Sunday, March 14, 2004

driver crashes fixed! After much hair-pulling and teeth-gnashing, I narrowed down the cause of the kernel panics on OpenDarwin 6.6.2. If the driver was compiled with optimization flag -O3 then it would panic every time. If I changed the optimization to -O0, no crashes. Copying over a set of x86 binaries that had been compiled on darwin 7.x and running them on OD 6.x also worked fine. This points squarely at a bug in gcc that shipped with OD 6.x. It must be reordering some instructions that result in a null pointer being evaluated (or some other similar problem). I'll see if I can't narrow it down to a single line of offending code and fix it programatically. If that doesn't work, then I'll just add a note to the README specifying this problem and its workaround. 9:00:42 AM    comment []