[Fwd: Re: [Re: [avr-gcc-list] Allocating variables to a fixed address]]

[Robert von Knobloch]

On Wed, May 13, 2009 at 01:16:31PM +0200, Robert von Knobloch wrote:

> 
> Curiously I could not use e.g.
> 
> asm ("test_pgm_read_byte:        jmp pgm_read_byte");
> "undefined reference to 'pgm_read_byte'" although it is defined and in
> scope.
> 
> Where pgm_read_byte is a library function from avr-libc.
> I had to supply a stub function of my own [flash_read_byte()] to, in
> turn,  call pgm_read_byte()
> and then it was happy :-)

Did you have a ".global pgm_read_byte" in your assembler code?    ;-)
That is needed to make the symbol public across compile units, and I
can't see it in your example.

Could you please forward this to the list also, because I'm still
not able to post.

mfG,
Erik

OK Erik -forwarded.
No, I didn't - but now fixed.
Thanks,

Robert