BUILDING revision 1.163 1 BUILDING(8) System Manager's Manual BUILDING(8)
2
3 NAME
4 BUILDING - Procedure for building NetBSD from source code
5
6 REQUIREMENTS
7 NetBSD is designed to be buildable on most POSIX-compliant host systems.
8 The basic build procedure is the same whether compiling natively (on the
9 same NetBSD architecture) or cross compiling (on another architecture or
10 OS).
11
12 This source tree contains the build.sh shell script which supports both
13 native and cross builds of NetBSD.
14
15 This source tree contains a special subtree, "tools", which uses the host
16 system to create a build toolchain for the target architecture. The host
17 system must have at least C and C++ compilers in order to create the
18 toolchain (make(1) is not required); all other tools (including make(1)
19 as nbmake) are created as part of the NetBSD build process. (See the
20 Environment variables section below if you need to override or manually
21 select your compilers.)
22
23 Note: Within this document, cross-references to manual pages are to the
24 NetBSD manual pages, not the host system manual pages. The mdoc(7)
25 source to the NetBSD manual pages can be found within the source tree,
26 and these and can be formatted with mandoc(1) or nroff(1) if those are
27 available on the host system. The NetBSD manual pages are also available
28 at https://man.netbsd.org
29
30 FILES
31 Source tree layout
32 BUILDING This document (in plaintext). Generated from
33 doc/BUILDING.mdoc.
34
35 Makefile The main Makefile for NetBSD; should only be run for
36 native builds with an appropriately up-to-date version of
37 NetBSD make(1). Intended for expert use with knowledge of
38 its shortcomings, it has been superseded by the build.sh
39 shell script as the recommended means for building NetBSD.
40
41 UPDATING Special notes for updating from an earlier revision of
42 NetBSD. It is important to read this file before every
43 build of an updated source tree.
44
45 build.sh Bourne-compatible shell script used for building the host
46 build tools and the NetBSD system from scratch. Can be
47 used for both native and cross builds, and should be used
48 instead of make(1) as it performs additional checks to
49 prevent common issues going undetected, such as building
50 with an outdated version of make(1).
51
52 crypto/dist/, dist/, gnu/dist/
53 Sources imported verbatim from third parties, without
54 mangling the existing build structure. Other source trees
55 in bin through usr.sbin use the NetBSD make(1) "reachover"
56 Makefile semantics when building these programs for a
57 native host.
58
59 distrib/, etc/
60 Sources for items used when making a full release
61 snapshot, such as files installed in DESTDIR/etc on the
62 destination system, boot media, and release notes.
63
64 doc/BUILDING.mdoc
65 The source to this document, in mdoc(7) format. Used to
66 generate BUILDING.
67
68 external/, sys/external/
69 Sources and build infrastructure for components imported
70 (mostly) unchanged from upstream maintainers, sorted by
71 applicable license. This is (slowly) replacing the
72 crypto/dist, dist, and gnu/dist directories.
73
74 external/mit/xorg/
75 "Reachover" build structure for modular Xorg; the source
76 is in X11SRCDIR.
77
78 mk.conf Optional source tree specific mk.conf(5), used (if
79 present) instead of /etc/mk.conf unless MAKECONF is
80 defined.
81
82 Note: Not part of the NetBSD source repository.
83
84 regress/, tests/
85 Regression test harness. Can be cross-compiled, but only
86 run natively. tests/ uses the atf(7) test framework;
87 regress/ contains older tests that have not yet been
88 migrated to atf(7).
89
90 sys/ NetBSD kernel sources.
91
92 tools/ "Reachover" build structure for the host build tools.
93 This has a special method of determining out-of-date
94 status.
95
96 tools/compat/README
97 Special notes for cross-hosting a NetBSD build on non-
98 NetBSD platforms.
99
100 Other directories including bin/ ... usr.sbin/
101 Sources to the NetBSD userland (non-kernel) programs. If
102 any of these directories are missing, they will be skipped
103 during the build.
104
105 Build tree layout
106 The NetBSD build tree is described in hier(7) (whose mdoc(7) source is in
107 share/man/man7/hier.7), and the release layout is described in release(7)
108 (whose mdoc(7) source is in share/man/man7/release.7).
