This test case is consistently failing on my machine when building guile:

./pre-inst-env guix build guile

...
Running suspendable-ports.test
UNRESOLVED: suspendable-ports.test: non-revealed port is closed
ERROR: suspendable-ports.test: revealed port fdes not closed -
arguments: ((system-error "seek" "~A" ("Bad file descriptor") (9)))

Totals for this test run:
passes:                 42439
failures:               0
unexpected passes:      0
expected failures:      10
unresolved test cases:  554
untested test cases:    1
unsupported test cases: 1
errors:                 1

Kernel: Linux bb11 5.14.3 #1 SMP 1 x86_64 GNU/Linux

Guix commit: c4b7bcc2569e40c6b925bc9e8fde01c5744c29f7

Log file attached.

--
Sincerely,
Ryan Sundberg