16-bit linking under linux

Question

I'm using NASM Assembler under linux when I use the command "nasm -f elf -l hello.lst hello.asm" it works fine but when linking with gcc "gcc -o hello hello.o" it generates an error :

hello.asm:(.text+0x4): relocation truncated to fit: R_386_16 against `.data' collect2: ld returned 1 exit status

I learned that this is some problem with gcc and 16-bit

any solutions ?

Does your gcc installation have a 16-bit default runtime lib? — Peter G., Dec 04 '10 at 19:04
Looks like you're missing pieces of your cross-compiler toolchain. — Ben Voigt, Dec 04 '10 at 23:58

score 3 · Accepted Answer · answered Dec 04 '10 at 20:51

3

Linux doesn't even have a 16-bit subsystem - even if you got gcc to link it, you still couldn't execute it! Why don't you just use .bits 32?

answered Dec 04 '10 at 20:51

Fabian Giesen

3,231
16
16

2

If you need to write 16-bit code for homework, I recommend doing so in DOSBox and using a DOS linker (NASM had regular DOS releases at some point, not sure if it still does). I'm not aware of *any* port of GCC / binutils to x86 16-bit, no matter the OS (closest thing is DJGPP, but that's still 32-bit and requires a DOS extender). – Fabian Giesen Dec 06 '10 at 06:43

score 0 · Answer 2 · edited Jul 03 '15 at 23:29

I faced the same situation a few years ago and again this year.

Two ways to deal with it are:

Write your own 16-bit friendly linker (you need to parse .rel.text section at least).
Use a base symbol (or symbols) to calculate the absolute addresses manually (the .rel sections are still created, but can be removed). However, this method is very error prone.

I always end up doing 2, but I should probably make time to write a linker (or patching GNU ld...).

16-bit linking under linux

2 Answers2