am 5a6f593b: Merge "Use sigemptyset to initialise sigset_t values. sigset_t may not be implemented as an integral type."

* commit '5a6f593b6197b96f980d9d45f9a981ef8705caf4':
  Use sigemptyset to initialise sigset_t values. sigset_t may not be implemented as an integral type.