build: move final steps of make.bash, make.bat, make.rc into cmd/dist

This CL expands the job of "dist bootstrap" to be "finish make.bash".
I need to change that logic in upcoming CLs related to cmd/go
changes, and I'd rather not change it in three places in three different
shell script languages.

Change-Id: I545dc215e408289e4d0b28f7c2ffcd849d89ad3b
Reviewed-on: https://go-review.googlesource.com/72870
Reviewed-by: David Crawshaw <crawshaw@golang.org>

4 files changed, 113 insertions, 103 deletions

diff --git a/src/cmd/dist/build.go b/src/cmd/dist/build.go
index c395205c55..2d4b575a83 100644
--- a/src/cmd/dist/build.go
+++ b/src/cmd/dist/build.go
@@ -32,6 +32,7 @@ var (
 	goroot_final           string
 	goextlinkenabled       string
 	gogcflags              string // For running built compiler
+	goldflags              string
 	workdir                string
 	tooldir                string
 	oldgoos                string
@@ -984,8 +985,22 @@ func cmdenv() {
 
 // The bootstrap command runs a build from scratch,
 // stopping at having installed the go_bootstrap command.
+//
+// WARNING: This command runs after cmd/dist is built with Go 1.4.
+// It rebuilds and installs cmd/dist with the new toolchain, so other
+// commands (like "go tool dist test" in run.bash) can rely on bug fixes
+// made since Go 1.4, but this function cannot. In particular, the uses
+// of os/exec in this function cannot assume that
+//	cmd.Env = append(os.Environ(), "X=Y")
+// sets $X to Y in the command's environment. That guarantee was
+// added after Go 1.4, and in fact in Go 1.4 it was typically the opposite:
+// if $X was already present in os.Environ(), most systems preferred
+// that setting, not the new one.
 func cmdbootstrap() {
+	var noBanner bool
 	flag.BoolVar(&rebuildall, "a", rebuildall, "rebuild all")
+	flag.BoolVar(&noBanner, "no-banner", noBanner, "do not print banner")
+
 	xflagparse(0)
 
 	if isdir(pathf("%s/src/pkg", goroot)) {
@@ -1007,6 +1022,9 @@ func cmdbootstrap() {
 	checkCC()
 	bootstrapBuildTools()
 
+	// Remember old content of $GOROOT/bin for comparison below.
+	oldBinFiles, _ := filepath.Glob(pathf("%s/bin/*", goroot))
+
 	// For the main bootstrap, building for host os/arch.
 	oldgoos = goos
 	oldgoarch = goarch
@@ -1049,19 +1067,65 @@ func cmdbootstrap() {
 		go install(dir)
 	}
 	<-installed["cmd/go"]
+	xprintf("\n")
 
-	goos = oldgoos
-	goarch = oldgoarch
-	os.Setenv("GOARCH", goarch)
-	os.Setenv("GOOS", goos)
+	gogcflags = os.Getenv("GO_GCFLAGS") // we were using $BOOT_GO_GCFLAGS until now
+	goldflags = os.Getenv("GO_LDFLAGS")
 
-	// Build runtime for actual goos/goarch too.
-	if goos != gohostos || goarch != gohostarch {
-		installed["runtime"] = make(chan struct{})
-		install("runtime")
+	// Build full toolchain for host and (if different) for target.
+	if goos != oldgoos || goarch != oldgoarch {
+		os.Setenv("CC", defaultcc)
+		buildAll()
+		xprintf("\n")
+		goos = oldgoos
+		goarch = oldgoarch
+		os.Setenv("GOOS", goos)
+		os.Setenv("GOARCH", goarch)
+	}
+
+	os.Setenv("CC", defaultcctarget)
+	buildAll()
+
+	// Check that there are no new files in $GOROOT/bin other than
+	// go and gofmt and $GOOS_$GOARCH (target bin when cross-compiling).
+	binFiles, _ := filepath.Glob(pathf("%s/bin/*", goroot))
+	ok := map[string]bool{}
+	for _, f := range oldBinFiles {
+		ok[f] = true
+	}
+	for _, f := range binFiles {
+		elem := strings.TrimSuffix(filepath.Base(f), ".exe")
+		if !ok[f] && elem != "go" && elem != "gofmt" && elem != goos+"_"+goarch {
+			fatalf("unexpected new file in $GOROOT/bin: %s", elem)
+		}
+	}
+
+	// Remove go_bootstrap now that we're done.
+	xremove(pathf("%s/go_bootstrap", tooldir))
+
+	// Print trailing banner unless instructed otherwise.
+	if !noBanner {
+		banner()
 	}
 }
 
