BUILDING revision 1.152
1BUILDING(8)                 System Manager's Manual                BUILDING(8)
2
3NAME
4     BUILDING - Procedure for building NetBSD from source code
5
6REQUIREMENTS
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 a special subtree, "tools", which uses the host
13     system to create a build toolchain for the target architecture.  The host
14     system must have at least C and C++ compilers in order to create the
15     toolchain (make is not required); all other tools are created as part of
16     the NetBSD build process.  (See the Environment variables section below
17     if you need to override or manually select your compilers.)
18
19FILES
20   Source tree layout
21     BUILDING       This document (in plaintext).  Generated from
22                    doc/BUILDING.mdoc.
23
24     Makefile       The main Makefile for NetBSD; should only be run for
25                    native builds with an appropriately up-to-date version of
26                    NetBSD make(1).  Intended for expert use with knowledge of
27                    its shortcomings, it has been superseded by the build.sh
28                    shell script as the recommended means for building NetBSD.
29
30     UPDATING       Special notes for updating from an earlier revision of
31                    NetBSD.  It is important to read this file before every
32                    build of an updated source tree.
33
34     build.sh       Bourne-compatible shell script used for building the host
35                    build tools and the NetBSD system from scratch.  Can be
36                    used for both native and cross builds, and should be used
37                    instead of make(1) as it performs additional checks to
38                    prevent common issues going undetected, such as building
39                    with an outdated version of make(1).
40
41     crypto/dist/, dist/, gnu/dist/
42                    Sources imported verbatim from third parties, without
43                    mangling the existing build structure.  Other source trees
44                    in bin through usr.sbin use the NetBSD make(1) "reachover"
45                    Makefile semantics when building these programs for a
46                    native host.
47
48     distrib/, etc/
49                    Sources for items used when making a full release
50                    snapshot, such as files installed in DESTDIR/etc on the
51                    destination system, boot media, and release notes.
52
53     doc/BUILDING.mdoc
54                    This document, in -mdoc troff format; the original copy.
55                    Used to generate BUILDING.
56
57     external, sys/external
58                    Sources and build infrastructure for components imported
59                    (mostly) unchanged from upstream maintainers, sorted by
60                    applicable license.  This is (slowly) replacing the
61                    crypto/dist, dist, and gnu/dist directories.
62
63     external/mit/xorg/
64                    "Reachover" build structure for modular Xorg; the source
65                    is in X11SRCDIR.
66
67     regress/, tests/
68                    Regression test harness.  Can be cross-compiled, but only
69                    run natively.  tests/ uses the atf(7) test framework;
70                    regress/ contains older tests that have not yet been
71                    migrated to atf(7).
72
73     sys/           NetBSD kernel sources.
74
75     tools/         "Reachover" build structure for the host build tools.
76                    This has a special method of determining out-of-date
77                    status.
78
79     tools/compat/README
80                    Special notes for cross-hosting a NetBSD build on non-
81                    NetBSD platforms.
82
83     Other directories including bin/ ... usr.sbin/
84                    Sources to the NetBSD userland (non-kernel) programs.  If
85                    any of these directories are missing, they will be skipped
86                    during the build.
87
88   Build tree layout
89     The NetBSD build tree is described in hier(7), and the release layout is
90     described in release(7).
91
92CONFIGURATION
93   Environment variables
94     Several environment variables control the behaviour of NetBSD builds.
95
96     HOST_CC         Path name to C compiler used to create the toolchain.
97
98     HOST_CFLAGS     Flags passed to the host C compiler.
99
100     HOST_CXX        Path name to C++ compiler used to create the toolchain.
101
102     HOST_CXXFLAGS   Flags passed to the host C++ compiler.
103
104     HOST_SH         Path name to a shell available on the host system and
105                     suitable for use during the build.  The NetBSD build
106                     system requires a modern Bourne-like shell with POSIX-
107                     compliant features, and also requires support for the
108                     "local" keyword to declare local variables in shell
109                     functions (which is a widely-implemented but non-
110                     standardised feature).
111
112                     Depending on the host system, a suitable shell may be
113                     /bin/sh, /usr/xpg4/bin/sh, /bin/ksh (provided it is a
114                     variant of ksh that supports the "local" keyword, such as
115                     ksh88, but not ksh93), or /usr/local/bin/bash.
116
117                     Most parts of the build require HOST_SH to be an absolute
118                     path; however, build.sh allows it to be a simple command
119                     name, which will be converted to an absolute path by
120                     searching the PATH.
121
122     INSTALLBOOT_UBOOT_PATHS
123                     A colon-separated list of search paths used by
124                     installboot(8) to find U-Boot packages.
125
126     MACHINE         Machine type, e.g., "macppc".
127
128     MACHINE_ARCH    Machine architecture, e.g., "powerpc".
129
130     MAKE            Path name to invoke make(1) as.
131
132     MAKECONF        The name of the make(1) configuration file.  See "make"
133                     variables and mk.conf(5).
134
135                     Note: Only settable in the process environment.
136
137                     Default: "/etc/mk.conf"
138
139     MAKEFLAGS       Flags to invoke make(1) with.
140
141                     Note: build.sh ignores the value of MAKEFLAGS passed in
142                     the environment, but allows MAKEFLAGS to be set via the
143                     -V option.
144
145     MAKEOBJDIR      Directory to use as the .OBJDIR for the current
146                     directory.  The value is subjected to variable expansion
147                     by make(1).  Typical usage is to set this variable to a
148                     value involving the use of `${.CURDIR:S...}' or
149                     `${.CURDIR:C...}', to derive the value of .OBJDIR from
150                     the value of .CURDIR.  Used only if MAKEOBJDIRPREFIX is
151                     not defined.
152
153                     Note: MAKEOBJDIR can be provided only in the environment
154                     or via the -O flag of build.sh; it cannot usefully be set
155                     inside a Makefile, including in mk.conf(5) or MAKECONF.
156
157     MAKEOBJDIRPREFIX
158                     Top level directory of the object directory tree.  The
159                     value is subjected to variable expansion by make(1).
160                     build.sh will create the ${MAKEOBJDIRPREFIX} directory if
161                     necessary, but if make(1) is used without build.sh, then
162                     rules in <bsd.obj.mk> will abort the build if the
163                     ${MAKEOBJDIRPREFIX} directory does not exist.  If the
164                     value is defined and valid, then
165                     ${MAKEOBJDIRPREFIX}/${.CURDIR} is used as the .OBJDIR for
166                     the current directory.  The current directory may be read
167                     only.
