BUILDING revision 1.157 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38 its shortcomings, it has been superseded by the build.sh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50 with an outdated version of make(1).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 BUILDING
241 "make" command line options
242 This is not a summary of all the options available to make(1); only the
243 options used most frequently with NetBSD builds are listed here.
244
245 -j njob Run up to njob make(1) subjobs in parallel. Makefiles should
246 use .WAIT or have explicit dependencies as necessary to
247 enforce build ordering.
248
249 -m dir Specify the default directory for searching for system
250 Makefile segments, mainly the <bsd.*.mk> files. When building
251 any full NetBSD source tree, this should be set to the
252 "share/mk" directory in the source tree. This is set
253 automatically when building from the top level, or when using
254 build.sh.
255
256 -n Show the commands that would have been executed, but do not
257 actually execute them. This will still cause recursion to
258 take place.
259
260 -V var Show make(1)'s idea of the value of var. Does not build any
261 targets.
262
263 var=value Set the variable var to value, overriding any setting
264 specified by the process environment, the MAKECONF
265 configuration file, or the system Makefile segments.
266
267 "make" targets
268 These default targets may be built by running make(1) in any subtree of
269 the NetBSD source code. It is recommended that none of these be used
270 from the top level Makefile; as a specific exception, "make obj" and
271 "make cleandir" are useful in that context.
272
273 all Build programs, libraries, and preformatted documentation.
274
275 clean Remove program and library object code files.
276
277 cleandir Same as clean, but also remove preformatted documentation,
278 dependency files generated by "make depend", and any other
279 files known to be created at build time.
280
281 depend Create dependency files (.depend) containing more detailed
282 information about the dependencies of source code on header
283 files. Allows programs to be recompiled automatically when a
284 dependency changes.
285
286 dependall Does a "make depend" immediately followed by a "make all".
287 This improves cache locality of the build since both passes
288 read the source files in their entirety.
289
290 distclean Synonym for cleandir.
291
292 includes Build and install system header files. Typically needed
293 before any system libraries or programs can be built.
294
295 install Install programs, libraries, and documentation into DESTDIR.
296 Few files will be installed to DESTDIR/dev, DESTDIR/etc,
297 DESTDIR/root or DESTDIR/var in order to prevent user supplied
298 configuration data from being overwritten.
299
300 lint Run lint(1) against the C source code, where appropriate, and
301 generate system-installed lint libraries.
302
303 obj Create object directories to be used for built files, instead
304 of building directly in the source tree.
305
306 tags Create ctags(1) searchable function lists usable by the ex(1)
307 and vi(1) text editors.
308
309 "make" targets for the top level
310 Additional make(1) targets are usable specifically from the top source
311 level to facilitate building the entire NetBSD source tree.
312
313 build Build the entire NetBSD system (except the kernel). This
314 orders portions of the source tree such that prerequisites
315 will be built in the proper order.
316
317 distribution Do a "make build", and then install a full distribution
318 (which does not include a kernel) into DESTDIR, including
319 files in DESTDIR/dev, DESTDIR/etc, DESTDIR/root and
320 DESTDIR/var.
321
322 buildworld As per "make distribution", except that it ensures that
323 DESTDIR is not the root directory.
324
325 installworld Install the distribution from DESTDIR to INSTALLWORLDDIR,
326 which defaults to the root directory. Ensures that
327 INSTALLWORLDDIR is not the root directory if cross
328 compiling.
329
330 The INSTALLSETS environment variable may be set to a space-
331 separated list of distribution sets to be installed. By
332 default, all sets except "etc" and "xetc" are installed, so
333 most files in INSTALLWORLDDIR/etc will not be installed or
334 modified.
335
336 Note: Before performing this operation with
337 INSTALLWORLDDIR=/, it is highly recommended that you
338 upgrade your kernel and reboot. After performing this
339 operation, it is recommended that you use etcupdate(8) to
340 update files in INSTALLWORLDDIR/etc, and postinstall(8) to
341 check for or fix inconsistencies.
