Livelock

Solution:
- Fix the race with a barrier before the single. This may fix the MATCH operation and fix the livelock error.
- Decide on a maximum number of iterations, and use a loop with that number rather than an infinite loop.

C$OMP PARALLEL PRIVATE (ID)

ID = OMP_GET_THREAD_NUM()

N = OMP_GET_NUM_THREADS()

1000 CONTINUE

PHASES[ID] = UPDATE(U, ID)

C$OMP BARRIER

C$OMP SINGLE

RES = MATCH (PHASES, N)

ICOUNT = ICOUNT + 1

C$OMP END SINGLE

IF (RES*RES .LT. TOL) GO TO 2000

IF (ICOUNT .GT. MAX) GO TO 2000

GO TO 1000

2000 CONTINUE

C$OMP END PARALLEL

Solution: