race-until test runs forever (1.2.0 + affinity patch, NetBSD 9 amd64)

[gdt]

I'm building 1.2.0 plus the patch to not use affinity on most platforms (thanks @aconchillo), under pkgsrc.

The test that prints assert run-fibers on (race-until 100) terminates: runs indefinitely. I have done a build and make check 4 or 5 times and the indefinite running (with CPU usage - I can hear the fan spin up) happens reliably.

I'm sure there is a bug, maybe fibers, maybe guile, maybe in the OS, but I have no idea where. But, this issue is that the test should instead always exit, failing if that's how it is, perhaps just by having a max loop count.

The tests prior to this pass, with very reasonable runtimes, almost all less than 20 ms.

[gdt]

Actually some take longer but are clearly not stuck:

assert terminates: (run-fibers (lambda () (spawn-fiber-tree 5 (lambda () (sleep 1)))) #:drain? #t): ok (1.011651015 s)
assert terminates: (run-fibers (lambda () (spawn-fiber-chain 5)) #:drain? #t): ok (9.70913e-4 s)
assert terminates: (run-fibers (lambda () (spawn-fiber-chain 50)) #:drain? #t): ok (0.001394422 s)
assert terminates: (run-fibers (lambda () (spawn-fiber-chain 500)) #:drain? #t): ok (0.007145873 s)
assert terminates: (run-fibers (lambda () (spawn-fiber-chain 5000)) #:drain? #t): ok (0.05655267 s)
assert terminates: (run-fibers (lambda () (spawn-fiber-chain 50000)) #:drain? #t): ok (0.591639325 s)
assert terminates: (run-fibers (lambda () (spawn-fiber-chain 500000)) #:drain? #t): ok (5.526817611 s)
assert terminates: (run-fibers (lambda () (spawn-fiber-chain 5000000)) #:drain? #t): ok (55.836063731 s)
assert terminates: (run-fibers (lambda () (test-run-order 10)) #:parallelism 1 #:drain? #t): ok (0.038900581 s)
assert terminates: (run-fibers (lambda () (test-wakeup-order 10)) #:parallelism 1 #:drain? #t): ok (2.51773e-4 s)
assert terminates: (run-fibers (lambda () 1) #:drain? #t): ok (7.68028e-4 s)
assert run-fiber-return-vals equal to (1): ok
assert terminates: (run-fibers (lambda () (do-times 20 (check-sleep (random 1.0)))) #:drain? #t): assert sleep 0.06564007283307066s < actual 0.071227626s: #t (diff: 8.512411589089872%)