diff options
| author | Matthew Dempsky <mdempsky@google.com> | 2021-06-25 11:07:28 -0700 |
|---|---|---|
| committer | Matthew Dempsky <mdempsky@google.com> | 2021-06-28 23:31:13 +0000 |
| commit | 4bb0847b088eb3eb6122a18a87e1ca7756281dcc (patch) | |
| tree | 9baa7b329f0ec4cfdc2f80a833e14070794fe76c /test | |
| parent | 1519271a939ad27da133318dc4bde7e6a41a35b5 (diff) | |
| download | go-4bb0847b088eb3eb6122a18a87e1ca7756281dcc.tar.gz go-4bb0847b088eb3eb6122a18a87e1ca7756281dcc.zip | |
cmd/compile,runtime: change unsafe.Slice((*T)(nil), 0) to return []T(nil)
This CL removes the unconditional OCHECKNIL check added in
walkUnsafeSlice by instead passing it as a pointer to
runtime.unsafeslice, and hiding the check behind a `len == 0` check.
While here, this CL also implements checkptr functionality for
unsafe.Slice and disallows use of unsafe.Slice with //go:notinheap
types.
Updates #46742.
Change-Id: I743a445ac124304a4d7322a7fe089c4a21b9a655
Reviewed-on: https://go-review.googlesource.com/c/go/+/331070
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Trust: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Keith Randall <khr@golang.org>
Diffstat (limited to 'test')
| -rw-r--r-- | test/unsafebuiltins.go | 7 |
1 files changed, 5 insertions, 2 deletions
diff --git a/test/unsafebuiltins.go b/test/unsafebuiltins.go index c10f8084a7..4c940aa855 100644 --- a/test/unsafebuiltins.go +++ b/test/unsafebuiltins.go @@ -30,8 +30,11 @@ func main() { assert(len(s) == len(p)) assert(cap(s) == len(p)) - // nil pointer - mustPanic(func() { _ = unsafe.Slice((*int)(nil), 0) }) + // nil pointer with zero length returns nil + assert(unsafe.Slice((*int)(nil), 0) == nil) + + // nil pointer with positive length panics + mustPanic(func() { _ = unsafe.Slice((*int)(nil), 1) }) // negative length var neg int = -1 |