fb5e5cbdd4
Spotted while running the tests on MIPS, where sigset_t is actually large enough. The bits in sigset_t are used such that signal 1 is represented by bit 0, so the range of signals is actually [1, 8*sizeof(sigset_t)]; it seems clearer to reword the code in terms of valid bit offsets [0, 8*sizeof(sigset_t)), which leads to the usual bounds checking idiom. Change-Id: Id899c288e15ff71c85dd2fd33c47f8e97aa1956f