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| author | Francisco Ferraz <francisco3ferraz@gmail.com> | 2026-02-26 11:01:01 +0000 |
|---|---|---|
| committer | Gopher Robot <gobot@golang.org> | 2026-03-26 08:35:04 -0700 |
| commit | e27183eff891f052454f35f3c1029abf29c10e40 (patch) | |
| tree | ba3cbb5598bf6cd0b0ff21d4f9d939eb7f836f2f | |
| parent | 98d4c11d8f3d505556dc7ad128142f2b24e5911a (diff) | |
| download | go-e27183eff891f052454f35f3c1029abf29c10e40.tar.xz | |
[release-branch.go1.26] cmd/compile: fix internal compiler error: bad write barrier type
This change fixes an issue where the compiler panics with 'bad
write barrier type' for zero-sized arrays. The loops in
storeTypeScalars and storeTypePtrs erroneously processed
zero-sized arrays causing invalid operations. This ignores them.
Fixes #77809
Change-Id: I0db1b924fc63a75f1bed7488e2dc54d2de5dc0b2
Reviewed-on: https://go-review.googlesource.com/c/go/+/749380
Reviewed-by: Keith Randall <khr@google.com>
Auto-Submit: Keith Randall <khr@golang.org>
Reviewed-by: David Chase <drchase@google.com>
Reviewed-by: Keith Randall <khr@golang.org>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
(cherry picked from commit 244b156e67635f83a13b113c61f7729a79e06056)
Reviewed-on: https://go-review.googlesource.com/c/go/+/750823
Reviewed-by: Mark Freeman <markfreeman@google.com>
Auto-Submit: Dmitri Shuralyov <dmitshur@google.com>
Reviewed-by: Cherry Mui <cherryyz@google.com>
| -rw-r--r-- | src/cmd/compile/internal/ssagen/ssa.go | 4 | ||||
| -rw-r--r-- | test/fixedbugs/issue77815.go | 20 |
2 files changed, 22 insertions, 2 deletions
diff --git a/src/cmd/compile/internal/ssagen/ssa.go b/src/cmd/compile/internal/ssagen/ssa.go index 37a0cbd881..849781c9ee 100644 --- a/src/cmd/compile/internal/ssagen/ssa.go +++ b/src/cmd/compile/internal/ssagen/ssa.go @@ -5670,7 +5670,7 @@ func (s *state) storeTypeScalars(t *types.Type, left, right *ssa.Value, skip ski val := s.newValue1I(ssa.OpStructSelect, ft, int64(i), right) s.storeTypeScalars(ft, addr, val, 0) } - case t.IsArray() && t.NumElem() == 0: + case t.IsArray() && t.Size() == 0: // nothing case t.IsArray() && t.NumElem() == 1: s.storeTypeScalars(t.Elem(), left, s.newValue1I(ssa.OpArraySelect, t.Elem(), 0, right), 0) @@ -5710,7 +5710,7 @@ func (s *state) storeTypePtrs(t *types.Type, left, right *ssa.Value) { val := s.newValue1I(ssa.OpStructSelect, ft, int64(i), right) s.storeTypePtrs(ft, addr, val) } - case t.IsArray() && t.NumElem() == 0: + case t.IsArray() && t.Size() == 0: // nothing case t.IsArray() && t.NumElem() == 1: s.storeTypePtrs(t.Elem(), left, s.newValue1I(ssa.OpArraySelect, t.Elem(), 0, right)) diff --git a/test/fixedbugs/issue77815.go b/test/fixedbugs/issue77815.go new file mode 100644 index 0000000000..9adc108498 --- /dev/null +++ b/test/fixedbugs/issue77815.go @@ -0,0 +1,20 @@ +// compile + +// Copyright 2026 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package p + +type S struct { + a [4]struct{} + f chan int +} + +func f(p *S) { + var s S + + // Memory write that requires a write barrier should work + // with structs having zero-sized arrays of non-zero elements. + *p = s +} |