342
343 sets Create distribution sets from DESTDIR into
344 RELEASEDIR/RELEASEMACHINEDIR/binary/sets. Should be run
345 after "make distribution", as "make build" alone does not
346 install all of the required files.
347
348 sourcesets Create source sets of the source tree into
349 RELEASEDIR/source/sets.
350
351 syspkgs Create syspkgs from DESTDIR into
352 RELEASEDIR/RELEASEMACHINEDIR/binary/syspkgs. Should be run
353 after "make distribution", as "make build" alone does not
354 install all of the required files.
355
356 release Do a "make distribution", build kernels, distribution
357 media, and install sets (this as per "make sets"), and then
358 package the system into a standard release layout as
359 described by release(7). This requires that RELEASEDIR be
360 set (see above).
361
362 iso-image Create a NetBSD installation CD-ROM image in the
363 RELEASEDIR/images directory. The CD-ROM file system will
364 have a layout as described in release(7).
365
366 For most machine types, the CD-ROM will be bootable, and
367 will automatically run the sysinst(8) menu-based
368 installation program, which can be used to install or
369 upgrade a NetBSD system. Bootable CD-ROMs also contain
370 tools that may be useful in repairing a damaged NetBSD
371 installation.
372
373 Before "make iso-image" is attempted, RELEASEDIR must be
374 populated by "make release" or equivalent.
375
376 Note: Other, smaller, CD-ROM images may be created in the
377 RELEASEDIR/RELEASEMACHINEDIR/installation/cdrom directory
378 by "make release". These smaller images usually contain
379 the same tools as the larger images in RELEASEDIR/images,
380 but do not contain additional content such as the
381 distribution sets.
382
383 Note: The mac68k port still uses an older method of
384 creating CD-ROM images. This requires the mkisofs(1)
385 utility, which is not part of NetBSD, but which can be
386 installed from pkgsrc/sysutils/cdrtools.
387
388 iso-image-source
389 Create a NetBSD installation CD-ROM image in the
390 RELEASEDIR/images directory. The CD-ROM file system will
391 have a layout as described in release(7). It will have top
392 level directories for the machine type and source.
393
394 For most machine types, the CD-ROM will be bootable, and
395 will automatically run the sysinst(8) menu-based
396 installation program, which can be used to install or
397 upgrade a NetBSD system. Bootable CD-ROMs also contain
398 tools that may be useful in repairing a damaged NetBSD
399 installation.
400
401 Before "make iso-image-source" is attempted, RELEASEDIR
402 must be populated by "make sourcesets release" or
403 equivalent.
404
405 Note: Other, smaller, CD-ROM images may be created in the
406 RELEASEDIR/RELEASEMACHINEDIR/installation/cdrom directory
407 by "make release". These smaller images usually contain
408 the same tools as the larger images in RELEASEDIR/images,
409 but do not contain additional content such as the
410 distribution sets.
411
412 Note: The mac68k port still uses an older method of
413 creating CD-ROM images. This requires the mkisofs(1)
414 utility, which is not part of NetBSD, but which can be
415 installed from pkgsrc/sysutils/cdrtools.
416
417 install-image
418 Create a bootable NetBSD installation disk image in the
419 RELEASEDIR/images directory. The installation disk image
420 is suitable for copying to bootable USB flash memory
421 sticks, etc., for machines which are able to boot from such
422 devices. The file system in the bootable disk image will
423 have a layout as described in release(7).
424
425 The installation image is bootable, and will automatically
426 run the sysinst(8) menu-based installation program, which
427 can be used to install or upgrade a NetBSD system. The
428 image also contains tools that may be useful in repairing a
429 damaged NetBSD installation.
430
431 Before "make install-image" is attempted, RELEASEDIR must
432 be populated by "make release" or equivalent. The build
433 must have been performed with MKUNPRIVED=yes because "make
434 install-image" relies on information in DESTDIR/METALOG.
