blob: 9fe7f211fb3024951e24ce2f0f6f66f9572f2fb0 [file] [log] [blame]
// Copyright 2021 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 buildcfg provides access to the build configuration
// described by the current environment. It is for use by build tools
// such as cmd/go or cmd/compile and for setting up go/build's Default context.
//
// Note that it does NOT provide access to the build configuration used to
// build the currently-running binary. For that, use runtime.GOOS etc
// as well as internal/goexperiment.
package buildcfg
import (
"fmt"
"os"
"path/filepath"
"strings"
)
var (
defaultGOROOT string // set by linker
GOROOT = envOr("GOROOT", defaultGOROOT)
GOARCH = envOr("GOARCH", defaultGOARCH)
GOOS = envOr("GOOS", defaultGOOS)
GO386 = envOr("GO386", defaultGO386)
GOARM = goarm()
GOMIPS = gomips()
GOMIPS64 = gomips64()
GOPPC64 = goppc64()
GOWASM = gowasm()
GO_LDSO = defaultGO_LDSO
Version = version
)
// Error is one of the errors found (if any) in the build configuration.
var Error error
// Check exits the program with a fatal error if Error is non-nil.
func Check() {
if Error != nil {
fmt.Fprintf(os.Stderr, "%s: %v\n", filepath.Base(os.Args[0]), Error)
os.Exit(2)
}
}
func envOr(key, value string) string {
if x := os.Getenv(key); x != "" {
return x
}
return value
}
func goarm() int {
def := defaultGOARM
if GOOS == "android" && GOARCH == "arm" {
// Android arm devices always support GOARM=7.
def = "7"
}
switch v := envOr("GOARM", def); v {
case "5":
return 5
case "6":
return 6
case "7":
return 7
}
Error = fmt.Errorf("invalid GOARM: must be 5, 6, 7")
return int(def[0] - '0')
}
func gomips() string {
switch v := envOr("GOMIPS", defaultGOMIPS); v {
case "hardfloat", "softfloat":
return v
}
Error = fmt.Errorf("invalid GOMIPS: must be hardfloat, softfloat")
return defaultGOMIPS
}
func gomips64() string {
switch v := envOr("GOMIPS64", defaultGOMIPS64); v {
case "hardfloat", "softfloat":
return v
}
Error = fmt.Errorf("invalid GOMIPS64: must be hardfloat, softfloat")
return defaultGOMIPS64
}
func goppc64() int {
switch v := envOr("GOPPC64", defaultGOPPC64); v {
case "power8":
return 8
case "power9":
return 9
}
Error = fmt.Errorf("invalid GOPPC64: must be power8, power9")
return int(defaultGOPPC64[len("power")] - '0')
}
type gowasmFeatures struct {
SignExt bool
SatConv bool
}
func (f gowasmFeatures) String() string {
var flags []string
if f.SatConv {
flags = append(flags, "satconv")
}
if f.SignExt {
flags = append(flags, "signext")
}
return strings.Join(flags, ",")
}
func gowasm() (f gowasmFeatures) {
for _, opt := range strings.Split(envOr("GOWASM", ""), ",") {
switch opt {
case "satconv":
f.SatConv = true
case "signext":
f.SignExt = true
case "":
// ignore
default:
Error = fmt.Errorf("invalid GOWASM: no such feature %q", opt)
}
}
return
}
func Getgoextlinkenabled() string {
return envOr("GO_EXTLINK_ENABLED", defaultGO_EXTLINK_ENABLED)
}