BUILDING(8) System Manager's Manual BUILDING(8) NAME BUILDING - Procedure for building NetBSD from source code 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 the build.sh shell script which supports both native and cross builds of NetBSD. 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(1) is not required); all other tools (including make(1) as nbmake) are created as part of the NetBSD build process. (See the Environment variables section below if you need to override or manually select your compilers.) Note: Within this document, cross-references to manual pages are to the NetBSD manual pages, not the host system manual pages. The mdoc(7) source to the NetBSD manual pages can be found within the source tree, and these and can be formatted with mandoc(1) or nroff(1) if those are available on the host system. The NetBSD manual pages are also available at https://man.netbsd.org FILES Source tree layout BUILDING This document (in plaintext). Generated from doc/BUILDING.mdoc. Makefile The main Makefile for NetBSD; should only be run for native builds with an appropriately up-to-date version of NetBSD make(1). Intended for expert use with knowledge of its shortcomings, it has been superseded by the build.sh shell script as the recommended means for building NetBSD. 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instead of make(1) as it performs additional checks to prevent common issues going undetected, such as building with an outdated version of make(1). crypto/dist/, dist/, gnu/dist/ Sources imported verbatim from third parties, without mangling 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 native host. distrib/, etc/ Sources for items used when making a full release snapshot, such as files installed in DESTDIR/etc on the destination system, boot media, and release notes. doc/BUILDING.mdoc The source to this document, in mdoc(7) format. Used to generate BUILDING. external/, sys/external/ Sources and build infrastructure for components imported (mostly) unchanged from upstream maintainers, sorted by applicable license. This is (slowly) replacing the crypto/dist, dist, and gnu/dist directories. external/mit/xorg/ "Reachover" build structure for modular Xorg; the source is in X11SRCDIR. mk.conf Optional source tree specific mk.conf(5), used (if present) instead of /etc/mk.conf unless MAKECONF is defined. Note: Not part of the NetBSD source repository. regress/, tests/ Regression test harness. Can be cross-compiled, but only run natively. tests/ uses the atf(7) test framework; regress/ contains older tests that have not yet been migrated to atf(7). sys/ NetBSD kernel sources. tools/ "Reachover" build structure for the host build tools. This has a special method of determining out-of-date status. tools/compat/README Special notes for cross-hosting a NetBSD build on non- NetBSD platforms. Other directories including 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) (whose mdoc(7) source is in share/man/man7/hier.7), and the release layout is described in release(7) (whose mdoc(7) source is in share/man/man7/release.7). CONFIGURATION Environment variables Several environment variables control the behaviour of NetBSD builds. HOST_CC Path name to C compiler used to create the toolchain. Default: "cc". HOST_CFLAGS Flags passed to the host C compiler. Default: "-O". HOST_CPPFLAGS Flags passed to the host C/C++ pre-processor. Default: Unset. HOST_CXX Path name to C++ compiler used to create the toolchain. Default: Unset, but defaults to "c++" where required. HOST_CXXFLAGS Flags passed to the host C++ compiler. Default: Unset. HOST_SH Path name to a shell available on the host system and suitable for use during the build. The NetBSD build system requires a modern Bourne-like shell with POSIX- compliant features, and also requires support for the "local" keyword to declare local variables in shell functions (which is a widely-implemented but non- standardised feature). Depending on the host system, a suitable shell may be /bin/sh, /usr/xpg4/bin/sh, /bin/ksh (provided it is a variant of ksh that supports the "local" keyword, such as