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3 commits

Author SHA1 Message Date
Keith Randall
03ed43988f cmd/compile: allow multi-field structs to be stored directly in interfaces
If the struct is a bunch of 0-sized fields and one pointer field.

Merged revert-of-revert for 4 CLs.

original  revert
681937    695016
693415    694996
693615    695015
694195    694995

Fixes #74092
Update #74888
Update #74908
Update #74935
(updated issues are bugs in the last attempt at this)

Change-Id: I32246d49b8bac3bb080972dc06ab432a5480d560
Reviewed-on: https://go-review.googlesource.com/c/go/+/714421
Auto-Submit: Keith Randall <khr@golang.org>
Reviewed-by: David Chase <drchase@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Keith Randall <khr@google.com>
2025-11-14 12:37:44 -08:00
Keith Randall
caf9fc3ccd Revert "reflect: handle zero-sized fields of directly-stored structures correctly"
This reverts commit b3388569a1 (CL 694195)

Reason for revert: still causing compiler failures on Google test code

Change-Id: I2a9b0f9a57fe2b6977238bbfbefb572545210b9f
Reviewed-on: https://go-review.googlesource.com/c/go/+/694995
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Keith Randall <khr@google.com>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
Reviewed-by: Dmitri Shuralyov <dmitshur@golang.org>
2025-08-11 22:36:13 -07:00
Keith Randall
b3388569a1 reflect: handle zero-sized fields of directly-stored structures correctly
type W struct {
	E struct{}
	X *byte
}

type W is a "direct" type. That is, it is a pointer-ish type that can
be stored directly as the second word of an interface.

But if we ask reflect for W's first field, that value must *not* be
direct, as zero-sized things cannot be stored directly.

This was a problem introduced in CL 681937. Before that, types like W
were not eligible for directness.

Fixes #74935

Change-Id: Idefb55c23eaa59153009f863bad611593981e5cb
Reviewed-on: https://go-review.googlesource.com/c/go/+/694195
Auto-Submit: Keith Randall <khr@golang.org>
Reviewed-by: Keith Randall <khr@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Cuong Manh Le <cuong.manhle.vn@gmail.com>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
2025-08-08 06:51:37 -07:00