xref: /freebsd/share/man/man7/build.7 (revision 535af610)
1.\" Copyright (c) 2000
2.\"	Mike W. Meyer
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25.\" $FreeBSD$
26.\"
27.Dd August 1, 2023
28.Dt BUILD 7
29.Os
30.Sh NAME
31.Nm build
32.Nd General instructions on how to build the system
33.Sh DESCRIPTION
34The sources for the
35.Fx
36system and its applications are contained in three different directories,
37normally
38.Pa /usr/src ,
39.Pa /usr/doc ,
40and
41.Pa /usr/ports .
42These directories may be initially empty or non-existent until updated with
43Git
44.Po installed from packages with
45.Xr pkg 7
46or from
47.Xr ports 7 Pc .
48Directory
49.Pa /usr/src
50contains the
51.Dq "base system"
52sources, which is loosely defined as the things required to rebuild
53the system to a useful state.
54Directory
55.Pa /usr/doc
56contains the source for the system documentation, excluding the manual
57pages.
58Directory
59.Pa /usr/ports
60contains a tree that provides a consistent interface for building and
61installing third party applications.
62For more information about the ports build process, see
63.Xr ports 7 .
64.Pp
65The
66.Xr make 1
67command is used in each of these directories to build and install the
68things in that directory.
69Issuing the
70.Xr make 1
71command in any directory issues the
72.Xr make 1
73command recursively in all subdirectories.
74With no target specified, the items in the directories are built
75and no further action is taken.
76.Pp
77A source tree is allowed to be read-only.
78As described in
79.Xr make 1 ,
80objects are usually built in a separate object directory hierarchy
81specified by the environment variable
82.Va MAKEOBJDIRPREFIX ,
83or under
84.Pa /usr/obj
85if variable
86.Va MAKEOBJDIRPREFIX
87is not set.
88The canonical object directory is described in the documentation for the
89.Cm buildworld
90target below.
91.Pp
92The build may be controlled by defining
93.Xr make 1
94variables described in the
95.Sx ENVIRONMENT
96section below, and by the variables documented in
97.Xr make.conf 5 .
98.Pp
99The default components included in the build are specified in the file
100.Pa /etc/src.conf
101in the source tree.
102To override the default file, include the SRCCONF option in the make steps,
103pointing to a custom src.conf file.
104For more information see
105.Xr src.conf 5 .
106.Pp
107The following list provides the names and actions for the targets
108supported by the build system:
109.Bl -tag -width ".Cm cleandepend"
110.It Cm analyze
111Run Clang static analyzer against all objects and present output on stdout.
112.It Cm check
113Run tests for a given subdirectory.
114The default directory used is
115.Pa ${.OBJDIR} ,
116but the check directory can be changed with
117.Pa ${CHECKDIR} .
118.It Cm checkworld
119Run the
120.Fx
121test suite on installed world.
122.It Cm clean
123Remove any files created during the build process.
124.It Cm cleandepend
125Remove the
126.Pa ${.OBJDIR}/${DEPENDFILE}*
127files generated by prior
128.Dq Li "make"
129and
130.Dq Li "make depend"
131steps.
132.It Cm cleandir
133Remove the canonical object directory if it exists, or perform
134actions equivalent to
135.Dq Li "make clean cleandepend"
136if it does not.
137This target will also remove an
138.Pa obj
139link in
140.Pa ${.CURDIR}
141if that exists.
142.Pp
143It is advisable to run
144.Dq Li "make cleandir"
145twice: the first invocation will remove the canonical object directory
146and the second one will clean up
147.Pa ${.CURDIR} .
148.It Cm depend
149Generate a list of build dependencies in file
150.Pa ${.OBJDIR}/${DEPENDFILE} .
151Per-object dependencies are generated at build time and stored in
152.Pa ${.OBJDIR}/${DEPENDFILE}.${OBJ} .
153.It Cm install
154Install the results of the build to the appropriate location in the
155installation directory hierarchy specified in variable
156.Va DESTDIR .