168
169                     Note: MAKEOBJDIRPREFIX can be provided only in the
170                     environment or via the -M flag of build.sh; it cannot
171                     usefully be set inside a Makefile, including in
172                     mk.conf(5) or MAKECONF.
173
174     TMPDIR          Top-level directory to store temporary directories used
175                     by build.sh before paths to other directories such as
176                     .OBJDIR can be determined.
177
178                     Note: Must support execution of binaries.  I.e., without
179                     mount(8)'s -o noexec option.
180
181                     Default: "/tmp".
182
183   "make" variables
184     Several variables control the behavior of NetBSD builds.  Unless
185     otherwise specified, these variables may be set in either the process
186     environment or the make(1) configuration file mk.conf(5) specified by
187     MAKECONF.
188
189     This list is not comprehensive; all supported variables and their
190     defaults are documented in mk.conf(5).
191
192     BSDOBJDIR       The real path to the object directory tree for the NetBSD
193                     source tree.
194
195                     Default: "/usr/obj"
196
197     BSDSRCDIR       The real path to the NetBSD source tree, if NETBSDSRCDIR
198                     isn't defined.
199
200                     Default: "/usr/src"
201
202     BUILDID         Identifier for the build.  If set, this should be a short
203                     string that is suitable for use as part of a file or
204                     directory name.  The identifier will be appended to
205                     object directory names, and can be consulted in the
206                     make(1) configuration file in order to set additional
207                     build parameters, such as compiler flags.  It will also
208                     be used as part of the kernel version string, which can
209                     be shown by "uname -v".
210
211                     Default: Unset.
212
213     BUILDINFO       Optional multi-line string containing information about
214                     the build.  This will appear in DESTDIR/etc/release, and
215                     it will be stored in the buildinfo variable in any
216                     kernels that are built.  When such kernels are booted,
217                     the sysctl(7) kern.buildinfo variable will report this
218                     value.  The string may contain backslash escape
219                     sequences, such as "\\" (representing a backslash
220                     character) and "\n" (representing a newline).
221
222                     Default: Unset.
223
224     BUILDSEED       g++(1) uses random numbers when compiling C++ code.  This
225                     variable seeds the g++(1) random number generator using
226                     -frandom-seed with this value.  By default, it is set to
227                     "NetBSD-(majorversion)".  Using a fixed value causes C++
228                     binaries to be the same when built from the same sources,
229                     resulting in identical (reproducible) builds.  Additional
230                     information is available in the g++(1) documentation of
231                     -frandom-seed.
232
233                     Default: Unset.
234
235     CPUFLAGS        Additional flags to the compiler/assembler to select CPU
236                     instruction set options, CPU tuning options, etc.
237
238                     Default: Unset.
239
240     DESTDIR         Directory to contain the built NetBSD system.  If set,
241                     special options are passed to the compilation tools to
242                     prevent their default use of the host system's
243                     /usr/include, /usr/lib, and so forth.  This pathname must
244                     be an absolute path, and should not end with a slash (/)
245                     character.  (For installation into the system's root
246                     directory, set DESTDIR to an empty string, not to "/").
247                     The directory must reside on a file system which supports
248                     long file names and hard links.
249
250                     Note: build.sh will provide a default of destdir.MACHINE
251                     (in the top-level .OBJDIR) unless run in `expert' mode.
252
253                     Default: Empty string if USETOOLS is "yes"; unset
254                     otherwise.
255
256     EXTERNAL_TOOLCHAIN
257                     If defined, this variable indicates the root directory of
258                     an external toolchain which will be used to build the
259                     tree.  For example, if a platform is a TOOLCHAIN_MISSING
260                     platform, EXTERNAL_TOOLCHAIN can be used to re-enable the
261                     cross-compile framework.
262
263                     If EXTERNAL_TOOLCHAIN is defined, act as MKGCC=no, since
264                     the external version of the compiler may not be able to
265                     build the library components of the in-tree compiler.
266
267                     This variable should be used in conjunction with an
268                     appropriate HAVE_GCC or HAVE_LLVM setting to control the
269                     compiler flags.
270
271                     Note: This variable is not yet used in as many places as
272                     it should be.  Expect the exact semantics of this
273                     variable to change in the short term as parts of the
274                     cross-compile framework continue to be cleaned up.
275
276                     Default: Unset.
277
278     MAKEVERBOSE     Level of verbosity of status messages.  Supported values:
279
280                     0   No descriptive messages or commands executed by
281                         make(1) are shown.
282
283                     1   Brief messages are shown describing what is being
284                         done, but the actual commands executed by make(1) are
285                         not shown.
286
287                     2   Descriptive messages are shown as above (prefixed
288                         with a `#'), and ordinary commands performed by
289                         make(1) are shown.
290
291                     3   In addition to the above, all commands performed by
292                         make(1) are shown, even if they would ordinarily have
293                         been hidden through use of the "@" prefix in the
294                         relevant makefile.
295
296                     4   In addition to the above, commands executed by
297                         make(1) are traced through use of the sh(1) "-x"
298                         flag.
299
300                     Default: 2
301
302     MKCATPAGES      Can be set to "yes" or "no".  Indicates whether
303                     preformatted plaintext manual pages will be created and
304                     installed.
305
306                     Forced to "no" if MKMAN=no or MKSHARE=no.
307
308                     Default: "no"
309
310     MKCROSSGDB      Can be set to "yes" or "no".  Create a cross-gdb as a
311                     host tool.
312
313                     Default: "no"
314
315     MKDEBUG         Can be set to "yes" or "no".  Indicates whether debug
316                     information should be generated for all userland
317                     binaries.  The result is collected as an additional
318                     debug.tgz and xdebug.tgz set and installed in
319                     DESTDIR/usr/libdata/debug.
320
321                     Forced to "no" if NODEBUG is defined, usually in the
322                     Makefile before any make(1) .include directives.
323
324                     Default: "no"
325
326     MKDEBUGKERNEL   Can be set to "yes" or "no".  Indicates whether debugging
327                     symbols will be built for kernels by default; pretend as
328                     if makeoptions DEBUG="-g" is specified in kernel
329                     configuration files.  This will also put the debug kernel
330                     netbsd.gdb in the kernel sets.  See options(4) for
331                     details.  This is useful if a cross-gdb is built as well
332                     (see MKCROSSGDB).
333
334                     Default: "no"
335
336     MKDEBUGLIB      Can be set to "yes" or "no".  Indicates whether debug
337                     libraries (lib*_g.a) will be built and installed.  Debug
338                     libraries are compiled with "-g -DDEBUG".
