1#!/usr/local/bin/bash
2# Copyright 2015 The Go Authors. All rights reserved.
3# Use of this source code is governed by a BSD-style
4# license that can be found in the LICENSE file.
5
6# When run as (for example)
7#
8#	GOOS=linux GOARCH=ppc64 bootstrap.bash
9#
10# this script cross-compiles a toolchain for that GOOS/GOARCH
11# combination, leaving the resulting tree in ../../go-${GOOS}-${GOARCH}-bootstrap.
12# That tree can be copied to a machine of the given target type
13# and used as $GOROOT_BOOTSTRAP to bootstrap a local build.
14#
15# Only changes that have been committed to Git (at least locally,
16# not necessary reviewed and submitted to master) are included in the tree.
17#
18# As a special case for Go's internal use only, if the
19# BOOTSTRAP_FORMAT environment variable is set to "mintgz", the
20# resulting archive is intended for use by the Go build system and
21# differs in that the mintgz file:
22#   * is a tar.gz file instead of bz2
23#   * has many unnecessary files deleted to reduce its size
24#   * does not have a shared directory component for each tar entry
25# Do not depend on the mintgz format.
26
27set -e
28
29if [ "$GOOS" = "" -o "$GOARCH" = "" ]; then
30	echo "usage: GOOS=os GOARCH=arch ./bootstrap.bash" >&2
31	exit 2
32fi
33
34targ="../../go-${GOOS}-${GOARCH}-bootstrap"
35if [ -e $targ ]; then
36	echo "$targ already exists; remove before continuing"
37	exit 2
38fi
39
40if [ "$BOOTSTRAP_FORMAT" != "mintgz" -a "$BOOTSTRAP_FORMAT" != "" ]; then
41	echo "unknown BOOTSTRAP_FORMAT format"
42	exit 2
43fi
44
45unset GOROOT
46src=$(cd .. && pwd)
47echo "#### Copying to $targ"
48cp -Rp "$src" "$targ"
49cd "$targ"
50echo
51echo "#### Cleaning $targ"
52chmod -R +w .
53rm -f .gitignore
54if [ -e .git ]; then
55	git clean -f -d
56fi
57echo
58echo "#### Building $targ"
59echo
60cd src
61./make.bash --no-banner
62gohostos="$(../bin/go env GOHOSTOS)"
63gohostarch="$(../bin/go env GOHOSTARCH)"
64goos="$(../bin/go env GOOS)"
65goarch="$(../bin/go env GOARCH)"
66
67# NOTE: Cannot invoke go command after this point.
68# We're about to delete all but the cross-compiled binaries.
69cd ..
70if [ "$goos" = "$gohostos" -a "$goarch" = "$gohostarch" ]; then
71	# cross-compile for local system. nothing to copy.
72	# useful if you've bootstrapped yourself but want to
73	# prepare a clean toolchain for others.
74	true
75else
76	rm -f bin/go_${goos}_${goarch}_exec
77	mv bin/*_*/* bin
78	rmdir bin/*_*
79	rm -rf "pkg/${gohostos}_${gohostarch}" "pkg/tool/${gohostos}_${gohostarch}"
80fi
81
82if [ "$BOOTSTRAP_FORMAT" = "mintgz" ]; then
83	# Fetch git revision before rm -rf .git.
84	GITREV=$(git rev-parse --short HEAD)
85fi
86
87rm -rf pkg/bootstrap pkg/obj .git
88
89# Support for building minimal tar.gz for the builders.
90# The build system doesn't support bzip2, and by deleting more stuff,
91# they start faster, especially on machines without fast filesystems
92# and things like tmpfs configures.
93# Do not depend on this format. It's for internal use only.
94if [ "$BOOTSTRAP_FORMAT" = "mintgz" ]; then
95	OUTGZ="gobootstrap-${GOOS}-${GOARCH}-${GITREV}.tar.gz"
96	echo "Preparing to generate build system's ${OUTGZ}; cleaning ..."
97	rm -rf bin/gofmt
98	rm -rf src/runtime/race/race_*.syso
99	rm -rf api test doc misc/cgo/test misc/trace
100	rm -rf pkg/tool/*_*/{addr2line,api,cgo,cover,doc,fix,nm,objdump,pack,pprof,test2json,trace,vet}
101	rm -rf pkg/*_*/{image,database,cmd}
102	rm -rf $(find . -type d -name testdata)
103	find . -type f -name '*_test.go' -exec rm {} \;
104	# git clean doesn't clean symlinks apparently, and the buildlet
105	# rejects them, so:
106	find . -type l -exec rm {} \;
107
108	echo "Writing ${OUTGZ} ..."
109	tar cf - . | gzip -9 > ../$OUTGZ
110	cd ..
111	ls -l "$(pwd)/$OUTGZ"
112	exit 0
113fi
114
115echo ----
116echo Bootstrap toolchain for "$GOOS/$GOARCH" installed in "$(pwd)".
117echo Building tbz.
118cd ..
119tar cf - "go-${GOOS}-${GOARCH}-bootstrap" | bzip2 -9 >"go-${GOOS}-${GOARCH}-bootstrap.tbz"
120ls -l "$(pwd)/go-${GOOS}-${GOARCH}-bootstrap.tbz"
121exit 0
122