435
436 live-image Create NetBSD live images in the RELEASEDIR/images
437 directory. The live image contains all necessary files to
438 boot NetBSD up to multi-user mode, including all files
439 which should be extracted during installation, NetBSD
440 disklabel, bootloaders, etc.
441
442 The live image is suitable for use as a disk image in
443 virtual machine environments such as QEMU, and also useful
444 to boot NetBSD from a USB flash memory stick on a real
445 machine, without the need for installation.
446
447 Before "make live-image" is attempted, RELEASEDIR must be
448 populated by "make release" or equivalent. The build must
449 have been performed with MKUNPRIVED=yes because "make
450 install-image" relies on information in DESTDIR/METALOG.
451
452 regression-tests
453 Can only be run after building the regression tests in the
454 directory "regress". Runs those compiled regression tests
455 on the local host.
456
457 Note: Most tests are now managed instead using atf(7); this
458 target should probably run those as well but currently does
459 not.
460
461 The "build.sh" script
462 This script file is a shell script designed to build the entire NetBSD
463 system on any host with a suitable modern shell and some common
464 utilities. The required shell features are described under the HOST_SH
465 variable.
466
467 If a host system's default shell does support the required features, then
468 we suggest that you explicitly specify a suitable shell using a command
469 like
470
471 /path/to/suitable/shell build.sh [options]
472
473 The above command will usually enable build.sh to automatically set
474 HOST_SH=/path/to/suitable/shell, but if that fails, then the following
475 set of commands may be used instead:
476
477 HOST_SH=/path/to/suitable/shell
478 export HOST_SH
479 ${HOST_SH} build.sh [options]
480
481 If build.sh detects that it is being executed under an unsuitable shell,
482 it attempts to exec a suitable shell instead, or shows an error message.
483 If HOST_SH is not set explicitly, then build.sh sets a default using
484 heuristics dependent on the host platform, or from the shell under which
485 build.sh is executed (if that can be determined), or using the first copy
486 of sh found in PATH.
487
488 All cross-compile builds, and most native builds, of the entire system
489 should make use of build.sh rather than just running "make". This way,
490 the make(1) program will be bootstrapped properly, in case the host
491 system has an older or incompatible "make" program.
492
493 When compiling the entire system via build.sh, many make(1) variables are
494 set for you in order to help encapsulate the build process. In the list
495 of options below, variables that are automatically set by build.sh are
496 noted where applicable.
497
498 The following operations are supported by build.sh:
499
500 build Build the system as per "make build". Before the main part
501 of the build commences, this command runs the obj operation
502 (unless the -o option is given), "make cleandir" (unless
503 the -u option is given), and the tools operation.
504
505 distribution Build a full distribution as per "make distribution". This
506 command first runs the build operation.
507
508 release Build a full release as per "make release". This command
509 first runs the distribution operation.
510
511 help Show a help message, and exit.
512
513 makewrapper Create the nbmake-MACHINE wrapper. This operation is
514 automatically performed for any of the other operations.
515
516 cleandir Perform "make cleandir".
517
518 obj Perform "make obj".
519
520 tools Build and install the host tools from src/tools. This
521 command will first run "make obj" and "make cleandir" in
522 the tools subdirectory unless the -o or -u options
523 (respectively) are given.
524
525 install=idir Install the contents of DESTDIR to idir, using "make
526 installworld".
527
528 Note: Files that are part of the "etc" or "xetc" sets will
529 not be installed, unless overridden by the INSTALLSETS
530 environment variable.
531
532 kernel=kconf Build a new kernel. The kconf argument is the name of a
533 configuration file suitable for use by config(1). If kconf
534 does not contain any `/' characters, the configuration file
535 is expected to be found in the KERNCONFDIR directory, which
536 is typically sys/arch/MACHINE/conf. The new kernel will be
537 built in a subdirectory of KERNOBJDIR, which is typically
538 sys/arch/MACHINE/compile or an associated object directory.