339
340                     Forced to "no" if NODEBUGLIB is defined, usually in the
341                     Makefile before any make(1) .include directives.
342
343                     Default: "no"
344
345     MKDEBUGTOOLS    Can be set to "yes" or "no".  Indicates whether debug
346                     information (lib*_g.a) will be included in the build
347                     toolchain.
348
349                     Default: "no"
350
351     MKDOC           Can be set to "yes" or "no".  Indicates whether system
352                     documentation destined for DESTDIR/usr/share/doc will be
353                     installed.
354
355                     Forced to "no" if NODOC is defined, usually in the
356                     Makefile before any make(1) .include directives.
357
358                     Forced to "no" if MKSHARE=no.
359
360                     Default: "yes"
361
362     MKHOSTOBJ       Can be set to "yes" or "no".  If set to "yes", then for
363                     programs intended to be run on the compile host, the
364                     name, release, and architecture of the host operating
365                     system will be suffixed to the name of the object
366                     directory created by "make obj".  (This allows multiple
367                     host systems to compile NetBSD for a single target.)  If
368                     set to "no", then programs built to be run on the compile
369                     host will use the same object directory names as programs
370                     built to be run on the target.
371
372                     Default: "no"
373
374     MKHTML          Can be set to "yes" or "no".  Indicates whether the HTML
375                     manual pages are created and installed.  and installed
376
377                     Forced to "no" if NOHTML is defined, usually in the
378                     Makefile before any make(1) .include directives.
379
380                     Forced to "no" if MKMAN=no or MKSHARE=no.
381
382                     Default: "yes"
383
384     MKINFO          Can be set to "yes" or "no".  Indicates whether GNU Info
385                     files, used for the documentation for most of the
386                     compilation tools, will be built and installed.
387
388                     Forced to "no" if NOINFO is defined, usually in the
389                     Makefile before any make(1) .include directives.
390
391                     Forced to "no" if MKSHARE=no.
392
393                     Default: "yes"
394
395     MKKDEBUG        Deprecated, use MKDEBUGKERNEL.
396
397     MKKMOD          Can be set to "yes" or "no".  Indicates whether kernel
398                     modules are built and installed.
399
400                     Default: "no" on or1k; "yes" on other platforms.
401
402     MKLINKLIB       Can be set to "yes" or "no".  Indicates whether all of
403                     the shared library infrastructure will be built and
404                     installed.  If "no", prevents: installation of the *.a
405                     libraries, installation of the *_pic.a libraries on PIC
406                     systems, building of *.a libraries on PIC systems, or
407                     installation of .so symlinks on ELF systems.
408
409                     Forced to "no" if NOLINKLIB is defined, usually in the
410                     Makefile before any make(1) .include directives.
411
412                     If "no", acts as MKLINT=no MKPICINSTALL=no MKPROFILE=no.
413
414                     Default: "yes"
415
416     MKLINT          Can be set to "yes" or "no".  Indicates whether lint(1)
417                     will be run against portions of the NetBSD source code
418                     during the build, and whether lint libraries will be
419                     installed into DESTDIR/usr/libdata/lint.
420
421                     Forced to "no" if NOLINT is defined, usually in the
422                     Makefile before any make(1) .include directives.
423
424                     Forced to "no" if MKLINKLIB=no.
425
426                     Default: "no"
427
428     MKMAN           Can be set to "yes" or "no".  Indicates whether manual
429                     pages will be installed.
430
431                     Forced to "no" if NOMAN is defined, usually in the
432                     Makefile before any make(1) .include directives.
433
434                     Forced to "no" if MKSHARE=no.
435
436                     If "no", acts as MKCATPAGES=no MKHTML=no.
437
438                     Default: "yes"
439
440     MKNLS           Can be set to "yes" or "no".  Indicates whether Native
441                     Language System (NLS) locale zone files will be built and
442                     installed.
443
444                     Forced to "no" if NONLS is defined, usually in the
445                     Makefile before any make(1) .include directives.
446
447                     Forced to "no" if MKSHARE=no.
448
449                     Default: "yes"
450
451     MKOBJ           Can be set to "yes" or "no".  Indicates whether object
452                     directories will be created when running "make obj".  If
453                     set to "no", then all built files will be located inside
454                     the regular source tree.
455
456                     Forced to "no" if NOOBJ is defined, usually in the
457                     Makefile before any make(1) .include directives.
458
459                     If "no", acts as MKOBJDIRS=no.
460
461                     Note: Setting MKOBJ to "no" is not recommended and may
462                     cause problems when updating the tree with cvs(1).
463
464                     Default: "yes"
465
466     MKOBJDIRS       Can be set to "yes" or "no".  Indicates whether object
467                     directories will be created automatically (via a "make
468                     obj" pass) at the start of a build.
469
470                     Forced to "no" if MKOBJ=no.
471
472                     Default: "no"
473
474     MKPIC           Can be set to "yes" or "no".  Indicates whether shared
475                     objects and libraries will be created and installed.  If
476                     "no", the entire built system will be statically linked.
477
478                     Forced to "no" if NOPIC is defined, usually in the
479                     Makefile before any make(1) .include directives.
480
481                     If "no", acts as MKPICLIB=no.
482
483                     Default: "no" on m68000; "yes" on other platforms.
484
485     MKPICINSTALL    Can be set to "yes" or "no".  Indicates whether the ar(1)
486                     format libraries (lib*_pic.a), used to generate shared
487                     libraries, are installed.
488
489                     Forced to "no" if NOPICINSTALL is defined, usually in the
490                     Makefile before any make(1) .include directives.
491
492                     Forced to "no" if MKLINKLIB=no.
493
494                     Default: "no"
495
496     MKPROFILE       Can be set to "yes" or "no".  Indicates whether profiled
497                     libraries (lib*_p.a) will be built and installed.
498
499                     Forced to "no" if NOPROFILE is defined, usually in the
500                     Makefile before any make(1) .include directives.
501
502                     Forced to "no" if MKLINKLIB=no.
503
504                     Default: "no" on or1k, riscv32, and riscv64 (due to
505                     toolchain problems with profiled code); "yes" on other
506                     platforms.
507
508     MKREPRO         Can be set to "yes" or "no".  Indicates whether builds
509                     are to be reproducible.  If "yes", two builds from the
510                     same source tree will produce the same build results.
511
512                     Used as the default for MKARZERO.
513
514                     This may be set to "yes" by giving build.sh the -P
515                     option.
