BUILDING revision 1.7
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  (For building from out-of-date systems or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   "make" variables
92     Several variables control the behavior of NetBSD builds.  Unless other-
93     wise specified, these variables may be set in either the process environ-
94     ment or the make(1) configuration file specified by MAKECONF.
95
96     DESTDIR     Directory to contain the built NetBSD system.  If set, spe-
97                 cial options are passed to the compilation tools to prevent
98                 their default use of the host system's /usr/include,
99                 /usr/lib, and so forth.  This pathname should not end with a
100                 slash (/) character (for installation into the system's root
101                 directory, set DESTDIR to an empty string).  The directory
102                 must reside on a file system which supports long file names
103                 and hard links.
104
105                 Default: Empty string if USETOOLS is ``yes''; unset other-
106                 wise.
107
108     MAKECONF    The name of the make(1) configuration file.  Only settable in
109                 the process environment.
110
111                 Default: ``/etc/mk.conf''
112
113     MKCATPAGES  Can be set to ``yes'' or ``no''.  Indicates whether prefor-
114                 matted plaintext manual pages will be created during a build.
115
116                 Default: ``yes''
117
118     MKCRYPTO    Can be set to ``yes'' or ``no''.  Indicates whether crypto-
119                 graphic code will be included in a build; provided for the
120                 benefit of countries that do not allow strong cryptography.
121                 Will not affect use of the standard low-security password en-
122                 cryption system, crypt(3).
123
124                 Default: ``yes''
125
126     MKDOC       Can be set to ``yes'' or ``no''.  Indicates whether system
127                 documentation destined for /usr/share/doc will be installed
128                 during a build.
129
130                 Default: ``yes''
131
132     MKHOSTOBJ   Can be set to ``yes'' or ``no''.  If set to ``yes'', then for
133                 programs intended to be run on the compile host, the name,
134                 release, and architecture of the host operating system will
135                 be suffixed to the name of the object directory created by
136                 ``make obj''.  (This allows multiple host systems to compile
137                 NetBSD for a single target.)  If set to ``no'', then programs
138                 built to be run on the compile host will use the same object
139                 directory names as programs built to be run on the target.
140
141                 Default: ``no''
142
143     MKINFO      Can be set to ``yes'' or ``no''.  Indicates whether GNU Info
144                 files, used for the documentation for most of the compilation
145                 tools, will be created and installed during a build.
146
147                 Default: ``yes''
148
149     MKLINT      Can be set to ``yes'' or ``no''.  Indicates whether lint(1)
150                 will be run against portions of the NetBSD source code during
151                 the build, and whether lint libraries will be installed into
152                 /usr/libdata/lint.
153
154                 Default: ``yes''
155
156     MKMAN       Can be set to ``yes'' or ``no''.  Indicates whether manual
157                 pages will be installed during a build.
158
159                 Default: ``yes''
160
161     MKNLS       Can be set to ``yes'' or ``no''.  Indicates whether Native
162                 Language System locale zone files will be compiled and in-
163                 stalled during a build.
164
165                 Default: ``yes''
166
167     MKOBJ       Can be set to ``yes'' or ``no''.  Indicates whether object
168                 directories will be created when running ``make obj''.  If
169                 set to ``no'', then all built files will be located inside
170                 the regular source tree.
171
172                 Default: ``yes''
173
174     MKPIC       Can be set to ``yes'' or ``no''.  Indicates whether shared
175                 objects and libraries will be created and installed during a
176                 build.  If set to ``no'', the entire built system will be
177                 statically linked.
178
179                 Default: Platform dependent.  As of this writing, all plat-
180                 forms except sh3 default to ``yes''.
181
182     MKPICINSTALL
183                 Can be set to ``yes'' or ``no''.  Indicates whether the ar(1)
184                 format libraries (lib*_pic.a), used to generate shared li-
185                 braries, are installed during a build.
