Copyright (C) 2009 Peter Breitenlohner You may freely use, modify and/or distribute this file. Layout of the TeX Live (TL) build system ======================================== The TL 2009 build system has been completely restructured, using Autoconf, Automake, and Libtool. The main purpose was to configure and build each library before configuring any module (program or other library) depending on that library. This allows to check for properties and features of a library built as part of the TL tree in much the same way as for an installed (system) version of that library. This should simplify upgrading of modules maintained independently and/or integrating new modules into the TL build system. 1. Layout of directories ======================== 1.1. Overall layout ------------------- texk/kpathsea/* the Kpathsea library libs/*/* various other libraries texk/*/* programs (mostly using Kpathsea) utils/*/* utility programs (not using Kpathsea) texk/am/* Makefile.am fragments texk/web2c/am/* for the Kpathsea library texk/web2c/*/am/* and the Web2C programs libs/Lib/* library Lib (zlib, libpng, t1lib, etc.) texk/Prog/* program package Prog (web2c, afm2pl, bibtex8, etc.) utils/Util/* utility program package Util (dialog, pdfopen, ps2eps, etc.) libs/dummy/* dummy modules texk/dummy/* used to configure utils/dummy/* the real modules ac/* various configure.ac fragments (configure options) */ac/* for the whole TL tree */*/ac/* or for a particular component build-aux/* auxiliary build scripts (config.guess etc.) m4/kpse-pkgs.m4 Autoconf macros defining the lists of Lib, Prog, and Util modules and handling loops over these lists m4/* other Autoconf macros 1.2. A library `Lib' -------------------- libs/Lib/ac/withenable.ac defines libraries required by Lib libs/Lib/ac/Lib.ac defines basic tests for a system version of Lib m4/kpse-Lib-flags.m4 defines Autoconf macros for configure options as well as KPSE_LIB_FLAGS, to be used in configure.ac files and defining Make variables Several libraries use an (almost) unmodified source tree supplemented by a proxy build system (bypassing that of the source tree), e.g., libs/zlib/zlib-1.2.3/* (almost) unmodified source tree libs/zlib/Makefile.am proxy Makefile.am libs/zlib/configure.ac and configure.ac 1.3. A program `Prog' --------------------- texk/Prog/ac/withenable.ac defines libraries required by Prog, provides the configure option --disable-Prog texk/Prog/ac/Prog.ac optionally defines Prog specific configure option that should be seen at the top-level 1.4. A utility program `Util' ----------------------------- utils/Util/ac/withenable.ac defines libraries required by Util, provides the configure option --disable-Util 2. Running `configure' ====================== Running 'configure' for the top-level directory will in addition configure the directories texk/kpathsea/, libs/, libs/dummy/, utils/, utils/dummy, texk/, and texk/dummy/. This will determine the programs (utils/Util/ and texk/Prog) to be built and libraries from the TL tree (texk/kpathsea/ and libs/Lib) required by these programs. 3. Running `make' ================= Running 'make' in the top-level directory will recurse into the directories texk/kpathsea/, libs/, utils/, and texk/. 3.1. Running `make' in libs/ ---------------------------- First, for each subdirectory libs/Lib not yet configured, this runs `configure' and if required `make all' in that directory. Then this recurses into all required subdirectories for the selected Make target: `default' or `all' to (re-)build, `check' to run tests, `install' etc. 3.2. Running `make' in utils/ and texk/ --------------------------------------- Quite similarly, for each subdirectory utils/Util and texk/Prog not yet configured, this first runs `configure' and if required `make all' in that directory. Subsequently, this recurses into all required subdirectories to (re-)build, run tests, install, etc. 3.3 Parallel builds ------------------- The TL build system allows for parallel builds ('make -j n' with n>1), carefully formulating Make rules when a tool (such as 'tangle' or 'convert') creates several output files. This can considerably speed up a TL build on multi core systems. I usually use 'make -j 4 -l 8.0'; please report any failures. 3.4 Using a Configure Cache File -------------------------------- Further speed up of a TL build can be achieved by using a configure cache file, e.g., running 'configure -C' at the top-level. This should work after some initial problem have been fixed; please report any failures. 3.5 Comments ------------ 3.5.1 Comment 1 --------------- After successfully running 'make' from the top-level, as second 'make' should not have to rebuild anything. When configure scripts have been modified, it may take several iterations of 'make' (only in in tekx/web2c/) until everything has stabilized. This is a problem that still needs investigation, but I believe that after the first iteration everything is up to date, except for some bad timestamps. 