1 files changed, 286 insertions, 0 deletions
diff --git a/src/cmd/go/internal/work/init.go b/src/cmd/go/internal/work/init.go
new file mode 100644
index 0000000..ba7c7c2
--- /dev/null
+++ b/src/cmd/go/internal/work/init.go
@@ -0,0 +1,286 @@
+// Copyright 2017 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.
+
+// Build initialization (after flag parsing).
+
+package work
+
+import (
+	"cmd/go/internal/base"
+	"cmd/go/internal/cfg"
+	"cmd/go/internal/fsys"
+	"cmd/go/internal/modload"
+	"cmd/internal/objabi"
+	"cmd/internal/sys"
+	"flag"
+	"fmt"
+	"os"
+	"path/filepath"
+	"runtime"
+	"strings"
+)
+
+func BuildInit() {
+	modload.Init()
+	instrumentInit()
+	buildModeInit()
+	if err := fsys.Init(base.Cwd); err != nil {
+		base.Fatalf("go: %v", err)
+	}
+
+	// Make sure -pkgdir is absolute, because we run commands
+	// in different directories.
+	if cfg.BuildPkgdir != "" && !filepath.IsAbs(cfg.BuildPkgdir) {
+		p, err := filepath.Abs(cfg.BuildPkgdir)
+		if err != nil {
+			fmt.Fprintf(os.Stderr, "go %s: evaluating -pkgdir: %v\n", flag.Args()[0], err)
+			base.SetExitStatus(2)
+			base.Exit()
+		}
+		cfg.BuildPkgdir = p
+	}
+
+	// Make sure CC and CXX are absolute paths
+	for _, key := range []string{"CC", "CXX"} {
+		if path := cfg.Getenv(key); !filepath.IsAbs(path) && path != "" && path != filepath.Base(path) {
+			base.Fatalf("go %s: %s environment variable is relative; must be absolute path: %s\n", flag.Args()[0], key, path)
+		}
+	}
+
+	// For each experiment that has been enabled in the toolchain, define a
+	// build tag with the same name but prefixed by "goexperiment." which can be
+	// used for compiling alternative files for the experiment. This allows
+	// changes for the experiment, like extra struct fields in the runtime,
+	// without affecting the base non-experiment code at all. [2:] strips the
+	// leading "X:" from objabi.Expstring().
+	exp := objabi.Expstring()[2:]
+	if exp != "none" {
+		experiments := strings.Split(exp, ",")
+		for _, expt := range experiments {
+			cfg.BuildContext.BuildTags = append(cfg.BuildContext.BuildTags, "goexperiment."+expt)
+		}
+	}
+}
+
+func instrumentInit() {
+	if !cfg.BuildRace && !cfg.BuildMSan {
+		return
+	}
+	if cfg.BuildRace && cfg.BuildMSan {
+		fmt.Fprintf(os.Stderr, "go %s: may not use -race and -msan simultaneously\n", flag.Args()[0])
+		base.SetExitStatus(2)
+		base.Exit()
+	}
+	if cfg.BuildMSan && !sys.MSanSupported(cfg.Goos, cfg.Goarch) {
+		fmt.Fprintf(os.Stderr, "-msan is not supported on %s/%s\n", cfg.Goos, cfg.Goarch)
+		base.SetExitStatus(2)
+		base.Exit()
+	}
+	if cfg.BuildRace {
+		if !sys.RaceDetectorSupported(cfg.Goos, cfg.Goarch) {
+			fmt.Fprintf(os.Stderr, "go %s: -race is only supported on linux/amd64, linux/ppc64le, linux/arm64, freebsd/amd64, netbsd/amd64, darwin/amd64, darwin/arm64, and windows/amd64\n", flag.Args()[0])
+			base.SetExitStatus(2)
+			base.Exit()
+		}
+	}
+	mode := "race"
+	if cfg.BuildMSan {
+		mode = "msan"
+		// MSAN does not support non-PIE binaries on ARM64.
+		// See issue #33712 for details.
+		if cfg.Goos == "linux" && cfg.Goarch == "arm64" && cfg.BuildBuildmode == "default" {
+			cfg.BuildBuildmode = "pie"
+		}
+	}
+	modeFlag := "-" + mode
+
+	if !cfg.BuildContext.CgoEnabled {
+		if runtime.GOOS != cfg.Goos || runtime.GOARCH != cfg.Goarch {
+			fmt.Fprintf(os.Stderr, "go %s: %s requires cgo\n", flag.Args()[0], modeFlag)
+		} else {
+			fmt.Fprintf(os.Stderr, "go %s: %s requires cgo; enable cgo by setting CGO_ENABLED=1\n", flag.Args()[0], modeFlag)
+		}
+
+		base.SetExitStatus(2)
+		base.Exit()
+	}
+	forcedGcflags = append(forcedGcflags, modeFlag)
+	forcedLdflags = append(forcedLdflags, modeFlag)
+
+	if cfg.BuildContext.InstallSuffix != "" {
+		cfg.BuildContext.InstallSuffix += "_"
+	}
+	cfg.BuildContext.InstallSuffix += mode
+	cfg.BuildContext.BuildTags = append(cfg.BuildContext.BuildTags, mode)
+}
+
+func buildModeInit() {
+	gccgo := cfg.BuildToolchainName == "gccgo"
+	var codegenArg string
+
+	// Configure the build mode first, then verify that it is supported.
+	// That way, if the flag is completely bogus we will prefer to error out with
+	// "-buildmode=%s not supported" instead of naming the specific platform.
