runtime: run TestSignalDuringExec in its own process group
TestSignalDuringExec sends a SIGWINCH to the whole process group.
However, it may execute concurrently with other copies of the runtime
tests, especially through `go tool dist`, and gdb version <12.1 has a
bug in non-interactive mode where recieving a SIGWINCH causes a crash.
This change modifies SignalDuringExec in the testprog to first fork
itself into a new process group. To avoid issues with Ctrl+C and the new
process group hanging, the new process blocks on a pipe that is passed
down to it. This pipe is automatically closed when its parent exits,
which should ensure that the subprocess also exits.
Fixes #58932.
Change-Id: I3906afa28cf8b15d22ae612d071bce7f30fc3e6c
Cq-Include-Trybots: luci.golang.try:gotip-linux-amd64-longtest-noswissmap,gotip-linux-amd64-longtest-aliastypeparams,gotip-linux-amd64-longtest,gotip-linux-386-longtest
Reviewed-on: https://go-review.googlesource.com/c/go/+/686875
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com> Reviewed-by: Michael Pratt <mpratt@google.com>