Currently the debug call protocol implementation we use for testing is
riddled with write barriers, and called from a signal handler. This is
not safe, as write barriers need a P to execute.
Ideally this implementation would be rewritten to avoid the write
barriers, but it's not straightforward, and needs some thought. As a
temporary measure, disable GC during the debug call tests to avoid a
write barrier.
Note that this does not indicate a problem with real use of the debug
call protocol. Only our test implementation has this issue, because it
needs to get executed in a signal handler, normally a separate process
is interfacing with the protocol via process signals and ptrace (and the
like).
Fixes #49370.
Change-Id: Ic0fde5d0f4c64f9ecc9789b7dabb3954538fe0a8
Reviewed-on: https://go-review.googlesource.com/c/go/+/361896
Trust: Michael Knyszek <mknyszek@google.com>
Run-TryBot: Michael Knyszek <mknyszek@google.com>
TryBot-Result: Go Bot <gobot@golang.org> Reviewed-by: Michael Pratt <mpratt@google.com>