_README_

use as

go build -gantt <project> 2> build.html

then add <table> and </table> to the beginning and end of build.html

gantt.diff

diff --git a/src/cmd/go/build.go b/src/cmd/go/build.go
index 5977828..41fc630 100644
--- a/src/cmd/go/build.go
+++ b/src/cmd/go/build.go
@@ -76,6 +76,7 @@ and test commands:
 		and only with Clang/LLVM as the host C compiler.
 	-v
 		print the names of packages as they are compiled.
+	-gantt
 	-work
 		print the name of the temporary work directory and
 		do not delete it when exiting.
@@ -163,6 +164,7 @@ var buildA bool               // -a flag
 var buildN bool               // -n flag
 var buildP = runtime.NumCPU() // -p flag
 var buildV bool               // -v flag
+var buildGantt bool           // -gantt flag
 var buildX bool               // -x flag
 var buildI bool               // -i flag
 var buildO = cmdBuild.Flag.String("o", "", "output file")
@@ -220,6 +222,7 @@ func addBuildFlags(cmd *Command) {
 	cmd.Flag.BoolVar(&buildN, "n", false, "")
 	cmd.Flag.IntVar(&buildP, "p", buildP, "")
 	cmd.Flag.BoolVar(&buildV, "v", false, "")
+	cmd.Flag.BoolVar(&buildGantt, "gantt", false, "")
 	cmd.Flag.BoolVar(&buildX, "x", false, "")
 
 	cmd.Flag.Var((*stringsFlag)(&buildAsmflags), "asmflags", "")
@@ -1334,6 +1337,12 @@ func hasString(strings []string, s string) bool {
 	return false
 }
 
+var globalStart time.Time
+
+func init() {
+	globalStart = time.Now()
+}
+
 // build is the action for building a single package or command.
 func (b *builder) build(a *action) (err error) {
 	// Return an error if the package has CXX files but it's not using
@@ -1370,6 +1379,19 @@ func (b *builder) build(a *action) (err error) {
 	if buildV {
 		b.print(a.p.ImportPath + "\n")
 	}
+	if buildGantt {
+		start := time.Now()
+		defer func() {
+			finish := time.Now()
+			begin := start.Sub(globalStart)
+			total := finish.Sub(start)
+
+			title := fmt.Sprintf("<td>%v</td>", a.p.ImportPath)
+			time := fmt.Sprintf("<td>%v</td>", total)
+			block := fmt.Sprintf("<td><div style='margin-left:%vpx; width:%vpx; background: #f88;'>&nbsp;</div></td>", begin.Seconds()*20, total.Seconds()*20)
+			b.print("<tr>" + title + time + block + "</tr>")
+		}()
+	}
 
 	// Make build directory.
 	obj := a.objdir