109
110 CONFIGURATION
111 Environment variables
112 Several environment variables control the behaviour of NetBSD builds.
113
114 HOST_CC Path name to C compiler used to create the toolchain.
115
116 Default: "cc".
117
118 HOST_CFLAGS Flags passed to the host C compiler.
119
120 Default: "-O".
121
122 HOST_CPPFLAGS Flags passed to the host C/C++ pre-processor.
123
124 Default: Unset.
125
126 HOST_CXX Path name to C++ compiler used to create the toolchain.
127
128 Default: Unset, but defaults to "c++" where required.
129
130 HOST_CXXFLAGS Flags passed to the host C++ compiler.
131
132 Default: Unset.
133
134 HOST_SH Path name to a shell available on the host system and
135 suitable for use during the build. The NetBSD build
136 system requires a modern Bourne-like shell with POSIX-
137 compliant features, and also requires support for the
138 "local" keyword to declare local variables in shell
139 functions (which is a widely-implemented but non-
140 standardised feature).
141
142 Depending on the host system, a suitable shell may be
143 /bin/sh, /usr/xpg4/bin/sh, /bin/ksh (provided it is a
144 variant of ksh that supports the "local" keyword, such as
145 ksh88, but not ksh93), or /usr/local/bin/bash.
146
147 Most parts of the build require HOST_SH to be an absolute
148 path; however, build.sh allows it to be a simple command
149 name, which will be converted to an absolute path by
150 searching the PATH.
151
152 Default: "sh".
153
154 INSTALLBOOT_UBOOT_PATHS
155 A colon-separated list of search paths used by
156 installboot(8) to find U-Boot packages.
157
158 Default: Unset.
159
160 MACHINE Machine type, e.g., "macppc".
161
162 Default: Unset.
163
164 MACHINE_ARCH Machine architecture, e.g., "powerpc".
165
166 Default: Unset.
167
168 MAKE Path name to invoke make(1) as.
169
170 Default: "make".
171
172 MAKECONF The name of the make(1) configuration file. See make
173 variables and mk.conf(5).
174
175 Note: Only settable in the process environment.
176
177 Default: "/etc/mk.conf", although build.sh will set the
178 default to the full path to mk.conf if the latter is
179 present in the same directory as build.sh.
180
181 MAKEFLAGS Flags to invoke make(1) with.
182
183 Note: build.sh ignores the value of MAKEFLAGS passed in
184 the environment, but allows MAKEFLAGS to be set via the
185 -V option.
186
187 Default: "-X" on systems with a small ARG_MAX (Cygwin,
188 Darwin, FreeBSD); otherwise unset.
189
190 MAKEOBJDIR Directory to use as the .OBJDIR for the current
191 directory. The value is subjected to variable expansion
192 by make(1). Typical usage is to set this variable to a
193 value involving the use of `${.CURDIR:S...}' or
194 `${.CURDIR:C...}', to derive the value of .OBJDIR from
195 the value of .CURDIR. Used only if MAKEOBJDIRPREFIX is
196 not defined.
197
198 Note: MAKEOBJDIR can be provided only in the environment
199 or via the -O flag of build.sh; it cannot usefully be set
200 inside a Makefile, including in mk.conf(5) or MAKECONF.
201
202 Default: Unset.
203
204 MAKEOBJDIRPREFIX
205 Top level directory of the object directory tree. The
206 value is subjected to variable expansion by make(1).
207 build.sh will create the ${MAKEOBJDIRPREFIX} directory if
208 necessary, but if make(1) is used without build.sh, then
209 rules in <bsd.obj.mk> will abort the build if the
210 ${MAKEOBJDIRPREFIX} directory does not exist. If the
211 value is defined and valid, then
212 ${MAKEOBJDIRPREFIX}/${.CURDIR} is used as the .OBJDIR for
213 the current directory. The current directory may be read
214 only.
215
216 Note: MAKEOBJDIRPREFIX can be provided only in the
217 environment or via the -M flag of build.sh; it cannot
218 usefully be set inside a Makefile, including in
219 mk.conf(5) or MAKECONF.
220
221 Default: Unset.
222
223 TMPDIR Top-level directory to store temporary directories used
224 by build.sh before paths to other directories such as
225 .OBJDIR can be determined.
226
227 Note: Must support execution of binaries. I.e., without
228 mount(8)'s -o noexec option.
229
230 Default: "/tmp".
231
232 make variables
233 Variables that control the behavior of NetBSD builds are documented in
234 mk.conf(5) (whose mdoc(7) source is in share/man/man5/mk.conf.5).
235
236 Unless otherwise specified, these variables may be set in either the
237 process environment or the make(1) configuration file mk.conf(5)
238 specified by MAKECONF.
239
240 Note: Variables set in the environment, either directly or via build.sh
241 options to set specific values in the nbmake-MACHINE wrapper script do
242 not override variables set in the mk.conf(5) file. To allow variables in
243 mk.conf(5) to be overridden by the environment or build.sh options,
244 define the variables using the "?=" make(1) variable assignment operator.
