BUILDING revision 1.8
1BUILDING(8)             NetBSD System Manager's Manual             BUILDING(8)
2
3NAME
4     BUILDING - Procedure for building NetBSD from source code.
5
6STATUS
7     This document is a work-in-progress.  As such, the information described
8     here may not match the reality of the build system as of this writing.
9     Once this document is completely in sync with reality, this paragraph
10     will be removed.
11
12     Discrepancies between this documentation and the current reality of im-
13     plementation are noted specially, as with the note below:
14
15     Note: This document applies only to platforms which use the new toolchain
16     as indicated by the default setting of USE_NEW_TOOLCHAIN in <bsd.own.mk>.
17     Platforms which have not yet been switched to the new toolchain should
18     continue building traditionally, using the notes specified in the file
19     UPDATING.
20
21REQUIREMENTS
22     NetBSD is designed to be buildable on most POSIX-compliant host systems.
23     The basic build procedure is the same whether compiling natively (on the
24     same NetBSD architecture) or cross compiling (on another architecture or
25     OS).
26
27     This source tree contains a special subtree, ``tools'', which uses the
28     host system to create a build toolchain for the target architecture.  The
29     host system must have at least C and C++ compilers in order to create the
30     toolchain (make is not required); all other tools are created as part of
31     the NetBSD build process.
32
33           Note: A couple host toolchain components are not yet available in
34           the tools directory.  Also, some tools use non-POSIX, non-ANSI C
35           extensions and need to be standardized.  As a result, cross-compil-
36           ing from systems other than NetBSD is not currently supported.
37
38FILES
39   Source tree layout
40
41     BUILDING.mdoc  This document (in -mdoc troff format; the original copy).
42
43     BUILDING       This document (in plaintext).
44
45     Makefile       The main Makefile for NetBSD; should only be run for na-
46                    tive builds with an appropriately up-to-date version of
47                    NetBSD make(1).  (For building from out-of-date systems or
48                    on a non-native host, see the build.sh shell script.)
49
50     UPDATING       Special notes for updating from an earlier revision of
51                    NetBSD.  It is important to read this file before every
52                    build of an updated source tree.
53
54     build.sh       Bourne-compatible shell script used for building the host
55                    build tools and the NetBSD system from scratch.  Can be
56                    used for both native and cross builds, and should be used
57                    instead of make(1) for any source tree that is updated and
58                    recompiled regularly.
59
60     crypto/dist/, dist/, gnu/dist/
61                    Sources imported verbatim from third parties, without man-
62                    gling the existing build structure.  Other source trees in
63                    bin through usr.sbin use the NetBSD make(1) ``reachover''
64                    Makefile semantics when building these programs for a na-
65                    tive host.
66
67     distrib/, etc/
68                    Sources for items used when making a full release snap-
69                    shot, such as files installed in /etc on the destination
70                    system, boot media, and release notes.
71
72     regress/       Regression test harness.  Can be cross-compiled, but only
73                    run natively.
74
75     sys/           NetBSD kernel sources.
76
77     tools/         ``Reachover'' build structure for the host build tools.
78                    This has a special method of determining out-of-date sta-
79                    tus.
80
81     bin/ ... usr.sbin/
82                    Sources to the NetBSD userland (non-kernel) programs.  If
83                    any of these directories are missing, they will be skipped
84                    during the build.
85
86   Build tree layout
87     The NetBSD build tree is described in hier(7), and the release layout is
88     described in release(7).
89
90CONFIGURATION
91   Environment variables
92     Several environment variables control the behaviour of NetBSD builds.
93
94     MACHINE           Machine type.
95
96     MACHINE_ARCH      Machine architecture.
97
98     MAKE              Path name to invoke make(1) as.
99
100     MAKEFLAGS         Flags to invoke make(1) with.
101
102     MAKEOBJDIR        Directory to use as the .OBJDIR for the current direc-
103                       tory.  Used only if MAKEOBJDIRPREFIX is not defined.
