cmd/gb: wire up -race flag

cmd/gb/build.go

@@ -30,6 +30,9 @@ var (
 	// skip caching of packages
 	FF bool
 
+	// enable race runtime
+	race bool
+
 	ldflags, gcflags []string
 
 	P int // number of executors to run in parallel
@@ -45,6 +48,7 @@ func addBuildFlags(fs *flag.FlagSet) {
 	fs.BoolVar(&R, "r", false, "perform a release build")
 	fs.BoolVar(&F, "f", false, "rebuild up-to-date packages")
 	fs.BoolVar(&FF, "F", false, "do not cache built packages")
+	fs.BoolVar(&race, "race", false, "enable race detector")
 	fs.IntVar(&P, "P", runtime.NumCPU(), "number of parallel jobs")
 	fs.Var((*stringsFlag)(&ldflags), "ldflags", "flags passed to the linker")
 	fs.Var((*stringsFlag)(&gcflags), "gcflags", "flags passed to the compiler")

cmd/gb/gb_test.go

@@ -1223,3 +1223,46 @@ func TestA(t *testing.T) {
 	gb.run("test")
 	gb.grepStdout("^a$", "expected 'a'")
 }
+
+// test -race flag is wired up correctly
+func TestBuildRaceFlag(t *testing.T) {
+	gb := T{T: t}
+	defer gb.cleanup()
+
+	gb.tempDir("src/x")
+	gb.tempFile("src/x/x_race.go", "package x\nconst A = 1\n")
+	gb.tempFile("src/x/y.go", "// +build race\n\npackage x\nconst B = 2\n")
+	gb.tempFile("src/x/z.go", "package x\n const C = A +B\n")
+	gb.cd(gb.tempdir)
+	tmpdir := gb.tempDir("tmp")
+	gb.setenv("TMP", tmpdir)
+	gb.run("build", "-race", "x")
+	gb.mustBeEmpty(tmpdir)
+	gb.wantArchive(filepath.Join(gb.tempdir, "pkg", runtime.GOOS+"-"+runtime.GOARCH+"-race", "x.a"))
+}
+
+func TestTestRaceFlag(t *testing.T) {
+	gb := T{T: t}
+	defer gb.cleanup()
+
+	gb.tempDir("src/x")
+	gb.tempFile("src/x/x_race.go", "package x\nconst A = 1\n")
+	gb.tempFile("src/x/y.go", "// +build race\n\npackage x\nconst B = 2\n")
+	gb.tempFile("src/x/q.go", "// +build !race\n\npackage x\nconst B = 7\n")
+	gb.tempFile("src/x/x_test.go", `package x
+import "testing"
+
+func TestRaceFlag(t *testing.T) {
+	if A != 1 || B != 2 {
+		t.Fatal("expected", 1, 2,"got", A, B)
+	}
+}
+`)
+	gb.cd(gb.tempdir)
+	tmpdir := gb.tempDir("tmp")
+	gb.setenv("TMP", tmpdir)
+	gb.run("test", "-race", "x")
+	gb.grepStdout("^x$", "expected x") // output from gb test
+	gb.mustBeEmpty(tmpdir)
+	gb.mustNotExist(filepath.Join(gb.tempdir, "pkg")) // ensure no pkg directory is created
+}

cmd/gb/main.go

@@ -111,6 +111,9 @@ func main() {
 	}
 
 	args = fs.Args() // reset args to the leftovers from fs.Parse
+
+	debug.Debugf("args: %v", args)
+
 	if command == commands["plugin"] {
 		args = append([]string{name}, args...)
 	}
@@ -125,7 +128,14 @@ func main() {
 		gb.Gcflags(gcflags...),
 		gb.Ldflags(ldflags...),
 		gb.Tags(buildtags...),
+		func(c *gb.Context) error {
+			if race {
+				return gb.WithRace(c)
+			}
+			return nil
+		},
 	)
+
 	if err != nil {
 		fatalf("unable to construct context: %v", err)
 	}

cmd/gb/testflag.go

@@ -32,6 +32,7 @@ var testFlagDefn = map[string]*testFlagSpec{
 	"gcflags":   {},
 	"dotfile":   {},
 	"tags":      {},
+	"race":      {},
 
 	// Passed to the test binary
 	"q":                {boolVar: true, passToTest: true},

cmd/gb/testflag_test.go

@@ -118,6 +118,10 @@ func TestTestFlagsPreParse(t *testing.T) {
 			args:  []string{"-cover", "-name=jardin"},
 			pargs: []string{"-cover"},
 			eargs: []string{"-name=jardin"},
+		}, {
+			args:  []string{"-race", "-name=jardin"},
+			pargs: []string{"-race"},
+			eargs: []string{"-name=jardin"},
 		}}
 
 	for _, tt := range tests {