+func buildAll() {
+	desc := ""
+	if oldgoos != goos || oldgoarch != goarch {
+		desc = " host,"
+	}
+	xprintf("##### Building packages and commands for%s %s/%s.\n", desc, goos, goarch)
+	go_bootstrap := pathf("%s/go_bootstrap", tooldir)
+	go_install := []string{go_bootstrap, "install", "-v", "-gcflags=" + gogcflags, "-ldflags=" + goldflags}
+
+	// Force only one process at a time on vx32 emulation.
+	if gohostos == "plan9" && os.Getenv("sysname") == "vx32" {
+		go_install = append(go_install, "-p=1")
+	}
+
+	run(pathf("%s/src", goroot), ShowOutput|CheckExit, append(go_install, "std", "cmd")...)
+}
+
 // Cannot use go/build directly because cmd/dist for a new release
 // builds against an old release's go/build, which may be out of sync.
 // To reduce duplication, we generate the list for go/build from this.
@@ -1176,7 +1240,10 @@ func cmdclean() {
 // Banner prints the 'now you've installed Go' banner.
 func cmdbanner() {
 	xflagparse(0)
+	banner()
+}
 
+func banner() {
 	xprintf("\n")
 	xprintf("---\n")
 	xprintf("Installed Go for %s/%s in %s\n", goos, goarch, goroot)
diff --git a/src/make.bash b/src/make.bash
index 3804b46b03..4e1b7b6bd8 100755
--- a/src/make.bash
+++ b/src/make.bash
@@ -50,6 +50,7 @@
 # PKG_CONFIG: Path to pkg-config tool. Default is "pkg-config".
 #
 # GO_DISTFLAGS: extra flags to provide to "dist bootstrap".
+# (Or just pass them to the make.bash command line.)
 
 set -e
 
@@ -164,40 +165,15 @@ if [ "$1" = "--no-clean" ]; then
 	buildall=""
 	shift
 fi
-./cmd/dist/dist bootstrap $buildall $GO_DISTFLAGS -v # builds go_bootstrap
 
-# Delay move of dist tool to now, because bootstrap may clear tool directory.
-mv cmd/dist/dist "$GOTOOLDIR"/dist
-echo
-
-if [ "$GOHOSTARCH" != "$GOARCH" -o "$GOHOSTOS" != "$GOOS" ]; then
-	echo "##### Building packages and commands for host, $GOHOSTOS/$GOHOSTARCH."
-	# CC_FOR_TARGET is recorded as the default compiler for the go tool. When building for the host, however,
-	# use the host compiler, CC, from `cmd/dist/dist env` instead.
-	CC=$CC GOOS=$GOHOSTOS GOARCH=$GOHOSTARCH \
-		"$GOTOOLDIR"/go_bootstrap install -gcflags "$GO_GCFLAGS" -ldflags "$GO_LDFLAGS" -v std cmd
-	echo
-fi
-
-echo "##### Building packages and commands for $GOOS/$GOARCH."
-
-old_bin_files=$(cd $GOROOT/bin && echo *)
-
-CC=$CC_FOR_TARGET "$GOTOOLDIR"/go_bootstrap install $GO_FLAGS -gcflags "$GO_GCFLAGS" -ldflags "$GO_LDFLAGS" -v std cmd
-
-# Check that there are no new files in $GOROOT/bin other than go and gofmt
-# and $GOOS_$GOARCH (a directory used when cross-compiling).
-(cd $GOROOT/bin && for f in *; do
-	if ! expr " $old_bin_files go gofmt ${GOOS}_${GOARCH} " : ".* $f " >/dev/null 2>/dev/null; then
-		echo 1>&2 "ERROR: unexpected new file in $GOROOT/bin: $f"
-		exit 1
-	fi
-done)
-
-echo
-
-rm -f "$GOTOOLDIR"/go_bootstrap
-
-if [ "$1" != "--no-banner" ]; then
-	"$GOTOOLDIR"/dist banner
-fi
+# Run dist bootstrap to complete make.bash.
+# Bootstrap installs a proper cmd/dist, built with the new toolchain.
+# Throw ours, built with Go 1.4, away after bootstrap.
+./cmd/dist/dist bootstrap $buildall -v $GO_DISTFLAGS "$@"
+rm -f ./cmd/dist/dist
+
+# DO NOT ADD ANY NEW CODE HERE.
+# The bootstrap+rm above are the final step of make.bash.
+# If something must be added, add it to cmd/dist's cmdbootstrap,
+# to avoid needing three copies in three different shell languages
+# (make.bash, make.bat, make.rc).
diff --git a/src/make.bat b/src/make.bat
index bf25b95ca5..101fc4bb1a 100644
--- a/src/make.bat
+++ b/src/make.bat
@@ -83,44 +83,24 @@ if x%2==x--dist-tool goto copydist
 