157.It Cm obj
158Create the canonical object directory associated with the current
159directory.
160.It Cm objlink
161Create a symbolic link to the canonical object directory in
162.Pa ${.CURDIR} .
163.It Cm tags
164Generate a tags file using the program specified in the
165.Xr make 1
166variable
167.Va CTAGS .
168The build system supports
169.Xr ctags 1
170and
171.Nm "GNU Global" .
172.El
173.Pp
174The other supported targets under directory
175.Pa /usr/src
176are:
177.Bl -tag -width ".Cm distributeworld"
178.It Cm buildenv
179Spawn an interactive shell with environment variables set up for
180building the system or individual components.
181For cross-building the target architecture needs to be specified with
182.Xr make 1
183variables
184.Va TARGET_ARCH
185and
186.Va TARGET .
187.Pp
188This target is only useful after a complete toolchain (including
189the compiler, linker, assembler, headers and libraries) has been
190built; see the
191.Cm toolchain
192target below.
193.It Cm buildworld
194Build everything but the kernel, configure files in
195.Pa etc ,
196and
197.Pa release .
198The object directory can be changed from the default
199.Pa /usr/obj
200by setting the
201.Pa MAKEOBJDIRPREFIX
202.Xr make 1
203variable.
204The actual build location prefix used
205depends on the
206.Va WITH_UNIFIED_OBJDIR
207option from
208.Xr src.conf 5 .
209If enabled it is
210.Pa ${MAKEOBJDIRPREFIX}${.CURDIR}/${TARGET}.${TARGET_ARCH}
211for all builds.
212If disabled it is
213.Pa ${MAKEOBJDIRPREFIX}${.CURDIR}
214for native builds, and
215.Pa ${MAKEOBJDIRPREFIX}/${TARGET}.${TARGET_ARCH}${.CURDIR}
216for cross builds and native builds with variable
217.Va CROSS_BUILD_TESTING
218set.
219.It Cm cleankernel
220Attempts to clean up targets built by a preceding
221.Cm buildkernel ,
222or similar step, built from the same source directory and
223.Va KERNCONF .
224.It Cm cleanworld
225Attempt to clean up targets built by a preceding
226.Cm buildworld ,
227or similar step, built from this source directory.
228.It Cm cleanuniverse
229When
230.Va WITH_UNIFIED_OBJDIR
231is enabled, attempt to clean up targets built by a preceding
232.Cm buildworld ,
233.Cm universe ,
234or similar step, for any architecture built from this source directory.
235.It Cm distributeworld
236Distribute everything compiled by a preceding
237.Cm buildworld
238step.
239Files are placed in the directory hierarchy specified by
240.Xr make 1
241variable
242.Va DISTDIR .
243This target is used while building a release; see
244.Xr release 7 .
245.It Cm native-xtools
246This target builds a cross-toolchain for the given
247.Sy TARGET
248and
249.Sy TARGET_ARCH ,
250as well as a select list of static userland tools for the host system.
251This is intended to be used in a jail where QEMU is used to improve
252performance by avoiding emulating binaries that do not need to be emulated.
253.Sy TARGET
254and
255.Sy TARGET_ARCH
256should be defined.
257.It Cm native-xtools-install
258Installs the results to
259.Pa ${DESTDIR}/${NXTP}
260where
261.Va NXTP
262defaults to
263.Pa nxb-bin .
264.Sy TARGET
265and
266.Sy TARGET_ARCH
267must be defined.
268.It Cm packageworld
269Archive the results of
270.Cm distributeworld ,
271placing the results in
272.Va DISTDIR .
273This target is used while building a release; see
274.Xr release 7 .
275.It Cm installworld
276Install everything built by a preceding
277.Cm buildworld
278step into the directory hierarchy pointed to by
279.Xr make 1
280variable
281.Va DESTDIR .