ksh88, but not ksh93), or /usr/local/bin/bash. Most parts of the build require HOST_SH to be an absolute path; however, build.sh allows it to be a simple command name, which will be converted to an absolute path by searching the PATH. Default: "sh". INSTALLBOOT_UBOOT_PATHS A colon-separated list of search paths used by installboot(8) to find U-Boot packages. Default: Unset. MACHINE Machine type, e.g., "macppc". Default: Unset. MACHINE_ARCH Machine architecture, e.g., "powerpc". Default: Unset. MAKE Path name to invoke make(1) as. Default: "make". MAKECONF The name of the make(1) configuration file. See make variables and mk.conf(5). Note: Only settable in the process environment. Default: "/etc/mk.conf", although build.sh will set the default to the full path to mk.conf if the latter is present in the same directory as build.sh. MAKEFLAGS Flags to invoke make(1) with. Note: build.sh ignores the value of MAKEFLAGS passed in the environment, but allows MAKEFLAGS to be set via the -V option. Default: "-X" on systems with a small ARG_MAX (Cygwin, Darwin, FreeBSD); otherwise unset. MAKEOBJDIR Directory to use as the .OBJDIR for the current directory. The value is subjected to variable expansion by make(1). Typical usage is to set this variable to a value involving the use of `${.CURDIR:S...}' or `${.CURDIR:C...}', to derive the value of .OBJDIR from the value of .CURDIR. Used only if MAKEOBJDIRPREFIX is not defined. Note: MAKEOBJDIR can be provided only in the environment or via the -O flag of build.sh; it cannot usefully be set inside a Makefile, including in mk.conf(5) or MAKECONF. Default: Unset. MAKEOBJDIRPREFIX Top level directory of the object directory tree. The value is subjected to variable expansion by make(1). build.sh will create the ${MAKEOBJDIRPREFIX} directory if necessary, but if make(1) is used without build.sh, then rules in will abort the build if the ${MAKEOBJDIRPREFIX} directory does not exist. If the value is defined and valid, then ${MAKEOBJDIRPREFIX}/${.CURDIR} is used as the .OBJDIR for the current directory. The current directory may be read only. Note: MAKEOBJDIRPREFIX can be provided only in the environment or via the -M flag of build.sh; it cannot usefully be set inside a Makefile, including in mk.conf(5) or MAKECONF. Default: Unset. TMPDIR Top-level directory to store temporary directories used by build.sh before paths to other directories such as .OBJDIR can be determined. Note: Must support execution of binaries. I.e., without mount(8)'s -o noexec option. Default: "/tmp". make variables Variables that control the behavior of NetBSD builds are documented in mk.conf(5) (whose mdoc(7) source is in share/man/man5/mk.conf.5). Unless otherwise specified, these variables may be set in either the process environment or the make(1) configuration file mk.conf(5) specified by MAKECONF. Note: Variables set in the environment, either directly or via build.sh options to set specific values in the nbmake-MACHINE wrapper script do not override variables set in the mk.conf(5) file. To allow variables in mk.conf(5) to be overridden by the environment or build.sh options, define the variables using the "?=" make(1) variable assignment operator. For example, MAKEVERBOSE?=1 The supported mk.conf(5) make variables are: BSDOBJDIR, BSDSRCDIR, BUILD, BUILDID, BUILDINFO, BUILDSEED, CDEXTRA, CONFIGOPTS, COPTS, CPUFLAGS, DESTDIR, EXTERNAL_TOOLCHAIN, INSTALLBOOT_BOARDS, INSTALLWORLDDIR, KERNARCHDIR, KERNCONFDIR, KERNEL_DIR, KERNOBJDIR, KERNSRCDIR, LOCALTIME, MAKEVERBOSE, MKAMDGPUFIRMWARE, MKARGON2, MKARZERO, MKATF, MKBINUTILS, MKBSDGREP, MKBSDTAR, MKCATPAGES, MKCLEANSRC, MKCLEANVERIFY, MKCOMPAT, MKCOMPATMODULES, MKCOMPATTESTS, MKCOMPATX11, MKCOMPLEX, MKCROSSGDB, MKCTF, MKCVS, MKCXX, MKDEBUG, MKDEBUGKERNEL, MKDEBUGLIB, MKDEBUGTOOLS, MKDEPINCLUDES, MKDOC, MKDTB, MKDTC, MKDTRACE, MKDYNAMICROOT, MKFIRMWARE, MKGCC, MKGCCCMDS, MKGDB, MKGROFF, MKGROFFHTMLDOC, MKHESIOD, MKHOSTOBJ, MKHTML, MKIEEEFP, MKINET6, MKINFO, MKIPFILTER, MKISCSI, MKKERBEROS, MKKMOD, MKKYUA, MKLDAP, MKLIBCSANITIZER, MKLIBCXX, MKLIBSTDCXX, MKLINKLIB, MKLINT, MKLLVM, MKLLVMRT, MKLVM, MKMAKEMANDB, MKMAN, MKMANDOC, MKMANZ, MKMDNS, MKNLS, MKNOUVEAUFIRMWARE, MKNPF, MKNSD, MKOBJ, MKOBJDIRS, MKPAM, MKPCC, MKPF, MKPIC, MKPICINSTALL, MKPICLIB, MKPIE, MKPIGZGZIP, MKPOSTFIX, MKPROFILE, MKRADEONFIRMWARE, MKRELRO, MKREPRO, MKREPRO_TIMESTAMP, MKRUMP, MKSANITIZER, MKSHARE, MKSKEY, MKSLJIT, MKSOFTFLOAT, MKSTATICLIB, MKSTATICPIE, MKSTRIPIDENT, MKSTRIPSYM, MKTEGRAFIRMWARE, MKTPM, MKUNBOUND, MKUNPRIVED, MKUPDATE, MKX11, MKX11FONTS, MKX11MOTIF, MKXORG_SERVER, MKYP, MKZFS, NETBSDSRCDIR, NETBSD_OFFICIAL_RELEASE, NOCLEANDIR, NODISTRIBDIRS, NOINCLUDES, OBJMACHINE, RELEASEDIR, RUMPUSER_THREADS, RUMP_CURLWP, RUMP_DEBUG, RUMP_DIAGNOSTIC, RUMP_KTRACE, RUMP_LOCKDEBUG, RUMP_LOCKS_UP, RUMP_NBCOMPAT, RUMP_VIRTIF, RUMP_VNODE_LOCKDEBUG, TOOLCHAIN_MISSING, TOOLDIR, USETOOLS, USE_FORT, USE_HESIOD, USE_INET6, USE_JEMALLOC, USE_KERBEROS, USE_LDAP, USE_LIBCSANITIZER, USE_PAM, USE_PIGZGZIP, USE_SANITIZER, USE_SKEY, USE_SSP, USE_XZ_SETS, USE_YP, X11MOTIFPATH, X11SRCDIR. The obsolete mk.conf(5) make variables are: EXTSRCSRCDIR, MKBFD, MKCRYPTO, MKEXTSRC, MKKDEBUG, MKKERBEROS4, MKLLD, MKLLDB, MKMCLINKER, MKPERFUSE, MKTOOLSDEBUG, NBUILDJOBS, SHAREDSTRINGS, USE_COMBINE, USE_NEW_TOOLCHAIN. BUILDING make command line options This is not a summary of all the 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 dependencies as necessary to enforce build ordering. -m dir Specify the default directory for searching for system Makefile 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 automatically when building from the top level, or when using build.sh. -n Show the commands that would have been executed, but do not actually execute them. This will still cause recursion to take place. -V var Show 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 specified 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, dependency files generated by "make depend", and any other files known to be created at build time. depend Create dependency files (.depend) containing more detailed information 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. distclean Synonym for cleandir. includes Build and install system header files. Typically needed before any system libraries or programs can be built. install Install programs, libraries, and documentation into DESTDIR. Few files will be installed to DESTDIR/dev, DESTDIR/etc, DESTDIR/root or DESTDIR/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 (except the kernel). 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 (which does not include a kernel) into DESTDIR, including files in DESTDIR/dev, DESTDIR/etc, DESTDIR/root and DESTDIR/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 not the root directory if cross compiling. The INSTALLSETS environment variable may be set to a space- separated list of distribution sets to be installed. By default, all sets except "etc" and "xetc" are installed, so most files in INSTALLWORLDDIR/etc will not be installed or modified. Note: Before performing this operation with INSTALLWORLDDIR=/, it is highly recommended that you upgrade your kernel and reboot. After performing this operation, it is recommended that you use etcupdate(8) to update files in INSTALLWORLDDIR/etc, and postinstall(8) to check for or fix inconsistencies. sets Create distribution sets from DESTDIR into RELEASEDIR/RELEASEMACHINEDIR/binary/sets. Should be run after "make distribution", as "make build" alone does not install all of the required files. sourcesets Create source sets of the source tree into RELEASEDIR/source/sets. syspkgs Create syspkgs from DESTDIR into RELEASEDIR/RELEASEMACHINEDIR/binary/syspkgs. Should be run after "make distribution", as "make build" alone does not install all of the required files. release Do a "make distribution", build kernels, distribution media, and install sets (this as per "make sets"), and then package the system into a standard release layout as described by release(7). This requires that RELEASEDIR be set (see above). iso-image Create a NetBSD installation CD-ROM image in the RELEASEDIR/images directory. The CD-ROM file system will have a layout as described in release(7). For most machine