On Tue, Sep 8, 2015 at 11:45 AM, Andrew Haley <aph@xxxxxxxxxx> wrote: > On 09/08/2015 10:15 AM, Mathieu Malaterre wrote: >> What is even more surprising is that I can no longer reproduce the >> behavior using `valgrind` from my 32bits chroot. >> >> I understand that my bug description is relatively small, but I am >> eager to report a more specific gcc issue. If anyone could help me >> narrow down this issue, I'd appreciate your comments. >> >> Please note that that I disabled any kind of optimizations by using >> (explicitly!) -O0. > > I'm guessing that it's some silliness with the FPU, but that's a wild > guess. Technically this code path is *not* using floating point at all (by JPEG 2000 reversible kernel design). integer based shift&additions operations only. > You first need to find out what part of the file is different, and > narrow it down from there. One question: how well do you understand > the OpenJPEG code base? Let me answer it this way: this is a huge task -for me- to narrow down this issue to a minimal C code.
