xref: /freebsd-13-stable/share/man/man7/build.7 (revision 60b9e2fac13ad381518acd253dd33a680dc7a0c8)
1.\" Copyright (c) 2000
2.\"	Mike W. Meyer
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25.\" $FreeBSD$
26.\"
27.Dd November 30, 2024
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 cleanworld
220Attempt to clean up targets built by a preceding
221.Cm buildworld ,
222or similar step built from this source directory.
223.It Cm cleanuniverse
224When
225.Va WITH_UNIFIED_OBJDIR
226is enabled, attempt to clean up targets built by a preceding
227.Cm buildworld ,
228.Cm universe ,
229or similar step, for any architecture built from this source directory.
230.It Cm distributeworld
231Distribute everything compiled by a preceding
232.Cm buildworld
233step.
234Files are placed in the directory hierarchy specified by
235.Xr make 1
236variable
237.Va DISTDIR .
238This target is used while building a release; see
239.Xr release 7 .
240.It Cm native-xtools
241This target builds a cross-toolchain for the given
242.Sy TARGET
243and
244.Sy TARGET_ARCH ,
245as well as a select list of static userland tools for the host system.
246This is intended to be used in a jail where QEMU is used to improve
247performance by avoiding emulating binaries that do not need to be emulated.
248.Sy TARGET
249and
250.Sy TARGET_ARCH
251should be defined.
252.It Cm native-xtools-install
253Installs the results to
254.Pa ${DESTDIR}/${NXTP}
255where
256.Va NXTP
257defaults to
258.Pa nxb-bin .
259.Sy TARGET
260and
261.Sy TARGET_ARCH
262must be defined.
263.It Cm packageworld
264Archive the results of
265.Cm distributeworld ,
266placing the results in
267.Va DISTDIR .
268This target is used while building a release; see
269.Xr release 7 .
270.It Cm installworld
271Install everything built by a preceding
272.Cm buildworld
273step into the directory hierarchy pointed to by
274.Xr make 1
275variable
276.Va DESTDIR .
277.Pp
278If installing onto an NFS file system and running
279.Xr make 1
280with the
281.Fl j
282option, make sure that
283.Xr rpc.lockd 8
284is running on both client and server.
285See
286.Xr rc.conf 5
287on how to make it start at boot time.
288.It Cm toolchain
289Create the build toolchain needed to build the rest of the system.
290For cross-architecture builds, this step creates a cross-toolchain.
291.It Cm universe
292For each architecture,
293execute a
294.Cm buildworld
295followed by a
296.Cm buildkernel
297for all kernels for that architecture,
298including
299.Pa LINT .
300This command takes a long time.
301.It Cm kernels
302Like
303.Cm universe
304with
305.Va WITHOUT_WORLDS
306defined so only the kernels for each architecture are built.
307.It Cm worlds
308Like
309.Cm universe
310with
311.Va WITHOUT_KERNELS
312defined so only the worlds for each architecture are built.
313.It Cm targets
314Print a list of supported
315.Va TARGET
316/
317.Va TARGET_ARCH
318pairs for world and kernel targets.
319.It Cm tinderbox
320Execute the same targets as
321.Cm universe .
322In addition print a summary of all failed targets at the end and
323exit with an error if there were any.
324.It Cm toolchains
325Create a build toolchain for each architecture supported by the build system.
326.It Cm xdev
327Builds and installs a cross-toolchain and sysroot for the given
328.Sy TARGET
329and
330.Sy TARGET_ARCH .
331The sysroot contains target library and headers.
332The target is an alias for
333.Cm xdev-build
334and
335.Cm xdev-install .
336The location of the files installed can be controlled with
337.Va DESTDIR .
338The target location in
339.Va DESTDIR
340is
341.Pa ${DESTDIR}/${XDTP}
342where
343.Va XDTP
344defaults to
345.Pa /usr/${XDDIR}
346and
347.Va XDDIR
348defaults to
349.Pa ${TARGET_ARCH}-freebsd .