types, the CD-ROM will be bootable, and will automatically run the sysinst(8) menu-based installation program, which can be used to install or upgrade a NetBSD system. Bootable CD-ROMs also contain tools that may be useful in repairing a damaged NetBSD installation. Before "make iso-image" is attempted, RELEASEDIR must be populated by "make release" or equivalent. Note: Other, smaller, CD-ROM images may be created in the RELEASEDIR/RELEASEMACHINEDIR/installation/cdrom directory by "make release". These smaller images usually contain the same tools as the larger images in RELEASEDIR/images, but do not contain additional content such as the distribution sets. Note: The mac68k port still uses an older method of creating CD-ROM images. This requires the mkisofs(1) utility, which is not part of NetBSD, but which can be installed from pkgsrc/sysutils/cdrtools. iso-image-source Create a NetBSD installation CD-ROM image in the RELEASEDIR/images directory. The CD-ROM file system will have a layout as described in release(7). It will have top level directories for the machine type and source. For most machine types, the CD-ROM will be bootable, and will automatically run the sysinst(8) menu-based installation program, which can be used to install or upgrade a NetBSD system. Bootable CD-ROMs also contain tools that may be useful in repairing a damaged NetBSD installation. Before "make iso-image-source" is attempted, RELEASEDIR must be populated by "make sourcesets release" or equivalent. Note: Other, smaller, CD-ROM images may be created in the RELEASEDIR/RELEASEMACHINEDIR/installation/cdrom directory by "make release". These smaller images usually contain the same tools as the larger images in RELEASEDIR/images, but do not contain additional content such as the distribution sets. Note: The mac68k port still uses an older method of creating CD-ROM images. This requires the mkisofs(1) utility, which is not part of NetBSD, but which can be installed from pkgsrc/sysutils/cdrtools. install-image Create a bootable NetBSD installation disk image in the RELEASEDIR/images directory. The installation disk image is suitable for copying to bootable USB flash memory sticks, etc., for machines which are able to boot from such devices. The file system in the bootable disk image will have a layout as described in release(7). The installation image is bootable, and will automatically run the sysinst(8) menu-based installation program, which can be used to install or upgrade a NetBSD system. The image also contains tools that may be useful in repairing a damaged NetBSD installation. Before "make install-image" is attempted, RELEASEDIR must be populated by "make release" or equivalent. The build must have been performed with MKUNPRIVED=yes because "make install-image" relies on information in DESTDIR/METALOG. live-image Create NetBSD live images in the RELEASEDIR/images directory. The live image contains all necessary files to boot NetBSD up to multi-user mode, including all files which should be extracted during installation, NetBSD disklabel, bootloaders, etc. The live image is suitable for use as a disk image in virtual machine environments such as QEMU, and also useful to boot NetBSD from a USB flash memory stick on a real machine, without the need for installation. Before "make live-image" is attempted, RELEASEDIR must be populated by "make release" or equivalent. The build must have been performed with MKUNPRIVED=yes because "make install-image" relies on information in DESTDIR/METALOG. regression-tests Can only be run after building the regression tests in the directory "regress". Runs those compiled regression tests on the local host. Note: Most tests are now managed instead using atf(7); this target should probably run those as well but currently does not. The build.sh script This script file is a shell script designed to build the entire NetBSD system on any host with a suitable modern shell and some common utilities. The required shell features are described under the HOST_SH variable. If a host system's default shell does support the required features, then we