Riku Voipio wrote:
Do you know specifically how the debian buildds handle unaligned accesses? do they fix them up? do they generate a bus error? do they let them go silently wrong?Qemu allows unaligned memory accesses, which do not always work on real hardware, especially on armv5 and other older arms.
Regardless though I don't think that is the issue here as I've finally seen the einouterror in qemu after trying building in the precise path the buildd used (and I managed to reproduce it twice in a row under those circumstances). Unfortunately re-running the failing command manually succeeds so it seems like the long path alone is insufficiant to trigger the bug and there must be something in the environment the build system provides as well. I tried shoving a strace in there but that also seemed to stop it failing so i've no idea how I can track this down further.
Another complication is that this is happening as the first new compiler is being built using the compiler installed on the build system, in other words even if the issue is tracked down and fixed a new manual upload is likely to be needed to fix it.