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AusZero wrote:Although I haven't been OSDeving for a long time and forgot some of it, I may be able to help a little. I think your problems may lie in your "link.ld" file. Try commenting your " OUTPUT_FORMAT("binary") " line and try changing your "ENTRY(mymain)" to "ENTRY(start)". Remember that I don't know much about this, but that may work.

ENTRY(main)
phys = 0x00100000;
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 =.;
}

AusZero wrote:In my operating system, I didn't have an output format in the "link.ld" file, and it worked without any problems. Also, the "ENTRY(main)" should be "ENTRY(start)".

gcc -T link.ld -o kernel.bin start.o //usr/lib/gcc/i686-pc-linux-gnu/bin/ld: cannot find code
//collect:ld returned 1 exit status

gravaera wrote:I'm not doing my kernel in C, however, I believe you're missing a few necessary command line options to GCC that ensure it doesn't try to link in libraries from the native OS.

Why not look around the wiki (I can't remember where exactly, but I do remember Solar listing a bunch of Comm. Line options for GCC in his makefile tutorial) and see which command line options apply for C?

I know for sure you're missing -ffreestanding, and that it's not purely a good practice to try passing your object file outputs through GCC to get them to the linker...why not just pass the objects to the linker itself?

And there's something wrong with the way yoo go about this whole thing:

First you assemble a relocatable object file, start.o; Then you compile main.o; Then you link (through GCC, which is not really standard practice) together start.o, and nothing else into kernel.bin.

What you should do is link together the relocatable object files to create an executable image like so:

Code: Select all

ld -T ./link.ld -o kernel.bin main.o start.o

If you replace the last line with the ...gcc -T... you should get a link, assuming you get the command line flags in order to stop LD from trying to link in libGCC.

I would recommend taking some time off to understand Linking and do some reading on Relocatable, Shared, and Executable object files. Wikipedia has some good info on that.

-Good luck
gravaera