cross compiler and grub
Posted: Wed Sep 05, 2007 3:00 pm
I just built the cross compiler on the wiki page but when I try to make a hello world kernel GRUBs tell me its not a valid file format...
at first i was using aout format for NASM but the linker for the cross compiler told me that it didn't recognize that file format... i changed format for the assembly file to elf and the linker worked but GRUB says invalid file format..
any help ?
I know the code is right because I've compiled it in the past using linux and tested it... only change is i used aout file format rather than elf when it worked... but I can't do that as the cross compiler ok the wiki is for elf file format...
(On mac os x now)
ASM file
c file
edit:
Nevermind... fixed it =]
yet another silly mistake by the very clumsy OS dever R2
I was missing the grub header
at first i was using aout format for NASM but the linker for the cross compiler told me that it didn't recognize that file format... i changed format for the assembly file to elf and the linker worked but GRUB says invalid file format..
any help ?
I know the code is right because I've compiled it in the past using linux and tested it... only change is i used aout file format rather than elf when it worked... but I can't do that as the cross compiler ok the wiki is for elf file format...
(On mac os x now)
ASM file
Code: Select all
[BITS 32]
[global start]
[extern main] ; this is in the c file
start:
call main
cli ; stop interrupts
hlt ; halt the CPU
Code: Select all
int main(void)
{
char *str = "Hello, world", *ch;
unsigned short *vidmem = (unsigned short*) 0xb8000;
unsigned i;
for (ch = str, i = 0; *ch; ch++, i++)
vidmem[i] = (unsigned char) *ch | 0x0700;
for (;;);
}
Nevermind... fixed it =]
yet another silly mistake by the very clumsy OS dever R2
I was missing the grub header