516
517                     Default: "no" Can be set to "yes" or "no".
518
519     MKREPRO_TIMESTAMP
520                     Unix timestamp.  When MKREPRO is set, the timestamp of
521                     all files in the sets will be set to this value.
522
523                     This may be set automatically to the latest source tree
524                     timestamp using cvslatest(1) by giving build.sh the -P
525                     option.
526
527                     Default: Unset.
528
529     MKSHARE         Can be set to "yes" or "no".  Indicates whether files
530                     destined to reside in DESTDIR/usr/share will be built and
531                     installed.
532
533                     Forced to "no" if NOSHARE is defined, usually in the
534                     Makefile before any make(1) .include directives.
535
536                     If "no", acts as MKCATPAGES=no MKDOC=no MKINFO=no
537                     MKHTML=no MKMAN=no MKNLS=no.
538
539                     Default: "yes"
540
541     MKSTRIPIDENT    Can be set to "yes" or "no".  Indicates whether RCS IDs,
542                     for use with ident(1), should be stripped from program
543                     binaries and shared libraries.
544
545                     Default: "no"
546
547     MKSTRIPSYM      Can be set to "yes" or "no".  Indicates whether all local
548                     symbols should be stripped from shared libraries.  If
549                     "yes", strip all local symbols from shared libraries; the
550                     affect is equivalent to the -x option of ld(1).  If "no",
551                     strip only temporary local symbols; the affect is
552                     equivalent to the -X option of ld(1).  Keeping non-
553                     temporary local symbols such as static function names is
554                     useful on using DTrace for userland libraries and getting
555                     a backtrace from a rump kernel loading shared libraries.
556
557                     Default: "yes"
558
559     MKUNPRIVED      Can be set to "yes" or "no".  Indicates whether an
560                     unprivileged install will occur.  The user, group,
561                     permissions, and file flags, will not be set on the
562                     installed items; instead the information will be appended
563                     to a file called METALOG in DESTDIR.  The contents of
564                     METALOG are used during the generation of the
565                     distribution tar files to ensure that the appropriate
566                     file ownership is stored.
567
568                     Default: "no"
569
570     MKUPDATE        Can be set to "yes" or "no".  Indicates whether all
571                     install operations intended to write to DESTDIR will
572                     compare file timestamps before installing, and skip the
573                     install phase if the destination files are up-to-date.
574
575                     Note: This also has implications on full builds (see next
576                     subsection).
577
578                     Default: "no"
579
580     MKX11           Can be set to "yes" or "no".  Indicates whether X11 is
581                     built and installed from X11SRCDIR, and whether the X
582                     sets will be created.
583
584                     Note: If "yes", requires MKINET6=yes.
585
586                     Default: "no"
587
588     NETBSDSRCDIR    The path to the top level of the NetBSD sources.
589
590                     Default: Top level of the NetBSD source tree (as
591                     determined by the presence of build.sh and tools/) if
592                     make(1) is run from within that tree; otherwise BSDSRCDIR
593                     will be used.
594
595     TOOLCHAIN_MISSING
596                     Can be set to "yes" or "no".  If not "no", this indicates
597                     that the platform "MACHINE_ARCH" being built does not
598                     have a working in-tree toolchain.
599
600                     If not "no", acts as MKBINUTILS=no MKGCC=no MKGDB=no.
601
602                     Default: "no"
603
604     TOOLDIR         Directory to hold the host tools, once built.  If
605                     specified, must be an absolute path.  This directory
606                     should be unique to a given host system and NetBSD source
607                     tree.  (However, multiple targets may share the same
608                     TOOLDIR; the target-dependent files have unique names.)
609                     If unset, a default based on the uname(1) information of
610                     the host platform will be created in the .OBJDIR of src.
611
612                     Default: Unset.
613
614     USETOOLS        Can be set to "yes" or "no".  Indicates whether the tools
615                     specified by TOOLDIR should be used as part of a build in
616                     progress.  Must be set to "yes" if cross-compiling.
617
618                     yes    Use the tools from TOOLDIR.
619
620                     no     Do not use the tools from TOOLDIR, but refuse to
621                            build native compilation tool components that are
622                            version-specific for that tool.
623
624                     never  Do not use the tools from TOOLDIR, even when
625                            building native tool components.  This is similar
626                            to the traditional NetBSD build method, but does
627                            not verify that the compilation tools in use are
628                            up-to-date enough in order to build the tree
629                            successfully.  This may cause build or runtime
630                            problems when building the whole NetBSD source
631                            tree.
632
633                     Default: "no" when using <bsd.*.mk> outside the NetBSD
634                     source tree (detected automatically) or if
635                     TOOLCHAIN_MISSING=yes; "yes" otherwise.
636
637     X11SRCDIR       Directory containing the modular Xorg source.  If
638                     specified, must be an absolute path.  The main modular
639                     Xorg source is found in X11SRCDIR/external/mit.
640
641                     Default: NETBSDSRCDIR/../xsrc, if that exists; otherwise
642                     /usr/xsrc.
643
644   "make" variables for full builds
645     These variables only affect the top level "Makefile" and do not affect
646     manually building subtrees of the NetBSD source code.
647
648     INSTALLBOOT_BOARDS
649                     A list of boards to create bootable images for.  If
650                     corresponding U-Boot packages are installed, bootable
651                     images are created as part of a release.  See the
652                     -o board=name option of installboot(8).
653
654     INSTALLWORLDDIR
655                     Location for the "make installworld" target to install
656                     to.  If specified, must be an absolute path.
657
658                     Default: "/"
659
660     MKOBJDIRS       Can be set to "yes" or "no".  Indicates whether object
661                     directories will be created automatically (via a "make
662                     obj" pass) at the start of a build.
663
664                     Default: "no"
665
666                     If using build.sh, the default is "yes".  This may be set
667                     back to "no" by giving build.sh the -o option.
668
669     MKUPDATE        Can be set to "yes" or "no".  If set, then in addition to
670                     the effects described for MKUPDATE=yes above, this
671                     implies the effects of NOCLEANDIR (i.e., "make cleandir"
672                     is avoided).
673
674                     Default: "no"
675
676                     If using build.sh, this may be set by giving the -u
677                     option.
678
679     NBUILDJOBS      Now obsolete.  Use the make(1) option -j, instead.  See
680                     below.
681
682                     Default: Unset.
683
684     NOCLEANDIR      If set, avoids the "make cleandir" phase of a full build.
685                     This has the effect of allowing only changed files in a
686                     source tree to be recompiled.  This can speed up builds
687                     when updating only a few files in the tree.
