From 973befe714d43ebb3f04a583cc136ffe8909b344 Mon Sep 17 00:00:00 2001 From: Cuong Manh Le Date: Sat, 30 Mar 2024 17:35:46 +0700 Subject: [PATCH] cmd/compile: check ODEREF for safe lhs in assignment during static init For #66585 Change-Id: Iddc407e3ef4c3b6ecf5173963b66b3e65e43c92d Reviewed-on: https://go-review.googlesource.com/c/go/+/575336 LUCI-TryBot-Result: Go LUCI Reviewed-by: Keith Randall Auto-Submit: Cuong Manh Le Reviewed-by: Keith Randall Reviewed-by: Dmitri Shuralyov --- src/cmd/compile/internal/staticinit/sched.go | 8 ++++++- test/codegen/issue66585.go | 24 ++++++++++++++++++++ 2 files changed, 31 insertions(+), 1 deletion(-) create mode 100644 test/codegen/issue66585.go diff --git a/src/cmd/compile/internal/staticinit/sched.go b/src/cmd/compile/internal/staticinit/sched.go index 4191f6997e..1f119920e9 100644 --- a/src/cmd/compile/internal/staticinit/sched.go +++ b/src/cmd/compile/internal/staticinit/sched.go @@ -881,7 +881,13 @@ func mayModifyPkgVar(n ir.Node) bool { // safeLHS reports whether the assigned-to variable lhs is either a // local variable or a global from another package. safeLHS := func(lhs ir.Node) bool { - v, ok := ir.OuterValue(lhs).(*ir.Name) + outer := ir.OuterValue(lhs) + // "*p = ..." should be safe if p is a local variable. + // TODO: Should ir.OuterValue handle this? + for outer.Op() == ir.ODEREF { + outer = outer.(*ir.StarExpr).X + } + v, ok := outer.(*ir.Name) return ok && v.Op() == ir.ONAME && !(v.Class == ir.PEXTERN && v.Sym().Pkg == types.LocalPkg) } diff --git a/test/codegen/issue66585.go b/test/codegen/issue66585.go new file mode 100644 index 0000000000..32a180be0e --- /dev/null +++ b/test/codegen/issue66585.go @@ -0,0 +1,24 @@ +// asmcheck + +// Copyright 2024 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 + +var x = func() int { + n := 0 + f(&n) + return n +}() + +func f(p *int) { + *p = 1 +} + +var y = 1 + +// z can be static initialized. +// +// amd64:-"MOVQ" +var z = y -- 2.48.1