diff options
| -rw-r--r-- | src/cmd/compile/internal/walk/complit.go | 8 | ||||
| -rw-r--r-- | test/fixedbugs/issue52953.go | 29 |
2 files changed, 36 insertions, 1 deletions
diff --git a/src/cmd/compile/internal/walk/complit.go b/src/cmd/compile/internal/walk/complit.go index abd920d6461..1f288d21c18 100644 --- a/src/cmd/compile/internal/walk/complit.go +++ b/src/cmd/compile/internal/walk/complit.go @@ -621,6 +621,12 @@ func oaslit(n *ir.AssignStmt, init *ir.Nodes) bool { // not a special composite literal assignment return false } + if x.Addrtaken() { + // If x is address-taken, the RHS may (implicitly) uses LHS. + // Not safe to do a special composite literal assignment + // (which may expand to multiple assignments). + return false + } switch n.Y.Op() { default: @@ -629,7 +635,7 @@ func oaslit(n *ir.AssignStmt, init *ir.Nodes) bool { case ir.OSTRUCTLIT, ir.OARRAYLIT, ir.OSLICELIT, ir.OMAPLIT: if ir.Any(n.Y, func(y ir.Node) bool { return ir.Uses(y, x) }) { - // not a special composite literal assignment + // not safe to do a special composite literal assignment if RHS uses LHS. return false } anylit(n.Y, n.X, init) diff --git a/test/fixedbugs/issue52953.go b/test/fixedbugs/issue52953.go new file mode 100644 index 00000000000..2085e4e3fe3 --- /dev/null +++ b/test/fixedbugs/issue52953.go @@ -0,0 +1,29 @@ +// run + +// Copyright 2022 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. + +// Issue 52953: miscompilation for composite literal assignment +// when LHS is address-taken. + +package main + +type T struct { + Field1 bool +} + +func main() { + var ret T + ret.Field1 = true + var v *bool = &ret.Field1 + ret = T{Field1: *v} + check(ret.Field1) +} + +//go:noinline +func check(b bool) { + if !b { + panic("FAIL") + } +} |