suggest that you explicitly specify a suitable shell using a command like /path/to/suitable/shell build.sh [options] The above command will usually enable build.sh to automatically set HOST_SH=/path/to/suitable/shell, but if that fails, then the following set of commands may be used instead: HOST_SH=/path/to/suitable/shell export HOST_SH ${HOST_SH} build.sh [options] If build.sh detects that it is being executed under an unsuitable shell, it attempts to exec a suitable shell instead, or shows an error message. If HOST_SH is not set explicitly, then build.sh sets a default using heuristics dependent on the host platform, or from the shell under which build.sh is executed (if that can be determined), or using the first copy of sh found in PATH. 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 system 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". Before the main part of the build commences, this command runs the obj operation (unless the -o option is given), "make cleandir" (unless the -u option is given), and the tools operation. distribution Build a full distribution as per "make distribution". This command first runs the build operation. release Build a full release as per "make release". This command first runs the distribution operation. help Show a help message, and exit. makewrapper Create the nbmake-MACHINE wrapper script. This operation is automatically performed for any of the other operations. cleandir Perform "make cleandir". obj Perform "make obj". tools Build and install the host tools from src/tools. This command will first run "make obj" and "make cleandir" in the tools subdirectory unless the -o or -u options (respectively) are given. install=idir Install the contents of DESTDIR to idir, using "make installworld". Note: Files that are part of the "etc" or "xetc" sets will not be installed, unless overridden by the INSTALLSETS environment variable. kernel=kconf Build a new kernel. The kconf argument is the name of a configuration file suitable for use by config(1). 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. This command does not imply the tools command; run the tools command first unless it is certain that the tools already exist and are up to date. This command will run "make cleandir" on the kernel in question first unless the -u option is given. kernel.gdb=kconf Build a new kernel with debug information. Similar to the above kernel=kconf operation, but creates a netbsd.gdb file alongside of the kernel netbsd, which contains a full symbol table and can be used for debugging (for example with a cross-gdb built by MKCROSSGDB). kernels This command will build all kernels defined in port specific release build procedure. This command internally calls the kernel=kconf operation for each found kernel configuration file. modules This command will build kernel modules and install them into DESTDIR. releasekernel=kconf Install a gzip(1)ed copy of the kernel previously built by kernel=kconf into RELEASEDIR/RELEASEMACHINEDIR/binary/kernel, usually as netbsd-kconf.gz, although the "netbsd" prefix is determined from the "config" directives in kconf. sets Perform "make sets". sourcesets Perform "make sourcesets". syspkgs Perform "make syspkgs". iso-image Perform "make iso-image". iso-image-source Perform "make iso-image-source". install-image Perform "make install-image". live-image Perform "make live-image". list-arch Show a list of valid MACHINE and MACHINE_ARCH settings, the default MACHINE_ARCH for each MACHINE, and aliases for MACHINE/MACHINE_ARCH pairs, and then exits. The -m or -a options (or both) may be used to specify glob patterns that will be used to narrow the list of results; for example, "build.sh -m 'evb*' -a '*arm*' list-arch" will list all known MACHINE/MACHINE_ARCH values in which either MACHINE or ALIAS matches the pattern `evb*', and MACHINE_ARCH matches the pattern `*arm*'. 