Have some linking errors with ld: "relocation truncated to fit"

[unicornx]

Hello, I have some errors then linking with ld:

I am writing a simple 16-bit real-mode demo code to print some char on screen, and assemble with nasm:

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[org 0x7c00]
mov ah, 0x0e

mov al, "1"
int 0x10
mov al, the_secret ; just want to demo a wrong usage
int 0x10

mov al, "2"
int 0x10
mov al, [the_secret] ; correct usage
int 0x10

jmp $ ; infinite loop

the_secret:
    db "X"

times 510-($-$$) db 0
dw 0xaa55

I use

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nasm -f bin bootsect.asm -o bootsect.bin, and it's ok

Then I tried to use gdb to trace the code, so I tried following:

I removed first line

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[org 0x7c00] due to nasm will report "error: unrecognised directive [org]"

So I use ld to assign the load address with "-Ttext=0x7c00", following are my commands:

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$ nasm bootsect.asm -f elf -g -F dwarf -o bootsect.o
$ i386-elf-ld -Ttext=0x7c00 bootsect.o -o bootsect.elf

But ld reports error:

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bootsect.o:bootsect.asm:6:(.text+0x7): relocation truncated to fit: R_386_8 against `.text'

Checked code and I see this code line causes the problem

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mov al, the_secret

I know it is not good writing, but I would have to keep this code due to I just want to write a demo and I know it could pass build with "nasm -f bin". So my question is how to pass building with ld so I can use gdb to trace this demo? Thanks in adv.

[debs3759]

"the_secret" is a memory address/offset, so will not fit in an 8-bit register. I'm surprised it assembled, sounds like a bug to me.

[unicornx]

Do you mean it is a bug for nasm? I am using NASM version 2.11.08

[debs3759]

It sounds like a nasm bug if it assembles a 16/32/64 bit number into an 8-bit register. It shouldn't be possible.