Re: [avr-gcc-list] Someting I don"t understand with PGM_P et pgm_read_byte_far()

[E. Weddington]

Bernard Fouché wrote:

> Hi there.
>
> I'm trying to compile for ATMEGA128. I sometimes need to use 
> pgm_read_byte(). For instance with:
>
> uint8_t  f(PGM_P p)
> {
>    return pgm_read_byte_far(p);
> }
>
> When doing so, the compiler says:
> "warning: cast from pointer to integer of different size".
>
> So it appears that, even for an ATMEGA128, a PGM_P data type is a 16 
> bits pointer. 

That is correct.

> How can I tell the compiler that 'p' is a 32 bits address in flash in 
> a proper way?
Use the correct type.

uint8_t  f(uint32_t p)
{
  return pgm_read_byte_far(p);
}


Eric