539
540 This command does not imply the tools command; run the
541 tools command first unless it is certain that the tools
542 already exist and are up to date.
543
544 This command will run "make cleandir" on the kernel in
545 question first unless the -u option is given.
546
547 kernel.gdb=kconf
548 Build a new kernel with debug information. Similar to the
549 above kernel=kconf operation, but creates a netbsd.gdb file
550 alongside of the kernel netbsd, which contains a full
551 symbol table and can be used for debugging (for example
552 with a cross-gdb built by MKCROSSGDB).
553
554 kernels This command will build all kernels defined in port
555 specific release build procedure.
556
557 This command internally calls the kernel=kconf operation
558 for each found kernel configuration file.
559
560 modules This command will build kernel modules and install them
561 into DESTDIR.
562
563 releasekernel=kconf
564 Install a gzip(1)ed copy of the kernel previously built by
565 kernel=kconf into
566 RELEASEDIR/RELEASEMACHINEDIR/binary/kernel, usually as
567 netbsd-kconf.gz, although the "netbsd" prefix is determined
568 from the "config" directives in kconf.
569
570 sets Perform "make sets".
571
572 sourcesets Perform "make sourcesets".
573
574 syspkgs Perform "make syspkgs".
575
576 iso-image Perform "make iso-image".
577
578 iso-image-source
579 Perform "make iso-image-source".
580
581 install-image
582 Perform "make install-image".
583
584 live-image Perform "make live-image".
585
586 list-arch Show a list of valid MACHINE and MACHINE_ARCH settings, the
587 default MACHINE_ARCH for each MACHINE, and aliases for
588 MACHINE/MACHINE_ARCH pairs, and then exits. The -m or -a
589 options (or both) may be used to specify glob patterns that
590 will be used to narrow the list of results; for example,
591 "build.sh -m 'evb*' -a '*arm*' list-arch" will list all
592 known MACHINE/MACHINE_ARCH values in which either MACHINE
593 or ALIAS matches the pattern `evb*', and MACHINE_ARCH
594 matches the pattern `*arm*'.
595
596 The following command line options alter the behaviour of the build.sh
597 operations described above:
598
599 -a arch Set the value of MACHINE_ARCH to arch. See the -m option for
600 more information.
601
602 -B buildid
603 Set the value of BUILDID to buildid. This will also append the
604 build identifier to the name of the "make" wrapper script so
605 that the resulting name is of the form
606 "nbmake-MACHINE-BUILDID".
607
608 -C cdextras
609 Append cdextras to the CDEXTRA variable, which is a space-
610 separated list of files or directories that will be added to
611 the CD-ROM image that may be create by the "iso-image" or
612 "iso-image-source" operations. Files will be added to the root
613 of the CD-ROM image, whereas directories will be copied
614 recursively. If relative paths are specified, they will be
615 converted to absolute paths before being used. Multiple paths
616 may be specified via multiple -C options, or via a single
617 option whose argument contains multiple space-separated paths.
618
619 -c compiler
620 Select the compiler for the toolchain to build NetBSD and for
621 inclusion in the NetBSD distribution. Supported choices:
622
623 clang
624
625 gcc [default]
626
627 The compiler used to build the toolchain can be different; see
628 HOST_CC and HOST_CXX.
629
630 -D dest Set the value of DESTDIR to dest. If a relative path is
631 specified, it will be converted to an absolute path before
632 being used.
633
634 -E Set `expert' mode. This overrides various sanity checks, and
635 allows: DESTDIR does not have to be set to a non-root path for
636 builds, and MKUNPRIVED=yes does not have to be set when
637 building as a non-root user.
638
639 Note: It is highly recommended that you know what you are doing
640 when you use this option.
641
642 -h Show a help message, and exit.
643
644 -j njob Run up to njob make(1) subjobs in parallel; passed through to
645 make(1). If you see failures for reasons other than running
646 out of memory while using build.sh with -j, please save
647 complete build logs so the failures can be analyzed.