282.Pp
283If installing onto an NFS file system and running
284.Xr make 1
285with the
286.Fl j
287option, make sure that
288.Xr rpc.lockd 8
289is running on both client and server.
290See
291.Xr rc.conf 5
292on how to make it start at boot time.
293.It Cm toolchain
294Create the build toolchain needed to build the rest of the system.
295For cross-architecture builds, this step creates a cross-toolchain.
296.It Cm universe
297For each architecture,
298execute a
299.Cm buildworld
300followed by a
301.Cm buildkernel
302for all kernels for that architecture,
303including
304.Pa LINT .
305This command takes a long time.
306.It Cm kernels
307Like
308.Cm universe
309with
310.Va WITHOUT_WORLDS
311defined so only the kernels for each architecture are built.
312.It Cm worlds
313Like
314.Cm universe
315with
316.Va WITHOUT_KERNELS
317defined so only the worlds for each architecture are built.
318.It Cm targets
319Print a list of supported
320.Va TARGET
321/
322.Va TARGET_ARCH
323pairs for world and kernel targets.
324.It Cm tinderbox
325Execute the same targets as
326.Cm universe .
327In addition print a summary of all failed targets at the end and
328exit with an error if there were any.
329.It Cm toolchains
330Create a build toolchain for each architecture supported by the build system.
331.It Cm xdev
332Builds and installs a cross-toolchain and sysroot for the given
333.Sy TARGET
334and
335.Sy TARGET_ARCH .
336The sysroot contains target library and headers.
337The target is an alias for
338.Cm xdev-build
339and
340.Cm xdev-install .
341The location of the files installed can be controlled with
342.Va DESTDIR .
343The target location in
344.Va DESTDIR
345is
346.Pa ${DESTDIR}/${XDTP}
347where
348.Va XDTP
349defaults to
350.Pa /usr/${XDDIR}
351and
352.Va XDDIR
353defaults to
354.Pa ${TARGET_ARCH}-freebsd .
355.It Cm xdev-build
356Builds for the
357.Cm xdev
358target.
359.It Cm xdev-install
360Installs the files for the
361.Cm xdev
362target.
363.It Cm xdev-links
364Installs autoconf-style symlinks to
365.Pa ${DESTDIR}/usr/bin
366pointing into the xdev toolchain in
367.Pa ${DESTDIR}/${XDTP} .
368.El
369.Pp
370Kernel specific build targets in
371.Pa /usr/src
372are:
373.Bl -tag -width ".Cm distributekernel"
374.It Cm buildkernel
375Rebuild the kernel and the kernel modules.
376The object directory can be changed from the default
377.Pa /usr/obj
378by setting the
379.Pa MAKEOBJDIRPREFIX
380.Xr make 1
381variable.
382.It Cm installkernel
383Install the kernel and the kernel modules to directory
384.Pa ${DESTDIR}/boot/kernel ,
385renaming any pre-existing directory with this name to
386.Pa kernel.old
387if it contained the currently running kernel.
388The target directory under
389.Pa ${DESTDIR}
390may be modified using the
391.Va INSTKERNNAME
392and
393.Va KODIR
394.Xr make 1
395variables.
396.It Cm distributekernel
397Install the kernel to the directory
398.Pa ${DISTDIR}/kernel/boot/kernel .
399This target is used while building a release; see
400.Xr release 7 .
401.It Cm packagekernel
402Archive the results of
403.Cm distributekernel ,
404placing the results in
405.Va DISTDIR .
406This target is used while building a release; see
407.Xr release 7 .
408.It Cm kernel
409Equivalent to
410.Cm buildkernel
411followed by
412.Cm installkernel
413.It Cm kernel-toolchain
414Rebuild the tools needed for kernel compilation.
415Use this if you did not do a
416.Cm buildworld
417first.
418.It Cm reinstallkernel
419Reinstall the kernel and the kernel modules, overwriting the contents
420of the target directory.
421As with the
422.Cm installkernel
423target, the target directory can be specified using the
424.Xr make 1
425variable
426.Va INSTKERNNAME .
