mirror of
https://github.com/tailscale/tailscale.git
synced 2024-12-04 23:45:34 +00:00
538c2e8f7c
We don't build a lot of tools with CGO, but we do build some, and it's extremely valuable for production services in particular to have symbols included - for perf and so on. I tested various other builds that could be affected negatively, in particular macOS/iOS, but those use split-dwarf already as part of their build path, and Android which does not currently use gocross. One binary which is normally 120mb only grew to 123mb, so the trade-off is definitely worthwhile in context. Updates tailscale/corp#20296 Signed-off-by: James Tucker <james@tailscale.com>
275 lines
9.4 KiB
Go
275 lines
9.4 KiB
Go
// Copyright (c) Tailscale Inc & AUTHORS
|
|
// SPDX-License-Identifier: BSD-3-Clause
|
|
|
|
package main
|
|
|
|
import (
|
|
"cmp"
|
|
"fmt"
|
|
"runtime"
|
|
"strings"
|
|
|
|
"tailscale.com/version/mkversion"
|
|
)
|
|
|
|
// Autoflags adjusts the commandline argv into a new commandline
|
|
// newArgv and envvar alterations in env.
|
|
func Autoflags(argv []string, goroot string) (newArgv []string, env *Environment, err error) {
|
|
return autoflagsForTest(argv, NewEnvironment(), goroot, runtime.GOOS, runtime.GOARCH, mkversion.Info)
|
|
}
|
|
|
|
func autoflagsForTest(argv []string, env *Environment, goroot, nativeGOOS, nativeGOARCH string, getVersion func() mkversion.VersionInfo) (newArgv []string, newEnv *Environment, err error) {
|
|
// This is where all our "automatic flag injection" decisions get
|
|
// made. Modifying this code will modify the environment variables
|
|
// and commandline flags that the final `go` tool invocation will
|
|
// receive.
|
|
//
|
|
// When choosing between making this code concise or readable,
|
|
// please err on the side of being readable. Our build
|
|
// environments are relatively complicated by Go standards, and we
|
|
// want to keep it intelligible and malleable for our future
|
|
// selves.
|
|
var (
|
|
subcommand = ""
|
|
|
|
cc = "cc"
|
|
targetOS = cmp.Or(env.Get("GOOS", ""), nativeGOOS)
|
|
targetArch = cmp.Or(env.Get("GOARCH", ""), nativeGOARCH)
|
|
buildFlags = []string{"-trimpath"}
|
|
cgoCflags = []string{"-O3", "-std=gnu11", "-g"}
|
|
cgoLdflags []string
|
|
ldflags []string
|
|
tags = []string{"tailscale_go"}
|
|
cgo = false
|
|
failReflect = false
|
|
)
|
|
if len(argv) > 1 {
|
|
subcommand = argv[1]
|
|
}
|
|
|
|
switch subcommand {
|
|
case "build", "env", "install", "run", "test", "list":
|
|
default:
|
|
return argv, env, nil
|
|
}
|
|
|
|
vi := getVersion()
|
|
ldflags = []string{
|
|
"-X", "tailscale.com/version.longStamp=" + vi.Long,
|
|
"-X", "tailscale.com/version.shortStamp=" + vi.Short,
|
|
"-X", "tailscale.com/version.gitCommitStamp=" + vi.GitHash,
|
|
"-X", "tailscale.com/version.extraGitCommitStamp=" + vi.OtherHash,
|
|
}
|
|
|
|
switch targetOS {
|
|
case "android":
|
|
cgo = env.Get("CGO_ENABLED", "0") == "1"
|
|
case "linux":
|
|
// Getting Go to build a static binary with cgo enabled is a
|
|
// minor ordeal. The incantations you apparently need are
|
|
// documented at: https://github.com/golang/go/issues/26492
|
|
tags = append(tags, "osusergo", "netgo")
|
|
cgo = targetOS == nativeGOOS && targetArch == nativeGOARCH
|
|
// When in a Nix environment, the gcc package is built with only dynamic
|
|
// versions of glibc. You can get a static version of glibc via
|
|
// pkgs.glibc.static, but then you are reliant on Nix's gcc wrapper
|
|
// magic to inject that as a -L path to linker invocations.
|
|
//
|
|
// We can't rely on that magic linker flag injection, because that
|
|
// injection breaks redo's go machinery for dynamic go+cgo linking due
|
|
// to flag ordering issues that we can't easily fix (since the nix
|
|
// machinery controls the flag ordering, not us).
|
|
//
|
|
// So, instead, we unset NIX_LDFLAGS in our nix shell, which disables
|
|
// the magic linker flag passing; and we have shell.nix drop the path to
|
|
// the static glibc files in GOCROSS_GLIBC_DIR. Finally, we reinject it
|
|
// into the build process here, so that the linker can find static glibc
|
|
// and complete a static-with-cgo linkage.