104                       MAKEOBJDIR can only be provided in the environment.
105
106     MAKEOBJDIRPREFIX  Top level directory of the object directory tree.  If
107                       this is defined, ${MAKEOBJDIRPREFIX}/${.CURDIR} is used
108                       as the .OBJDIR for the current directory.  The current
109                       directory may be read only.  MAKEOBJDIRPREFIX can only
110                       be provided in the environment.
111
112   "make" variables
113     Several variables control the behavior of NetBSD builds.  Unless other-
114     wise specified, these variables may be set in either the process environ-
115     ment or the make(1) configuration file specified by MAKECONF.
116
117     DESTDIR     Directory to contain the built NetBSD system.  If set, spe-
118                 cial options are passed to the compilation tools to prevent
119                 their default use of the host system's /usr/include,
120                 /usr/lib, and so forth.  This pathname should not end with a
121                 slash (/) character (for installation into the system's root
122                 directory, set DESTDIR to an empty string).  The directory
123                 must reside on a file system which supports long file names
124                 and hard links.
125
126                 Default: Empty string if USETOOLS is ``yes''; unset other-
127                 wise.
128
129     MAKECONF    The name of the make(1) configuration file.  Only settable in
130                 the process environment.
131
132                 Default: ``/etc/mk.conf''
133
134     MKCATPAGES  Can be set to ``yes'' or ``no''.  Indicates whether prefor-
135                 matted plaintext manual pages will be created during a build.
136
137                 Default: ``yes''
138
139     MKCRYPTO    Can be set to ``yes'' or ``no''.  Indicates whether crypto-
140                 graphic code will be included in a build; provided for the
141                 benefit of countries that do not allow strong cryptography.
142                 Will not affect use of the standard low-security password en-
143                 cryption system, crypt(3).
144
145                 Default: ``yes''
146
147     MKDOC       Can be set to ``yes'' or ``no''.  Indicates whether system
148                 documentation destined for /usr/share/doc will be installed
149                 during a build.
150
151                 Default: ``yes''
152
153     MKHOSTOBJ   Can be set to ``yes'' or ``no''.  If set to ``yes'', then for
154                 programs intended to be run on the compile host, the name,
155                 release, and architecture of the host operating system will
156                 be suffixed to the name of the object directory created by
157                 ``make obj''.  (This allows multiple host systems to compile
158                 NetBSD for a single target.)  If set to ``no'', then programs
159                 built to be run on the compile host will use the same object
160                 directory names as programs built to be run on the target.
161
162                 Default: ``no''
163
164     MKINFO      Can be set to ``yes'' or ``no''.  Indicates whether GNU Info
165                 files, used for the documentation for most of the compilation
166                 tools, will be created and installed during a build.
167
168                 Default: ``yes''
169
170     MKLINT      Can be set to ``yes'' or ``no''.  Indicates whether lint(1)
171                 will be run against portions of the NetBSD source code during
172                 the build, and whether lint libraries will be installed into
173                 /usr/libdata/lint.
174
175                 Default: ``yes''
176
177     MKMAN       Can be set to ``yes'' or ``no''.  Indicates whether manual
178                 pages will be installed during a build.
179
180                 Default: ``yes''
181
182     MKNLS       Can be set to ``yes'' or ``no''.  Indicates whether Native
183                 Language System locale zone files will be compiled and in-
184                 stalled during a build.
185
186                 Default: ``yes''
187
188     MKOBJ       Can be set to ``yes'' or ``no''.  Indicates whether object
189                 directories will be created when running ``make obj''.  If
190                 set to ``no'', then all built files will be located inside
191                 the regular source tree.
192
193                 Default: ``yes''
194
195     MKPIC       Can be set to ``yes'' or ``no''.  Indicates whether shared
196                 objects and libraries will be created and installed during a
197                 build.  If set to ``no'', the entire built system will be
198                 statically linked.
199
200                 Default: Platform dependent.  As of this writing, all plat-
201                 forms except sh3 default to ``yes''.
