BUILDING(8) NetBSD System Manager's Manual BUILDING(8) NAME BUILDING - Procedure for building NetBSD from source code. STATUS This document is a work-in-progress. As such, the information described here may not match the reality of the build system as of this writing. Once this document is completely in sync with reality, this paragraph will be removed. Discrepancies between this documentation and the current reality of im- plementation are noted specially, as with the note below: Note: This document applies only to platforms which use the new toolchain as indicated by the default setting of TOOLCHAIN_MISSING in . Platforms which have not yet been switched to the new toolchain should continue building traditionally, using the notes specified in the file UPDATING. REQUIREMENTS NetBSD is designed to be buildable on most POSIX-compliant host systems. The basic build procedure is the same whether compiling natively (on the same NetBSD architecture) or cross compiling (on another architecture or OS). This source tree contains a special subtree, ``tools'', which uses the host system to create a build toolchain for the target architecture. The host system must have at least C and C++ compilers in order to create the toolchain (make is not required); all other tools are created as part of the NetBSD build process. Note: A couple of host toolchain components are not yet available in the tools directory. Also, some tools use non-POSIX, non-ANSI C extensions and need to be standardized. As a result, cross-compil- ing from systems other than NetBSD is not currently supported. FILES Source tree layout doc/BUILDING.mdoc This document (in -mdoc troff format; the original copy). BUILDING This document (in plaintext). Makefile The main Makefile for NetBSD; should only be run for na- tive builds with an appropriately up-to-date version of NetBSD make(1). (For building from out-of-date systems or on a non-native host, see the build.sh shell script.) UPDATING Special notes for updating from an earlier revision of NetBSD. It is important to read this file before every build of an updated source tree. build.sh Bourne-compatible shell script used for building the host build tools and the NetBSD system from scratch. Can be used for both native and cross builds, and should be used instead of make(1) for any source tree that is updated and recompiled regularly. crypto/dist/, dist/, gnu/dist/ Sources imported verbatim from third parties, without man- gling the existing build structure. Other source trees in bin through usr.sbin use the NetBSD make(1) ``reachover'' Makefile semantics when building these programs for a na- tive host. distrib/, etc/ Sources for items used when making a full release snap- shot, such as files installed in /etc on the destination system, boot media, and release notes. regress/ Regression test harness. Can be cross-compiled, but only run natively. sys/ NetBSD kernel sources. tools/ ``Reachover'' build structure for the host build tools. This has a special method of determining out-of-date sta- tus. bin/ ... usr.sbin/ Sources to the NetBSD userland (non-kernel) programs. If any of these directories are missing, they will be skipped during the build. Build tree layout The NetBSD build tree is described in hier(7), and the release layout is described in release(7). CONFIGURATION Environment variables Several environment variables control the behaviour of NetBSD builds. MACHINE Machine type. MACHINE_ARCH Machine architecture. MAKE Path name to invoke make(1) as. MAKEFLAGS Flags to invoke make(1) with. MAKEOBJDIR Directory to use as the .OBJDIR for the current direc- tory. Used only if MAKEOBJDIRPREFIX is not defined. MAKEOBJDIR can only be provided in the environment. MAKEOBJDIRPREFIX Top level directory of the object directory tree. If this is defined, ${MAKEOBJDIRPREFIX}/${.CURDIR} is used as the .OBJDIR for the current directory. The current directory may be read only. MAKEOBJDIRPREFIX can only be provided in the environment. "make" variables Several variables control the behavior of NetBSD builds. Unless other- wise specified, these variables may be set in either the process environ- ment or the make(1) configuration file specified by MAKECONF. BUILDID Identifier for the build. The identifier will be appended to object directory names, and can be consulted in the make(1) configuration file in order to set additional build parame- ters, such as compiler flags. DESTDIR Directory to contain the built NetBSD system. If set, spe- cial options are passed to the compilation tools to prevent their default use of the host system's /usr/include, /usr/lib, and so forth. This pathname should not end with a slash (/) character (for installation into the system's root directory, set DESTDIR to an empty string). The directory must reside on a file system which supports long file names and hard links. Default: Empty string if USETOOLS is ``yes''; unset other- wise. MAKECONF The name of the make(1) configuration file. Only settable in the process environment. Default: ``/etc/mk.conf'' MKCATPAGES Can be set to ``yes'' or ``no''. Indicates whether prefor- matted plaintext manual pages will be created during a build. Default: ``yes'' MKCRYPTO Can be set to ``yes'' or ``no''. Indicates whether crypto- graphic code will be included in a build; provided for the benefit of countries that do not allow strong cryptography. Will not affect use of the standard low-security password en- cryption