|
|
extldflags := []string{"-static"}
|
|
if glibcDir := env.Get("GOCROSS_GLIBC_DIR", ""); glibcDir != "" {
|
|
extldflags = append(extldflags, "-L", glibcDir)
|
|
}
|
|
// -extldflags, when it contains multiple external linker flags, must be
|
|
// quoted in its entirety as a member of -ldflags. Source:
|
|
// https://github.com/golang/go/issues/6234
|
|
ldflags = append(ldflags, fmt.Sprintf("'-extldflags=%s'", strings.Join(extldflags, " ")))
|
|
case "windowsdll":
|
|
// Fake GOOS that translates to "windows, but building .dlls not .exes"
|
|
targetOS = "windows"
|
|
cgo = true
|
|
buildFlags = append(buildFlags, "-buildmode=c-shared")
|
|
ldflags = append(ldflags, "-H", "windows", "-s")
|
|
cgoLdflags = append(cgoLdflags, "-static")
|
|
var mingwArch string
|
|
switch targetArch {
|
|
case "amd64":
|
|
mingwArch = "x86_64"
|
|
case "386":
|
|
mingwArch = "i686"
|
|
default:
|
|
return nil, nil, fmt.Errorf("unsupported GOARCH=%q when building with cgo", targetArch)
|
|
}
|
|
cc = fmt.Sprintf("%s-w64-mingw32-gcc", mingwArch)
|
|
case "windowsgui":
|
|
// Fake GOOS that translates to "windows, but building GUI .exes not console .exes"
|
|
targetOS = "windows"
|
|
ldflags = append(ldflags, "-H", "windowsgui", "-s")
|
|
case "windows":
|
|
ldflags = append(ldflags, "-H", "windows", "-s")
|
|
case "ios":
|
|
failReflect = true
|
|
fallthrough
|
|
case "darwin":
|
|
cgo = nativeGOOS == "darwin"
|
|
tags = append(tags, "omitidna", "omitpemdecrypt")
|
|
if env.IsSet("XCODE_VERSION_ACTUAL") {
|
|
// If we're building via Xcode, we must be making the extension
|
|
// version (as opposed to tailscaled on Mac).
|
|
tags = append(tags, "ts_macext")
|
|
|
|
var xcodeFlags []string
|
|
// Minimum OS version being targeted, results in
|
|
// e.g. -mmacosx-version-min=11.3, -miphoneos-version-min=15.0
|
|
switch {
|
|
case env.IsSet("XROS_DEPLOYMENT_TARGET"):
|
|
if env.Get("TARGET_DEVICE_PLATFORM_NAME", "") == "xrsimulator" {
|
|
xcodeFlags = append(xcodeFlags, "-mtargetos=xros"+env.Get("XROS_DEPLOYMENT_TARGET", "")+"-simulator")
|
|
} else {
|
|
xcodeFlags = append(xcodeFlags, "-mtargetos=xros"+env.Get("XROS_DEPLOYMENT_TARGET", ""))
|
|
}
|
|
case env.IsSet("IPHONEOS_DEPLOYMENT_TARGET"):
|
|
if env.Get("TARGET_DEVICE_PLATFORM_NAME", "") == "iphonesimulator" {
|
|
xcodeFlags = append(xcodeFlags, "-miphonesimulator-version-min="+env.Get("IPHONEOS_DEPLOYMENT_TARGET", ""))
|
|
} else {
|
|
xcodeFlags = append(xcodeFlags, "-miphoneos-version-min="+env.Get("IPHONEOS_DEPLOYMENT_TARGET", ""))
|
|
}
|
|
case env.IsSet("MACOSX_DEPLOYMENT_TARGET"):
|
|
xcodeFlags = append(xcodeFlags, "-mmacosx-version-min="+env.Get("MACOSX_DEPLOYMENT_TARGET", ""))
|
|
case env.IsSet("TVOS_DEPLOYMENT_TARGET"):
|
|
xcodeFlags = append(xcodeFlags, "-mtvos-version-min="+env.Get("TVOS_DEPLOYMENT_TARGET", ""))
|
|
default:
|
|
return nil, nil, fmt.Errorf("invoked by Xcode but couldn't figure out deployment target. Did Xcode change its envvars again?")
|
|
}
|
|
|
|
// Target-specific SDK directory. Must be passed as two
|
|
// words ("-isysroot PATH", not "-isysroot=PATH").
|
|
xcodeFlags = append(xcodeFlags, "-isysroot", env.Get("SDKROOT", ""))
|
|
|
|
// What does clang call the target GOARCH?
