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I'm trying to link the kernel entry (written in asm) and the kernel (written in C) however I get the following warning: The warning doesn't sound good but I still get a linked binary kernel.bin file. I think the linked file is fine; I haven't tested it because my home made boot loader doesn't seem to like it. It executes the code but prints random text, not the stuff I specified in the data section. I think I know how to solve this problem. I found a article in the forum on a similar issue. However, my primary concern is this warning. Is this warning something I should be concerned about and if so how could I tell ld to output i386 binary?

Yours,
Kenneth

I'll repost later this afternoon when I get home and can check my linker script (I compiled 32-bit in a 64-bit environment before I reinstalled linux).

It's pretty much the same flag as GCC - In gcc it's just -m32.

This should work.

JamesM

I think these are your options:
1) put something like (from the wiki) at the top of your linker script, or
2) pass -m<emu> to ld, where available <emu> options are in the first lines of the output of "ld --verbose". Mine has "elf_i386", but this may depend on ld version and compilation options.

For normal programs, there's also
3) pass -m32 to gcc when linking
but for an OS you're probably using ld directly.

All of these specify ld's output format as

Thanks guys
I think that solved the problem! However, now there is another problem, which I thought I knew the answer to.
My boot loader loads all 10 cylinders of the floppy onto memory starting at 0x7e00. Doing an objdump of my floppy I found that my second stage loader (i guess it's more like a kernel_entry) starts from 0x04400. Everytime I re-format my floppy and copy a file, the first file that is coppied to an empty floppy is saved in 0x04400 an on. So I reasoned that that is where it was going to be, thus after reading the floppy into mem, I just had to jump to 0x7e00+(0x04400-0x200) [subtract the 512 of the boot sector from the 0x04400 because everything but the 1st sector is read into mem] to execute the second stage boot loader. This was fine while my second stage boot loader was just 1 asm file. However, when I started writing the kernel in C and linked it to the second stage boot loader, things went all wrong. I did several binary dumps of my floppy and found out how to get to the code of my second stage boot loader( i think it was something like [linked phys address] + [0x4400] - [0x200]). So I rewrote my boot sector and tried running my "os" and found out that the code was executed but the strings that I wanted to have printed out onto the screen didn't get printed. Instead I got weird characters (S = S=): I finally came to the conclusion that I am linking my object files wrong, however I am not sure of the exact problem, so I can figure out how to fix it. I read an article on a similar issue but that didn't help. Does anyone know what the problem is and how to fix it? Thanks.

Yours,
Kenneth

Sounds like the address you load your kernel and the address your linker thinks it will get loaded at are different. Add "-Ttext <address>" to your ld command line or modify your linker script to link at the right address.

Thanks! That was simple wasn't it. Sorry for my stupidity.
because I was jumping to 0xC00 I just had to change the ld script to link the kernel at 0xC00.

Yours,
Kenneth