186
187                 Default: ``yes''
188
189     MKPROFILE   Can be set to ``yes'' or ``no''.  Indicates whether profiled
190                 libraries (lib*_p.a) will be built and installed during a
191                 build.
192
193                 Default: ``yes''; however, some platforms turn off MKPROFILE
194                 by default at times due to toolchain problems with profiled
195                 code.
196
197     MKSHARE     Can be set to ``yes'' or ``no''.  Indicates whether files
198                 destined to reside in /usr/share will be built and installed
199                 during a build.  If set to ``no'', then all of MKCATPAGES,
200                 MKDOC, MKINFO, MKMAN, and MKNLS will be set to ``no'' uncon-
201                 ditionally.
202
203                 Default: ``yes''
204
205     TOOLDIR     Directory to hold the host tools, once built.  This directory
206                 should be unique to a given host system and NetBSD source
207                 tree.  (However, multiple targets may share the same TOOLDIR;
208                 the target-dependent files have unique names.)  If unset, a
209                 default based on the uname(1) information of the host plat-
210                 form will be created in the .OBJDIR of src/tools.
211
212                 Default: Unset.
213
214     UNPRIVED    If set, then an unprivileged install will occur.  The user,
215                 group, permissions, and file flags, will not be set on the
216                 installed item; instead the information will be appended to a
217                 file called METALOG in the .OBJDIR of src.  The contents of
218                 METALOG is used during the generation of the distribution tar
219                 files to ensure that the appropriate file ownership is
220                 stored.
221
222                 Default: Unset.
223
224     UPDATE      If set, then all install operations intended to write to
225                 DESTDIR will compare file timestamps before installing, and
226                 skip the install phase if the destination files are up-to-
227                 date.  This also has implications on full builds (see next
228                 subsection).
229
230                 Default: Unset.
231
232     USETOOLS    Indicates whether the tools specified by TOOLDIR should be
233                 used as part of a build in progress.  Must be set to ``yes''
234                 if cross-compiling.
235
236                 yes    Use the tools from TOOLDIR.
237
238                 no     Do not use the tools from TOOLDIR, but refuse to build
239                        native compilation tool components that are version-
240                        specific for that tool.
241
242                 never  Do not use the tools from TOOLDIR, even when building
243                        native tool components.  This is similar to the tradi-
244                        tional NetBSD build method, but does not verify that
245                        the compilation tools in use are up-to-date enough in
246                        order to build the tree successfully.  This may cause
247                        build or runtime problems when building the whole
248                        NetBSD source tree.
249
250                 Default: ``yes'' if building all or part of a whole NetBSD
251                 source tree (detected automatically); ``no'' otherwise (to
252                 preserve traditional semantics of the <bsd.*.mk> make(1) in-
253                 clude files).
254
255   "make" variables for full builds
256     These variables only affect the top level ``Makefile'' and do not affect
257     manually building subtrees of the NetBSD source code.
258
259     MKOBJDIRS      Can be set to ``yes'' or ``no''.  Indicates whether object
260                    directories will be created automatically (via a ``make
261                    obj'' pass) at the start of a build.
262
263                    Default: ``yes''
264
265     NBUILDJOBS     If set, specifies the number of parallel make(1) processes
266                    that should be run simultaneously.  This can speed up
267                    builds on SMP machines, or machines with much more CPU
268                    power than I/O availability.  This should be used instead
269                    of the make(1) option -j, in order to ensure proper order-
270                    ing of build components.
271
272                    Default: Unset.
273
274     NOCLEANDIR     If set, avoids the ``make cleandir'' phase of a full
275                    build.  This has the effect of allowing only changed files
276                    in a source tree to be recompiled.  This can speed up
277                    builds when updating only a few files in the tree.
278
279                    Default: Unset.
280
281     NODISTRIBDIRS  If set, avoids the ``make distrib-dirs'' phase of a full
282                    build.  This skips running mtree(8) on DESTDIR, useful on
283                    systems where building as an unprivileged user, or where
284                    it is known that the system-wide mtree files have not
285                    changed.