350.It Cm xdev-build
351Builds for the
352.Cm xdev
353target.
354.It Cm xdev-install
355Installs the files for the
356.Cm xdev
357target.
358.It Cm xdev-links
359Installs autoconf-style symlinks to
360.Pa ${DESTDIR}/usr/bin
361pointing into the xdev toolchain in
362.Pa ${DESTDIR}/${XDTP} .
363.El
364.Pp
365Kernel specific build targets in
366.Pa /usr/src
367are:
368.Bl -tag -width ".Cm distributekernel"
369.It Cm buildkernel
370Rebuild the kernel and the kernel modules.
371The object directory can be changed from the default
372.Pa /usr/obj
373by setting the
374.Pa MAKEOBJDIRPREFIX
375.Xr make 1
376variable.
377.It Cm installkernel
378Install the kernel and the kernel modules to directory
379.Pa ${DESTDIR}/boot/kernel ,
380renaming any pre-existing directory with this name to
381.Pa kernel.old
382if it contained the currently running kernel.
383The target directory under
384.Pa ${DESTDIR}
385may be modified using the
386.Va INSTKERNNAME
387and
388.Va KODIR
389.Xr make 1
390variables.
391.It Cm distributekernel
392Install the kernel to the directory
393.Pa ${DISTDIR}/kernel/boot/kernel .
394This target is used while building a release; see
395.Xr release 7 .
396.It Cm packagekernel
397Archive the results of
398.Cm distributekernel ,
399placing the results in
400.Va DISTDIR .
401This target is used while building a release; see
402.Xr release 7 .
403.It Cm kernel
404Equivalent to
405.Cm buildkernel
406followed by
407.Cm installkernel
408.It Cm kernel-toolchain
409Rebuild the tools needed for kernel compilation.
410Use this if you did not do a
411.Cm buildworld
412first.
413.It Cm reinstallkernel
414Reinstall the kernel and the kernel modules, overwriting the contents
415of the target directory.
416As with the
417.Cm installkernel
418target, the target directory can be specified using the
419.Xr make 1
420variable
421.Va INSTKERNNAME .
422.El
423.Pp
424Convenience targets for cleaning up the install destination directory
425denoted by variable
426.Va DESTDIR
427include:
428.Bl -tag -width ".Cm delete-old-libs"
429.It Cm check-old
430Print a list of old files and directories in the system.
431.It Cm delete-old
432Delete obsolete base system files and directories interactively.
433When
434.Li -DBATCH_DELETE_OLD_FILES
435is specified at the command line, the delete operation will be
436non-interactive.
437The variables
438.Va DESTDIR ,
439.Va TARGET_ARCH
440and
441.Va TARGET
442should be set as with
443.Dq Li "make installworld" .
444.It Cm delete-old-libs
445Delete obsolete base system libraries interactively.
446This target should only be used if no third party software uses these
447libraries.
448When
449.Li -DBATCH_DELETE_OLD_FILES
450is specified at the command line, the delete operation will be
451non-interactive.
452The variables
453.Va DESTDIR ,
454.Va TARGET_ARCH
455and
456.Va TARGET
457should be set as with
458.Dq Li "make installworld" .
459.El
460.Sh ENVIRONMENT
461Variables that influence all builds include:
462.Bl -tag -width ".Va MAKEOBJDIRPREFIX"
463.It Va DEBUG_FLAGS
464Defines a set of debugging flags that will be used to build all userland
465binaries under
466.Pa /usr/src .
467When
468.Va DEBUG_FLAGS
469is defined, the
470.Cm install
471and
472.Cm installworld
473targets install binaries from the current
474.Va MAKEOBJDIRPREFIX
475without stripping,
476so that debugging information is retained in the installed binaries.
477.It Va DESTDIR
478The directory hierarchy prefix where built objects will be installed.
479If not set,
480.Va DESTDIR
481defaults to the empty string.