245 For example,
246
247 MAKEVERBOSE?=1
248
249 The supported mk.conf(5) make variables are:
250
251 BSDOBJDIR, BSDSRCDIR, BUILD, BUILDID, BUILDINFO, BUILDSEED,
252 CDEXTRA, CONFIGOPTS, COPTS, CPUFLAGS, DESTDIR, EXTERNAL_TOOLCHAIN,
253 INSTALLBOOT_BOARDS, INSTALLWORLDDIR, KERNARCHDIR, KERNCONFDIR,
254 KERNEL_DIR, KERNOBJDIR, KERNSRCDIR, LOCALTIME, MAKEVERBOSE,
255 MKAMDGPUFIRMWARE, MKARGON2, MKARZERO, MKATF, MKBINUTILS, MKBSDDIFF,
256 MKBSDGREP, MKBSDTAR, MKCATPAGES, MKCLEANSRC, MKCLEANVERIFY,
257 MKCOMPAT, MKCOMPATMODULES, MKCOMPATTESTS, MKCOMPATX11, MKCOMPLEX,
258 MKCROSSGDB, MKCTF, MKCVS, MKCXX, MKDEBUG, MKDEBUGKERNEL,
259 MKDEBUGLIB, MKDEBUGTOOLS, MKDEPINCLUDES, MKDOC, MKDTB, MKDTC,
260 MKDTRACE, MKDYNAMICROOT, MKFIRMWARE, MKGCC, MKGCCCMDS, MKGDB,
261 MKGROFF, MKGROFFHTMLDOC, MKHESIOD, MKHOSTOBJ, MKHTML, MKIEEEFP,
262 MKINET6, MKINFO, MKIPFILTER, MKISCSI, MKKERBEROS, MKKMOD, MKKYUA,
263 MKLDAP, MKLIBCSANITIZER, MKLIBCXX, MKLIBSTDCXX, MKLINKLIB, MKLINT,
264 MKLLVM, MKLLVMRT, MKLVM, MKMAKEMANDB, MKMAN, MKMANDOC, MKMANZ,
265 MKMDNS, MKNLS, MKNOUVEAUFIRMWARE, MKNPF, MKNSD, MKOBJ, MKOBJDIRS,
266 MKPAM, MKPCC, MKPF, MKPIC, MKPICINSTALL, MKPICLIB, MKPIE,
267 MKPIGZGZIP, MKPOSTFIX, MKPROFILE, MKRADEONFIRMWARE, MKRELRO,
268 MKREPRO, MKREPRO_TIMESTAMP, MKRUMP, MKSANITIZER, MKSHARE, MKSKEY,
269 MKSLJIT, MKSOFTFLOAT, MKSTATICLIB, MKSTATICPIE, MKSTRIPIDENT,
270 MKSTRIPSYM, MKTEGRAFIRMWARE, MKTPM, MKUNBOUND, MKUNPRIVED,
271 MKUPDATE, MKX11, MKX11FONTS, MKX11MOTIF, MKXORG_SERVER, MKYP,
272 MKZFS, NETBSDSRCDIR, NETBSD_OFFICIAL_RELEASE, NOCLEANDIR,
273 NODISTRIBDIRS, NOINCLUDES, OBJMACHINE, RELEASEDIR,
274 RUMPUSER_THREADS, RUMP_CURLWP, RUMP_DEBUG, RUMP_DIAGNOSTIC,
275 RUMP_KTRACE, RUMP_LOCKDEBUG, RUMP_LOCKS_UP, RUMP_NBCOMPAT,
276 RUMP_VIRTIF, RUMP_VNODE_LOCKDEBUG, TOOLCHAIN_MISSING, TOOLDIR,
277 USETOOLS, USE_FORT, USE_HESIOD, USE_INET6, USE_JEMALLOC,
278 USE_KERBEROS, USE_LDAP, USE_LIBCSANITIZER, USE_PAM, USE_PIGZGZIP,
279 USE_SANITIZER, USE_SKEY, USE_SSP, USE_XZ_SETS, USE_YP,
280 X11MOTIFPATH, X11SRCDIR.
281
282 The obsolete mk.conf(5) make variables are:
283
284 EXTSRCSRCDIR, MKBFD, MKCRYPTO, MKEXTSRC, MKKDEBUG, MKKERBEROS4,
285 MKLLD, MKLLDB, MKMCLINKER, MKPERFUSE, MKTOOLSDEBUG, NBUILDJOBS,
286 SHAREDSTRINGS, USE_COMBINE, USE_NEW_TOOLCHAIN.
287
288 BUILDING
289 make command line options
290 This is not a summary of all the options available to make(1); only the
291 options used most frequently with NetBSD builds are listed here.
292
293 -j njob Run up to njob make(1) subjobs in parallel. Makefiles should
294 use .WAIT or have explicit dependencies as necessary to
295 enforce build ordering.
