overflow / underflow problem in objectheader

[emeryberger]

Reproducible error:

Switching the order of _magic with _size in include/objectheader.h causes a failure when running examples/falsesharing:

Current order:

Starting threads. theItem is at 0x8049e34 Done. Sheriff-Detect: false sharing detected. Object 1: cache interleaving writes 430 (25 per cache line, 430 times on 1 actual line(s), object writes = 435) Object start = a8591020; length = 1024. Heap object accumulated by 1, unit length = 1024, total length = 1024, cache lines = 16. Object allocation call site information: Call site 0 8048916: /media/psf/Home/git/sheriff/examples/falsesharing.cpp:40 Call site 1 804882c: ??:0

Switched order:

Starting threads. theItem is at 0x8049e34 Done. Sanity check failed in process 13808. Current _magic 8048916 at 0xa8621018 Aborted