427.El
428.Pp
429Convenience targets for cleaning up the install destination directory
430denoted by variable
431.Va DESTDIR
432include:
433.Bl -tag -width ".Cm delete-old-libs"
434.It Cm check-old
435Print a list of old files and directories in the system.
436.It Cm delete-old
437Delete obsolete base system files and directories interactively.
438When
439.Li -DBATCH_DELETE_OLD_FILES
440is specified at the command line, the delete operation will be
441non-interactive.
442The variables
443.Va DESTDIR ,
444.Va TARGET_ARCH
445and
446.Va TARGET
447should be set as with
448.Dq Li "make installworld" .
449.It Cm delete-old-libs
450Delete obsolete base system libraries interactively.
451This target should only be used if no third party software uses these
452libraries.
453When
454.Li -DBATCH_DELETE_OLD_FILES
455is specified at the command line, the delete operation will be
456non-interactive.
457The variables
458.Va DESTDIR ,
459.Va TARGET_ARCH
460and
461.Va TARGET
462should be set as with
463.Dq Li "make installworld" .
464.El
465.Sh ENVIRONMENT
466Variables that influence all builds include:
467.Bl -tag -width ".Va MAKEOBJDIRPREFIX"
468.It Va DEBUG_FLAGS
469Defines a set of debugging flags that will be used to build all userland
470binaries under
471.Pa /usr/src .
472When
473.Va DEBUG_FLAGS
474is defined, the
475.Cm install
476and
477.Cm installworld
478targets install binaries from the current
479.Va MAKEOBJDIRPREFIX
480without stripping,
481so that debugging information is retained in the installed binaries.
482.It Va DESTDIR
483The directory hierarchy prefix where built objects will be installed.
484If not set,
485.Va DESTDIR
486defaults to the empty string.
487.It Va MAKEOBJDIRPREFIX
488Defines the prefix for directory names in the tree of built objects.
489Defaults to
490.Pa /usr/obj
491if not defined.
492This variable should only be set in the environment or
493.Pa /etc/src-env.conf
494and not via
495.Pa /etc/make.conf
496or
497.Pa /etc/src.conf
498or the command line.
499.It Va WITHOUT_WERROR
500If defined, compiler warnings will not cause the build to halt,
501even if the makefile says otherwise.
502.It Va WITH_CTF
503If defined, the build process will run the DTrace CTF conversion
504tools on built objects.
505.El
506.Pp
507Additionally, builds in
508.Pa /usr/src
509are influenced by the following
510.Xr make 1
511variables:
512.Bl -tag -width ".Va LOCAL_MODULES_DIR"
513.It Va CROSS_TOOLCHAIN
514Requests use of an external toolchain to build either the world or kernel.
515This value of this variable can either be the full path to a file,
516or the base name of a file in
517.Pa ${LOCALBASE}/share/toolchains .
518The file should be a make file which sets variables to request an external
519toolchain such as
520.Va XCC .
521.Pp
522External toolchains are available in ports for both LLVM and GCC/binutils.
523For external toolchains available in ports,
524.Va CROSS_TOOLCHAIN
525should be set to the name of the package.
526LLVM toolchain packages use the name llvm<major version>.
527GCC toolchains provide separate packages for each architecture and use the
528name ${MACHINE_ARCH}-gcc<major version>.
529.It Va KERNCONF
530Overrides which kernel to build and install for the various kernel
531make targets.
532It defaults to
533.Cm GENERIC .
534.It Va KERNCONFDIR
535Overrides the directory in which
536.Va KERNCONF
537and any files included by
538.Va KERNCONF
539should be found.
540Defaults to
541.Pa sys/${ARCH}/conf .
542.It Va KERNFAST
543If set, the build target
544.Cm buildkernel
545defaults to setting
546.Va NO_KERNELCLEAN ,
547.Va NO_KERNELCONFIG ,
548and
549.Va NO_KERNELOBJ .