296
297 -m dir Specify the default directory for searching for system
298 Makefile segments, mainly the <bsd.*.mk> files. When building
299 any full NetBSD source tree, this should be set to the
300 "share/mk" directory in the source tree. This is set
301 automatically when building from the top level, or when using
302 build.sh.
303
304 -n Show the commands that would have been executed, but do not
305 actually execute them. This will still cause recursion to
306 take place.
307
308 -V var Show make(1)'s idea of the value of var. Does not build any
309 targets.
310
311 var=value Set the variable var to value, overriding any setting
312 specified by the process environment, the MAKECONF
313 configuration file, or the system Makefile segments.
314
315 make targets
316 These default targets may be built by running make(1) in any subtree of
317 the NetBSD source code. It is recommended that none of these be used
318 from the top level Makefile; as a specific exception, "make obj" and
319 "make cleandir" are useful in that context.
320
321 all Build programs, libraries, and preformatted documentation.
322
323 clean Remove program and library object code files.
324
325 cleandir Same as clean, but also remove preformatted documentation,
326 dependency files generated by "make depend", and any other
327 files known to be created at build time.
328
329 depend Create dependency files (.depend) containing more detailed
330 information about the dependencies of source code on header
331 files. Allows programs to be recompiled automatically when a
332 dependency changes.
333
334 dependall Does a "make depend" immediately followed by a "make all".
335 This improves cache locality of the build since both passes
336 read the source files in their entirety.
337
338 distclean Synonym for cleandir.
339
340 includes Build and install system header files. Typically needed
341 before any system libraries or programs can be built.
342
343 install Install programs, libraries, and documentation into DESTDIR.
344 Few files will be installed to DESTDIR/dev, DESTDIR/etc,
345 DESTDIR/root or DESTDIR/var in order to prevent user supplied
346 configuration data from being overwritten.
347
348 lint Run lint(1) against the C source code, where appropriate, and
349 generate system-installed lint libraries.
350
351 obj Create object directories to be used for built files, instead
352 of building directly in the source tree.
353
354 tags Create ctags(1) searchable function lists usable by the ex(1)
355 and vi(1) text editors.
356
357 make targets for the top level
358 Additional make(1) targets are usable specifically from the top source
359 level to facilitate building the entire NetBSD source tree.
360
361 build Build the entire NetBSD system (except the kernel). This
362 orders portions of the source tree such that prerequisites
363 will be built in the proper order.
364
365 distribution Do a "make build", and then install a full distribution
366 (which does not include a kernel) into DESTDIR, including
367 files in DESTDIR/dev, DESTDIR/etc, DESTDIR/root and
368 DESTDIR/var.
369
370 buildworld As per "make distribution", except that it ensures that
371 DESTDIR is not the root directory.
372
373 installworld Install the distribution from DESTDIR to INSTALLWORLDDIR,
374 which defaults to the root directory. Ensures that
375 INSTALLWORLDDIR is not the root directory if cross
376 compiling.
377
378 The INSTALLSETS environment variable may be set to a space-
379 separated list of distribution sets to be installed. By
380 default, all sets except "etc" and "xetc" are installed, so
381 most files in INSTALLWORLDDIR/etc will not be installed or
382 modified.
383
384 Note: Before performing this operation with
385 INSTALLWORLDDIR=/, it is highly recommended that you
386 upgrade your kernel and reboot. After performing this
387 operation, it is recommended that you use etcupdate(8) to
388 update files in INSTALLWORLDDIR/etc, and postinstall(8) to
389 check for or fix inconsistencies.
390
391 sets Create distribution sets from DESTDIR into
392 RELEASEDIR/RELEASEMACHINEDIR/binary/sets. Should be run
393 after "make distribution", as "make build" alone does not
394 install all of the required files.
395
396 sourcesets Create source sets of the source tree into
397 RELEASEDIR/source/sets.
398
399 syspkgs Create syspkgs from DESTDIR into
400 RELEASEDIR/RELEASEMACHINEDIR/binary/syspkgs. Should be run
401 after "make distribution", as "make build" alone does not
402 install all of the required files.
403
404 release Do a "make distribution", build kernels, distribution
405 media, and install sets (this as per "make sets"), and then
406 package the system into a standard release layout as
407 described by release(7). This requires that RELEASEDIR be
408 set (see above).
409
410 iso-image Create a NetBSD installation CD-ROM image in the
411 RELEASEDIR/images directory. The CD-ROM file system will
412 have a layout as described in release(7).