202
203     MKPICINSTALL
204                 Can be set to ``yes'' or ``no''.  Indicates whether the ar(1)
205                 format libraries (lib*_pic.a), used to generate shared li-
206                 braries, are installed during a build.
207
208                 Default: ``yes''
209
210     MKPROFILE   Can be set to ``yes'' or ``no''.  Indicates whether profiled
211                 libraries (lib*_p.a) will be built and installed during a
212                 build.
213
214                 Default: ``yes''; however, some platforms turn off MKPROFILE
215                 by default at times due to toolchain problems with profiled
216                 code.
217
218     MKSHARE     Can be set to ``yes'' or ``no''.  Indicates whether files
219                 destined to reside in /usr/share will be built and installed
220                 during a build.  If set to ``no'', then all of MKCATPAGES,
221                 MKDOC, MKINFO, MKMAN, and MKNLS will be set to ``no'' uncon-
222                 ditionally.
223
224                 Default: ``yes''
225
226     TOOLDIR     Directory to hold the host tools, once built.  This directory
227                 should be unique to a given host system and NetBSD source
228                 tree.  (However, multiple targets may share the same TOOLDIR;
229                 the target-dependent files have unique names.)  If unset, a
230                 default based on the uname(1) information of the host plat-
231                 form will be created in the .OBJDIR of src/tools.
232
233                 Default: Unset.
234
235     UNPRIVED    If set, then an unprivileged install will occur.  The user,
236                 group, permissions, and file flags, will not be set on the
237                 installed item; instead the information will be appended to a
238                 file called METALOG in the .OBJDIR of src.  The contents of
239                 METALOG is used during the generation of the distribution tar
240                 files to ensure that the appropriate file ownership is
241                 stored.
242
243                 Default: Unset.
244
245     UPDATE      If set, then all install operations intended to write to
246                 DESTDIR will compare file timestamps before installing, and
247                 skip the install phase if the destination files are up-to-
248                 date.  This also has implications on full builds (see next
249                 subsection).
250
251                 Default: Unset.
252
253     USETOOLS    Indicates whether the tools specified by TOOLDIR should be
254                 used as part of a build in progress.  Must be set to ``yes''
255                 if cross-compiling.
256
257                 yes    Use the tools from TOOLDIR.
258
259                 no     Do not use the tools from TOOLDIR, but refuse to build
260                        native compilation tool components that are version-
261                        specific for that tool.
262
263                 never  Do not use the tools from TOOLDIR, even when building
264                        native tool components.  This is similar to the tradi-
265                        tional NetBSD build method, but does not verify that
266                        the compilation tools in use are up-to-date enough in
267                        order to build the tree successfully.  This may cause
268                        build or runtime problems when building the whole
269                        NetBSD source tree.
270
271                 Default: ``yes'' if building all or part of a whole NetBSD
272                 source tree (detected automatically); ``no'' otherwise (to
273                 preserve traditional semantics of the <bsd.*.mk> make(1) in-
274                 clude files).
275
276   "make" variables for full builds
277     These variables only affect the top level ``Makefile'' and do not affect
278     manually building subtrees of the NetBSD source code.
279
280     MKOBJDIRS      Can be set to ``yes'' or ``no''.  Indicates whether object
281                    directories will be created automatically (via a ``make
282                    obj'' pass) at the start of a build.
283
284                    Default: ``yes''
285
286     NBUILDJOBS     If set, specifies the number of parallel make(1) processes
287                    that should be run simultaneously.  This can speed up
288                    builds on SMP machines, or machines with much more CPU
289                    power than I/O availability.  This should be used instead
290                    of the make(1) option -j, in order to ensure proper order-
291                    ing of build components.
292
293                    Default: Unset.
294
295     NOCLEANDIR     If set, avoids the ``make cleandir'' phase of a full
296                    build.  This has the effect of allowing only changed files
297                    in a source tree to be recompiled.  This can speed up
298                    builds when updating only a few files in the tree.