648
649 To achieve the fastest builds, -j values between (1 + the
650 number of CPUs) and (2 * the number of CPUs) are recommended.
651 Use lower values on machines with limited memory or I/O
652 bandwidth.
653
654 -M obj Set MAKEOBJDIRPREFIX to obj. Unsets MAKEOBJDIR. See "-O obj"
655 for more information.
656
657 For instance, if the source directory is /usr/src, a setting of
658 "-M /usr/obj" will place build-time files under
659 /usr/obj/usr/src/bin, /usr/obj/usr/src/lib,
660 /usr/obj/usr/src/usr.bin, and so forth.
661
662 If a relative path is specified, it will be converted to an
663 absolute path before being used. build.sh imposes the
664 restriction that the argument to the -M option must not begin
665 with a "$" (dollar sign) character; otherwise it would be too
666 difficult to determine whether the value is an absolute or a
667 relative path. If the directory does not already exist,
668 build.sh will create it.
669
670 -m mach Set the value of MACHINE to mach, unless the mach argument is
671 an alias that refers to a MACHINE/MACHINE_ARCH pair, in which
672 case both MACHINE and MACHINE_ARCH are set from the alias.
673 Such aliases are interpreted entirely by build.sh; they are not
674 used by any other part of the build system. The MACHINE_ARCH
675 setting implied by mach will override any value of MACHINE_ARCH
676 in the process environment, but will not override a value set
677 by the -a option. All cross builds require -m, but if unset on
678 a NetBSD host, the host's value of MACHINE will be detected and
679 used automatically.
680
681 See the list-arch operation for a way to get a list of valid
682 MACHINE and MACHINE_ARCH settings.
683
684 -N noiselevel
685 Set the "noisyness" level of the build, by setting MAKEVERBOSE
686 to noiselevel.
687
688 -n Show the commands that would be executed by build.sh, but do
689 not make any changes. This is similar in concept to "make -n".
690
691 -O obj Create an appropriate transform macro for MAKEOBJDIR that will
692 place the built object files under obj. Unsets
693 MAKEOBJDIRPREFIX.
694
695 For instance, a setting of "-O /usr/obj" will place build-time
696 files under /usr/obj/bin, /usr/obj/lib, /usr/obj/usr.bin, and
697 so forth.
698
699 If a relative path is specified, it will be converted to an
700 absolute path before being used. build.sh imposes the
701 restriction that the argument to the -O option must not contain
702 a "$" (dollar sign) character. If the directory does not
703 already exist, build.sh will create it.
704
705 In normal use, exactly one of the -M or -O options should be
706 specified. If neither -M nor -O is specified, then a default
707 object directory will be chosen according to rules in
708 <bsd.obj.mk>. Relying on this default is not recommended
709 because it is determined by complex rules that are influenced
710 by the values of several variables and by the location of the
711 source directory.
712
713 Note: Placing the obj directory location outside of the default
714 source tree hierarchy makes it easier to manually clear out old
715 files in the event the "make cleandir" operation is unable to
716 do so. (See CAVEATS below.)
717
718 Note: The use of one of -M or -O is the only means of building
719 multiple machine architecture userlands from the same source
720 tree without cleaning between builds (in which case, one would
721 specify distinct obj locations for each).
722
723 -o Set the value of MKOBJDIRS to "no". Otherwise, it will be
724 automatically set to "yes". This default is opposite to the
725 behaviour when not using build.sh.
726
727 -P Set the value of MKREPRO and MKREPRO_TIMESTAMP to the latest
728 source CVS timestamp for reproducible builds.
729
730 -R rel Set the value of RELEASEDIR to rel. If a relative path is
731 specified, it will be converted to an absolute path before
732 being used.
733
734 -r Remove the contents of DESTDIR and TOOLDIR before building
735 (provides a clean starting point). This will skip deleting
736 DESTDIR if building on a native system to the root directory.
737
738 -S seed Change the value of BUILDSEED to seed. This should rarely be
739 necessary.
