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you dont needx to build gcc, just binutils.

df wrote: you dont needx to build gcc, just binutils.

hmm well I am still getting this error message:

main.o(.text+0x23):main.c: undefined reference to `__alloca'
main.o(.text+0x28):main.c: undefined reference to `___main'
main.o(.text+0x34):main.c: undefined reference to `_printf'

I'm assuming it's because their object files meant to be linked to pe, as elf doesn't like symbols with an underscore.

yeah elf has this underscore thing going on, pe does not.

ld: warning: cannot find entry symbol _start; defaulting to 08048080
main.o(.text+0x23):main.c: undefined reference to `__alloca'
main.o(.text+0x28):main.c: undefined reference to `___main'
main.o(.text+0x34):main.c: undefined reference to `_printf'

my guess is your are trying to link against the libc with an os kernel, which is a no-no.

1st error about enrtry point is easy fixed with -E option in ld.

removed anything to do with libc and used the -E switch, I still get this:

main.o(.text+0x23):main.c: undefined reference to `__alloca'
main.o(.text+0x28):main.c: undefined reference to `___main'

coz you still compiled it like a standard program ::) you need to compile it standalone...

you need tyo compile with

gcc -nostdlib -nostdinc++ -nostdinc -fno-builtin -fsigned-char -ffreestanding

no change

BTW This is the first time I have ever tried to use gcc. So am very new to this.

Are _alloca and __main symbols defined in the code you are compiling (meaning its not looking for something in an external library) ?

_alloca is in libgcc. This is necessary in gcc 3.x, but luckily it doesn't contain any OS-specific calls. You might have to provide your own empty __main.