1 files changed, 127 insertions, 0 deletions
diff --git a/src/cmd/dist/buildgo.go b/src/cmd/dist/buildgo.go
new file mode 100644
index 0000000..caafc13
--- /dev/null
+++ b/src/cmd/dist/buildgo.go
@@ -0,0 +1,127 @@
+// Copyright 2012 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 main
+
+import (
+	"bytes"
+	"fmt"
+	"os"
+	"path/filepath"
+	"sort"
+	"strings"
+)
+
+/*
+ * Helpers for building cmd/go and cmd/cgo.
+ */
+
+// mkzdefaultcc writes zdefaultcc.go:
+//
+//	package main
+//	const defaultCC = <defaultcc>
+//	const defaultCXX = <defaultcxx>
+//	const defaultPkgConfig = <defaultpkgconfig>
+//
+// It is invoked to write cmd/go/internal/cfg/zdefaultcc.go
+// but we also write cmd/cgo/zdefaultcc.go
+func mkzdefaultcc(dir, file string) {
+	if strings.Contains(file, filepath.FromSlash("go/internal/cfg")) {
+		var buf bytes.Buffer
+		fmt.Fprintf(&buf, "// Code generated by go tool dist; DO NOT EDIT.\n")
+		fmt.Fprintln(&buf)
+		fmt.Fprintf(&buf, "package cfg\n")
+		fmt.Fprintln(&buf)
+		fmt.Fprintf(&buf, "const DefaultPkgConfig = `%s`\n", defaultpkgconfig)
+		buf.WriteString(defaultCCFunc("DefaultCC", defaultcc))
+		buf.WriteString(defaultCCFunc("DefaultCXX", defaultcxx))
+		writefile(buf.String(), file, writeSkipSame)
+		return
+	}
+
+	var buf bytes.Buffer
+	fmt.Fprintf(&buf, "// Code generated by go tool dist; DO NOT EDIT.\n")
+	fmt.Fprintln(&buf)
+	fmt.Fprintf(&buf, "package main\n")
+	fmt.Fprintln(&buf)
+	fmt.Fprintf(&buf, "const defaultPkgConfig = `%s`\n", defaultpkgconfig)
+	buf.WriteString(defaultCCFunc("defaultCC", defaultcc))
+	buf.WriteString(defaultCCFunc("defaultCXX", defaultcxx))
+	writefile(buf.String(), file, writeSkipSame)
+}
+
+func defaultCCFunc(name string, defaultcc map[string]string) string {
+	var buf bytes.Buffer
+
+	fmt.Fprintf(&buf, "func %s(goos, goarch string) string {\n", name)
+	fmt.Fprintf(&buf, "\tswitch goos+`/`+goarch {\n")
+	var keys []string
+	for k := range defaultcc {
+		if k != "" {
+			keys = append(keys, k)
+		}
+	}
+	sort.Strings(keys)
+	for _, k := range keys {
+		fmt.Fprintf(&buf, "\tcase %q:\n\t\treturn %q\n", k, defaultcc[k])
+	}
+	fmt.Fprintf(&buf, "\t}\n")
+	fmt.Fprintf(&buf, "\treturn %q\n", defaultcc[""])
+	fmt.Fprintf(&buf, "}\n")
+
+	return buf.String()
+}
+
+// mkzcgo writes zosarch.go for cmd/go.
+func mkzosarch(dir, file string) {
+	// sort for deterministic zosarch.go file
+	var list []string
+	for plat := range cgoEnabled {
+		list = append(list, plat)
+	}
+	sort.Strings(list)
+
+	var buf bytes.Buffer
+	fmt.Fprintf(&buf, "// Code generated by go tool dist; DO NOT EDIT.\n\n")
+	fmt.Fprintf(&buf, "package cfg\n\n")
+	fmt.Fprintf(&buf, "var OSArchSupportsCgo = map[string]bool{\n")
+	for _, plat := range list {
+		fmt.Fprintf(&buf, "\t%q: %v,\n", plat, cgoEnabled[plat])
+	}
+	fmt.Fprintf(&buf, "}\n")
+
+	writefile(buf.String(), file, writeSkipSame)
+}
+
+// mkzcgo writes zcgo.go for the go/build package:
+//
+//	package build
+//  var cgoEnabled = map[string]bool{}
+//
+// It is invoked to write go/build/zcgo.go.
+func mkzcgo(dir, file string) {
+	// sort for deterministic zcgo.go file
+	var list []string
+	for plat, hasCgo := range cgoEnabled {
+		if hasCgo {
+			list = append(list, plat)
+		}
+	}
+	sort.Strings(list)
+
+	var buf bytes.Buffer
+	fmt.Fprintf(&buf, "// Code generated by go tool dist; DO NOT EDIT.\n")
+	fmt.Fprintln(&buf)
+	fmt.Fprintf(&buf, "package build\n")
+	fmt.Fprintln(&buf)
+	fmt.Fprintf(&buf, "const defaultCGO_ENABLED = %q\n", os.Getenv("CGO_ENABLED"))
+	fmt.Fprintln(&buf)
+	fmt.Fprintf(&buf, "var cgoEnabled = map[string]bool{\n")
+	for _, plat := range list {
+		fmt.Fprintf(&buf, "\t%q: true,\n", plat)
+	}
+	fmt.Fprintf(&buf, "}\n")
+
+	writefile(buf.String(), file, writeSkipSame)
+}