On Thu, May 17, 2012 at 03:21:12PM +0100, Luis Alves wrote: > Hi Greg, > > Yes, that file exists in the sources gcc-<version>/gcc/config/m68k/uclinux.h > I've changed those flags and it works (at least in a small test with > the first pass gcc). > > But take a look at the comments in my bug report: > http://gcc.gnu.org/bugzilla/show_bug.cgi?id=53386 > > Someone says that it is related to the ABI change in gcc >= 4.3.x and > that I should use as target 'm68k-uclinuxoldabi' and > --with-cpu=m68000. > > For now I've just changed the flags in the header file... maybe I'll > try building it with that weird target (m68k-uclinuxoldabi).
gcc 4.3 at least change the size of floating point from 80 to 64bit on coldfire (and possibly on m68k in general, not sure), and also made some changes in other things. gcc 4.2 would fail to compile some programs for me, running out of space in the offset table as far as I can tell, while gcc 4.3 has never had any problems with that. My understanding is that gcc 4.3 switched to a different way of handling the GOT which works much better, but is almost certainly incompatible with the old method. gcc 4.3 also optimizes a lot more in m68k than 4.2 (I had to insert memory barriers in uboot to convince gcc 4.3 not to rearrange seemingly unrelated memory read and writes in the memory controller setup, where as gcc 4.2 did so little optimization that it never had any issue). gcc 4.3 didn't do anything wrong, the code simply wasn't specific enough about what it wanted. So I like the gcc 4.3 improvements over 4.2. -- Len Sorensen _______________________________________________ uClinux-dev mailing list uClinux-dev@uclinux.org http://mailman.uclinux.org/mailman/listinfo/uclinux-dev This message was resent by uclinux-dev@uclinux.org To unsubscribe see: http://mailman.uclinux.org/mailman/options/uclinux-dev
