Re: [Flashforth-devel] building flashforth with avra?

[Christopher H. <chr...@li...>]

I believe that I should be able to figure out linker scripts, though in
the process I am getting stuck on another linker issue. I modified the
XC directive to a simple .section NRWW and tried avr-gcc --verbose
-mmcu=atmega328p -I. -D__ATmega328P__ -x assembler-with-cpp ff-
libre.asm, in hopes that verbose output would dump the exact location
of the default linker script, which I could use as a starting point.
(According to gcc docs there is always a default linker script if non
is specified.) Insteader linker dies with error
avr-ld: /home/christopher/.guix-
profile/avr/lib/avr5/crtatmega328p.o:(.init9+0x0): undefined reference
to `main'
I guess I need to figure out what to pass in to avr-gcc to fit the
FlashForth entry paradigm. I looked for some guidance from avr-libc-
users-manual, which has a lot of info on assembly and AVR, but the
paradigm there seems to expect that you have a .text section, a main(),
and maybe an .initN section.

On Tue, 2021-05-04 at 13:06 +0300, Mikael Nordman wrote:
> Hi Chris,
> Here is the link for the answer I got from Microchip. They modified
> the XC8 suite somehow. Maybe both AVR-AS and AVR-LD.
> https://www.microchip.com/forums/m1170217.aspx
> It is possible use a custom linker script instead, but I did not want
> to maintain linker files for FlashForth.
> If you come up with the linker scripts for the supported Atmegas, I
> can add them into  FlashForth.
> BR Mikael
> 
> 
> On 2021-05-04 09:01, Christopher Howard wrote:
> > That you for your help.
> >  
> > I'm no expert on the subject at this point, but it seems like there
> > must be some better way to do this than filling a ton of memory
> > each time I upload FlashForth to a chip. Seems like I should be
> > able to get something equivalent to .NRWW directive with some
> > combination of a named section and a section address in a linker
> > script.
> >  
> > I'm mildly curious what is really going on behind that XC8 .NRWW
> > "addition". Unless they've somehow crossed the assembler/linker
> > boundry, they must pass some extra information on to the linker...?
> > Something that gives instructions to their own linker script, or to
> > a modified Gnu LD?
> >  
> > Anyway, sounds like I've finally got an excuse now to become an
> > expert on linking.
> >  
-- 
Christopher Howard
blog: https://librehacker.com
social: https://gnusocial.club/librehacker