system, crypt(3). Default: ``yes'' MKDOC Can be set to ``yes'' or ``no''. Indicates whether system documentation destined for /usr/share/doc will be installed during a build. Default: ``yes'' MKHOSTOBJ Can be set to ``yes'' or ``no''. If set to ``yes'', then for programs intended to be run on the compile host, the name, release, and architecture of the host operating system will be suffixed to the name of the object directory created by ``make obj''. (This allows multiple host systems to compile NetBSD for a single target.) If set to ``no'', then programs built to be run on the compile host will use the same object directory names as programs built to be run on the target. Default: ``no'' MKINFO Can be set to ``yes'' or ``no''. Indicates whether GNU Info files, used for the documentation for most of the compilation tools, will be created and installed during a build. Default: ``yes'' MKLINT Can be set to ``yes'' or ``no''. Indicates whether lint(1) will be run against portions of the NetBSD source code during the build, and whether lint libraries will be installed into /usr/libdata/lint. Default: ``yes'' MKMAN Can be set to ``yes'' or ``no''. Indicates whether manual pages will be installed during a build. Default: ``yes'' MKNLS Can be set to ``yes'' or ``no''. Indicates whether Native Language System locale zone files will be compiled and in- stalled during a build. Default: ``yes'' MKOBJ Can be set to ``yes'' or ``no''. Indicates whether object directories will be created when running ``make obj''. If set to ``no'', then all built files will be located inside the regular source tree. Default: ``yes'' MKPIC Can be set to ``yes'' or ``no''. Indicates whether shared objects and libraries will be created and installed during a build. If set to ``no'', the entire built system will be statically linked. Default: Platform dependent. As of this writing, all plat- forms except sh3 default to ``yes''. MKPICINSTALL Can be set to ``yes'' or ``no''. Indicates whether the ar(1) format libraries (lib*_pic.a), used to generate shared li- braries, are installed during a build. Default: ``yes'' MKPROFILE Can be set to ``yes'' or ``no''. Indicates whether profiled libraries (lib*_p.a) will be built and installed during a build. Default: ``yes''; however, some platforms turn off MKPROFILE by default at times due to toolchain problems with profiled code. MKSHARE Can be set to ``yes'' or ``no''. Indicates whether files destined to reside in /usr/share will be built and installed during a build. If set to ``no'', then all of MKCATPAGES, MKDOC, MKINFO, MKMAN, and MKNLS will be set to ``no'' uncon- ditionally. Default: ``yes'' TOOLDIR Directory to hold the host tools, once built. This directory should be unique to a given host system and NetBSD source tree. (However, multiple targets may share the same TOOLDIR; the target-dependent files have unique names.) If unset, a default based on the uname(1) information of the host plat- form will be created in the .OBJDIR of src/tools. Default: Unset. UNPRIVED If set, then an unprivileged install will occur. The user, group, permissions, and file flags, will not be set on the installed item; instead the information will be appended to a file called METALOG in DESTDIR. The contents of METALOG is used during the generation of the distribution tar files to ensure that the appropriate file ownership is stored. Default: Unset. UPDATE If set, then all install operations intended to write to DESTDIR will compare file timestamps before installing, and skip the install phase if the destination files are up-to- date. This also has implications on full builds (see next subsection). Default: Unset. USETOOLS Indicates whether the tools specified by TOOLDIR should be used as part of a build in progress. Must be set to ``yes'' if cross-compiling. yes Use the tools from TOOLDIR. no Do not use the tools from TOOLDIR, but refuse to build native compilation tool components that are version- specific for that tool. never Do not use the tools from TOOLDIR, even when building native tool components. This is similar to the tradi- tional NetBSD build method, but does not verify that the compilation tools in use are up-to-date enough in order to build the tree successfully. This may cause build or runtime problems when building the whole NetBSD source tree. Default: ``yes'' if building all or part of a whole NetBSD source tree (detected automatically); ``no'' otherwise (to preserve traditional semantics of the make(1) in- clude files). "make" variables for full builds These variables only affect the top level ``Makefile'' and do not affect manually building subtrees of the NetBSD source code. INSTALLWORLDDIR Location for the ``make installworld'' target to install to. Default: ``/'' MKOBJDIRS Can be set to ``yes'' or ``no''. Indicates whether ob- ject directories will be created automatically (via a ``make obj'' pass) at the start of a build. Default: ``yes'' NBUILDJOBS Now obsolete. Use the make(1) option -j, instead (see below) Default: Unset. NOCLEANDIR If set, avoids the ``make cleandir'' phase of a full build. This has the effect of allowing only changed files in a source tree to be recompiled. This can speed up builds when updating only a few files in the tree. Default: Unset. NODISTRIBDIRS If set, avoids the ``make distrib-dirs'' phase of a full build. This skips running mtree(8) on DESTDIR, useful on systems where building as an unprivileged user, or where it is