 set buildall=-a
 if x%1==x--no-clean set buildall=
-.\cmd\dist\dist bootstrap %buildall% -v
-if errorlevel 1 goto fail
-:: Delay move of dist tool to now, because bootstrap cleared tool directory.
-move .\cmd\dist\dist.exe "%GOTOOLDIR%\dist.exe"
-echo.
-
-if not %GOHOSTARCH% == %GOARCH% goto localbuild
-if not %GOHOSTOS% == %GOOS% goto localbuild
-goto mainbuild
-
-:localbuild
-echo ##### Building packages and commands for host, %GOHOSTOS%/%GOHOSTARCH%.
-:: CC_FOR_TARGET is recorded as the default compiler for the go tool. When building for the
-:: host, however, use the host compiler, CC, from `cmd/dist/dist env` instead.
-setlocal
-set GOOS=%GOHOSTOS%
-set GOARCH=%GOHOSTARCH%
-"%GOTOOLDIR%\go_bootstrap" install -gcflags "%GO_GCFLAGS%" -ldflags "%GO_LDFLAGS%" -v std cmd
-endlocal
-if errorlevel 1 goto fail
-echo.
+if x%2==x--no-clean set buildall=
+if x%1==x--no-banner set buildall=%buildall% --no-banner
+if x%2==x--no-banner set buildall=%buildall% --no-banner
 
-:mainbuild
-echo ##### Building packages and commands for %GOOS%/%GOARCH%.
-setlocal
-set CC=%CC_FOR_TARGET%
-"%GOTOOLDIR%\go_bootstrap" install -gcflags "%GO_GCFLAGS%" -ldflags "%GO_LDFLAGS%" -a -v std cmd
-endlocal
+:: Run dist bootstrap to complete make.bash.
+:: Bootstrap installs a proper cmd/dist, built with the new toolchain.
+:: Throw ours, built with Go 1.4, away after bootstrap.
+.\cmd\dist\dist bootstrap %buildall% -v
 if errorlevel 1 goto fail
-del "%GOTOOLDIR%\go_bootstrap.exe"
-echo.
-
-if x%1==x--no-banner goto nobanner
-"%GOTOOLDIR%\dist" banner
-:nobanner
-
+del .\cmd\dist\dist.exe
 goto end
 
+:: DO NOT ADD ANY NEW CODE HERE.
+:: The bootstrap+del above are the final step of make.bat.
+:: If something must be added, add it to cmd/dist's cmdbootstrap,
+:: to avoid needing three copies in three different shell languages
+:: (make.bash, make.bat, make.rc).
+
 :copydist
 mkdir "%GOTOOLDIR%" 2>NUL
 copy cmd\dist\dist.exe "%GOTOOLDIR%\"
diff --git a/src/make.rc b/src/make.rc
index 604e4a89c9..7704b12417 100755
--- a/src/make.rc
+++ b/src/make.rc
@@ -82,31 +82,18 @@ if(~ $1 --dist-tool){
 }
 
 buildall = -a
-if(~ $1 --no-clean)
+if(~ $1 --no-clean) {
 	buildall = ()
-./cmd/dist/dist bootstrap $buildall -v # builds go_bootstrap
-# Delay move of dist tool to now, because bootstrap may clear tool directory.
-mv cmd/dist/dist $GOTOOLDIR/dist
-echo
-
-# Run only one process at a time on 9vx.
-if(~ $sysname vx32)
-	pflag = (-p 1)
-
-if(! ~ $GOHOSTARCH $GOARCH || ! ~ $GOHOSTOS $GOOS){
-	echo '##### Building packages and commands for host,' $GOHOSTOS/$GOHOSTARCH^.
-	GOOS=$GOHOSTOS GOARCH=$GOHOSTARCH GOBIN=() \
-		$GOTOOLDIR/go_bootstrap install -gcflags $"GO_GCFLAGS -ldflags $"GO_LDFLAGS -v $pflag std cmd
-	echo
+	shift
 }
+# Run dist bootstrap to complete make.bash.
+# Bootstrap installs a proper cmd/dist, built with the new toolchain.
+# Throw ours, built with Go 1.4, away after bootstrap.
+./cmd/dist/dist bootstrap -v $buildall $*
+rm -f ./cmd/dist/dist
 
-echo '##### Building packages and commands for' $GOOS/$GOARCH^.
-$GOTOOLDIR/go_bootstrap install -gcflags $"GO_GCFLAGS -ldflags $"GO_LDFLAGS -v $pflag std cmd
-echo
-
-rm -f $GOTOOLDIR/go_bootstrap
-
-if(! ~ $1 --no-banner)
-	$GOTOOLDIR/dist banner
-
-status=''
+# DO NOT ADD ANY NEW CODE HERE.
+# The bootstrap+rm above are the final step of make.rc.
+# If something must be added, add it to cmd/dist's cmdbootstrap,
+# to avoid needing three copies in three different shell languages
+# (make.bash, make.bat, make.rc).