Re: binutils woes

[Russell King <rmk+lkml@arm.linux.org.uk>]

On Thu, Jul 01, 2004 at 03:21:34PM -0700, Andrew Morton wrote:
> Russell King <rmk+lkml@arm.linux.org.uk> wrote:
> >
> > Essentially, we run 'nm' against the object, and look for any line
> > which matches the pattern '^ *U '.  With this, a failing output looks
> > like:
> > 
> >   LD      init/built-in.o
> >   LD      .tmp_vmlinux1
> > ldchk: .tmp_vmlinux1: final image has undefined symbols:
> >   SIZEOF_MACHINE_DESC
> 
> What is the user supposed to do when this happens?

Report it as an error to the most appropriate forum.  Then it becomes
a hunt for why the symbol is undefined.

Sorry, afaics it's not possible to do this any better.

To illustrate the severity of the problem better, the following
program:

        .globl  _start
_start:
        add     r0, r0, #UNDEFINED_SYMBOL
        mov     pc, lr

will successfully assemble and link on ARM, and is in fact runnable
despite having a symbol table of the following:

$ arm-linux-nm t
00008074 t $a
0001007c A __bss_end__
0001007c A _bss_end__
0001007c A __bss_start
0001007c A __bss_start__
0001007c D __data_start
0001007c A _edata
0001007c A _end
0001007c A __end__
00008074 T _start
         U UNDEFINED_SYMBOL


-- 
Russell King
 Linux kernel    2.6 ARM Linux   - http://www.arm.linux.org.uk/
 maintainer of:  2.6 PCMCIA      - http://pcmcia.arm.linux.org.uk/
                 2.6 Serial core