688
689                     Default: Unset.
690
691                     See also MKUPDATE.
692
693     NODISTRIBDIRS   If set, avoids the "make distrib-dirs" phase of a full
694                     build.  This skips running mtree(8) on DESTDIR, useful on
695                     systems where building as an unprivileged user, or where
696                     it is known that the system-wide mtree files have not
697                     changed.
698
699                     Default: Unset.
700
701     NOINCLUDES      If set, avoids the "make includes" phase of a full build.
702                     This has the effect of preventing make(1) from thinking
703                     that some programs are out-of-date simply because the
704                     system include files have changed.  However, this option
705                     should not be used when updating the entire NetBSD source
706                     tree arbitrarily; it is suggested to use MKUPDATE=yes
707                     instead in that case.
708
709                     Default: Unset.
710
711     RELEASEDIR      If set, specifies the directory to which a release(7)
712                     layout will be written at the end of a "make release".
713                     If specified, must be an absolute path.
714
715                     Note: build.sh will provide a default of releasedir (in
716                     the top-level .OBJDIR) unless run in `expert' mode.
717
718                     Default: Unset.
719
720BUILDING
721   "make" command line options
722     This is not a summary of all the options available to make(1); only the
723     options used most frequently with NetBSD builds are listed here.
724
725     -j njob    Run up to njob make(1) subjobs in parallel.  Makefiles should
726                use .WAIT or have explicit dependencies as necessary to
727                enforce build ordering.
728
729     -m dir     Specify the default directory for searching for system
730                Makefile segments, mainly the <bsd.*.mk> files.  When building
731                any full NetBSD source tree, this should be set to the
732                "share/mk" directory in the source tree.  This is set
733                automatically when building from the top level, or when using
734                build.sh.
735
736     -n         Show the commands that would have been executed, but do not
737                actually execute them.  This will still cause recursion to
738                take place.
739
740     -V var     Show make(1)'s idea of the value of var.  Does not build any
741                targets.
742
743     var=value  Set the variable var to value, overriding any setting
744                specified by the process environment, the MAKECONF
745                configuration file, or the system Makefile segments.
746
747   "make" targets
748     These default targets may be built by running make(1) in any subtree of
749     the NetBSD source code.  It is recommended that none of these be used
750     from the top level Makefile; as a specific exception, "make obj" and
751     "make cleandir" are useful in that context.
752
753     all        Build programs, libraries, and preformatted documentation.
754
755     clean      Remove program and library object code files.
756
757     cleandir   Same as clean, but also remove preformatted documentation,
758                dependency files generated by "make depend", and any other
759                files known to be created at build time.
760
761     depend     Create dependency files (.depend) containing more detailed
762                information about the dependencies of source code on header
763                files.  Allows programs to be recompiled automatically when a
764                dependency changes.
765
766     dependall  Does a "make depend" immediately followed by a "make all".
767                This improves cache locality of the build since both passes
768                read the source files in their entirety.
769
770     distclean  Synonym for cleandir.
771
772     includes   Build and install system header files.  Typically needed
773                before any system libraries or programs can be built.
774
775     install    Install programs, libraries, and documentation into DESTDIR.
776                Few files will be installed to DESTDIR/dev, DESTDIR/etc,
777                DESTDIR/root or DESTDIR/var in order to prevent user supplied
778                configuration data from being overwritten.
779
780     lint       Run lint(1) against the C source code, where appropriate, and
781                generate system-installed lint libraries.
782
783     obj        Create object directories to be used for built files, instead
784                of building directly in the source tree.
785
786     tags       Create ctags(1) searchable function lists usable by the ex(1)
787                and vi(1) text editors.
788
789   "make" targets for the top level
790     Additional make(1) targets are usable specifically from the top source
791     level to facilitate building the entire NetBSD source tree.
792
793     build         Build the entire NetBSD system (except the kernel).  This
794                   orders portions of the source tree such that prerequisites
795                   will be built in the proper order.
796
797     distribution  Do a "make build", and then install a full distribution
798                   (which does not include a kernel) into DESTDIR, including
799                   files in DESTDIR/dev, DESTDIR/etc, DESTDIR/root and
800                   DESTDIR/var.
801
802     buildworld    As per "make distribution", except that it ensures that
803                   DESTDIR is not the root directory.
804
805     installworld  Install the distribution from DESTDIR to INSTALLWORLDDIR,
806                   which defaults to the root directory.  Ensures that
807                   INSTALLWORLDDIR is not the root directory if cross
808                   compiling.
809
810                   The INSTALLSETS environment variable may be set to a space-
811                   separated list of distribution sets to be installed.  By
812                   default, all sets except "etc" and "xetc" are installed, so
813                   most files in INSTALLWORLDDIR/etc will not be installed or
814                   modified.
815
816                   Note: Before performing this operation with
817                   INSTALLWORLDDIR=/, it is highly recommended that you
818                   upgrade your kernel and reboot.  After performing this
819                   operation, it is recommended that you use etcupdate(8) to
820                   update files in INSTALLWORLDDIR/etc, and postinstall(8) to
821                   check for or fix inconsistencies.
822
823     sets          Create distribution sets from DESTDIR into
824                   RELEASEDIR/RELEASEMACHINEDIR/binary/sets.  Should be run
825                   after "make distribution", as "make build" alone does not
826                   install all of the required files.
827
828     sourcesets    Create source sets of the source tree into
829                   RELEASEDIR/source/sets.
830
831     syspkgs       Create syspkgs from DESTDIR into
832                   RELEASEDIR/RELEASEMACHINEDIR/binary/syspkgs.  Should be run
833                   after "make distribution", as "make build" alone does not
834                   install all of the required files.
835
836     release       Do a "make distribution", build kernels, distribution
837                   media, and install sets (this as per "make sets"), and then
838                   package the system into a standard release layout as
839                   described by release(7).  This requires that RELEASEDIR be
840                   set (see above).
841
842     iso-image     Create a NetBSD installation CD-ROM image in the
843                   RELEASEDIR/images directory.  The CD-ROM file system will
844                   have a layout as described in release(7).
845
846                   For most machine types, the CD-ROM will be bootable, and
847                   will automatically run the sysinst(8) menu-based
848                   installation program, which can be used to install or
849                   upgrade a NetBSD system.  Bootable CD-ROMs also contain
850                   tools that may be useful in repairing a damaged NetBSD
851                   installation.
852
853                   Before "make iso-image" is attempted, RELEASEDIR must be
854                   populated by "make release" or equivalent.