413
414 For most machine types, the CD-ROM will be bootable, and
415 will automatically run the sysinst(8) menu-based
416 installation program, which can be used to install or
417 upgrade a NetBSD system. Bootable CD-ROMs also contain
418 tools that may be useful in repairing a damaged NetBSD
419 installation.
420
421 Before "make iso-image" is attempted, RELEASEDIR must be
422 populated by "make release" or equivalent.
423
424 Note: Other, smaller, CD-ROM images may be created in the
425 RELEASEDIR/RELEASEMACHINEDIR/installation/cdrom directory
426 by "make release". These smaller images usually contain
427 the same tools as the larger images in RELEASEDIR/images,
428 but do not contain additional content such as the
429 distribution sets.
430
431 Note: The mac68k port still uses an older method of
432 creating CD-ROM images. This requires the mkisofs(1)
433 utility, which is not part of NetBSD, but which can be
434 installed from pkgsrc/sysutils/cdrtools.
435
436 iso-image-source
437 Create a NetBSD installation CD-ROM image in the
438 RELEASEDIR/images directory. The CD-ROM file system will
439 have a layout as described in release(7). It will have top
440 level directories for the machine type and source.
441
442 For most machine types, the CD-ROM will be bootable, and
443 will automatically run the sysinst(8) menu-based
444 installation program, which can be used to install or
445 upgrade a NetBSD system. Bootable CD-ROMs also contain
446 tools that may be useful in repairing a damaged NetBSD
447 installation.
448
449 Before "make iso-image-source" is attempted, RELEASEDIR
450 must be populated by "make sourcesets release" or
451 equivalent.
452
453 Note: Other, smaller, CD-ROM images may be created in the
454 RELEASEDIR/RELEASEMACHINEDIR/installation/cdrom directory
455 by "make release". These smaller images usually contain
456 the same tools as the larger images in RELEASEDIR/images,
457 but do not contain additional content such as the
458 distribution sets.
459
460 Note: The mac68k port still uses an older method of
461 creating CD-ROM images. This requires the mkisofs(1)
462 utility, which is not part of NetBSD, but which can be
463 installed from pkgsrc/sysutils/cdrtools.
464
465 install-image
466 Create a bootable NetBSD installation disk image in the
467 RELEASEDIR/images directory. The installation disk image
468 is suitable for copying to bootable USB flash memory
469 sticks, etc., for machines which are able to boot from such
470 devices. The file system in the bootable disk image will
471 have a layout as described in release(7).
472
473 The installation image is bootable, and will automatically
474 run the sysinst(8) menu-based installation program, which
475 can be used to install or upgrade a NetBSD system. The
476 image also contains tools that may be useful in repairing a
477 damaged NetBSD installation.
478
479 Before "make install-image" is attempted, RELEASEDIR must
480 be populated by "make release" or equivalent. The build
481 must have been performed with MKUNPRIVED=yes because "make
482 install-image" relies on information in DESTDIR/METALOG.
483
484 live-image Create NetBSD live images in the RELEASEDIR/images
485 directory. The live image contains all necessary files to
486 boot NetBSD up to multi-user mode, including all files
487 which should be extracted during installation, NetBSD
488 disklabel, bootloaders, etc.
489
490 The live image is suitable for use as a disk image in
491 virtual machine environments such as QEMU, and also useful
492 to boot NetBSD from a USB flash memory stick on a real
493 machine, without the need for installation.
494
495 Before "make live-image" is attempted, RELEASEDIR must be
496 populated by "make release" or equivalent. The build must
497 have been performed with MKUNPRIVED=yes because "make
498 install-image" relies on information in DESTDIR/METALOG.
499
500 regression-tests
501 Can only be run after building the regression tests in the
502 directory "regress". Runs those compiled regression tests
503 on the local host.
504
505 Note: Most tests are now managed instead using atf(7); this
506 target should probably run those as well but currently does
507 not.
508
509 The build.sh script
510 This script file is a shell script designed to build the entire NetBSD
511 system on any host with a suitable modern shell and some common
512 utilities. The required shell features are described under the HOST_SH
513 variable.
514
515 If a host system's default shell does support the required features, then
516 we suggest that you explicitly specify a suitable shell using a command
517 like
518
519 /path/to/suitable/shell build.sh [options]
520
521 The above command will usually enable build.sh to automatically set
522 HOST_SH=/path/to/suitable/shell, but if that fails, then the following
523 set of commands may be used instead:
524
525 HOST_SH=/path/to/suitable/shell
526 export HOST_SH
527 ${HOST_SH} build.sh [options]
528
529 If build.sh detects that it is being executed under an unsuitable shell,
530 it attempts to exec a suitable shell instead, or shows an error message.
