criticalenter'
/home/daniel/N3OS/OLD/1.0/kernel.main.d:16: undefined reference to `_d_criticalexit'
/home/daniel/N3OS/OLD/1.0/kernel.main.d:17: undefined reference to `_d_criticalenter'
/home/daniel/N3OS/OLD/1.0/kernel.main.d:17: undefined reference to `_d_criticalexit'
kernel.main.o: In function `kernel.main._D6kernel4main9__modinitFZv':
/home/daniel/N3OS/OLD/1.0/kernel.main.d:1: undefined reference to `_Dmodule_ref'
/home/daniel/N3OS/OLD/1.0/kernel.main.d:1: undefined reference to `_Dmodule_ref'

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global start
extern main        ; Allow main() to be called from the assembly code
extern start_ctors, end_ctors, start_dtors, end_dtors
 
MODULEALIGN        equ        1<<0
MEMINFO            equ        1<<1
FLAGS              equ        MODULEALIGN | MEMINFO
MAGIC              equ        0x1BADB002
CHECKSUM           equ        -(MAGIC + FLAGS)
 
section .text      ; Next is the Grub Multiboot Header
 
align 4
MultiBootHeader:
       dd MAGIC
       dd FLAGS
       dd CHECKSUM
 
STACKSIZE equ 0x4000  ; 16k if you're wondering
 
static_ctors_loop:
   mov ebx, start_ctors
   jmp .test
.body:
   call [ebx]
   add ebx,4
.test:
   cmp ebx, end_ctors
   jb .body
 
start:
       mov esp, STACKSIZE+stack
 
       push eax
       push ebx
 
       call main
 
static_dtors_loop:
   mov ebx, start_dtors
   jmp .test
.body:
   call [ebx]
   add ebx,4
.test:
   cmp ebx, end_dtors
   jb .body
 
 
cpuhalt:
       hlt
       jmp cpuhalt
 
section .bss
align 32
 
stack:
      resb      STACKSIZE

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module kernel.main;

extern(C) void main(uint magic, uint addr) {

        int ypos = 0; //Starting points of the cursor
	int xpos = 0;
	const uint COLUMNS = 80; //Screensize
	const uint LINES = 24;

	ubyte* vidmem = cast(ubyte*)0xFFFF8000000B8000; //Video memory address

	for (int i = 0; i < COLUMNS * LINES * 2; i++) { //Loops through the screen and clears it
			synchronized {*(vidmem + i) = 0;}
	}

	synchronized {*(vidmem + (xpos + ypos * COLUMNS) * 2) = 'D' & 0xFF;} //Prints the letter D
	synchronized {*(vidmem + (xpos + ypos * COLUMNS) * 2 + 1) = 0x07;} //Sets the colour for D to be light grey (0x07)

	for (;;) { //Loop forever. You can add your kernel logic here
	} 
}

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OUTPUT_FORMAT(elf32-i386)
ENTRY (start)

SECTIONS{
    . = 0x00100000;

    .text :{
        code = .; _code = .; __code = .;
        *(.text)
        *(.rodata)
    }

    .rodata ALIGN (0x1000) : {
        *(.rodata)
    }

    .data ALIGN (0x1000) : {
        data = .; _data = .; __data = .;
        *(.data)
        start_ctors = .; *(.ctors)   end_ctors = .;
        start_dtors = .; *(.dtors)   end_dtors = .;
    }

    .bss : {
        sbss = .;
        bss = .; _bss = .; __bss = .;
        *(COMMON)
        *(.bss)
        ebss = .;
    }
    end = .; _end = .; __end = .;
}

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import std.stdio;