550When set to a value other than
551.Cm 1
552then
553.Va KERNCONF
554is set to the value of
555.Va KERNFAST .
556.It Va LOCAL_DIRS
557If set, this variable supplies a list of additional directories relative to
558the root of the source tree to build as part of the
559.Cm everything
560target.
561The directories are built in parallel with each other,
562and with the base system directories.
563Insert a
564.Va .WAIT
565directive at the beginning of the
566.Va LOCAL_DIRS
567list to ensure all base system directories are built first.
568.Va .WAIT
569may also be used as needed elsewhere within the list.
570.It Va LOCAL_ITOOLS
571If set, this variable supplies a list of additional tools that are used by the
572.Cm installworld
573and
574.Cm distributeworld
575targets.
576.It Va LOCAL_LIB_DIRS
577If set, this variable supplies a list of additional directories relative to
578the root of the source tree to build as part of the
579.Cm libraries
580target.
581The directories are built in parallel with each other,
582and with the base system libraries.
583Insert a
584.Va .WAIT
585directive at the beginning of the
586.Va LOCAL_DIRS
587list to ensure all base system libraries are built first.
588.Va .WAIT
589may also be used as needed elsewhere within the list.
590.It Va LOCAL_MTREE
591If set, this variable supplies a list of additional mtrees relative to the
592root of the source tree to use as part of the
593.Cm hierarchy
594target.
595.It Va LOCAL_LEGACY_DIRS
596If set, this variable supplies a list of additional directories relative to
597the root of the source tree to build as part of the
598.Cm legacy
599target.
600.It Va LOCAL_BSTOOL_DIRS
601If set, this variable supplies a list of additional directories relative to
602the root of the source tree to build as part of the
603.Cm bootstrap-tools
604target.
605.It Va LOCAL_TOOL_DIRS
606If set, this variable supplies a list of additional directories relative to
607the root of the source tree to build as part of the
608.Cm build-tools
609target.
610.It Va LOCAL_XTOOL_DIRS
611If set, this variable supplies a list of additional directories relative to
612the root of the source tree to build as part of the
613.Cm cross-tools
614target.
615.It Va PORTS_MODULES
616A list of ports with kernel modules that should be built and installed
617as part of the
618.Cm buildkernel
619and
620.Cm installkernel
621process.
622.Bd -literal -offset indent
623make PORTS_MODULES=emulators/virtualbox-ose-kmod kernel
624.Ed
625.It Va LOCAL_MODULES
626A list of external kernel modules that should be built and installed
627as part of the
628.Cm buildkernel
629and
630.Cm installkernel
631process.
632Defaults to the list of sub-directories of
633.Va LOCAL_MODULES_DIR .
634.It Va LOCAL_MODULES_DIR
635The directory in which to search for the kernel modules specified by
636.Va LOCAL_MODULES .
637Each kernel module should consist of a directory containing a makefile.
638Defaults to
639.Pa ${LOCALBASE}/sys/modules .
640.It Va SRCCONF
641Specify a file to override the default
642.Pa /etc/src.conf .
643The src.conf file controls the components to build.
644See
645.Xr src.conf 5
646.It Va STRIPBIN
647Command to use at install time when stripping binaries.
648Be sure to add any additional tools required to run
649.Va STRIPBIN
650to the
651.Va LOCAL_ITOOLS
652.Xr make 1
653variable before running the
654.Cm distributeworld
655or
656.Cm installworld
657targets.
658See
659.Xr install 1
660for more details.
661.It Va SUBDIR_OVERRIDE
662Override the default list of sub-directories and only build the
663sub-directory named in this variable.
664If combined with
665.Cm buildworld
666then all libraries and includes, and some of the build tools will still build
667as well.
668Specifying
669.Cm -DNO_LIBS ,
670and
671.Cm -DWORLDFAST
672will only build the specified directory as was done historically.
673When combined with
674.Cm buildworld
675it is necesarry to override
676.Va LOCAL_LIB_DIRS
677with any custom directories containing libraries.
