From d5aa088d822bc8ef3ceb80c20184f40fcb9b8d2e Mon Sep 17 00:00:00 2001 From: "Bryan C. Mills" Date: Wed, 24 Aug 2022 09:45:18 -0400 Subject: [PATCH] cmd/go: avoid registering AtExit handlers in tests Ever since 'go build' was added (in CL 5483069), it has used an atexit handler to clean up working directories. CL 154109 introduced 'cc' command to the script test framework that called Init on a builder once per invocation. Unfortunately, since base.AtExit is unsynchronized, the Init added there caused any script that invokes that command to be unsafe for concurrent use. This change fixes the race by having the 'cc' command pass in its working directory instead of allowing the Builder to allocate one. Following modern Go best practices, it also replaces the in-place Init method (which is prone to typestate and aliasing bugs) with a NewBuilder constructor function. Fixes #54423. Change-Id: I8fc2127a7d877bb39a1174e398736bb51d03d4d2 Reviewed-on: https://go-review.googlesource.com/c/go/+/425205 TryBot-Result: Gopher Robot Run-TryBot: Bryan Mills Auto-Submit: Bryan Mills Reviewed-by: Than McIntosh --- src/cmd/go/internal/envcmd/env.go | 4 ++-- src/cmd/go/internal/list/list.go | 3 +-- src/cmd/go/internal/run/run.go | 3 +-- src/cmd/go/internal/test/test.go | 16 ++++++++++++---- src/cmd/go/internal/vet/vet.go | 3 +-- src/cmd/go/internal/work/action.go | 14 ++++++++++++-- src/cmd/go/internal/work/build.go | 7 +++---- src/cmd/go/script_test.go | 4 +--- 8 files changed, 33 insertions(+), 21 deletions(-) diff --git a/src/cmd/go/internal/envcmd/env.go b/src/cmd/go/internal/envcmd/env.go index 012ea4abaf..bbd3318d26 100644 --- a/src/cmd/go/internal/envcmd/env.go +++ b/src/cmd/go/internal/envcmd/env.go @@ -174,8 +174,8 @@ func ExtraEnvVars() []cfg.EnvVar { // ExtraEnvVarsCostly returns environment variables that should not leak into child processes // but are costly to evaluate. func ExtraEnvVarsCostly() []cfg.EnvVar { - var b work.Builder - b.Init() + b := work.NewBuilder("") + cppflags, cflags, cxxflags, fflags, ldflags, err := b.CFlags(&load.Package{}) if err != nil { // Should not happen - b.CFlags was given an empty package. diff --git a/src/cmd/go/internal/list/list.go b/src/cmd/go/internal/list/list.go index 2e3614d317..0b928d27e6 100644 --- a/src/cmd/go/internal/list/list.go +++ b/src/cmd/go/internal/list/list.go @@ -689,8 +689,7 @@ func runList(ctx context.Context, cmd *base.Command, args []string) { // Do we need to run a build to gather information? needStale := (listJson && listJsonFields.needAny("Stale", "StaleReason")) || strings.Contains(*listFmt, ".Stale") if needStale || *listExport || *listCompiled { - var b work.Builder - b.Init() + b := work.NewBuilder("") b.IsCmdList = true b.NeedExport = *listExport b.NeedCompiledGoFiles = *listCompiled diff --git a/src/cmd/go/internal/run/run.go b/src/cmd/go/internal/run/run.go index ebe1611819..6b253a2c9e 100644 --- a/src/cmd/go/internal/run/run.go +++ b/src/cmd/go/internal/run/run.go @@ -91,8 +91,7 @@ func runRun(ctx context.Context, cmd *base.Command, args []string) { } work.BuildInit() - var b work.Builder - b.Init() + b := work.NewBuilder("") b.Print = printStderr i := 0 diff --git a/src/cmd/go/internal/test/test.go b/src/cmd/go/internal/test/test.go index aa5e41e004..028db84cc4 100644 --- a/src/cmd/go/internal/test/test.go +++ b/src/cmd/go/internal/test/test.go @@ -744,8 +744,7 @@ func runTest(ctx context.Context, cmd *base.Command, args []string) { } } - var b work.Builder - b.Init() + b := work.NewBuilder("") if cfg.BuildI { fmt.Fprint(os.Stderr, "go: -i flag is deprecated\n") @@ -800,7 +799,16 @@ func runTest(ctx context.Context, cmd *base.Command, args []string) { if !testC || a.Failed { return } - b.Init() + + // TODO(bcmills): I have no idea why the Builder must be reset here, but + // without this reset dance, TestGoTestDashIDashOWritesBinary fails with + // lots of "vet config not found" errors. This was added in CL 5699088, + // which had almost no public discussion, a very short commit description, + // and left no comment in the code to explain what is going on here. 