known that the system-wide mtree files have not changed. Default: Unset. NOINCLUDES If set, avoids the ``make includes'' phase of a full build. This has the effect of preventing make(1) from thinking that some programs are out-of-date simply be- cause the system include files have changed. However, this option should not be used when updating the entire NetBSD source tree arbitrarily; it is suggested to use UPDATE in that case. Default: Unset. RELEASEDIR If set, specifies the directory to which a release(7) layout will be written at the end of a ``make release''. Default: Unset. UPDATE If set, then in addition to the effects described for UPDATE above, this implies the effects of NOCLEANDIR. BUILDING "make" command line options This is only a summary of options available to make(1); only the options used most frequently with NetBSD builds are listed here. -j njob Run up to njob make(1) subjobs in parallel. Makefiles should use .WAIT or have explicit dependancies as necessary to en- force build ordering. If you see build failures with -j, please save complete build logs so the failures can be ana- lyzed. -m dir Specify the default directory for searching for system Make- file segments, mainly the files. When building any full NetBSD source tree, this should be set to the ``share/mk'' directory in the source tree. (This is set auto- matically when building from the top level.) -n Display the commands that would have been executed, but do not actually execute them. This will still cause recursion to take place. -v var Print make(1)'s idea of the value of var. Does not build any targets. var=value Set the variable var to value, overriding any setting speci- fied by the process environment, the MAKECONF configuration file, or the system Makefile segments. "make" targets These default targets may be built by running make(1) in any subtree of the NetBSD source code. It is recommended that none of these be used from the top level Makefile; as a specific exception, ``make obj'' and ``make cleandir'' are useful in that context. all Build programs, libraries, and preformatted documentation. clean Remove program and library object code files. cleandir Same as clean, but also remove preformatted documentation, de- pendency files generated by ``make depend'', and any other files known to be created at build time. ``make distclean'' may be used as a synonym, for familiarity with a similar well- known convention. depend Create dependency files (.depend) containing more detailed in- formation about the dependencies of source code on header files. Allows programs to be recompiled automatically when a dependency changes. dependall Does a ``make depend'' immediately followed by a ``make all''. This improves cache locality of the build since both passes read the source files in their entirety. includes Build and install system header files. Typically needed be- fore any system libraries or programs can be built. install Install programs, libraries, and documentation into DESTDIR. Few files will be installed to /dev, /etc, /root or /var in order to prevent user supplied configuration data from being overwritten. lint Run lint(1) against the C source code, where appropriate, and generate system-installed lint libraries. obj Create object directories to be used for built files, instead of building directly in the source tree. tags Create ctags(1) searchable function lists usable by the ex(1) and vi(1) text editors. "make" targets for the top level Additional make(1) targets are usable specifically from the top source level to facilitate building the entire NetBSD source tree. build Build the entire NetBSD system. This orders portions of the source tree such that prerequisites will be built in the proper order. distribution Do a ``make build'', and then install a full distribution into DESTDIR, including files in /dev, /etc, /root and /var. buildworld As per ``make distribution'', except that it ensures that DESTDIR is not the root directory. installworld Install the distribution from DESTDIR to INSTALLWORLDDIR (which defaults to the root directory). Ensures that INSTALLWORLDDIR is the not root directory if cross compil- ing. Note: It is highly recommended that you upgrade your kernel and reboot before performing this operation. release Do a ``make distribution'', build kernels, distribution me- dia, and install sets, and then package the system into a standard release layout as described by release(7). This requires that RELEASEDIR be set (see above). regression-tests Can only be run after building the regression tests in the directory ``regress''. Runs the compiled regression tests on the local host. The "build.sh" script This script file is a Bourne shell script designed to build the entire NetBSD system on any host with a Bourne shell in /bin/sh, including many that are not POSIX compliant. Note that if a host system's /bin/sh is unusually old and broken, the Korn Shell (/bin/ksh), if available, may be a usable alternative. All cross-compile builds, and most native builds, of the entire system should make use of build.sh rather than just running ``make''. This way, the make(1) program will be bootstrapped properly, in case the host sys- tem has an older or incompatible ``make'' program. When compiling the entire system via build.sh, many make(1) variables are set for you in order to help encapsulate the build process. In the list of options below, variables that are automatically set