482If set,
483.Va DESTDIR
484must specify an absolute path.
485.It Va MAKEOBJDIRPREFIX
486Defines the prefix for directory names in the tree of built objects.
487Defaults to
488.Pa /usr/obj
489if not defined.
490This variable should only be set in the environment or
491.Pa /etc/src-env.conf
492and not via
493.Pa /etc/make.conf
494or
495.Pa /etc/src.conf
496or the command line.
497.Va MAKEOBJDIRPREFIX
498must specify an absolute path.
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 TARGET
686The target hardware platform.
687This is analogous to the
688.Dq Nm uname Fl m
689output.
690This is necessary to cross-build some target architectures.
691For example, cross-building for ARM64 machines requires
692.Va TARGET_ARCH Ns = Ns Li aarch64
693and
694.Va TARGET Ns = Ns Li arm64 .
695If not set,
696.Va TARGET
697defaults to the current hardware platform, unless
698.Va TARGET_ARCH
699is also set, in which case it defaults to the appropriate
700value for that architecture.
701.It Va TARGET_ARCH
702The target machine processor architecture.
703This is analogous to the
704.Dq Nm uname Fl p
705output.
706Set this to cross-build for a different architecture.
707If not set,
708.Va TARGET_ARCH
709defaults to the current machine architecture, unless
710.Va TARGET
711is also set, in which case it defaults to the appropriate
712value for that platform.
713Typically, one only needs to set
714.Va TARGET .
715.El
716.Pp
717Builds under directory
718.Pa /usr/src
719are also influenced by defining one or more of the following symbols,
720using the
721.Fl D
722option of
723.Xr make 1 :
724.Bl -tag -width ".Va LOADER_DEFAULT_INTERP"
725.It Va LOADER_DEFAULT_INTERP
726Defines what interpreter the default loader program will have.
727Valid values include
728.Dq 4th ,
729.Dq lua ,
730and
731.Dq simp .
732This creates the default link for
733.Pa /boot/loader
734to the loader with that interpreter.
735It also determines what interpreter is compiled into
736.Pa userboot .
737.It Va NO_CLEANDIR
738If set, the build targets that clean parts of the object tree use the
739equivalent of
740.Dq make clean
741instead of
742.Dq make cleandir .
743.It Va NO_CLEAN
744If set, no object tree files are cleaned at all.
745This is the default when
746.Va WITH_META_MODE
747is used with
748.Xr filemon 4
749loaded.
750See
751.Xr src.conf 5
752for more details.
753Setting
754.Va NO_CLEAN
755implies
756.Va NO_KERNELCLEAN ,
757so when
758.Va NO_CLEAN
759is set no kernel objects are cleaned either.
760.It Va NO_CTF
761If set, the build process does not run the DTrace CTF conversion tools
762on built objects.
763.It Va NO_SHARE
764If set, the build does not descend into the
765.Pa /usr/src/share
766subdirectory (i.e., manual pages, locale data files, timezone data files and
767other
768.Pa /usr/src/share
769files will not be rebuild from their sources).
770.It Va NO_KERNELCLEAN
771If set, the build process does not run
772.Dq make clean
773as part of the
774.Cm buildkernel
775target.
776.It Va NO_KERNELCONFIG
777If set, the build process does not run
778.Xr config 8
779as part of the
780.Cm buildkernel
781target.
782.It Va NO_KERNELOBJ
783If set, the build process does not run
784.Dq make obj
785as part of the
786.Cm buildkernel
787target.
788.It Va NO_LIBS
789If set, the libraries phase will be skipped.
790.It Va NO_OBJWALK
791If set, no object directories will be created.
792This should only be used if object directories were created in a
793previous build and no new directories are connected.
794.It Va UNIVERSE_TOOLCHAIN
795Requests use of the toolchain built as part of the
796.Cm universe
797target as an external toolchain.
798.It Va WORLDFAST
799If set, the build target
800.Cm buildworld
801defaults to setting
802.Va NO_CLEAN ,
803.Va NO_OBJWALK ,
804and will skip most bootstrap phases.
