bug#46001: asyncs.test intermittently fails in "preemption via sigprof"

[Rob Browning]

When 3.0.5 was uploaded to the Debian buildds, the amd64 build failed
like this:

  ERROR: asyncs.test: preemption via sigprof - arguments:
  ((wrong-type-arg #f "Wrong type (expecting ~A): ~S" ("resumable
  continuation" #<vm-continuation 7faf49c99350>) (#<vm-continuation
  7faf49c99350>)))

For example:

  
https://buildd.debian.org/status/fetch.php?pkg=guile-3.0&arch=amd64&ver=3.0.5-1&stamp=1610521112&raw=0

It was easy to reproduce locally on a Debian bullseye system (also
amd64, though of course the architecture might not be relevant):

  (while ./check-guile asyncs.test; do sleep 0.1; done)

This would reliably fail with the same error after a handful of
attempts.

-- 
Rob Browning
rlb @defaultvalue.org and @debian.org
GPG as of 2011-07-10 E6A9 DA3C C9FD 1FF8 C676 D2C4 C0F0 39E9 ED1B 597A
GPG as of 2002-11-03 14DD 432F AE39 534D B592 F9A0 25C8 D377 8C7E 73A4