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. See the -m option for more information. -B buildid Set the value of BUILDID to buildid. This will also append the build identifier to the name of the nbmake-MACHINE wrapper script so that the resulting name is of the form "nbmake-MACHINE-BUILDID". -C cdextras Append cdextras to the CDEXTRA variable, which is a space- separated list of files or directories that will be added to the CD-ROM image that may be create by the "iso-image" or "iso-image-source" operations. Files will be added to the root of the CD-ROM image, whereas directories will be copied recursively. If relative paths are specified, they will be converted to absolute paths before being used. Multiple paths may be specified via multiple -C options, or via a single option whose argument contains multiple space-separated paths. -c compiler Select the compiler for the toolchain to build NetBSD and for inclusion in the NetBSD distribution. Supported choices: clang gcc [default] The compiler used to build the toolchain can be different; see HOST_CC and HOST_CXX. -D dest Set the value of DESTDIR to dest. If a relative path is specified, it will be converted to an absolute path before being used. -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 MKUNPRIVED=yes 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. -h Show a help message, and exit. -j njob Run up to njob make(1) subjobs in parallel; passed through to make(1). If you see failures for reasons other than running out of memory while using build.sh with -j, please save complete build logs so the failures can be analyzed. To achieve the fastest builds, -j values between (1 + the number of CPUs) and (2 * the number of CPUs) are recommended. Use lower values on machines with limited memory or I/O bandwidth. -M obj Set MAKEOBJDIRPREFIX to obj. Unsets MAKEOBJDIR. See "-O obj" for more information. For instance, if the source directory is /usr/src, a setting of "-M /usr/obj" will place build-time files under /usr/obj/usr/src/bin, /usr/obj/usr/src/lib, /usr/obj/usr/src/usr.bin, and so forth. If a relative path is specified, it will be converted to an absolute path before being used. build.sh imposes the restriction that the argument to the -M option must not begin with a "$" (dollar sign) character; otherwise it would be too difficult to determine whether the value is an absolute or a relative path. If the directory does not already exist, build.sh will create it. -m mach Set the value of MACHINE to mach, unless the mach argument is an alias that refers to a MACHINE/MACHINE_ARCH pair, in which case both MACHINE and MACHINE_ARCH are set from the alias. Such aliases are interpreted entirely by build.sh; they are not used by any other part of the build system. The MACHINE_ARCH setting implied by mach will override any value of MACHINE_ARCH in the process environment, but will not override a value set by the -a option. All cross builds require -m, but if unset on a NetBSD host, the host's value of MACHINE will be detected and used automatically. See the list-arch operation for a way to get a list of valid MACHINE and MACHINE_ARCH settings. -N noiselevel Set the "noisiness" level of the build, by setting MAKEVERBOSE to noiselevel. -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. Unsets MAKEOBJDIRPREFIX. For instance, a setting of "-O /usr/obj" will place build-time files under /usr/obj/bin, /usr/obj/lib, /usr/obj/usr.bin, and so forth. If a relative path is specified, it will be converted to an absolute path before being used. build.sh imposes the restriction that the argument to the -O option must not contain a "$" (dollar sign) character. If the directory does not already exist, build.sh will create it. In normal use, exactly one of the -M or -O options should be specified. If neither -M nor -O is specified, then a default object directory will be chosen according to rules in . Relying on this default is not recommended because it is determined by complex rules that are influenced by the values of several variables and by the location of the source directory. Note: Placing the obj directory location outside of the default source tree hierarchy makes it easier to manually clear out old files in the event the "make cleandir" operation is unable to do so. (See CAVEATS below.) Note: The use of one of -M or -O is