// turn them into weak relocs.
	if fn.IsPackageInit() && base.Debug.WrapGlobalMapCtl != 1 {
		weakenGlobalMapInitRelocs(fn)
	}

	// fieldtrack must be called after pp.Flush. See issue 20014.
	fieldtrack(pp.Text.From.Sym, fn.FieldTrack)
}

// globalMapInitLsyms records the LSym of each map.init.NNN outlined
// map initializer function created by the compiler.

	bench.Start("deadcode")
	deadcode(ctxt)

	bench.Start("linksetup")
	ctxt.linksetup()

	bench.Start("dostrdata")
	ctxt.dostrdata()
	if buildcfg.Experiment.FieldTrack {
		bench.Start("fieldtrack")
		fieldtrack(ctxt.Arch, ctxt.loader)
	}

	bench.Start("dwarfGenerateDebugInfo")
	dwarfGenerateDebugInfo(ctxt)

	bench.Start("callgraph")
	ctxt.callgraph()

	bench.Start("doStackCheck")

//
// For the baseline experimental configuration, see
// objabi.experimentBaseline.
//
// If you change this struct definition, run "go generate".
type Flags struct {
	FieldTrack        bool
	PreemptibleLoops  bool
	StaticLockRanking bool
	BoringCrypto      bool

	// Regabi is split into several sub-experiments that can be
	// enabled individually. Not all combinations work.

	-installsuffix suffix
		Look for packages in $GOROOT/pkg/$GOOS_$GOARCH_suffix
		instead of $GOROOT/pkg/$GOOS_$GOARCH.
	-k symbol
		Set field tracking symbol. Use this flag when GOEXPERIMENT=fieldtrack is set.
	-libgcc file
		Set name of compiler support library.
		This is only used in internal link mode.
		If not set, default value comes from running the compiler,
		which may be set by the -extld option.

	}
	if outer.Sym() == nil {
		base.Errorf("tracked field must be in named struct type")
	}

	sym := reflectdata.TrackSym(outer, field)
	if ir.CurFunc.FieldTrack == nil {
		ir.CurFunc.FieldTrack = make(map[*obj.LSym]struct{})
	}
	ir.CurFunc.FieldTrack[sym] = struct{}{}

# go env -w checks validity of GOEXPERIMENT
env GOEXPERIMENT=
! go env -w GOEXPERIMENT=badexp
stderr 'unknown GOEXPERIMENT badexp'
go env -w GOEXPERIMENT=fieldtrack

# go env -w and go env -u work on unknown fields already in the go/env file
cp bad.env $GOENV
go env GOENV
cat $GOENV
go env
! stdout UNKNOWN
go env UNKNOWN
stdout yes
go env -w UNKNOWN=maybe

	mapinitnoop   loader.Sym
}

func (d *deadcodePass) init() {
	d.ldr.InitReachable()
	d.ifaceMethod = make(map[methodsig]bool)
	d.genericIfaceMethod = make(map[string]bool)
	if buildcfg.Experiment.FieldTrack {
		d.ldr.Reachparent = make([]loader.Sym, d.ldr.NSym())
	}
	d.dynlink = d.ctxt.DynlinkingGo()

	if d.ctxt.BuildMode == BuildModeShared {
		// Mark all symbols defined in this library as reachable when

	// function. The root scope (0) has no parent, so the i'th
	// scope's parent is stored at Parents[i-1].
	Parents []ScopeID

	// Marks records scope boundary changes.
	Marks []Mark

	FieldTrack map[*obj.LSym]struct{}
	DebugInfo  interface{}
	LSym       *obj.LSym // Linker object in this function's native ABI (Func.ABI)

	Inl *Inline

	// RangeParent, if non-nil, is the first non-range body function containing

		// Not set. Use default.
	default:
		log.Fatalf("GO19CONCURRENTCOMPILATION must be 0, 1, or unset, got %q", e)
	}

	// TODO: Test and delete these conditions.
	if cfg.ExperimentErr != nil || cfg.Experiment.FieldTrack || cfg.Experiment.PreemptibleLoops {
		canDashC = false
	}

	if !canDashC {
		return 1
	}

	// Decide how many concurrent backend compilations to allow.
	//