[release-branch.go1.4] runtime: hashmap: move overflow pointer to end of bucket
Pointers to zero-sized values may end up pointing to the next
object in memory, and possibly off the end of a span. This
can cause memory leaks and/or confuse the garbage collector.
By putting the overflow pointer at the end of the bucket, we
make sure that pointers to any zero-sized keys or values don't
accidentally point to the next object in memory.
fixes #9384
Change-Id: I5d434df176984cb0210b4d0195dd106d6eb28f73
Reviewed-on: https://go-review.googlesource.com/1869
Reviewed-by: Russ Cox <rsc@golang.org>
(cherry picked from commit
fbc56cf05015899aba236d5a68096a770de3ad0a)
Reviewed-on: https://go-review.googlesource.com/2801
Reviewed-by: Andrew Gerrand <adg@golang.org>