build: allow clean.bash to work on fresh checkout

Must be invoked as ./clean.bash --gomake make
(or --gomake gmake, depending on the name of
GNU make).

R=niemeyer
CC=golang-dev
https://golang.org/cl/4023065

src/clean.bash

@@ -25,8 +25,8 @@ for i in lib9 libbio libmach cmd pkg \
 do(
 	cd "$GOROOT"/src/$i || exit 1
 	if test -f clean.bash; then
-		bash clean.bash
+		bash clean.bash --gomake $MAKE
 	else
-		gomake clean
+		$MAKE clean
 	fi
 )done

src/cmd/clean.bash

@@ -3,9 +3,14 @@
 # Use of this source code is governed by a BSD-style
 # license that can be found in the LICENSE file.
 
+gomake=gomake
+if [ $1 == "--gomake" -a "$2" != "" ]; then
+	gomake=$2
+fi
+
 for i in cc 6l 6a 6c 8l 8a 8c 8g 5l 5a 5c 5g gc 6g gopack nm cgo cov ebnflint godefs godoc gofmt goinstall gotest goyacc hgpatch prof
 do
 	cd $i
-	gomake clean
+	$gomake clean
 	cd ..
 done

src/pkg/Makefile

@@ -211,19 +211,19 @@ test.dirs: $(addsuffix .test, $(TEST))
 bench.dirs: $(addsuffix .bench, $(BENCH))
 
 %.clean:
-	+cd $* && gomake clean
+	+cd $* && $(MAKE) clean
 
 %.install:
-	+cd $* && gomake install
+	+cd $* && $(MAKE) install
 
 %.nuke:
-	+cd $* && gomake nuke
+	+cd $* && $(MAKE) nuke
 
 %.test:
-	+cd $* && gomake test
+	+cd $* && $(MAKE) test
 
 %.bench:
-	+cd $* && gomake bench
+	+cd $* && $(MAKE) bench
 
 clean: clean.dirs