Cross compilation

Fernando Apesteguía fernando.apesteguia at
Wed Dec 6 09:11:49 UTC 2006

On 11/28/06, Steven W. Orr <steveo at> wrote:
> On Tuesday, Nov 28th 2006 at 18:50 +0100, quoth Fernando Apesteguía:
> =>Helo list,
> =>
> =>I'm using FC6 for x86_64. I need to compile a program for linux 32
> =>bits. I tried with the -m32 flag to gcc, but I got:
> =>
> =>core_recv.c:(.text+0x130): undefined reference to `__umoddi3'
> =>
> =>and tons of ld warnings:
> =>
> =>/usr/bin/ld: warning: i386 architecture of input file `main.o' is
> =>incompatible with i386:x86-64 output
> =>
> =>I searched in Google, but couldn't find the solution. For the
> =>undefinded references I suppose it is because some missing i386
> =>libraries right?
> =>
> =>And what about the other things? How can I compile a 32 bit
> =>application under a 64 bit system?
> Sorry, but you need to create a seperate cross compiler. You're running on
> a your native system and you're trying to create an executable for another
> machine. So you need a whole different toolchain. The easiest way *might*
> be to use buildroot (just google it please) but the point is that you need
> a whole different setup to target a different machine. gcc, binutils,
> libc, gdb, the whole banana, and the whole thing has to be specific to the
> version of the kernel you're running on the target system. Just don't even
> *try* to figgah out options for your current system. It won't work.
> --
> fedora-list mailing list
> fedora-list at
> To unsubscribe:

Hi again,

Yes, the question is that I could make a chroot, but I would prefer
not to do it for several reasons (hard disk space is one of them).

The compiler does his work, the .o are all:
ELF 32-bit LSB relocatable, Intel 80386, version 1 (SYSV), not stripped

but then, the ld doesn't manage the situation. The supported emulations are
elf_x86_64 elf_i386 i386linux

I tried with the last two and it didn't work...
The program uses the common standard functions like printf and strcpy
and some other features of libreadline.

I have both i386 and x86_64 (and again both, binaries and devel
packages) installed in my system.

Any more clues?

Thanks in advance

More information about the users mailing list