678This allows building a subset of the system in the same way as
679.Cm buildworld
680does using its sysroot handling.
681This variable can also be useful when debugging failed builds.
682.Bd -literal -offset indent
683make some-target SUBDIR_OVERRIDE=foo/bar
684.Ed
685.It Va SYSDIR
686Specify the location of the kernel source to override the default
687.Pa /usr/src/sys .
688The kernel source is located in the
689.Pa sys
690subdirectory of the source tree checked out from the
691.Pa src.git
692repository.
693.It Va TARGET
694The target hardware platform.
695This is analogous to the
696.Dq Nm uname Fl m
697output.
698This is necessary to cross-build some target architectures.
699For example, cross-building for ARM64 machines requires
700.Va TARGET_ARCH Ns = Ns Li aarch64
701and
702.Va TARGET Ns = Ns Li arm64 .
703If not set,
704.Va TARGET
705defaults to the current hardware platform, unless
706.Va TARGET_ARCH
707is also set, in which case it defaults to the appropriate
708value for that architecture.
709.It Va TARGET_ARCH
710The target machine processor architecture.
711This is analogous to the
712.Dq Nm uname Fl p
713output.
714Set this to cross-build for a different architecture.
715If not set,
716.Va TARGET_ARCH
717defaults to the current machine architecture, unless
718.Va TARGET
719is also set, in which case it defaults to the appropriate
720value for that platform.
721Typically, one only needs to set
722.Va TARGET .
723.El
724.Pp
725Builds under directory
726.Pa /usr/src
727are also influenced by defining one or more of the following symbols,
728using the
729.Fl D
730option of
731.Xr make 1 :
732.Bl -tag -width ".Va LOADER_DEFAULT_INTERP"
733.It Va LOADER_DEFAULT_INTERP
734Defines what interpreter the default loader program will have.
735Valid values include
736.Dq 4th ,
737.Dq lua ,
738and
739.Dq simp .
740This creates the default link for
741.Pa /boot/loader
742to the loader with that interpreter.
743It also determines what interpreter is compiled into
744.Pa userboot .
745.It Va NO_CLEANDIR
746If set, the build targets that clean parts of the object tree use the
747equivalent of
748.Dq make clean
749instead of
750.Dq make cleandir .
751.It Va NO_CLEAN
752If set, no object tree files are cleaned at all.
753This is the default when
754.Va WITH_META_MODE
755is used with
756.Xr filemon 4
757loaded.
758See
759.Xr src.conf 5
760for more details.
761Setting
762.Va NO_CLEAN
763implies
764.Va NO_KERNELCLEAN ,
765so when
766.Va NO_CLEAN
767is set no kernel objects are cleaned either.
768.It Va NO_CTF
769If set, the build process does not run the DTrace CTF conversion tools
770on built objects.
771.It Va NO_SHARE
772If set, the build does not descend into the
773.Pa /usr/src/share
774subdirectory (i.e., manual pages, locale data files, timezone data files and
775other
776.Pa /usr/src/share
777files will not be rebuild from their sources).
778.It Va NO_KERNELCLEAN
779If set, the build process does not run
780.Dq make clean
781as part of the
782.Cm buildkernel
783target.
784.It Va NO_KERNELCONFIG
785If set, the build process does not run
786.Xr config 8
787as part of the
788.Cm buildkernel
789target.
790.It Va NO_KERNELOBJ
791If set, the build process does not run
792.Dq make obj
793as part of the
794.Cm buildkernel
795target.
796.It Va NO_LIBS
797If set, the libraries phase will be skipped.
798.It Va NO_OBJWALK
799If set, no object directories will be created.
800This should only be used if object directories were created in a
801previous build and no new directories are connected.
802.It Va UNIVERSE_TOOLCHAIN
803Requests use of the toolchain built as part of the
804.Cm universe
805target as an external toolchain.