855
856                   Note: Other, smaller, CD-ROM images may be created in the
857                   RELEASEDIR/RELEASEMACHINEDIR/installation/cdrom directory
858                   by "make release".  These smaller images usually contain
859                   the same tools as the larger images in RELEASEDIR/images,
860                   but do not contain additional content such as the
861                   distribution sets.
862
863                   Note: The mac68k port still uses an older method of
864                   creating CD-ROM images.  This requires the mkisofs(1)
865                   utility, which is not part of NetBSD, but which can be
866                   installed from pkgsrc/sysutils/cdrtools.
867
868     iso-image-source
869                   Create a NetBSD installation CD-ROM image in the
870                   RELEASEDIR/images directory.  The CD-ROM file system will
871                   have a layout as described in release(7).  It will have top
872                   level directories for the machine type and source.
873
874                   For most machine types, the CD-ROM will be bootable, and
875                   will automatically run the sysinst(8) menu-based
876                   installation program, which can be used to install or
877                   upgrade a NetBSD system.  Bootable CD-ROMs also contain
878                   tools that may be useful in repairing a damaged NetBSD
879                   installation.
880
881                   Before "make iso-image-source" is attempted, RELEASEDIR
882                   must be populated by "make sourcesets release" or
883                   equivalent.
884
885                   Note: Other, smaller, CD-ROM images may be created in the
886                   RELEASEDIR/RELEASEMACHINEDIR/installation/cdrom directory
887                   by "make release".  These smaller images usually contain
888                   the same tools as the larger images in RELEASEDIR/images,
889                   but do not contain additional content such as the
890                   distribution sets.
891
892                   Note: The mac68k port still uses an older method of
893                   creating CD-ROM images.  This requires the mkisofs(1)
894                   utility, which is not part of NetBSD, but which can be
895                   installed from pkgsrc/sysutils/cdrtools.
896
897     install-image
898                   Create a bootable NetBSD installation disk image in the
899                   RELEASEDIR/images directory.  The installation disk image
900                   is suitable for copying to bootable USB flash memory
901                   sticks, etc., for machines which are able to boot from such
902                   devices.  The file system in the bootable disk image will
903                   have a layout as described in release(7).
904
905                   The installation image is bootable, and will automatically
906                   run the sysinst(8) menu-based installation program, which
907                   can be used to install or upgrade a NetBSD system.  The
908                   image also contains tools that may be useful in repairing a
909                   damaged NetBSD installation.
910
911                   Before "make install-image" is attempted, RELEASEDIR must
912                   be populated by "make release" or equivalent.  The build
913                   must have been performed with MKUNPRIVED=yes because "make
914                   install-image" relies on information in DESTDIR/METALOG.
915
916     live-image    Create NetBSD live images in the RELEASEDIR/images
917                   directory.  The live image contains all necessary files to
918                   boot NetBSD up to multi-user mode, including all files
919                   which should be extracted during installation, NetBSD
920                   disklabel, bootloaders, etc.
921
922                   The live image is suitable for use as a disk image in
923                   virtual machine environments such as QEMU, and also useful
924                   to boot NetBSD from a USB flash memory stick on a real
925                   machine, without the need for installation.
926
927                   Before "make live-image" is attempted, RELEASEDIR must be
928                   populated by "make release" or equivalent.  The build must
929                   have been performed with MKUNPRIVED=yes because "make
930                   install-image" relies on information in DESTDIR/METALOG.
931
932     regression-tests
933                   Can only be run after building the regression tests in the
934                   directory "regress".  Runs those compiled regression tests
935                   on the local host.
936
937                   Note: Most tests are now managed instead using atf(7); this
938                   target should probably run those as well but currently does
939                   not.
940
941   The "build.sh" script
942     This script file is a shell script designed to build the entire NetBSD
943     system on any host with a suitable modern shell and some common
944     utilities.  The required shell features are described under the HOST_SH
945     variable.
946
947     If a host system's default shell does support the required features, then
948     we suggest that you explicitly specify a suitable shell using a command
949     like
950
951           /path/to/suitable/shell build.sh [options]
952
953     The above command will usually enable build.sh to automatically set
954     HOST_SH=/path/to/suitable/shell, but if that fails, then the following
955     set of commands may be used instead:
956
957           HOST_SH=/path/to/suitable/shell
958           export HOST_SH
959           ${HOST_SH} build.sh [options]
960
961     If build.sh detects that it is being executed under an unsuitable shell,
962     it attempts to exec a suitable shell instead, or shows an error message.
963     If HOST_SH is not set explicitly, then build.sh sets a default using
964     heuristics dependent on the host platform, or from the shell under which
965     build.sh is executed (if that can be determined), or using the first copy
966     of sh found in PATH.
967
968     All cross-compile builds, and most native builds, of the entire system
969     should make use of build.sh rather than just running "make".  This way,
970     the make(1) program will be bootstrapped properly, in case the host
971     system has an older or incompatible "make" program.
972
973     When compiling the entire system via build.sh, many make(1) variables are
974     set for you in order to help encapsulate the build process.  In the list
975     of options below, variables that are automatically set by build.sh are
976     noted where applicable.
977
978     The following operations are supported by build.sh:
979
980     build         Build the system as per "make build".  Before the main part
981                   of the build commences, this command runs the obj operation
982                   (unless the -o option is given), "make cleandir" (unless
983                   the -u option is given), and the tools operation.
984
985     distribution  Build a full distribution as per "make distribution".  This
986                   command first runs the build operation.
987
988     release       Build a full release as per "make release".  This command
989                   first runs the distribution operation.
990
991     help          Show a help message, and exit.
992
993     makewrapper   Create the nbmake-MACHINE wrapper.  This operation is
994                   automatically performed for any of the other operations.
995
996     cleandir      Perform "make cleandir".
997
998     obj           Perform "make obj".
999
1000     tools         Build and install the host tools from src/tools.  This
1001                   command will first run "make obj" and "make cleandir" in
1002                   the tools subdirectory unless the -o or -u options
1003                   (respectively) are given.
1004
1005     install=idir  Install the contents of DESTDIR to idir, using "make
1006                   installworld".
1007
1008                   Note: Files that are part of the "etc" or "xetc" sets will
1009                   not be installed, unless overridden by the INSTALLSETS
1010                   environment variable.
1011
1012     kernel=kconf  Build a new kernel.  The kconf argument is the name of a
1013                   configuration file suitable for use by config(1).  If kconf
1014                   does not contain any `/' characters, the configuration file
1015                   is expected to be found in the KERNCONFDIR directory, which
1016                   is typically sys/arch/MACHINE/conf.  The new kernel will be
1017                   built in a subdirectory of KERNOBJDIR, which is typically
1018                   sys/arch/MACHINE/compile or an associated object directory.