805It will only bootstrap libraries and build all of userland.
806This option should be used only when it is known that none of the bootstrap
807needs changed and that no new directories have been connected to the build.
808.El
809.Pp
810Builds under directory
811.Pa /usr/doc
812are influenced by the following
813.Xr make 1
814variables:
815.Bl -tag -width ".Va DOC_LANG"
816.It Va DOC_LANG
817If set, restricts the documentation build to the language subdirectories
818specified as its content.
819The default action is to build documentation for all languages.
820.El
821.Pp
822Builds using the
823.Cm universe
824and related targets are influenced by the following
825.Xr make 1
826variables:
827.Bl -tag -width ".Va USE_GCC_TOOLCHAINS"
828.It Va JFLAG
829Pass the value of this variable to each
830.Xr make 1
831invocation used to build worlds and kernels.
832This can be used to enable multiple jobs within a single architecture's build
833while still building each architecture serially.
834.It Va MAKE_JUST_KERNELS
835Only build kernels for each supported architecture.
836.It Va MAKE_JUST_WORLDS
837Only build worlds for each supported architecture.
838.It Va WITHOUT_WORLDS
839Only build kernels for each supported architecture.
840.It Va WITHOUT_KERNELS
841Only build worlds for each supported architecture.
842.It Va UNIVERSE_TARGET
843Execute the specified
844.Xr make 1
845target for each supported architecture instead of the default action of
846building a world and one or more kernels.
847This variable implies
848.Va WITHOUT_KERNELS .
849.It Va USE_GCC_TOOLCHAINS
850Use external GCC toolchains to build the requested targets.
851If the required toolchain package for a supported architecture is not installed,
852the build for that architecture is skipped.
853.It Va TARGETS
854Only build the listed targets instead of each supported architecture.
855.It Va EXTRA_TARGETS
856In addition to the supported architectures, build the semi-supported
857architectures.
858A semi-supported architecture has build support in the
859.Fx
860tree, but receives significantly less testing and is generally for
861fringe uses that do not have a wide appeal.
862.El
863.Sh FILES
864.Bl -tag -width ".Pa /usr/share/examples/etc/make.conf" -compact
865.It Pa /usr/doc/Makefile
866.It Pa /usr/doc/share/mk/doc.project.mk
867.It Pa /usr/ports/Mk/bsd.port.mk
868.It Pa /usr/ports/Mk/bsd.sites.mk
869.It Pa /usr/share/examples/etc/make.conf
870.It Pa /usr/src/Makefile
871.It Pa /usr/src/Makefile.inc1
872.El
873.Sh EXAMPLES
874For an
875.Dq approved
876method of updating your system from the latest sources, please see the
877.Sx COMMON ITEMS
878section in
879.Pa src/UPDATING .
880.Pp
881The following sequence of commands can be used to cross-build the
882system for the armv6 architecture on an amd64 host:
883.Bd -literal -offset indent
884cd /usr/src
885make TARGET_ARCH=armv6 buildworld buildkernel
886make TARGET_ARCH=armv6 DESTDIR=/clients/arm installworld installkernel
887.Ed
888.Sh HISTORY
889The
890.Nm
891manpage first appeared in
892.Fx 4.3 .
893.Sh SEE ALSO
894.Xr cc 1 ,
895.Xr install 1 ,
896.Xr make 1 ,
897.Xr make.conf 5 ,
898.Xr src.conf 5 ,
899.Xr arch 7 ,
900.Xr pkg 7 ,
901.Xr ports 7 ,
902.Xr release 7 ,
903.Xr tests 7 ,
904.Xr config 8 ,
905.Xr etcupdate 8 ,
906.Xr mergemaster 8 ,
907.Xr reboot 8 ,
908.Xr shutdown 8
909.Sh AUTHORS
910.An Mike W. Meyer Aq Mt mwm@mired.org
911