299
300                    Default: Unset.
301
302     NODISTRIBDIRS  If set, avoids the ``make distrib-dirs'' phase of a full
303                    build.  This skips running mtree(8) on DESTDIR, useful on
304                    systems where building as an unprivileged user, or where
305                    it is known that the system-wide mtree files have not
306                    changed.
307
308                    Default: Unset.
309
310     NOINCLUDES     If set, avoids the ``make includes'' phase of a full
311                    build.  This has the effect of preventing make(1) from
312                    thinking that some programs are out-of-date simply because
313                    the system include files have changed.  However, this op-
314                    tion should not be used when updating the entire NetBSD
315                    source tree arbitrarily; it is suggested to use UPDATE in
316                    that case.
317
318                    Default: Unset.
319
320     RELEASEDIR     If set, specifies the directory to which a release(7) lay-
321                    out will be written at the end of a ``make release''.
322
323                    Default: Unset.
324
325     UPDATE         If set, then in addition to the effects described for UP-
326                    DATE above, this implies the effects of NOCLEANDIR.
327
328BUILDING
329   "make" command line options
330     This is only a summary of options available to make(1); only the options
331     used most frequently with NetBSD builds are listed here.
332
333     -m dir     Specify the default directory for searching for system Make-
334                file segments, mainly the <bsd.*.mk> files.  When building any
335                full NetBSD source tree, this should be set to the
336                ``share/mk'' directory in the source tree.  (This is set auto-
337                matically when building from the top level.)
338
339     -n         Display the commands that would have been executed, but do not
340                actually execute them.  This will still cause recursion to
341                take place.
342
343     -v var     Print make(1)'s idea of the value of var.  Does not build any
344                targets.
345
346     var=value  Set the variable var to value, overriding any setting speci-
347                fied by the process environment, the MAKECONF configuration
348                file, or the system Makefile segments.
349
350   "make" targets
351     These default targets may be built by running make(1) in any subtree of
352     the NetBSD source code.  It is recommended that none of these be used
353     from the top level Makefile; as a specific exception, ``make obj'' and
354     ``make cleandir'' are useful in that context.
355
356     all        Build programs, libraries, and preformatted documentation.
357
358     clean      Remove program and library object code files.
359
360     cleandir   Same as clean, but also remove preformatted documentation, de-
361                pendency files generated by ``make depend'', and any other
362                files known to be created at build time.  ``make distclean''
363                may be used as a synonym, for familiarity with a similar well-
364                known convention.
365
366     depend     Create dependency files (.depend) containing more detailed in-
367                formation about the dependencies of source code on header
368                files.  Allows programs to be recompiled automatically when a
369                dependency changes.
370
371     dependall  Does a ``make depend'' immediately followed by a ``make all''.
372                This combined target recurses as an atomic unit, so that the
373                ``make depend'' phase can participate in make -j parallelism.
374
375     includes   Build and install system header files.  Typically needed be-
376                fore any system libraries or programs can be built.
377
378     install    Install programs, libraries, and documentation into DESTDIR.
379
380     lint       Run lint(1) against the C source code, where appropriate, and
381                generate system-installed lint libraries.
382
383     obj        Create object directories to be used for built files, instead
384                of building directly in the source tree.
385
386     tags       Create ctags(1) searchable function lists usable by the ex(1)
387                and vi(1) text editors.
388
389   "make" targets for the top level
390     Additional make(1) targets are usable specifically from the top source
391     level to facilitate building the entire NetBSD source tree.
392
393     build      Build the entire NetBSD system.  This orders portions of the
394                source tree such that prerequisites will be built in the prop-
395                er order.
396
397     release    Do a ``make build'', then package the system into a standard
398                release layout as described by release(7).  This requires that
399                RELEASEDIR be set (see above).
400
401     regression-tests
402                Can only be run after building the regression tests in the di-
403                rectory ``regress''.  Runs the compiled regression tests on
404                the local host.
405
406   The "build.sh" script
407     This script file is a Bourne shell script designed to build the entire
408     NetBSD system on any host with a Bourne shell in /bin/sh, including many
409     that are not POSIX compliant.  Note that if a host system's /bin/sh is
410     unusually old and broken, the Korn Shell (/bin/ksh), if available, may be
411     a usable alternative.