286
287                    Default: Unset.
288
289     NOINCLUDES     If set, avoids the ``make includes'' phase of a full
290                    build.  This has the effect of preventing make(1) from
291                    thinking that some programs are out-of-date simply because
292                    the system include files have changed.  However, this op-
293                    tion should not be used when updating the entire NetBSD
294                    source tree arbitrarily; it is suggested to use UPDATE in
295                    that case.
296
297                    Default: Unset.
298
299     RELEASEDIR     If set, specifies the directory to which a release(7) lay-
300                    out will be written at the end of a ``make release''.
301
302                    Default: Unset.
303
304     UPDATE         If set, then in addition to the effects described for UP-
305                    DATE above, this implies the effects of NOCLEANDIR.
306
307BUILDING
308   "make" command line options
309     This is only a summary of options available to make(1); only the options
310     used most frequently with NetBSD builds are listed here.
311
312     -m dir     Specify the default directory for searching for system Make-
313                file segments, mainly the <bsd.*.mk> files.  When building any
314                full NetBSD source tree, this should be set to the
315                ``share/mk'' directory in the source tree.  (This is set auto-
316                matically when building from the top level.)
317
318     -n         Display the commands that would have been executed, but do not
319                actually execute them.  This will still cause recursion to
320                take place.
321
322     -v var     Print make(1)'s idea of the value of var.  Does not build any
323                targets.
324
325     var=value  Set the variable var to value, overriding any setting speci-
326                fied by the process environment, the MAKECONF configuration
327                file, or the system Makefile segments.
328
329   "make" targets
330     These default targets may be built by running make(1) in any subtree of
331     the NetBSD source code.  It is recommended that none of these be used
332     from the top level Makefile; as a specific exception, ``make obj'' and
333     ``make cleandir'' are useful in that context.
334
335     all        Build programs, libraries, and preformatted documentation.
336
337     clean      Remove program and library object code files.
338
339     cleandir   Same as clean, but also remove preformatted documentation, de-
340                pendency files generated by ``make depend'', and any other
341                files known to be created at build time.  ``make distclean''
342                may be used as a synonym, for familiarity with a similar well-
343                known convention.
344
345     depend     Create dependency files (.depend) containing more detailed in-
346                formation about the dependencies of source code on header
347                files.  Allows programs to be recompiled automatically when a
348                dependency changes.
349
350     dependall  Does a ``make depend'' immediately followed by a ``make all''.
351                This combined target recurses as an atomic unit, so that the
352                ``make depend'' phase can participate in make -j parallelism.
353
354     includes   Build and install system header files.  Typically needed be-
355                fore any system libraries or programs can be built.
356
357     install    Install programs, libraries, and documentation into DESTDIR.
358
359     lint       Run lint(1) against the C source code, where appropriate, and
360                generate system-installed lint libraries.
361
362     obj        Create object directories to be used for built files, instead
363                of building directly in the source tree.
364
365     tags       Create ctags(1) searchable function lists usable by the ex(1)
366                and vi(1) text editors.
367
368   "make" targets for the top level
369     Additional make(1) targets are usable specifically from the top source
370     level to facilitate building the entire NetBSD source tree.
371
372     build      Build the entire NetBSD system.  This orders portions of the
373                source tree such that prerequisites will be built in the prop-
374                er order.
375
376     release    Do a ``make build'', then package the system into a standard
377                release layout as described by release(7).  This requires that
378                RELEASEDIR be set (see above).
379
380     regression-tests
381                Can only be run after building the regression tests in the di-
382                rectory ``regress''.  Runs the compiled regression tests on
383                the local host.
384
385   The "build.sh" script
386     This script file is a Bourne shell script designed to build the entire
387     NetBSD system on any host with a Bourne shell in /bin/sh, including many
388     that are not POSIX compliant.  Note that if a host system's /bin/sh is
389     unusually old and broken, the Korn Shell (/bin/ksh), if available, may be
390     a usable alternative.