|
|
var clangArch string
|
|
switch targetArch {
|
|
case "amd64":
|
|
clangArch = "x86_64"
|
|
case "arm64":
|
|
clangArch = "arm64"
|
|
default:
|
|
return nil, nil, fmt.Errorf("unsupported GOARCH=%q when building from Xcode", targetArch)
|
|
}
|
|
xcodeFlags = append(xcodeFlags, "-arch", clangArch)
|
|
cgoCflags = append(cgoCflags, xcodeFlags...)
|
|
cgoLdflags = append(cgoLdflags, xcodeFlags...)
|
|
ldflags = append(ldflags, "-w")
|
|
}
|
|
}
|
|
|
|
// Finished computing the settings we want. Generate the modified
|
|
// commandline and environment modifications.
|
|
newArgv = append(newArgv, argv[:2]...) // Program name and `go` tool subcommand
|
|
|
|
filteredArgvPostSubcmd, originalTags := extractTags(argv[1], argv[2:])
|
|
|
|
newArgv = append(newArgv, buildFlags...)
|
|
tags = append(tags, originalTags...)
|
|
if len(tags) > 0 {
|
|
newArgv = append(newArgv, fmt.Sprintf("-tags=%s", strings.Join(tags, ",")))
|
|
}
|
|
if len(ldflags) > 0 {
|
|
newArgv = append(newArgv, "-ldflags", strings.Join(ldflags, " "))
|
|
}
|
|
newArgv = append(newArgv, filteredArgvPostSubcmd...)
|
|
|
|
env.Set("GOOS", targetOS)
|
|
env.Set("GOARCH", targetArch)
|
|
if !env.IsSet("GOARM") {
|
|
env.Set("GOARM", "5") // TODO: fix, see go/internal-bug/3092
|
|
}
|
|
env.Set("GOMIPS", "softfloat")
|
|
env.Set("CGO_ENABLED", boolStr(cgo))
|
|
env.Set("CGO_CFLAGS", strings.Join(cgoCflags, " "))
|
|
env.Set("CGO_LDFLAGS", strings.Join(cgoLdflags, " "))
|
|
env.Set("CC", cc)
|
|
env.Set("TS_LINK_FAIL_REFLECT", boolStr(failReflect))
|
|
env.Set("GOROOT", goroot)
|
|
env.Set("GOTOOLCHAIN", "local")
|
|
|
|
if subcommand == "env" {
|
|
return argv, env, nil
|
|
}
|
|
|
|
return newArgv, env, nil
|
|
}
|
|
|
|
// extractTags parses out "-tags=foo,bar" (or double hyphen or "-tags",
|
|
// "foo,bar") in its various forms and returns v filtered to remove the 0, 1 or
|
|
// 2 build tag elements, then the tags parsed, split on commas ("foo", "bar").
|
|
func extractTags(gocmd string, v []string) (filtered, tags []string) {
|
|
for len(v) > 0 {
|
|
e := v[0]
|
|
if strings.HasPrefix(e, "--tags=") {
|
|
e = e[1:] // remove one of the hyphens for the next line
|
|
}
|
|
if suf, ok := strings.CutPrefix(e, "-tags="); ok {
|
|
v = v[1:]
|
|
if suf != "" {
|
|
tags = strings.Split(suf, ",")
|
|
}
|
|
continue
|
|
}
|
|
if e == "-tags" || e == "--tags" {
|
|
v = v[1:]
|
|
if len(v) > 0 {
|
|
tagStr := v[0]
|
|
v = v[1:]
|
|
if tagStr != "" {
|
|
tags = strings.Split(tagStr, ",")
|
|
}
|
|
}
|
|
continue
|
|
}
|
|
if gocmd == "run" && !strings.HasPrefix(e, "-") {
|
|
// go run can include arguments to pass to the program
|
|
// being run. They all appear after the name of the
|
|
// package or Go file to run, so when we hit the first
|
|
// non-flag positional argument, stop extracting tags and
|
|
// wrap up.
|
|
filtered = append(filtered, v...)
|
|
break
|
|
}
|
|
filtered = append(filtered, e)
|
|
v = v[1:]
|
|
}
|
|
return filtered, tags
|
|
}
|
|
|
|
// boolStr formats v as a string 0 or 1.
|
|
// Used because CGO_ENABLED doesn't strconv.ParseBool, so
|
|
// strconv.FormatBool breaks.
|
|
func boolStr(v bool) string {
|
|
if v {
|
|
return "1"
|
|
}
|
|
return "0"
|
|
}
|
|
|
|
// formatArgv formats a []string similarly to %v, but quotes each
|
|
// string so that the reader can clearly see each array element.
|
|
func formatArgv(v []string) string {
|
|
var ret strings.Builder
|
|
ret.WriteByte('[')
|
|
for _, s := range v {
|
|
fmt.Fprintf(&ret, "%q ", s)
|
|
}
|
|
ret.WriteByte(']')
|
|
return ret.String()
|
|
}
|