531 If HOST_SH is not set explicitly, then build.sh sets a default using
532 heuristics dependent on the host platform, or from the shell under which
533 build.sh is executed (if that can be determined), or using the first copy
534 of sh found in PATH.
535
536 All cross-compile builds, and most native builds, of the entire system
537 should make use of build.sh rather than just running "make". This way,
538 the make(1) program will be bootstrapped properly, in case the host
539 system has an older or incompatible "make" program.
540
541 When compiling the entire system via build.sh, many make(1) variables are
542 set for you in order to help encapsulate the build process. In the list
543 of options below, variables that are automatically set by build.sh are
544 noted where applicable.
545
546 The following operations are supported by build.sh:
547
548 build Build the system as per "make build". Before the main part
549 of the build commences, this command runs the obj operation
550 (unless the -o option is given), "make cleandir" (unless
551 the -u option is given), and the tools operation.
552
553 distribution Build a full distribution as per "make distribution". This
554 command first runs the build operation.
555
556 release Build a full release as per "make release". This command
557 first runs the distribution operation.
558
559 help Show a help message, and exit.
560
561 makewrapper Create the nbmake-MACHINE wrapper script. This operation
562 is automatically performed for any of the other operations.
563
564 cleandir Perform "make cleandir".
565
566 obj Perform "make obj".
567
568 tools Build and install the host tools from src/tools. This
569 command will first run "make obj" and "make cleandir" in
570 the tools subdirectory unless the -o or -u options
571 (respectively) are given.
572
573 install=idir Install the contents of DESTDIR to idir, using "make
574 installworld".
575
576 Note: Files that are part of the "etc" or "xetc" sets will
577 not be installed, unless overridden by the INSTALLSETS
578 environment variable.
579
580 kernel=kconf Build a new kernel. The kconf argument is the name of a
581 configuration file suitable for use by config(1). If kconf
582 does not contain any `/' characters, the configuration file
583 is expected to be found in the KERNCONFDIR directory, which
584 is typically sys/arch/MACHINE/conf. The new kernel will be
585 built in a subdirectory of KERNOBJDIR, which is typically
586 sys/arch/MACHINE/compile or an associated object directory.
587
588 This command does not imply the tools command; run the
589 tools command first unless it is certain that the tools
590 already exist and are up to date.
591
592 This command will run "make cleandir" on the kernel in
593 question first unless the -u option is given.
594
595 kernel.gdb=kconf
596 Build a new kernel with debug information. Similar to the
597 above kernel=kconf operation, but creates a netbsd.gdb file
598 alongside of the kernel netbsd, which contains a full
599 symbol table and can be used for debugging (for example
600 with a cross-gdb built by MKCROSSGDB).
601
602 kernels This command will build all kernels defined in port
603 specific release build procedure.
604
605 This command internally calls the kernel=kconf operation
606 for each found kernel configuration file.
607
608 modules This command will build kernel modules and install them
609 into DESTDIR.
610
611 releasekernel=kconf
612 Install a gzip(1)ed copy of the kernel previously built by
613 kernel=kconf into
614 RELEASEDIR/RELEASEMACHINEDIR/binary/kernel, usually as
615 netbsd-kconf.gz, although the "netbsd" prefix is determined
616 from the "config" directives in kconf.
617
618 sets Perform "make sets".
619
620 sourcesets Perform "make sourcesets".
621
622 syspkgs Perform "make syspkgs".
623
624 iso-image Perform "make iso-image".
625
626 iso-image-source
627 Perform "make iso-image-source".
628
629 install-image
630 Perform "make install-image".
631
632 live-image Perform "make live-image".
633
634 list-arch Show a list of valid MACHINE and MACHINE_ARCH settings, the
635 default MACHINE_ARCH for each MACHINE, and aliases for
636 MACHINE/MACHINE_ARCH pairs, and then exits. The -m or -a
637 options (or both) may be used to specify glob patterns that
638 will be used to narrow the list of results; for example,
639 "build.sh -m 'evb*' -a '*arm*' list-arch" will list all
640 known MACHINE/MACHINE_ARCH values in which either MACHINE
641 or ALIAS matches the pattern `evb*', and MACHINE_ARCH
642 matches the pattern `*arm*'.
643
644 The following command line options alter the behaviour of the build.sh
645 operations described above:
646
647 -a arch Set the value of MACHINE_ARCH to arch. See the -m option for
648 more information.
649
650 -B buildid
651 Set the value of BUILDID to buildid. This will also append the
652 build identifier to the name of the nbmake-MACHINE wrapper
653 script so that the resulting name is of the form
654 "nbmake-MACHINE-BUILDID".