740
741 -T tools Set the value of TOOLDIR to tools. If a relative path is
742 specified, it will be converted to an absolute path before
743 being used. If set, the bootstrap "make" will only be rebuilt
744 if the source files for make(1) have changed.
745
746 -U Set MKUNPRIVED=yes.
747
748 -u Set MKUPDATE=yes.
749
750 -V var=[value]
751 Set the environment variable var to an optional value. This is
752 propagated to the nbmake wrapper.
753
754 -w wrapper
755 Create the nbmake wrapper script (see below) in a custom
756 location, specified by wrapper. This allows, for instance, to
757 place the wrapper in PATH automatically.
758
759 Note: wrapper is the full name of the file, not just a
760 directory name. If a relative path is specified, it will be
761 converted to an absolute path before being used.
762
763 -X x11src
764 Set the value of X11SRCDIR to x11src. If a relative path is
765 specified, it will be converted to an absolute path before
766 being used.
767
768 -x Set MKX11=yes.
769
770 -Z var Unset ("zap") the environment variable var. This is propagated
771 to the nbmake wrapper.
772
773 -? Show a help message, and exit.
774
775 The "nbmake-MACHINE" wrapper script
776 If using the build.sh script to build NetBSD, a nbmake-MACHINE script
777 will be created in TOOLDIR/bin upon the first build to assist in building
778 subtrees on a cross-compile host.
779
780 nbmake-MACHINE can be invoked in lieu of make(1), and will instead call
781 the up-to-date version of "nbmake" installed into TOOLDIR/bin with
782 several key variables pre-set, including MACHINE, MACHINE_ARCH, and
783 TOOLDIR. nbmake-MACHINE will also set variables specified with -V, and
784 unset variables specified with -Z.
785
786 This script can be symlinked into a directory listed in PATH, or called
787 with an absolute path.
788
789 EXAMPLES
790 1. % ./build.sh [OPTIONS] tools kernel=GENERIC
791
792 Build a new toolchain, and use the new toolchain to configure and
793 build a new GENERIC kernel.
794
795 2. % ./build.sh [OPTIONS] -U distribution
796
797 Using unprivileged mode, build a complete distribution to a DESTDIR
798 directory that build.sh selects (and will show).
799
800 3. # ./build.sh [OPTIONS] -U install=/
801
802 As root, install to / the distribution that was built by example 2.
803 Even though this is run as root, -U is required so that the
804 permissions stored in DESTDIR/METALOG are correctly applied to the
805 files as they're copied to /.
806
807 4. % ./build.sh [OPTIONS] -U -u release
808
809 Using unprivileged mode, build a complete release to DESTDIR and
810 RELEASEDIR directories that build.sh selects (and will show).
811 MKUPDATE=yes (-u) is set to prevent the "make cleandir", so that if
812 this is run after example 2, it doesn't need to redo that portion of
813 the release build.
814
815 SEE ALSO
816 config(1), ctags(1), ex(1), gzip(1), lint(1), make(1), mandoc(1),
817 mkisofs(1), nroff(1), vi(1), mk.conf(5), atf(7), hier(7), mdoc(7),
818 release(7), etcupdate(8), installboot(8), mount(8), postinstall(8),
819 sysinst(8), pkgsrc/sysutils/cdrtools
820
821 Note: The NetBSD manual pages are also available at
822 https://man.netbsd.org
823
824 HISTORY
825 The build.sh based build scheme was introduced for NetBSD 1.6 as
826 USE_NEW_TOOLCHAIN, and re-worked to TOOLCHAIN_MISSING after that.
827
828 CAVEATS
829 After significant updates to third-party components in the source tree,
830 the "make cleandir" operation may be insufficient to clean out old files
831 in object directories. Instead, one may have to manually remove the
832 files. Consult the UPDATING file for notices concerning this.
833
834 NetBSD July 18, 2023 NetBSD
835