412
413     All cross-compile builds, and most native builds, of the entire system
414     should make use of build.sh rather than just running ``make''.  This way,
415     the make(1) program will be bootstrapped properly, in case the host sys-
416     tem has an older or incompatible ``make'' program.
417
418     When compiling the entire system via build.sh, many make(1) variables are
419     set for you in order to help encapsulate the build process.  In the list
420     of options below, variables that are automatically set by build.sh are
421     noted where applicable.
422
423     The following are available command line options that may be supplied to
424     build.sh:
425
426     -a arch   Set the value of MACHINE_ARCH to arch.
427
428     -b        Bootstrap ``make'' and create a nbmake-MACHINE script (see be-
429               low).
430
431     -d        Build a full distribution.  This differs from a normal build in
432               that etc files will also be installed.  Note this does not
433               build a ``release''; no release sets are placed in ${RE-
434               LEASEDIR}.
435
436     -j njob   Set the value of NBUILDJOBS to njob.  This provides similar
437               functionality to the familiar ``make -j'', but preserves the
438               ordering of the top level ``make build''.
439
440     -m mach   Set the value of MACHINE to mach.  This will also override any
441               value of MACHINE_ARCH in the process environment with a value
442               deduced from mach, unless -a is specified.  All cross builds
443               require -m, but if unset on a NetBSD host, the host's value of
444               MACHINE will be detected and used automatically.
445
446     -n        Show the commands that would be executed by build.sh, but do
447               not make any changes.  This is similar in concept to ``make
448               -n''.
449
450     -o        Set the value of MKOBJDIRS to ``no''.
451
452     -r        Remove the contents of DESTDIR and TOOLDIR before building
453               (provides a clean starting point).  This will skip deleting
454               DESTDIR if building on a native system to the root directory.
455
456     -t        Build and install the host tools from src/tools only.  This op-
457               tion implies -b.
458
459     -u        Set the UPDATE variable.
460
461     -w wrapper
462               Create the nbmake wrapper script (see below) in a custom loca-
463               tion, specified by wrapper.  This allows, for instance, to
464               place the wrapper in PATH automatically.  Note that wrapper is
465               the full name of the file, not just a directory name.
466
467     -D dest   Set the value of DESTDIR to dest.
468
469     -O obj    Create an appropriate transform macro for MAKEOBJDIR that will
470               place the built object files under obj.  For instance, a set-
471               ting of /usr/obj will place build-time files files under
472               /usr/obj/bin, /usr/obj/lib, and so forth.
473
474     -R rel    Set the value of RELEASEDIR to rel.  Setting this option will
475               cause build.sh to run ``make release'' instead of ``make
476               build''.
477
478     -T tools  Set the value of TOOLDIR to tools.  If set, the bootstrap
479               ``make'' will only be rebuilt as needed (when the source files
480               for make(1) change).
481
482     -U        Set the UNPRIVED variable.
483
484   The "nbmake-MACHINE" wrapper script
485     If using the build.sh script to build NetBSD, a nbmake-MACHINE script
486     will be created in TOOLDIR/bin upon the first build to assist in building
487     subtrees on a cross-compile host.
488
489     nbmake-MACHINE can be invoked in lieu of make(1), and will instead call
490     the up-to-date version of ``nbmake'' installed into TOOLDIR/bin with sev-
491     eral key variables pre-set, including MACHINE, MACHINE_ARCH, and TOOLDIR.
492     This script can be symlinked into a directory listed in PATH, or called
493     with an absolute path.
494
495SEE ALSO
496     make(1), hier(7), release(7)
497
498HISTORY
499     The USE_NEW_TOOLCHAIN based build scheme was introduced in the ``NetBSD-
500     current'' development sources between NetBSD 1.5 and NetBSD 1.6.
501
502BUGS
503     Many platforms are not yet using the USE_NEW_TOOLCHAIN system.
504
505NetBSD                           March 5, 2002                               8
506