655
656 -C cdextras
657 Append cdextras to the CDEXTRA variable, which is a space-
658 separated list of files or directories that will be added to
659 the CD-ROM image that may be create by the "iso-image" or
660 "iso-image-source" operations. Files will be added to the root
661 of the CD-ROM image, whereas directories will be copied
662 recursively. If relative paths are specified, they will be
663 converted to absolute paths before being used. Multiple paths
664 may be specified via multiple -C options, or via a single
665 option whose argument contains multiple space-separated paths.
666
667 -c compiler
668 Select the compiler for the toolchain to build NetBSD and for
669 inclusion in the NetBSD distribution. Supported choices:
670
671 clang
672
673 gcc [default]
674
675 The compiler used to build the toolchain can be different; see
676 HOST_CC and HOST_CXX.
677
678 -D dest Set the value of DESTDIR to dest. If a relative path is
679 specified, it will be converted to an absolute path before
680 being used.
681
682 -E Set `expert' mode. This overrides various sanity checks, and
683 allows: DESTDIR does not have to be set to a non-root path for
684 builds, and MKUNPRIVED=yes does not have to be set when
685 building as a non-root user.
686
687 Note: It is highly recommended that you know what you are doing
688 when you use this option.
689
690 -h Show a help message, and exit.
691
692 -j njob Run up to njob make(1) subjobs in parallel; passed through to
693 make(1). If you see failures for reasons other than running
694 out of memory while using build.sh with -j, please save
695 complete build logs so the failures can be analyzed.
696
697 To achieve the fastest builds, -j values between (1 + the
698 number of CPUs) and (2 * the number of CPUs) are recommended.
699 Use lower values on machines with limited memory or I/O
700 bandwidth.
701
702 -M obj Set MAKEOBJDIRPREFIX to obj. Unsets MAKEOBJDIR. See "-O obj"
703 for more information.
704
705 For instance, if the source directory is /usr/src, a setting of
706 "-M /usr/obj" will place build-time files under
707 /usr/obj/usr/src/bin, /usr/obj/usr/src/lib,
708 /usr/obj/usr/src/usr.bin, and so forth.
709
710 If a relative path is specified, it will be converted to an
711 absolute path before being used. build.sh imposes the
712 restriction that the argument to the -M option must not begin
713 with a "$" (dollar sign) character; otherwise it would be too
714 difficult to determine whether the value is an absolute or a
715 relative path. If the directory does not already exist,
716 build.sh will create it.
717
718 -m mach Set the value of MACHINE to mach, unless the mach argument is
719 an alias that refers to a MACHINE/MACHINE_ARCH pair, in which
720 case both MACHINE and MACHINE_ARCH are set from the alias.
721 Such aliases are interpreted entirely by build.sh; they are not
722 used by any other part of the build system. The MACHINE_ARCH
723 setting implied by mach will override any value of MACHINE_ARCH
724 in the process environment, but will not override a value set
725 by the -a option. All cross builds require -m, but if unset on
726 a NetBSD host, the host's value of MACHINE will be detected and
727 used automatically.
728
729 See the list-arch operation for a way to get a list of valid
730 MACHINE and MACHINE_ARCH settings.
731
732 -N noiselevel
733 Set the "noisiness" level of the build, by setting MAKEVERBOSE
734 to noiselevel.
735
736 -n Show the commands that would be executed by build.sh, but do
737 not make any changes. This is similar in concept to "make -n".
738
739 -O obj Create an appropriate transform macro for MAKEOBJDIR that will
740 place the built object files under obj. Unsets
741 MAKEOBJDIRPREFIX.
742
743 For instance, a setting of "-O /usr/obj" will place build-time
744 files under /usr/obj/bin, /usr/obj/lib, /usr/obj/usr.bin, and
745 so forth.
746
747 If a relative path is specified, it will be converted to an
748 absolute path before being used. build.sh imposes the
749 restriction that the argument to the -O option must not contain
750 a "$" (dollar sign) character. If the directory does not
751 already exist, build.sh will create it.
752
753 In normal use, exactly one of the -M or -O options should be
754 specified. If neither -M nor -O is specified, then a default
755 object directory will be chosen according to rules in
756 <bsd.obj.mk>. Relying on this default is not recommended
757 because it is determined by complex rules that are influenced
758 by the values of several variables and by the location of the
759 source directory.
760
761 Note: Placing the obj directory location outside of the default
762 source tree hierarchy makes it easier to manually clear out old
763 files in the event the "make cleandir" operation is unable to
764 do so. (See CAVEATS below.)
765
766 Note: The use of one of -M or -O is the only means of building
767 multiple machine architecture userlands from the same source
768 tree without cleaning between builds (in which case, one would
769 specify distinct obj locations for each).