1019
1020                   This command does not imply the tools command; run the
1021                   tools command first unless it is certain that the tools
1022                   already exist and are up to date.
1023
1024                   This command will run "make cleandir" on the kernel in
1025                   question first unless the -u option is given.
1026
1027     kernel.gdb=kconf
1028                   Build a new kernel with debug information.  Similar to the
1029                   above kernel=kconf operation, but creates a netbsd.gdb file
1030                   alongside of the kernel netbsd, which contains a full
1031                   symbol table and can be used for debugging (for example
1032                   with a cross-gdb built by MKCROSSGDB).
1033
1034     kernels       This command will build all kernels defined in port
1035                   specific release build procedure.
1036
1037                   This command internally calls the kernel=kconf operation
1038                   for each found kernel configuration file.
1039
1040     modules       This command will build kernel modules and install them
1041                   into DESTDIR.
1042
1043     releasekernel=kconf
1044                   Install a gzip(1)ed copy of the kernel previously built by
1045                   kernel=kconf into
1046                   RELEASEDIR/RELEASEMACHINEDIR/binary/kernel, usually as
1047                   netbsd-kconf.gz, although the "netbsd" prefix is determined
1048                   from the "config" directives in kconf.
1049
1050     sets          Perform "make sets".
1051
1052     sourcesets    Perform "make sourcesets".
1053
1054     syspkgs       Perform "make syspkgs".
1055
1056     iso-image     Perform "make iso-image".
1057
1058     iso-image-source
1059                   Perform "make iso-image-source".
1060
1061     install-image
1062                   Perform "make install-image".
1063
1064     live-image    Perform "make live-image".
1065
1066     list-arch     Show a list of valid MACHINE and MACHINE_ARCH settings, the
1067                   default MACHINE_ARCH for each MACHINE, and aliases for
1068                   MACHINE/MACHINE_ARCH pairs, and then exits.  The -m or -a
1069                   options (or both) may be used to specify glob patterns that
1070                   will be used to narrow the list of results; for example,
1071                   "build.sh -m 'evb*' -a '*arm*' list-arch" will list all
1072                   known MACHINE/MACHINE_ARCH values in which either MACHINE
1073                   or ALIAS matches the pattern `evb*', and MACHINE_ARCH
1074                   matches the pattern `*arm*'.
1075
1076     The following command line options alter the behaviour of the build.sh
1077     operations described above:
1078
1079     -a arch   Set the value of MACHINE_ARCH to arch.  See the -m option for
1080               more information.
1081
1082     -B buildid
1083               Set the value of BUILDID to buildid.  This will also append the
1084               build identifier to the name of the "make" wrapper script so
1085               that the resulting name is of the form
1086               "nbmake-MACHINE-BUILDID".
1087
1088     -C cdextras
1089               Append cdextras to the CDEXTRA variable, which is a space-
1090               separated list of files or directories that will be added to
1091               the CD-ROM image that may be create by the "iso-image" or
1092               "iso-image-source" operations.  Files will be added to the root
1093               of the CD-ROM image, whereas directories will be copied
1094               recursively.  If relative paths are specified, they will be
1095               converted to absolute paths before being used.  Multiple paths
1096               may be specified via multiple -C options, or via a single
1097               option whose argument contains multiple space-separated paths.
1098
1099     -c compiler
1100               Select the compiler for the toolchain to build NetBSD and for
1101               inclusion in the NetBSD distribution.  Supported choices:
1102
1103                     clang
1104
1105                     gcc [default]
1106
1107               The compiler used to build the toolchain can be different; see
1108               HOST_CC and HOST_CXX.
1109
1110     -D dest   Set the value of DESTDIR to dest.  If a relative path is
1111               specified, it will be converted to an absolute path before
1112               being used.
1113
1114     -E        Set `expert' mode.  This overrides various sanity checks, and
1115               allows: DESTDIR does not have to be set to a non-root path for
1116               builds, and MKUNPRIVED=yes does not have to be set when
1117               building as a non-root user.
1118
1119               Note: It is highly recommended that you know what you are doing
1120               when you use this option.
1121
1122     -h        Show a help message, and exit.
1123
1124     -j njob   Run up to njob make(1) subjobs in parallel; passed through to
1125               make(1).  If you see failures for reasons other than running
1126               out of memory while using build.sh with -j, please save
1127               complete build logs so the failures can be analyzed.
1128
1129               To achieve the fastest builds, -j values between (1 + the
1130               number of CPUs) and (2 * the number of CPUs) are recommended.
1131               Use lower values on machines with limited memory or I/O
1132               bandwidth.
1133
1134     -M obj    Set MAKEOBJDIRPREFIX to obj.  Unsets MAKEOBJDIR.  See "-O obj"
1135               for more information.
1136
1137               For instance, if the source directory is /usr/src, a setting of
1138               "-M /usr/obj" will place build-time files under
1139               /usr/obj/usr/src/bin, /usr/obj/usr/src/lib,
1140               /usr/obj/usr/src/usr.bin, and so forth.
1141
1142               If a relative path is specified, it will be converted to an
1143               absolute path before being used.  build.sh imposes the
1144               restriction that the argument to the -M option must not begin
1145               with a "$" (dollar sign) character; otherwise it would be too
1146               difficult to determine whether the value is an absolute or a
1147               relative path.  If the directory does not already exist,
1148               build.sh will create it.
1149
1150     -m mach   Set the value of MACHINE to mach, unless the mach argument is
1151               an alias that refers to a MACHINE/MACHINE_ARCH pair, in which
1152               case both MACHINE and MACHINE_ARCH are set from the alias.
1153               Such aliases are interpreted entirely by build.sh; they are not
1154               used by any other part of the build system.  The MACHINE_ARCH
1155               setting implied by mach will override any value of MACHINE_ARCH
1156               in the process environment, but will not override a value set
1157               by the -a option.  All cross builds require -m, but if unset on
1158               a NetBSD host, the host's value of MACHINE will be detected and
1159               used automatically.
1160
1161               See the list-arch operation for a way to get a list of valid
1162               MACHINE and MACHINE_ARCH settings.
1163
1164     -N noiselevel
1165               Set the "noisyness" level of the build, by setting MAKEVERBOSE
1166               to noiselevel.
1167
1168     -n        Show the commands that would be executed by build.sh, but do
1169               not make any changes.  This is similar in concept to "make -n".
