x/tools/cmd/signature-fuzzer/internal/fuzz-generator: unrecognized failures

[gopherbot]

#!watchflakes
default <- pkg == "golang.org/x/tools/cmd/signature-fuzzer/internal/fuzz-generator" && test == ""

Issue created automatically to collect these failures.

Example (log):

FAIL	golang.org/x/tools/cmd/signature-fuzzer/internal/fuzz-generator [build failed]
golang.org/x/tools/cmd/signature-fuzzer/internal/fuzz-generator: /home/swarming/.swarming/w/ir/x/w/goroot/pkg/tool/openbsd_ppc64/compile: fork/exec /home/swarming/.swarming/w/ir/x/w/goroot/pkg/tool/openbsd_ppc64/compile: resource temporarily unavailable

— watchflakes