770
771 -o Set the value of MKOBJDIRS to "no". Otherwise, it will be
772 automatically set to "yes". This default is opposite to the
773 behaviour when not using build.sh.
774
775 -P Set the value of MKREPRO and MKREPRO_TIMESTAMP to the latest
776 source CVS timestamp for reproducible builds.
777
778 -R rel Set the value of RELEASEDIR to rel. If a relative path is
779 specified, it will be converted to an absolute path before
780 being used.
781
782 -r Remove the contents of DESTDIR and TOOLDIR before building
783 (provides a clean starting point). This will skip deleting
784 DESTDIR if building on a native system to the root directory.
785
786 -S seed Change the value of BUILDSEED to seed. This should rarely be
787 necessary.
788
789 -T tools Set the value of TOOLDIR to tools. If a relative path is
790 specified, it will be converted to an absolute path before
791 being used. If set, the bootstrap "make" will only be rebuilt
792 if the source files for make(1) have changed.
793
794 -U Set MKUNPRIVED=yes.
795
796 -u Set MKUPDATE=yes.
797
798 -V var=[value]
799 Set the environment variable var to an optional value. This is
800 propagated to the nbmake-MACHINE wrapper script.
801
802 -w wrapper
803 Create the nbmake-MACHINE wrapper script (see below) in a
804 custom location, specified by wrapper. This allows, for
805 instance, to place the wrapper script in PATH automatically.
806
807 Note: wrapper is the full name of the file, not just a
808 directory name. If a relative path is specified, it will be
809 converted to an absolute path before being used.
810
811 -X x11src
812 Set the value of X11SRCDIR to x11src. If a relative path is
813 specified, it will be converted to an absolute path before
814 being used.
815
816 -x Set MKX11=yes.
817
818 -Z var Unset ("zap") the environment variable var. This is propagated
819 to the nbmake-MACHINE wrapper script.
820
821 -? Show a help message, and exit.
822
823 The nbmake-MACHINE wrapper script
824 If using the build.sh script to build NetBSD, a nbmake-MACHINE wrapper
825 script will be created in TOOLDIR/bin upon the first build to assist in
826 building subtrees on a cross-compile host.
827
828 The nbmake-MACHINE wrapper script can be invoked in lieu of make(1), and
829 will instead call the up-to-date version of "nbmake" installed into
830 TOOLDIR/bin with several key variables pre-set, including MACHINE,
831 MACHINE_ARCH, and TOOLDIR. nbmake-MACHINE will also set variables
832 specified with -V, and unset variables specified with -Z. Note that by
833 default these variables will not override mk.conf(5); see make variables
834 for more details.
835
836 This wrapper script can be symlinked into a directory listed in PATH, or
837 called with an absolute path.
838
839 EXAMPLES
840 1. % ./build.sh [OPTIONS] tools kernel=GENERIC
841
842 Build a new toolchain, and use the new toolchain to configure and
843 build a new GENERIC kernel.
844
845 2. % ./build.sh [OPTIONS] -U distribution
846
847 Using unprivileged mode, build a complete distribution to a DESTDIR
848 directory that build.sh selects (and will show).
849
850 3. # ./build.sh [OPTIONS] -U install=/
851
852 As root, install to / the distribution that was built by example 2.
853 Even though this is run as root, -U is required so that the
854 permissions stored in DESTDIR/METALOG are correctly applied to the
855 files as they're copied to /.
856
857 4. % ./build.sh [OPTIONS] -U -u release
858
859 Using unprivileged mode, build a complete release to DESTDIR and
860 RELEASEDIR directories that build.sh selects (and will show).
861 MKUPDATE=yes (-u) is set to prevent the "make cleandir", so that if
862 this is run after example 2, it doesn't need to redo that portion of
863 the release build.
864
865 SEE ALSO
866 config(1), ctags(1), ex(1), gzip(1), lint(1), make(1), mandoc(1),
867 mkisofs(1), nroff(1), vi(1), mk.conf(5), atf(7), hier(7), mdoc(7),
868 release(7), etcupdate(8), installboot(8), mount(8), postinstall(8),
869 sysinst(8), pkgsrc/sysutils/cdrtools
870
871 Note: The NetBSD manual pages are also available at
872 https://man.netbsd.org
873
874 HISTORY
875 The build.sh based build scheme was introduced for NetBSD 1.6 as
876 USE_NEW_TOOLCHAIN, and re-worked to TOOLCHAIN_MISSING after that.
877
878 CAVEATS
879 After significant updates to third-party components in the source tree,
880 the "make cleandir" operation may be insufficient to clean out old files
881 in object directories. Instead, one may have to manually remove the
882 files. Consult the UPDATING file for notices concerning this.
883
884 NetBSD November 28, 2025 NetBSD
885