$Id$


1.0 Setting up the buildenvironment
-----------------------------------

The build environment is selfcontained with the exception of EMX. However,
some of the components changes rather often because of LIBC updates so these
components are kept in .zips which have to be unzipped in the /tools
directory. Go to tools/ and do unzip -o packages/*.zip.

The GCC is by default taken from tools/x86.os2/gcc/staged and you must put
the latest build there for it to work. Installing the compiler to that
directory is perhaps the best idea:
    GCC-3.2.2-beta4.exe /unattended /directory=tools/x86.os2/gcc/staged

The build environment is loaded into the current shell (4os2 or cmd) by
invoking tools\env.cmd. This rexx script takes two options:
    -disable-staged-gcc / -enable-staged-gcc:
        Use the staged gcc or the gcc322 BuildEnv. For the latter you'll
        have to put configure gcc322 using tools\buildenv.cmd if you haven't
        already done so globally for another project.

    -install / -uninstall:
        Install or uninstall the GCC buildenvironment. Installing it is
        naturally default. (Not sure how well -uninstall works actually.)

The rexx script takes one optional argument:
    RELEASE / DEBUG:
        Specifies the build mode/type which is to be default for the
        environment. Default is (of course) DEBUG.



2.0 Building
------------

The default for all is a simple build of all the components, no compiler
bootstrapping. However we do a little LIBC bootstrapping underways, i.e.
LIBC is build first and installed to a temporary location which figures
before the GCC one in all the PATHs. Thus the LIBC we build will be used
to build the rest. This will happen for the other libraries, tools,
binutils and gcc as we go along.

This build type is called 'quick'.


There is another build type, which is used for the release builds, which
is called double-quick. It performs the 'quick' build twice thus ensuring
that even everything is built with the same level of tools that we deliver.

Both 'quick' and 'double-quick' will log to obj/OS2/$(BUILD_MODE)/???.log,
and will when all is built install it into bin/OS2/$(BUILD_MODE)/<reltag>.


2.1 Building parts
------------------

Individual components can be built, like for instance LIBC/EMX can be built
from the src/emx directory. See help screen when invoking make there and the
MoBuS documentation in src/emx/build.txt

Binutils and GCC are normal GNU build system stuff, which mean they require
their Configure scripts to be run. This normally should be done by the root
Makefile to get it right. There are special gcc-configure, binutils-configure
rules for this. The object directories are in obj/OS2/$(BUILD_MODE)/gcc or
binutils.
TODO: Add emx-shell, gcc-shell and binutils-shell rules which will take you
to the right place.


3.0 Packing
-----------

There is a 'packing' rule. Just invoke this and packing will take place. To
pack up the sources invoke the 'packing-src' rule. The 'installer' will only
do the installer creation.