rebuild-stage1: use pkg order from reproducible build test

#573 (comment)

utils/rebuild-stage1.sh

@@ -2,6 +2,42 @@
 # use: rebuild-stage1.sh [no args]
 # Rebuilds the stage0/1 binaries with the stage 1 compiler.
 
-butch rebuild jobflow sabotage-core patch busybox binutils make \
-	kbd m4 gmp mpfr mpc libz libelf gcc640 musl 9base pkgconf \
-	libblkid e2fsprogs man join libressl ca-certificates
+# The resulting binaries/package directories should be
+# identical to binaries produced on different systems
+# (can be verified with `butch checksum`)
+
+base_pkg='
+libz
+gmp
+mpfr
+mpc
+libelf
+gcc640
+musl
+jobflow
+patch
+busybox
+binutils
+make
+sabotage-core
+join
+'
+
+ext_pkg='
+kbd
+m4
+9base
+pkgconf
+libblkid
+e2fsprogs
+man
+libressl
+ca-certificates
+'
+
+pkg="$base_pkg"
+test "$1" = --base || pkg="$base_pkg$ext_pkg"
+
+pkg=$(printf "%s\n" "$pkg" | sed '/^$/d' | tr '\n' ' ')
+
+butch rebuild $pkg