buildcfg

Documentation

Overview

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.

Index

• Constants
• Variables
• func Check()
• func GOGOARCH() (name, value string)
• func Getgoextlinkenabled() string
• type ExperimentFlags
  • func ParseGOEXPERIMENT(goos, goarch, goexp string) (*ExperimentFlags, error)
  • func (exp *ExperimentFlags) All() []string
  • func (exp *ExperimentFlags) Enabled() []string
  • func (exp *ExperimentFlags) String() string
• type Goarm64Features
  • func ParseGoarm64(v string) (g Goarm64Features, e error)
  • func (g Goarm64Features) String() string
  • func (g Goarm64Features) Supports(s string) bool

Constants

const DefaultGOEXPERIMENT = defaultGOEXPERIMENT

DefaultGOEXPERIMENT is the embedded default GOEXPERIMENT string. It is not guaranteed to be canonical.

Variables

var (
	GOROOT    = os.Getenv("GOROOT") // cached for efficiency
	GOARCH    = envOr("GOARCH", defaultGOARCH)
	GOOS      = envOr("GOOS", defaultGOOS)
	GO386     = envOr("GO386", defaultGO386)
	GOAMD64   = goamd64()
	GOARM     = goarm()
	GOARM64   = goarm64()
	GOMIPS    = gomips()
	GOMIPS64  = gomips64()
	GOPPC64   = goppc64()
	GORISCV64 = goriscv64()
	GOWASM    = gowasm()
	ToolTags  = toolTags()
	GO_LDSO   = defaultGO_LDSO
	Version   = version
)

var Error error

Error is one of the errors found (if any) in the build configuration.

var FramePointerEnabled = GOARCH == "amd64" || GOARCH == "arm64"

FramePointerEnabled enables the use of platform conventions for saving frame pointers.

This used to be an experiment, but now it's always enabled on platforms that support it.

Note: must agree with runtime.framepointer_enabled.

Functions

func Check

func Check()

Check exits the program with a fatal error if Error is non-nil.

func GOGOARCH

func GOGOARCH() (name, value string)

GOGOARCH returns the name and value of the GO$GOARCH setting. For example, if GOARCH is "amd64" it might return "GOAMD64", "v2".

func Getgoextlinkenabled

func Getgoextlinkenabled() string

Types

type ExperimentFlags

type ExperimentFlags struct {
	goexperiment.Flags
	// contains filtered or unexported fields
}

ExperimentFlags represents a set of GOEXPERIMENT flags relative to a baseline (platform-default) experiment configuration.

var Experiment ExperimentFlags = func() ExperimentFlags {
	flags, err := ParseGOEXPERIMENT(GOOS, GOARCH, envOr("GOEXPERIMENT", defaultGOEXPERIMENT))
	if err != nil {
		Error = err
		return ExperimentFlags{}
	}
	return *flags
}()

Experiment contains the toolchain experiments enabled for the current build.

(This is not necessarily the set of experiments the compiler itself was built with.)

experimentBaseline specifies the experiment flags that are enabled by default in the current toolchain. This is, in effect, the "control" configuration and any variation from this is an experiment.

func ParseGOEXPERIMENT

func ParseGOEXPERIMENT(goos, goarch, goexp string) (*ExperimentFlags, error)

ParseGOEXPERIMENT parses a (GOOS, GOARCH, GOEXPERIMENT) configuration tuple and returns the enabled and baseline experiment flag sets.

TODO(mdempsky): Move to internal/goexperiment.

func (*ExperimentFlags) All

func (exp *ExperimentFlags) All() []string

All returns a list of all experiment settings. Disabled experiments appear in the list prefixed by "no".

func (*ExperimentFlags) Enabled

func (exp *ExperimentFlags) Enabled() []string

Enabled returns a list of enabled experiments, as lower-cased experiment names.

func (*ExperimentFlags) String

func (exp *ExperimentFlags) String() string

String returns the canonical GOEXPERIMENT string to enable this experiment configuration. (Experiments in the same state as in the baseline are elided.)

type Goarm64Features

type Goarm64Features struct {
	Version string
	// Large Systems Extension
	LSE bool
	// ARM v8.0 Cryptographic Extension. It includes the following features:
	// * FEAT_AES, which includes the AESD and AESE instructions.
	// * FEAT_PMULL, which includes the PMULL, PMULL2 instructions.
	// * FEAT_SHA1, which includes the SHA1* instructions.
	// * FEAT_SHA256, which includes the SHA256* instructions.
	Crypto bool
}

func ParseGoarm64

func ParseGoarm64(v string) (g Goarm64Features, e error)

func (Goarm64Features) String

func (g Goarm64Features) String() string

func (Goarm64Features) Supports

func (g Goarm64Features) Supports(s string) bool

Returns true if g supports giving ARM64 ISA Note that this function doesn't accept / test suffixes (like ",lse" or ",crypto")