3.5.2 Comment 2 --------------- If running 'make' from the top-level fails in a subdirectory libs/*/, utils/*/, or /texk/*/ you can remove that directory from the build tree, fix the problem, and once again run 'make' from the top-level. 3.5.3 Comment 3 --------------- The build system allows to successfully run 'make dist' and 'make distcheck' (at least on my {i686,x86_64}-linux-gnu systems), producing tarballs tex-live-2009-MM-DD.tar.{bz2,gz} from which everything can be (re-)built; please keep it that way! 3.5.4 Comment 4 --------------- The process described above configures all directories, even for libraries and programs not to be built. This is necessary for Make targets such as `dist' or `distcheck' that have to recurse into all subdirectories, whereas normal targets such as `all', `check', or `install' only recurse into the required subdirectories. As a side effect, if building in utils/Util/ or texk/Prog/ has been disabled, the Makefile in that directory still contains all the rules to build everything. Thus running 'make' and 'make install' in that subdirectory will build and install everything, unless some configure tests have failed because required libraries from the TL tree where missing when that subdirectory has been configured. Similarly, when, e.g., building e-TeX has been disabled (as by default), you can run 'make etex' (or 'make etex.exe') in the subdirectory texk/web2c/ to build e-TeX (although there is no simple way to have e-TeX installed). 4. Extending the TL build system ================================ 4.1 Adding a new program directory ---------------------------------- To add a new program directory utils/Util (not using Kpathsea) or texk/Prog (possibly using Kpathsea) you first have to add the directory Util to the M4 list kpse_utils_pkgs or Prog to the M4 list kpse_texk_pkgs defined in m4/kpse-pkgs.m4. In addition you must create a configure.ac fragment utils/Util/ac/witheanble.ac or texk/Prog/ac/witheanble.ac defining any required libraries from the TL tree and whether this new program is to be built by default (in the absence of the corresponding '--enable-Util/Prog' or '--disable-Util/Prog' configure options). If a program texk/Prog requires specific configure options to be seen at the top-level, they should be defined in an additional configure.ac fragment texk/Prog/ac/Prog.ac included from texk/Prog/ac/withenable.ac and texk/Prog/configure.ac (as, e.g., for texk/web2c/ and texk/xdvik/). 4.2 Adding a new library directory ---------------------------------- To add a new library directory libs/Lib you first have to add the directory Lib to the M4 list kpse_libs_pkgs defined in m4/kpse-pkgs.m4. In addition you must create a configure.ac fragment libs/Lib/ac/witheanble.ac defining any required libraries from the TL tree and whether an installed (system) version of this library can be used. If that is the case, another configure.ac fragment libs/Lib/ac/Lib.ac must define (AC_CHECK_FUNCS and AC_CHECK_HEADERS) tests for a system version to be acceptable. Finally you must create a file m4/kpse-Lib-flags.m4 defining the M4 macro KPSE_LIB_FLAGS (where 'LIB' is a sanitized uppercase version of 'Lib') setting up the Make variables LIB_INCLUDES, LIB_LIBS, and LIB_DEPEND with the required values for CPPFLAGS, LDADD, and dependencies, as well as LIB_RULE with a (multiline) Make rule to rebuild that library when necessary. If a system version of the library can be used, another M4 macro KPSE_LIB_SYSTEM_FLAGS in m4/kpse-Lib-flags.m4 must define values for LIB_INCLUDES and LIB_LIBS, depending on values for the configure options '--with-Lib-includes' and/or '--with-Lib-libdir', and you must add the line 'AC_REQUIRE([KPSE_LIB_SYSTEM_FLAGS])' to the definition of the M4 macro KPSE_ALL_SYSTEM_FLAGS in m4/kpse-pkgs.m4. 5. Updating the TL build system =============================== When anything in the TL build system (configure.ac and Makefile.am files with their fragments or M4 macros in m4/) has been modified you have to rebuild the coresponding configure, Makefile.in, and config.h or c-auto,h files. This is most easily done automatically using maintainer-mode. Due to some dependencies known to Makefile but not recognized by Aclocal it may, however, happen that Aclocal is run again and agin, keeping the aclocal.m4 files unmodified. This can be fixed by touch {,libs/texk/,utils/}aclocal.m4 from the top-level. The files in the SVN repository are all up to date, but some of them may be rebuilt when using maintainer-mode due to their relative timestamps. This will eventually be fixed, once everything has stabilized. Alternatively, you can run the 'reautoconf' script from the top-level (yet to be done). The 'config.guess', 'config.sub', etc. files for most packages are now kept centrally in build-aux/. There are, however, independent copies in, e.g., libs/freetype/freetype-1.5/, libs/freetype2/freetype-2.3.8/builds/unix/, and similar places that might need updating (not done automatically by the 'reautoconf' script).