[release-branch.go1.13] reflect: zero stack slots before writing to them with write barriers
reflect.assignTo writes to the target using write barriers. Make sure
that the memory it is writing to is zeroed, so the write barrier does
not read pointers from uninitialized memory.
Fixes #39697
Change-Id: Ia64b2cacc193bffd0c1396bbce1dfb8182d4905b
Reviewed-on: https://go-review.googlesource.com/c/go/+/238760
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
(cherry picked from commit
3dec253783e1211989102ac6abd34cddbf8ba0e6)
Reviewed-on: https://go-review.googlesource.com/c/go/+/238862
Reviewed-by: Emmanuel Odeke <emm.odeke@gmail.com>