the only means of building multiple machine architecture userlands from the same source tree without cleaning between builds (in which case, one would specify distinct obj locations for each). -o Set the value of MKOBJDIRS to "no". Otherwise, it will be automatically set to "yes". This default is opposite to the behaviour when not using build.sh. -P Set the value of MKREPRO and MKREPRO_TIMESTAMP to the latest source CVS timestamp for reproducible builds. -R rel Set the value of RELEASEDIR to rel. If a relative path is specified, it will be converted to an absolute path before being used. -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. -S seed Change the value of BUILDSEED to seed. This should rarely be necessary. -T tools Set the value of TOOLDIR to tools. If a relative path is specified, it will be converted to an absolute path before being used. If set, the bootstrap "make" will only be rebuilt if the source files for make(1) have changed. -U Set MKUNPRIVED=yes. -u Set MKUPDATE=yes. -V var=[value] Set the environment variable var to an optional value. This is propagated to the nbmake-MACHINE wrapper script. -w wrapper Create the nbmake-MACHINE wrapper script (see below) in a custom location, specified by wrapper. This allows, for instance, to place the wrapper script in PATH automatically. Note: wrapper is the full name of the file, not just a directory name. If a relative path is specified, it will be converted to an absolute path before being used. -X x11src Set the value of X11SRCDIR to x11src. If a relative path is specified, it will be converted to an absolute path before being used. -x Set MKX11=yes. -Z var Unset ("zap") the environment variable var. This is propagated to the nbmake-MACHINE wrapper script. -? Show a help message, and exit. The nbmake-MACHINE wrapper script If using the build.sh script to build NetBSD, a nbmake-MACHINE wrapper script will be created in TOOLDIR/bin upon the first build to assist in building subtrees on a cross-compile host. The nbmake-MACHINE wrapper script can be invoked in lieu of make(1), and will instead call the up-to-date version of "nbmake" installed into TOOLDIR/bin with several key variables pre-set, including MACHINE, MACHINE_ARCH, and TOOLDIR. nbmake-MACHINE will also set variables specified with -V, and unset variables specified with -Z. Note that by default these variables will not override mk.conf(5); see make variables for more details. This wrapper script can be symlinked into a directory listed in PATH, or called with an absolute path. EXAMPLES 1. % ./build.sh [OPTIONS] tools kernel=GENERIC Build a new toolchain, and use the new toolchain to configure and build a new GENERIC kernel. 2. % ./build.sh [OPTIONS] -U distribution Using unprivileged mode, build a complete distribution to a DESTDIR directory that build.sh selects (and will show). 3. # ./build.sh [OPTIONS] -U install=/ As root, install to / the distribution that was built by example 2. Even though this is run as root, -U is required so that the permissions stored in DESTDIR/METALOG are correctly applied to the files as they're copied to /. 4. % ./build.sh [OPTIONS] -U -u release Using unprivileged mode, build a complete release to DESTDIR and RELEASEDIR directories that build.sh selects (and will show). MKUPDATE=yes (-u) is set to prevent the "make cleandir", so that if this is run after example 2, it doesn't need to redo that portion of the release build. SEE ALSO config(1), ctags(1), ex(1), gzip(1), lint(1), make(1), mandoc(1), mkisofs(1), nroff(1), vi(1), mk.conf(5), atf(7), hier(7), mdoc(7), release(7), etcupdate(8), installboot(8), mount(8), postinstall(8), sysinst(8), pkgsrc/sysutils/cdrtools Note: The NetBSD manual pages are also available at https://man.netbsd.org 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. CAVEATS After significant updates to third-party components in the source tree, the "make cleandir" operation may be insufficient to clean out old files in object directories. Instead, one may have to manually remove the files. Consult the UPDATING file for notices concerning this. NetBSD July 21, 2023 NetBSD