[vala] building.txt: Update to mention vala-bootstrap

[Colin Walters <walters src gnome org>]

commit 4016d04899aabaa28b84f004926fd1fa5e2e4519
Author: Colin Walters <walters verbum org>
Date:   Mon Aug 6 10:25:51 2012 -0400

    building.txt: Update to mention vala-bootstrap

 doc/building.txt |   30 +++++++++++++++---------------
 1 files changed, 15 insertions(+), 15 deletions(-)
---
diff --git a/doc/building.txt b/doc/building.txt
index ad205eb..e340f50 100644
--- a/doc/building.txt
+++ b/doc/building.txt
@@ -7,39 +7,39 @@ TODO: complete this list
 Step two:
 ---------
 
-Grab yourself a vala to c compiled release of vala. Vala is self-hosting so it
-needs another vala compiler to compile itself. Since vala compiles to C code,
-you can use a tarball release of vala to compile the generated C code of such
-a release into a working Vala compiler, that will compile the Vala compiler
-which you might have checked out from the repository
+Vala is self-hosting so it needs another vala compiler to compile
+itself.  If you don't have an existing vala installed (i.e. because
+you're bootstrapping or cross-compiling), you can use the
+vala-bootstrap module:
 
-http://live.gnome.org/Vala/Release
+http://git.gnome.org/browse/vala-bootstrap
 
-Step three:
------------
+See also:
 
-Compiling the release which you just grabbed:
+http://live.gnome.org/Vala/Release
 
-tar jxvf vala-x.y.x.tar.bz2
-cd vala-x.y.z
-./configure --prefix=/opt/vala-release
+Downloading and compiling the bootstrap module:
+
+git clone git://git.gnome.org/vala-bootstrap
+cd vala-bootstrap
+./autogen.sh --prefix=/opt/vala-bootstrap --disable-build-from-vala --disable-vapigen
 make && sudo make install
 
-Step four:
+Step three:
 ----------
 
 Compiling the newest Vala from the repository:
 
 git clone git://git.gnome.org/vala
 cd vala
-export VALAC=/opt/vala-release/bin/vala
+export VALAC=/opt/vala-bootstrap/bin/vala
 ./autogen.sh --prefix=/opt/vala
 make && sudo make install
 
 Maybe you want to compile the new Vala with itself. Then you simply go over
 it again:
 
-make distclean
+git clean -dfx
 export VALAC=/opt/vala/bin/vala
 ./autogen.sh --prefix=/opt/vala
 make && sudo make install