1170
1171     -O obj    Create an appropriate transform macro for MAKEOBJDIR that will
1172               place the built object files under obj.  Unsets
1173               MAKEOBJDIRPREFIX.
1174
1175               For instance, a setting of "-O /usr/obj" will place build-time
1176               files under /usr/obj/bin, /usr/obj/lib, /usr/obj/usr.bin, and
1177               so forth.
1178
1179               If a relative path is specified, it will be converted to an
1180               absolute path before being used.  build.sh imposes the
1181               restriction that the argument to the -O option must not contain
1182               a "$" (dollar sign) character.  If the directory does not
1183               already exist, build.sh will create it.
1184
1185               In normal use, exactly one of the -M or -O options should be
1186               specified.  If neither -M nor -O is specified, then a default
1187               object directory will be chosen according to rules in
1188               <bsd.obj.mk>.  Relying on this default is not recommended
1189               because it is determined by complex rules that are influenced
1190               by the values of several variables and by the location of the
1191               source directory.
1192
1193               Note: Placing the obj directory location outside of the default
1194               source tree hierarchy makes it easier to manually clear out old
1195               files in the event the "make cleandir" operation is unable to
1196               do so.  (See CAVEATS below.)
1197
1198               Note: The use of one of -M or -O is the only means of building
1199               multiple machine architecture userlands from the same source
1200               tree without cleaning between builds (in which case, one would
1201               specify distinct obj locations for each).
1202
1203     -o        Set the value of MKOBJDIRS to "no".  Otherwise, it will be
1204               automatically set to "yes".  This default is opposite to the
1205               behaviour when not using build.sh.
1206
1207     -P        Set the value of MKREPRO and MKREPRO_TIMESTAMP to the latest
1208               source CVS timestamp for reproducible builds.
1209
1210     -R rel    Set the value of RELEASEDIR to rel.  If a relative path is
1211               specified, it will be converted to an absolute path before
1212               being used.
1213
1214     -r        Remove the contents of DESTDIR and TOOLDIR before building
1215               (provides a clean starting point).  This will skip deleting
1216               DESTDIR if building on a native system to the root directory.
1217
1218     -S seed   Change the value of BUILDSEED to seed.  This should rarely be
1219               necessary.
1220
1221     -T tools  Set the value of TOOLDIR to tools.  If a relative path is
1222               specified, it will be converted to an absolute path before
1223               being used.  If set, the bootstrap "make" will only be rebuilt
1224               if the source files for make(1) have changed.
1225
1226     -U        Set MKUNPRIVED=yes.
1227
1228     -u        Set MKUPDATE=yes.
1229
1230     -V var=[value]
1231               Set the environment variable var to an optional value.  This is
1232               propagated to the nbmake wrapper.
1233
1234     -w wrapper
1235               Create the nbmake wrapper script (see below) in a custom
1236               location, specified by wrapper.  This allows, for instance, to
1237               place the wrapper in PATH automatically.
1238
1239               Note: wrapper is the full name of the file, not just a
1240               directory name.  If a relative path is specified, it will be
1241               converted to an absolute path before being used.
1242
1243     -X x11src
1244               Set the value of X11SRCDIR to x11src.  If a relative path is
1245               specified, it will be converted to an absolute path before
1246               being used.
1247
1248     -x        Set MKX11=yes.
1249
1250     -Z var    Unset ("zap") the environment variable var.  This is propagated
1251               to the nbmake wrapper.
1252
1253     -?        Show a help message, and exit.
1254
1255   The "nbmake-MACHINE" wrapper script
1256     If using the build.sh script to build NetBSD, a nbmake-MACHINE script
1257     will be created in TOOLDIR/bin upon the first build to assist in building
1258     subtrees on a cross-compile host.
1259
1260     nbmake-MACHINE can be invoked in lieu of make(1), and will instead call
1261     the up-to-date version of "nbmake" installed into TOOLDIR/bin with
1262     several key variables pre-set, including MACHINE, MACHINE_ARCH, and
1263     TOOLDIR.  nbmake-MACHINE will also set variables specified with -V, and
1264     unset variables specified with -Z.
1265
1266     This script can be symlinked into a directory listed in PATH, or called
1267     with an absolute path.
1268
1269EXAMPLES
1270     1.   % ./build.sh [OPTIONS] tools kernel=GENERIC
1271
1272          Build a new toolchain, and use the new toolchain to configure and
1273          build a new GENERIC kernel.
1274
1275     2.   % ./build.sh [OPTIONS] -U distribution
1276
1277          Using unprivileged mode, build a complete distribution to a DESTDIR
1278          directory that build.sh selects (and will show).
1279
1280     3.   # ./build.sh [OPTIONS] -U install=/
1281
1282          As root, install to / the distribution that was built by example 2.
1283          Even though this is run as root, -U is required so that the
1284          permissions stored in DESTDIR/METALOG are correctly applied to the
1285          files as they're copied to /.
1286
1287     4.   % ./build.sh [OPTIONS] -U -u release
1288
1289          Using unprivileged mode, build a complete release to DESTDIR and
1290          RELEASEDIR directories that build.sh selects (and will show).
1291          MKUPDATE=yes (-u) is set to prevent the "make cleandir", so that if
1292          this is run after example 2, it doesn't need to redo that portion of
1293          the release build.
1294
1295OBSOLETE VARIABLES
1296     NBUILDJOBS  Use the make(1) option -j instead.
1297
1298     USE_NEW_TOOLCHAIN
1299                 The new toolchain is now the default.  To disable, use
1300                 TOOLCHAIN_MISSING=yes.
1301
1302SEE ALSO
1303     ar(1), config(1), ctags(1), cvs(1), cvslatest(1), ex(1), g++(1), gzip(1),
1304     ident(1), ld(1), lint(1), make(1), mkisofs(1), sh(1), uname(1), vi(1),
1305     options(4), mk.conf(5), atf(7), hier(7), release(7), sysctl(7),
1306     etcupdate(8), installboot(8), mount(8), mtree(8), postinstall(8),
1307     sysinst(8), pkgsrc/sysutils/cdrtools
1308
1309HISTORY
1310     The build.sh based build scheme was introduced for NetBSD 1.6 as
1311     USE_NEW_TOOLCHAIN, and re-worked to TOOLCHAIN_MISSING after that.
1312
1313CAVEATS
1314     After significant updates to third-party components in the source tree,
1315     the "make cleandir" operation may be insufficient to clean out old files
1316     in object directories.  Instead, one may have to manually remove the
1317     files.  Consult the UPDATING file for notices concerning this.
1318
1319NetBSD                           June 5, 2023                           NetBSD
1320