From 644543dd6447b39800825f66411df06066baa84e Mon Sep 17 00:00:00 2001 From: LE Manh Cuong Date: Tue, 16 Apr 2019 20:32:31 +0700 Subject: [PATCH] cmd/compile: fix const declaration group broken with closure In typecheckclosure, a xfunc node will be put to xtop. But that node can be shared between multiple closures, like in a const declaration group: const ( x = unsafe.Sizeof(func() {}) y ) It makes a xfunc node appears multiple times in xtop, causing duplicate initLSym run. To fix this issue, we only do typecheck for xfunc one time, and setup closure node earlier in typecheckclosure process. Fixes #30709 Change-Id: Ic924a157ee9f3e5d776214bef5390849ddc8aab9 Reviewed-on: https://go-review.googlesource.com/c/go/+/172298 Reviewed-by: Matthew Dempsky Run-TryBot: Matthew Dempsky TryBot-Result: Gobot Gobot --- src/cmd/compile/internal/gc/closure.go | 14 +++++++---- test/fixedbugs/issue30709.go | 33 ++++++++++++++++++++++++++ test/fixedbugs/issue30709.out | 4 ++++ 3 files changed, 47 insertions(+), 4 deletions(-) create mode 100644 test/fixedbugs/issue30709.go create mode 100644 test/fixedbugs/issue30709.out diff --git a/src/cmd/compile/internal/gc/closure.go b/src/cmd/compile/internal/gc/closure.go index 6db0f02001..89e2a4ef00 100644 --- a/src/cmd/compile/internal/gc/closure.go +++ b/src/cmd/compile/internal/gc/closure.go @@ -73,6 +73,16 @@ func (p *noder) funcLit(expr *syntax.FuncLit) *Node { func typecheckclosure(clo *Node, top int) { xfunc := clo.Func.Closure + clo.Func.Ntype = typecheck(clo.Func.Ntype, Etype) + clo.Type = clo.Func.Ntype.Type + clo.Func.Top = top + + // Do not typecheck xfunc twice, otherwise, we will end up pushing + // xfunc to xtop multiple times, causing initLSym called twice. + // See #30709 + if xfunc.Typecheck() == 1 { + return + } for _, ln := range xfunc.Func.Cvars.Slice() { n := ln.Name.Defn @@ -95,10 +105,6 @@ func typecheckclosure(clo *Node, top int) { declare(xfunc.Func.Nname, PFUNC) xfunc = typecheck(xfunc, ctxStmt) - clo.Func.Ntype = typecheck(clo.Func.Ntype, Etype) - clo.Type = clo.Func.Ntype.Type - clo.Func.Top = top - // Type check the body now, but only if we're inside a function. // At top level (in a variable initialization: curfn==nil) we're not // ready to type check code yet; we'll check it later, because the diff --git a/test/fixedbugs/issue30709.go b/test/fixedbugs/issue30709.go new file mode 100644 index 0000000000..49524540ed --- /dev/null +++ b/test/fixedbugs/issue30709.go @@ -0,0 +1,33 @@ +// run + +// Copyright 2019 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. + +// Check closure in const declaration group can be compiled +// and set correct value + +package main + +import "unsafe" + +const ( + x = unsafe.Sizeof(func() {}) + y +) + +func main() { + const ( + z = unsafe.Sizeof(func() {}) + t + ) + + // x and y must be equal + println(x == y) + // size must be greater than zero + println(y > 0) + + // Same logic as x, y above + println(z == t) + println(t > 0) +} diff --git a/test/fixedbugs/issue30709.out b/test/fixedbugs/issue30709.out new file mode 100644 index 0000000000..1140ff52e2 --- /dev/null +++ b/test/fixedbugs/issue30709.out @@ -0,0 +1,4 @@ +true +true +true +true -- 2.48.1