+
+	switch cfg.BuildBuildmode {
+	case "archive":
+		pkgsFilter = pkgsNotMain
+	case "c-archive":
+		pkgsFilter = oneMainPkg
+		if gccgo {
+			codegenArg = "-fPIC"
+		} else {
+			switch cfg.Goos {
+			case "darwin", "ios":
+				switch cfg.Goarch {
+				case "arm64":
+					codegenArg = "-shared"
+				}
+
+			case "dragonfly", "freebsd", "illumos", "linux", "netbsd", "openbsd", "solaris":
+				// Use -shared so that the result is
+				// suitable for inclusion in a PIE or
+				// shared library.
+				codegenArg = "-shared"
+			}
+		}
+		cfg.ExeSuffix = ".a"
+		ldBuildmode = "c-archive"
+	case "c-shared":
+		pkgsFilter = oneMainPkg
+		if gccgo {
+			codegenArg = "-fPIC"
+		} else {
+			switch cfg.Goos {
+			case "linux", "android", "freebsd":
+				codegenArg = "-shared"
+			case "windows":
+				// Do not add usual .exe suffix to the .dll file.
+				cfg.ExeSuffix = ""
+			}
+		}
+		ldBuildmode = "c-shared"
+	case "default":
+		switch cfg.Goos {
+		case "android":
+			codegenArg = "-shared"
+			ldBuildmode = "pie"
+		case "windows":
+			ldBuildmode = "pie"
+		case "ios":
+			codegenArg = "-shared"
+			ldBuildmode = "pie"
+		case "darwin":
+			switch cfg.Goarch {
+			case "arm64":
+				codegenArg = "-shared"
+			}
+			fallthrough
+		default:
+			ldBuildmode = "exe"
+		}
+		if gccgo {
+			codegenArg = ""
+		}
+	case "exe":
+		pkgsFilter = pkgsMain
+		ldBuildmode = "exe"
+		// Set the pkgsFilter to oneMainPkg if the user passed a specific binary output
+		// and is using buildmode=exe for a better error message.
+		// See issue #20017.
+		if cfg.BuildO != "" {
+			pkgsFilter = oneMainPkg
+		}
+	case "pie":
+		if cfg.BuildRace {
+			base.Fatalf("-buildmode=pie not supported when -race is enabled")
+		}
+		if gccgo {
+			codegenArg = "-fPIE"
+		} else {
+			switch cfg.Goos {
+			case "aix", "windows":
+			default:
+				codegenArg = "-shared"
+			}
+		}
+		ldBuildmode = "pie"
+	case "shared":
+		pkgsFilter = pkgsNotMain
+		if gccgo {
+			codegenArg = "-fPIC"
+		} else {
+			codegenArg = "-dynlink"
+		}
+		if cfg.BuildO != "" {
+			base.Fatalf("-buildmode=shared and -o not supported together")
+		}
+		ldBuildmode = "shared"
+	case "plugin":
+		pkgsFilter = oneMainPkg
+		if gccgo {
+			codegenArg = "-fPIC"
+		} else {
+			codegenArg = "-dynlink"
+		}
+		cfg.ExeSuffix = ".so"
+		ldBuildmode = "plugin"
+	default:
+		base.Fatalf("buildmode=%s not supported", cfg.BuildBuildmode)
+	}
+
+	if !sys.BuildModeSupported(cfg.BuildToolchainName, cfg.BuildBuildmode, cfg.Goos, cfg.Goarch) {
+		base.Fatalf("-buildmode=%s not supported on %s/%s\n", cfg.BuildBuildmode, cfg.Goos, cfg.Goarch)
+	}
+
+	if cfg.BuildLinkshared {
+		if !sys.BuildModeSupported(cfg.BuildToolchainName, "shared", cfg.Goos, cfg.Goarch) {
+			base.Fatalf("-linkshared not supported on %s/%s\n", cfg.Goos, cfg.Goarch)
+		}
+		if gccgo {
+			codegenArg = "-fPIC"
+		} else {
+			forcedAsmflags = append(forcedAsmflags, "-D=GOBUILDMODE_shared=1",
+				"-linkshared")
+			codegenArg = "-dynlink"
+			forcedGcflags = append(forcedGcflags, "-linkshared")
+			// TODO(mwhudson): remove -w when that gets fixed in linker.
+			forcedLdflags = append(forcedLdflags, "-linkshared", "-w")
+		}
+	}
+	if codegenArg != "" {
+		if gccgo {
+			forcedGccgoflags = append([]string{codegenArg}, forcedGccgoflags...)
+		} else {
+			forcedAsmflags = append([]string{codegenArg}, forcedAsmflags...)
+			forcedGcflags = append([]string{codegenArg}, forcedGcflags...)
+		}
+		// Don't alter InstallSuffix when modifying default codegen args.
+		if cfg.BuildBuildmode != "default" || cfg.BuildLinkshared {
+			if cfg.BuildContext.InstallSuffix != "" {
+				cfg.BuildContext.InstallSuffix += "_"
+			}
+			cfg.BuildContext.InstallSuffix += codegenArg[1:]
+		}
+	}
+
+	switch cfg.BuildMod {
+	case "":
+		// Behavior will be determined automatically, as if no flag were passed.
+	case "readonly", "vendor", "mod":
+		if !cfg.ModulesEnabled && !base.InGOFLAGS("-mod") {
+			base.Fatalf("build flag -mod=%s only valid when using modules", cfg.BuildMod)
+		}
+	default:
+		base.Fatalf("-mod=%s not supported (can be '', 'mod', 'readonly', or 'vendor')", cfg.BuildMod)
+	}
+	if !cfg.ModulesEnabled {
+		if cfg.ModCacheRW && !base.InGOFLAGS("-modcacherw") {
+			base.Fatalf("build flag -modcacherw only valid when using modules")
+		}
+		if cfg.ModFile != "" && !base.InGOFLAGS("-mod") {
+			base.Fatalf("build flag -modfile only valid when using modules")
+		}
+	}
+}