m68k/cc issue (was Re: gettimeofday seconds rollover problem?)

Till Straumann strauman at slac.stanford.edu
Mon Feb 27 21:03:02 UTC 2006


Someone (don't have enough m68k knowledge in my cache
behind my eyes) should be answer this. It's not
rocket science:

Do the enable/disable inlines potentially modify
a bit in the 'cc' that the ABI declares non-volatile?

BTW: I couldn't help playing with this and it seems
that 'cc' is ignored anyways on m68k and on powerpc
(I know that on the powerpc you must explicitely
list the non-volatile crX in the clobber list if you
modify them from an asm, 'cc' is definitely ignored)

void blah()
{
asm volatile("":::"cc");
}


is compiled (m68k-rtems-gcc -m528x, version 4.0.2) into

Disassembly of section .text:

00000000 <blah>:
    0:   4e75            rts



FWIW

-- T.




More information about the users mailing list