diff options
author | Julian Andres Klode <jak@debian.org> | 2016-08-10 16:19:00 +0200 |
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committer | Julian Andres Klode <jak@debian.org> | 2016-08-10 16:19:00 +0200 |
commit | e02c3a9ec2b2f7a8d4aecd70f2ecdae27c207aa9 (patch) | |
tree | ffa99f96949f3eab728a1b8caecdd014ea8d6f81 /README.make | |
parent | b2cfacf1180e4b3fcbb2ae2ea52cf270ef74e971 (diff) | |
parent | 61fef4ddbec8f70bb9e213ac0491d4e6cfefab30 (diff) |
Merge branch 'cmake'
Diffstat (limited to 'README.make')
-rw-r--r-- | README.make | 112 |
1 files changed, 0 insertions, 112 deletions
diff --git a/README.make b/README.make deleted file mode 100644 index db5f36e94..000000000 --- a/README.make +++ /dev/null @@ -1,112 +0,0 @@ -The Make System -~~~ ~~~~ ~~~~~~ -To compile this program you require GNU Make. In fact you probably need -GNU Make 3.76.1 or newer. The makefiles contained make use of many -GNU Make specific features and will not run on other makes. - -The make system has a number of interesting properties that are not found -in other systems such as automake or the GNU makefile standards. In -general some semblance of expectedness is kept so as not to be too -surprising. Basically the following will work as expected: - - ./configure - make - or - cd build - ../configure - make - -There are a number of other things that are possible that may make software -development and software packaging simpler. The first of these is the -environment.mak file. When configure is run it creates an environment.mak -file in the build directory. This contains -all- configurable parameters -for all of the make files in all of the subdirectories. Changing one -of these parameters will have an immediate effect. The use of makefile.in -and configure substitutions across build makefiles is not used at all. - -Furthermore, the make system runs with a current directory equal to the -source directory regardless of the destination directory. This means -#include "" and #include <> work as expected and more importantly -running 'make' in the source directory will work as expected. The -environment variable or make parameter 'BUILD' sets the build directory. -It may be an absolute path or a path relative to the top level directory. -By default build-arch/ then build/ will be used with a fall back to ./ This -means you can get all the advantages of a build directory without having to -cd into it to edit your source code! - -The make system also performs dependency generation on the fly as the -compiler runs. This is extremely fast and accurate. There is however -one failure condition that occurs when a header file is erased. In -this case you should run make clean to purge the .o and .d files to -rebuild. - -The final significant deviation from normal make practices is -in how the build directory is managed. It is not nearly a mirror of -the source directory but is logically divided in the following manner - bin/ - methods/ - doc/ - examples/ - include/ - apt-pkg/ - obj/ - apt-pkg/ - cmdline/ - [...] -Only .o and .d files are placed in the obj/ subdirectory. The final compiled -binaries are placed in bin, published headers for inter-component linking -are placed in include/ and documentation is generated into doc/. This means -all runnable programs are within the bin/ directory, a huge benefit for -debugging inter-program relationships. The .so files are also placed in -bin/ for simplicity. - -By default make is put into silent mode. During operation there should be -no shell or compiler messages only status messages from the makefiles, -if any pop up that indicates there may be a problem with your environment. -For debugging you can disable this by setting NOISY=1, ala - make NOISY=1 - -Using the makefiles -~~~~~ ~~~ ~~~~~~~~~ -The makefiles for the components are really simple. The complexity is hidden -within the buildlib/ directory. Each makefile defines a set of make variables -for the bit it is going to make then includes a makefile fragment from -the buildlib/. This fragment generates the necessary rules based on the -originally defined variables. This process can be repeated as many times as -necessary for as many programs or libraries as are in the directory. - -Many of the make fragments have some useful properties involving sub -directories and other interesting features. They are more completely -described in the fragment code in buildlib. Some tips on writing fragments -are included in buildlib/defaults.mak - -The fragments are NEVER processed by configure, so if you make changes to -them they will have an immediate effect. - -Autoconf -~~~~~~~~ -Straight out of CVS you have to initialize autoconf. This requires -automake (I really don't know why) and autoconf and requires doing - aclocal -I buildlib - autoconf -[Alternatively you can run make startup in the top level build dir] - -Autoconf is configured to do some basic system probes for optional and -required functionality and generate an environment.mak and include/config.h -from it's findings. It will then write a 'makefile' and run make dirs to -create the output directory tree. - -It is not my belief that autoconf should be used to generate substantial -source code markup to escape OS problems. If an OS problem does crop up -it can likely be corrected by installing the correct files into the -build include/ dir and perhaps writing some replacement code and -linking it in. To the fullest extent possible the source code should conform -to standards and not cater to broken systems. - -Autoconf will also write a makefile into the top level of the build dir, -this simply acts as a wrapper to the main top level make in the source tree. -There is one big warning, you can't use both this make file and the -ones in the top level tree. Make is not able to resolve rules that -go to the same file through different paths and this will confuse the -depends mechanism. I recommend always using the makefiles in the -source directory and exporting BUILD. |