On Mon, 2016-08-01 at 22:41 +1000, oliver wrote: > On Mon, Aug 1, 2016 at 9:27 PM, Martin Liška <mliska@xxxxxxx> wrote: > > > > On 08/01/2016 01:09 PM, Michal Hocko wrote: > > > > > > [CC our gcc guy - I guess he has some theory for this] > > > > > > On Sun 31-07-16 14:11:25, Michal Hocko wrote: > > > > > > > > It seems that this has been already reported and Jason has noticed [1] that > > > > the problem is in the disabled optimizations: > > > > > > > > $ grep CRYPTO_DEV_UX500_DEBUG .config > > > > CONFIG_CRYPTO_DEV_UX500_DEBUG=y > > > > > > > > if I disable this particular option the code compiles just fine. I have > > > > no idea what is wrong about the code but it seems to depend on > > > > optimizations enabled which sounds a bit scrary... > > > > > > > > [1] http://www.spinics.net/lists/linux-mm/msg109590.html > > Hi. > > > > The difference is that w/o any optimization level, GCC doesn't make %c0 an > > intermediate integer operand [1] (see description of "i" constraint). > We recently hit a similar problem on ppc where the compiler couldn't > satisfy an "i" when it was wrapped in an function and optimisations > were disabled. The fix[1] was to change the function signature so that > it's arguments were explicitly const. I don't know enough about gcc to > tell if that behaviour is arch specific or not, but it's worth trying. > > Oliver > > [1] https://lists.ozlabs.org/pipermail/skiboot/2016-July/004061.html Yes, the way I solved the issue was to look at the RTL and provide hints to the compiler that the passed argument was a constant and it needed to be passed as such to the instruction I would suggest just looking at the RTL and figuring out why the constraints break Balbir Singh. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>