🤯 + // + // Maybe this has the effect of removing actions that were registered by the + // call to CompileAction above? + b = work.NewBuilder("") } var builds, runs, prints []*work.Action @@ -916,7 +924,7 @@ func runTest(ctx context.Context, cmd *base.Command, args []string) { ensureImport(p, "sync/atomic") } - buildTest, runTest, printTest, err := builderTest(&b, ctx, pkgOpts, p, allImports[p]) + buildTest, runTest, printTest, err := builderTest(b, ctx, pkgOpts, p, allImports[p]) if err != nil { str := err.Error() str = strings.TrimPrefix(str, "\n") diff --git a/src/cmd/go/internal/vet/vet.go b/src/cmd/go/internal/vet/vet.go index a0b11fdd3d..085c7d23b2 100644 --- a/src/cmd/go/internal/vet/vet.go +++ b/src/cmd/go/internal/vet/vet.go @@ -94,8 +94,7 @@ func runVet(ctx context.Context, cmd *base.Command, args []string) { base.Fatalf("no packages to vet") } - var b work.Builder - b.Init() + b := work.NewBuilder("") root := &work.Action{Mode: "go vet"} for _, p := range pkgs { diff --git a/src/cmd/go/internal/work/action.go b/src/cmd/go/internal/work/action.go index c0862c5efe..4bbd23ab8e 100644 --- a/src/cmd/go/internal/work/action.go +++ b/src/cmd/go/internal/work/action.go @@ -240,7 +240,13 @@ const ( ModeVetOnly = 1 << 8 ) -func (b *Builder) Init() { +// NewBuilder returns a new Builder ready for use. +// +// If workDir is the empty string, NewBuilder creates a WorkDir if needed +// and arranges for it to be removed in case of an unclean exit. +func NewBuilder(workDir string) *Builder { + b := new(Builder) + b.Print = func(a ...any) (int, error) { return fmt.Fprint(os.Stderr, a...) } @@ -249,7 +255,9 @@ func (b *Builder) Init() { b.toolIDCache = make(map[string]string) b.buildIDCache = make(map[string]string) - if cfg.BuildN { + if workDir != "" { + b.WorkDir = workDir + } else if cfg.BuildN { b.WorkDir = "$WORK" } else { tmp, err := os.MkdirTemp(cfg.Getenv("GOTMPDIR"), "go-build") @@ -306,6 +314,8 @@ func (b *Builder) Init() { base.Exit() } } + + return b } func CheckGOOSARCHPair(goos, goarch string) error { diff --git a/src/cmd/go/internal/work/build.go b/src/cmd/go/internal/work/build.go index 352e46b48f..e34cacca03 100644 --- a/src/cmd/go/internal/work/build.go +++ b/src/cmd/go/internal/work/build.go @@ -403,8 +403,7 @@ var RuntimeVersion = runtime.Version() func runBuild(ctx context.Context, cmd *base.Command, args []string) { modload.InitWorkfile() BuildInit() - var b Builder - b.Init() + b := NewBuilder("") pkgs := load.PackagesAndErrors(ctx, load.PackageOpts{AutoVCS: true}, args) load.CheckPackageErrors(pkgs) @@ -728,8 +727,8 @@ func InstallPackages(ctx context.Context, patterns []string, pkgs []*load.Packag } base.ExitIfErrors() - var b Builder - b.Init() + b := NewBuilder("") + depMode := ModeBuild if cfg.BuildI { depMode = ModeInstall diff --git a/src/cmd/go/script_test.go b/src/cmd/go/script_test.go index d497724331..ca76ab5ab8 100644 --- a/src/cmd/go/script_test.go +++ b/src/cmd/go/script_test.go @@ -576,10 +576,8 @@ func (ts *testScript) cmdCc(want simpleStatus, args []string) { ts.fatalf("usage: cc args... [&]") } - var b work.Builder - b.Init() + b := work.NewBuilder(ts.workdir) ts.cmdExec(want, append(b.GccCmd(".", ""), args...)) - robustio.RemoveAll(b.WorkDir) } // cd changes to a different directory. -- 2.48.1