by build.sh are noted where applicable. The following operations are supported by build.sh: build Build the system as per ``make build''. This option im- plies the obj and tools operations. distribution Build a full distribution as per ``make distribution''. This option implies the build operation. release Build a full release as per ``make release''. This option implies the distribution operation. makewrapper Create the nbmake-MACHINE wrapper. This operation is auto- matically performed for any of the other operations. obj Perform ``make obj''. tools Build and install the host tools from src/tools. kernel=kconf Build a new kernel. The kconf argument is the name of a configuration file suitable for use by config(8). If kconf does not contain any `/' characters, the configuration file is expected to be found in the KERNCONFDIR directory, which is typically sys/arch/MACHINE/conf. The new kernel will be built in a subdirectory of KERNOBJDIR, which is typically sys/arch/MACHINE/compile or an associated object directory. In order to ensure that the kernel is built using up-to- date tools, it is strongly recommended that the tools be rebuilt (using the tools operation). install=idir Install the contents of DESTDIR to idir, using ``make installworld''. The following command line options alter the behaviour of the above oper- ations: The following command line options alter the behaviour of the build.sh operations described above: -a arch Set the value of MACHINE_ARCH to arch. -B buildid Set the value of BUILDID to buildid. This will also append the build idenfitier to the name of the ``make'' wrapper script so that the resulting name is of the form ``nbmake-MACHINE- BUILDID''. -D dest Set the value of DESTDIR to dest. -E Set `expert' mode. This overrides various sanity checks, and allows: DESTDIR does not have to be set to a non-root path for builds, and UNPRIVED does not have to be set when building as a non-root user. Note: It is highly recommended that you know what you are doing when you use this option. -j njob Passed through to make(1). Makefiles should use .WAIT or have explicit dependancies as necessary to enforce build ordering. If you see build failures with -j, please save complete build logs so the failures can be analyzed. -M obj Set MAKEOBJDIRPREFIX to obj. -m mach Set the value of MACHINE to mach. This will also override any value of MACHINE_ARCH in the process environment with a value deduced from mach, unless -a is specified. All cross builds require -m, but if unset on a NetBSD host, the host's value of MACHINE will be detected and used automatically. -n Show the commands that would be executed by build.sh, but do not make any changes. This is similar in concept to ``make -n''. -O obj Create an appropriate transform macro for MAKEOBJDIR that will place the built object files under obj. For instance, a set- ting of /usr/obj will place build-time files under /usr/obj/bin, /usr/obj/lib, and so forth. -o Set the value of MKOBJDIRS to ``no''. -R rel Set the value of RELEASEDIR to rel. -r Remove the contents of DESTDIR and TOOLDIR before building (provides a clean starting point). This will skip deleting DESTDIR if building on a native system to the root directory. -T tools Set the value of TOOLDIR to tools. If set, the bootstrap ``make'' will only be rebuilt as needed (when the source files for make(1) change). -U Set the UNPRIVED variable. -u Set the UPDATE variable. -V var=[value] Set the variable var to value (which is optional). -w wrapper Create the nbmake wrapper script (see below) in a custom loca- tion, specified by wrapper. This allows, for instance, to place the wrapper in PATH automatically. Note that wrapper is the full name of the file, not just a directory name. The "nbmake-MACHINE" wrapper script If using the build.sh script to build NetBSD, a nbmake-MACHINE script will be created in TOOLDIR/bin upon the first build to assist in building subtrees on a cross-compile host. nbmake-MACHINE can be invoked in lieu of make(1), and will instead call the up-to-date version of ``nbmake'' installed into TOOLDIR/bin with sev- eral key variables pre-set, including MACHINE, MACHINE_ARCH, and TOOLDIR. This script can be symlinked into a directory listed in PATH, or called with an absolute path. EXAMPLES ./build.sh tools kernel=GENERIC Build a new toolchain, and use the new toolchain to configure and build a new GENERIC kernel. This is a simpler way to achieve what the first three examples do. ./build.sh -U -D /some/DESTDIR distribution Using unprivileged mode, build a complete distribution in /some/DESTDIR. # ./build.sh -U -D /some/DESTDIR installworld=/ As root, install the distribution that was built with unprivi- leged mode from /some/DESTDIR to /. (Even though this is run as root, -U is required so that the permissions stored in /some/DESTDIR/METALOG are correctly applied to the files as they're copied to /). ./build.sh -U -D /some/dir/DESTDIR -R /some/dir/RELEASE release Using unprivileged mode, build a complete release in /some/dir/RELEASE. OBSOLETE VARIABLES NBUILDJOBS Use the make(1) option -j, instead. USE_NEW_TOOLCHAIN The new toolchain is now the default. To disable, use TOOLCHAIN_MISSING=yes. SEE ALSO make(1), hier(7), release(7) HISTORY The build.sh based build scheme was introduced for NetBSD 1.6 as USE_NEW_TOOLCHAIN, and re-worked to TOOLCHAIN_MISSING after that. BUGS A few platforms are not yet using this build system. NetBSD January 26, 2003 10