Re: [avr-gcc-list] GCC Functions

[Joerg Wunsch]

Patrick Lanphier <address@hidden> wrote:

> ..., I don't know why but the last two lines work and the
> first three do not when compiling for the chip?
> 
> #avr-gcc -O0 -Wall -mmcu=at90s2313 -c demo2c.c -o demo1.o
> #avr-gcc -o demo1.elf demo1.o
> #avr-objcopy -O ihex demo1.elf demo1.hex
> 
> avr-gcc -O0 -mmcu=at90s2313 -Wall -o demo1 demo2c.c
> avr-objcopy -O ihex demo1 demo1.hex

Both versions are supposed to work identically (with the exception
that the second one doesn't store demo1.o permanently, of course).  If
one works and the other doesn't, i suppose your gcc installation is
broken.  You could do two things to analyze the situation:

.. disassemble both resulting ELF files (demo1.elf / demo1), and
  compare the result; maybe even running avr-nm on them already
  would make the difference obvious

.. include -v to all compiler command lines; this will show you
  the command-line calls to the backend tools avr-gcc is issuing;
  somehow, they must be different between both versions

-- 
J"org Wunsch                                           Unix support engineer
address@hidden        http://www.interface-systems.de/~j/