391
392     All cross-compile builds, and most native builds, of the entire system
393     should make use of build.sh rather than just running ``make''.  This way,
394     the make(1) program will be bootstrapped properly, in case the host sys-
395     tem has an older or incompatible ``make'' program.
396
397     When compiling the entire system via build.sh, many make(1) variables are
398     set for you in order to help encapsulate the build process.  In the list
399     of options below, variables that are automatically set by build.sh are
400     noted where applicable.
401
402     The following are available command line options that may be supplied to
403     build.sh:
404
405     -a arch   Set the value of MACHINE_ARCH to arch.
406
407     -b        Bootstrap ``make'' and create a nbmake-MACHINE script (see be-
408               low).
409
410     -d        Build a full distribution.  This differs from a normal build in
411               that etc files will also be installed.  Note this does not
412               build a ``release''; no release sets are placed in ${RE-
413               LEASEDIR}.
414
415     -j njob   Set the value of NBUILDJOBS to njob.  This provides similar
416               functionality to the familiar ``make -j'', but preserves the
417               ordering of the top level ``make build''.
418
419     -m mach   Set the value of MACHINE to mach.  This will also override any
420               value of MACHINE_ARCH in the process environment with a value
421               deduced from mach, unless -a is specified.  All cross builds
422               require -m, but if unset on a NetBSD host, the host's value of
423               MACHINE will be detected and used automatically.
424
425     -n        Show the commands that would be executed by build.sh, but do
426               not make any changes.  This is similar in concept to ``make
427               -n''.
428
429     -o        Set the value of MKOBJDIRS to ``no''.
430
431     -r        Remove the contents of DESTDIR and TOOLDIR before building
432               (provides a clean starting point).  This will skip deleting
433               DESTDIR if building on a native system to the root directory.
434
435     -t        Build and install the host tools from src/tools only.  This op-
436               tion implies -b.
437
438     -u        Set the UPDATE variable.
439
440     -w wrapper
441               Create the nbmake wrapper script (see below) in a custom loca-
442               tion, specified by wrapper.  This allows, for instance, to
443               place the wrapper in PATH automatically.  Note that wrapper is
444               the full name of the file, not just a directory name.
445
446     -D dest   Set the value of DESTDIR to dest.
447
448     -O obj    Create an appropriate transform macro for MAKEOBJDIR that will
449               place the built object files under obj.  For instance, a set-
450               ting of /usr/obj will place build-time files files under
451               /usr/obj/bin, /usr/obj/lib, and so forth.
452
453     -R rel    Set the value of RELEASEDIR to rel.  Setting this option will
454               cause build.sh to run ``make release'' instead of ``make
455               build''.
456
457     -T tools  Set the value of TOOLDIR to tools.  If set, the bootstrap
458               ``make'' will only be rebuilt as needed (when the source files
459               for make(1) change).
460
461     -U        Set the UNPRIVED variable.
462
463   The "nbmake-MACHINE" wrapper script
464     If using the build.sh script to build NetBSD, a nbmake-MACHINE script
465     will be created in TOOLDIR/bin upon the first build to assist in building
466     subtrees on a cross-compile host.
467
468     nbmake-MACHINE can be invoked in lieu of make(1), and will instead call
469     the up-to-date version of ``nbmake'' installed into TOOLDIR/bin with sev-
470     eral key variables pre-set, including MACHINE, MACHINE_ARCH, and TOOLDIR.
471     This script can be symlinked into a directory listed in PATH, or called
472     with an absolute path.
473
474SEE ALSO
475     make(1), hier(7), release(7)
476
477HISTORY
478     The USE_NEW_TOOLCHAIN based build scheme was introduced in the ``NetBSD-
479     current'' development sources between NetBSD 1.5 and NetBSD 1.6.
480
481BUGS
482     Many platforms are not yet using the USE_NEW_TOOLCHAIN system.
483
484NetBSD                           March 4, 2002                               8
485