This is the mail archive of the
gcc-patches@gcc.gnu.org
mailing list for the GCC project.
Re: -fstrict-volatile-bitfields fixes
On 12/05/2010 07:38 PM, Mark Mitchell wrote:
> On 12/2/2010 6:35 PM, DJ Delorie wrote:
>
>> I see no reason to flag RX or M32C with "abi_version_at_least(2)"
>> since those ports are newer than abi version 2.
>
> In that case, the solution for those ports is to refuse -fabi-version=2
> (or less); just issue an error message if that option is used.
>
>> For sh, not conforming to the volatile bitfields' mode causes a
>> hardware problem. If specifying the ABI changes the silicon to no
>> longer have this problem, I suppose we could check for it. Otherwise,
>> sh shouldn't check the ABI either.
>
> Similarly, here -- if the SH hardware can't work with the old ABI then
> we should probably just error out.
I don't think so. If a program requests the old ABI, and volatile
bitfields do not work with the old ABI, we can conclude that the program
does not use volatile bitfields.
In any case, I think the patch is a reasonable starting point, and
target maintainers can change behavior if they see fit. Ok to commit, or
what specific changes should I make?
Bernd