806.It Va WORLDFAST
807If set, the build target
808.Cm buildworld
809defaults to setting
810.Va NO_CLEAN ,
811.Va NO_OBJWALK ,
812and will skip most bootstrap phases.
813It will only bootstrap libraries and build all of userland.
814This option should be used only when it is known that none of the bootstrap
815needs changed and that no new directories have been connected to the build.
816.El
817.Pp
818Builds under directory
819.Pa /usr/doc
820are influenced by the following
821.Xr make 1
822variables:
823.Bl -tag -width ".Va DOC_LANG"
824.It Va DOC_LANG
825If set, restricts the documentation build to the language subdirectories
826specified as its content.
827The default action is to build documentation for all languages.
828.El
829.Pp
830Builds using the
831.Cm universe
832and related targets are influenced by the following
833.Xr make 1
834variables:
835.Bl -tag -width ".Va USE_GCC_TOOLCHAINS"
836.It Va JFLAG
837Pass the value of this variable to each
838.Xr make 1
839invocation used to build worlds and kernels.
840This can be used to enable multiple jobs within a single architecture's build
841while still building each architecture serially.
842.It Va MAKE_JUST_KERNELS
843Only build kernels for each supported architecture.
844.It Va MAKE_JUST_WORLDS
845Only build worlds for each supported architecture.
846.It Va WITHOUT_WORLDS
847Only build kernels for each supported architecture.
848.It Va WITHOUT_KERNELS
849Only build worlds for each supported architecture.
850.It Va UNIVERSE_TARGET
851Execute the specified
852.Xr make 1
853target for each supported architecture instead of the default action of
854building a world and one or more kernels.
855This variable implies
856.Va WITHOUT_KERNELS .
857.It Va USE_GCC_TOOLCHAINS
858Use external GCC toolchains to build the requested targets.
859If the required toolchain package for a supported architecture is not installed,
860the build for that architecture is skipped.
861.It Va TARGETS
862Only build the listed targets instead of each supported architecture.
863.It Va EXTRA_TARGETS
864In addition to the supported architectures, build the semi-supported
865architectures.
866A semi-supported architecture has build support in the
867.Fx
868tree, but receives significantly less testing and is generally for
869fringe uses that do not have a wide appeal.
870.El
871.Sh FILES
872.Bl -tag -width ".Pa /usr/share/examples/etc/make.conf" -compact
873.It Pa /usr/doc/Makefile
874.It Pa /usr/doc/share/mk/doc.project.mk
875.It Pa /usr/ports/Mk/bsd.port.mk
876.It Pa /usr/ports/Mk/bsd.sites.mk
877.It Pa /usr/share/examples/etc/make.conf
878.It Pa /usr/src/Makefile
879.It Pa /usr/src/Makefile.inc1
880.El
881.Sh EXAMPLES
882For an
883.Dq approved
884method of updating your system from the latest sources, please see the
885.Sx COMMON ITEMS
886section in
887.Pa src/UPDATING .
888.Pp
889The following sequence of commands can be used to cross-build the
890system for the armv6 architecture on an amd64 host:
891.Bd -literal -offset indent
892cd /usr/src
893make TARGET_ARCH=armv6 buildworld buildkernel
894make TARGET_ARCH=armv6 DESTDIR=/clients/arm installworld installkernel
895.Ed
896.Sh HISTORY
897The
898.Nm
899manpage first appeared in
900.Fx 4.3 .
901.Sh SEE ALSO
902.Xr cc 1 ,
903.Xr install 1 ,
904.Xr make 1 ,
905.Xr make.conf 5 ,
906.Xr src.conf 5 ,
907.Xr arch 7 ,
908.Xr pkg 7 ,
909.Xr ports 7 ,
910.Xr release 7 ,
911.Xr tests 7 ,
912.Xr config 8 ,
913.Xr etcupdate 8 ,
914.Xr reboot 8 ,
915.Xr shutdown 8
916.Sh AUTHORS
917.An Mike W. Meyer Aq Mt mwm@mired.org
918