//	  if *enableBenchmarking {
//	    bench = benchmark.New(benchmark.GC)
//	  }
//	  bench.Start("foo")
//	  // etc.
//	}
func New(gc Flags, filebase string) *Metrics {
	if gc == GC {
		runtime.GC()
	}
	return &Metrics{gc: gc, filebase: filebase}
}

// Report reports the metrics.
// Closes the currently Start(ed) range, and writes the report to the given io.Writer.
func (m *Metrics) Report(w io.Writer) {

              {{range .InlinedCalls -}}
                {{printf " %8s %10s %10s %8s  " "" "" "" "" -}}
                <span class=inlinesrc>{{.SrcLine}}</span>{{" " -}}
                <span class=unimportant>{{.FileBase}}:{{.Line}}</span>{{"\n" -}}
              {{end -}}

              {{if not .Synthetic -}}
                {{/* disassembled instruction */ -}}

func (pos Pos) Line() uint     { return uint(pos.line) }
func (pos Pos) Col() uint      { return uint(pos.col) }

// FileBase returns the PosBase of the file containing pos,
// skipping over intermediate PosBases from //line directives.
// The result is nil if pos doesn't have a file base.
func (pos Pos) FileBase() *PosBase {
	b := pos.base
	for b != nil && b != b.pos.base {
		b = b.pos.base
	}
	// b == nil || b == b.pos.base

// allowVersion returns true.
func (check *Checker) allowVersion(at poser, v goVersion) bool {
	fileVersion := check.conf.GoVersion
	if pos := at.Pos(); pos.IsKnown() {
		fileVersion = check.versions[pos.FileBase()]
	}

	// We need asGoVersion (which calls version.Lang) below
	// because fileVersion may be the (unaltered) Config.GoVersion
	// string which may contain dot-release information.
	version := asGoVersion(fileVersion)

				// (Ideally we would use the //build tag itself.)
				check.errorf(file.PkgName, TooNew, "file requires newer Go version %v", fileVersion)
			}
		}
		versions[file.Pos().FileBase()] = v // file.Pos().FileBase() may be nil for tests
	}
}

// A bailout panic is used for early termination.
type bailout struct{}

func (check *Checker) handleBailout(err *error) {
	switch p := recover().(type) {

	Disasm       string
	FileLine     string
	InlinedCalls []WebListCall
}

// WebListCall holds the per-inlined-call information for HTML source code listing.
type WebListCall struct {
	SrcLine  string
	FileBase string
	Line     int
}

// MakeWebList returns an annotated source listing of rpt.
// rpt.prof should contain inlined call info.