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To compile this program you require GNU Make. In fact you probably need
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GNU Make 3.76.1 or newer. The makefiles contained make use of many
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GNU Make specific features and will not run on other makes.
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The make system has a number of interesting properties that are not found
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in other systems such as automake or the GNU makefile standards. In
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general some semblance of expectedness is kept so as not to be too
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surprising. Basically the following will work as expected:
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There are a number of other things that are possible that may make software
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development and software packaging simpler. The first of these is the
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environment.mak file. When configure is run it creates an environment.mak
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file in the build directory. This contains -all- configurable parameters
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for all of the make files in all of the subdirectories. Changing one
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of these parameters will have an immediate effect. The use of makefile.in
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and configure substitutions across build makefiles is not used at all.
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Furthermore, the make system runs with a current directory equal to the
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source directory irregardless of the destination directory. This means
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#include "" and #include <> work as expected and more importantly
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running 'make' in the source directory will work as expected. The
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environment variable or make parameter 'BUILD' sets the build directory.
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It may be an absolute path or a path relative to the top level directory.
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By default build-arch/ then build/ will be used with a fall back to ./ This
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means you can get all the advantages of a build directory without having to
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cd into it to edit your source code!
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The make system also performs dependency generation on the fly as the
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compiler runs. This is extremely fast and accurate. There is however
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one failure condition that occures when a header file is erased. In
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this case you should run make clean to purge the .o and .d files to
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The final significant deviation from normal make practicies is
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in how the build directory is managed. It is not mearly a mirror of
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the source directory but is logically divided in the following manner
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Only .o and .d files are placed in the obj/ subdirectory. The final compiled
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binaries are placed in bin, published headers for inter-component linking
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are placed in include/ and documentation is generated into doc/. This means
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all runnable programs are within the bin/ directory, a huge benifit for
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debugging inter-program relationships. The .so files are also placed in
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By default make is put into silent mode. During operation there should be
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no shell or compiler messages only status messages from the makefiles,
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if any pop up that indicates there may be a problem with your environment.
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For debugging you can disable this by setting NOISY=1, ala
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The makefiles for the components are really simple. The complexity is hidden
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within the buildlib/ directory. Each makefile defines a set of make variables
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for the bit it is going to make then includes a makefile fragment from
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the buildlib/. This fragment generates the necessary rules based on the
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originally defined variables. This process can be repeated as many times as
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necessary for as many programs or libraries as are in the directory.
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Many of the make fragments have some useful properties involving sub
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directories and other interesting features. They are more completely
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described in the fragment code in buildlib. Some tips on writing fragments
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are included in buildlib/defaults.mak
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The fragments are NEVER processed by configure, so if you make changes to
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them they will have an immediate effect.
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Straight out of CVS you have to initialize autoconf. This requires
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automake (I really don't know why) and autoconf and requires doing
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[Altertatively you can run make startup in the top level build dir]
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Autoconf is configured to do some basic system probes for optional and
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required functionality and generate an environment.mak and include/config.h
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from it's findings. It will then write a 'makefile' and run make dirs to
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create the output directory tree.
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It is not my belief that autoconf should be used to generate substantial
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source code markup to escape OS problems. If an OS problem does crop up
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it can likely be corrected by installing the correct files into the
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build include/ dir and perhaps writing some replacement code and
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linking it in. To the fullest extent possible the source code should conform
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to standards and not cater to broken systems.
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Autoconf will also wite a makefile into the top level of the build dir,
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this simply acts as a wrapper to the main top level make in the source tree.
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There is one big warning, you can't use both this make file and the
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ones in the top level tree. Make is not able to resolve rules that
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go to the same file through different paths and this will confuse the
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depends mechanism. I recommend always using the makefiles in the
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source directory and exporting BUILD.
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apt-build/README.make
