“ unsupported for`ljmp' ” error while compiling

[1eftHer0]

I'm using gmake to compile code, but I'm stuck on this error message:
http://ocw.mit.edu/courses/electrical-e ... handout.gz
(this code from MIT.OCW)

Code: Select all

+ as kern/entry.S
kern/entry.S: Assembler messages:
kern/entry.S:55: Error: unsupported for `ljmp'
gmake: * [obj/kern/entry.o] Error 1

How can I fix it?

[Combuster]

Use a 32-bit toolchain rather than a 64-bit one.

[1eftHer0]

ok Combuster, I'm try to change GNUmakefile add -m32 optional in gcc that's work. its compiling pass many file but stuck in this error message(stuck in boot folder).

Code: Select all

+ ld boot/boot
ld: i386 architecture of input file `obj/boot/boot.o' is incompatible with i386:x86-64 output
ld: i386 architecture of input file `obj/boot/main.o' is incompatible with i386:x86-64 output
ld: obj/boot/boot.o: file class ELFCLASS32 incompatible with ELFCLASS64
ld: final link failed: File in wrong format
gmake: *** [obj/boot/boot] Error 1

[xenos]

Use a linker script with OUTPUT_FORMAT(elf32-i386) and OUTPUT_ARCH(i386) - or follow Combuster's advice and use a 32 bit toolchain instead of a 64 bit one.

[Creature]

Are you srue you added -m32 to the compiler AND made sure the linker is creating a 32-bit file as well? It seems as if the error is caused by GCC creating 32-bit object files and the LD trying to use them to create a 64-bit executable.