1 <!DOCTYPE Article PUBLIC "-//OASIS//DTD DocBook V3.1//EN">
7 <Title>Building the Glasgow Functional Programming Tools Suite</Title>
8 <Author><OtherName>The GHC Team</OtherName></Author>
9 <Address><Email>glasgow-haskell-{users,bugs}@haskell.org</Email></Address>
10 <PubDate>January 2000</PubDate>
15 This guide is intended for people who want to build or modify
16 programs from the Glasgow <Literal>fptools</Literal> suite (as distinct from those
17 who merely want to <Emphasis>run</Emphasis> them). Installation instructions are now provided in the user guide.
21 The bulk of this guide applies to building on Unix systems; see <XRef LinkEnd="winbuild"> for Windows notes.
29 <Sect1 id="sec-getting">
30 <Title>Getting the Glasgow <Literal>fptools</Literal> suite
34 Building the Glasgow tools <Emphasis>can</Emphasis> be complicated, mostly because
35 there are so many permutations of what/why/how, e.g., ``Build Happy
36 with HBC, everything else with GHC, leave out profiling, and test it
37 all on the `real' NoFib programs.'' Yeeps!
41 Happily, such complications don't apply to most people. A few common
42 ``strategies'' serve most purposes. Pick one and proceed
50 <Term><IndexTerm><Primary>Binary distribution</Primary></IndexTerm>Binary distribution.</Term>
53 If your only purpose is to install some of the <Literal>fptools</Literal> suite then the easiest thing to do is to get a binary distribution. In the
54 binary distribution everything is pre-compiled for your particular
55 machine architecture and operating system, so all you should have to
56 do is install the binaries and libraries in suitable places. The user guide
57 describes how to do this.
61 A binary distribution may not work for you for two reasons. First, we
62 may not have built the suite for the particular architecture/OS
63 platform you want. That may be due to lack of time and energy (in
64 which case you can get a source distribution and build from it; see
65 below). Alternatively, it may be because we haven't yet ported the
66 suite to your architecture, in which case you are considerably worse
71 The second reason a binary distribution may not be what you want is
72 if you want to read or modify the souce code.
74 </ListItem></VarListEntry>
76 <Term><IndexTerm><Primary>Source distribution</Primary></IndexTerm>Source distribution.</Term>
80 platform, but (a) you like the warm fuzzy feeling of compiling things
81 yourself; (b) you want to build something ``extra''—e.g., a set of
82 libraries with strictness-analysis turned off; or (c) you want to hack
87 A source distribution contains complete sources for one or more
88 projects in the <Literal>fptools</Literal> suite. Not only that, but the more awkward
89 machine-independent steps are done for you. For example, if you don't
90 have <Command>flex</Command><IndexTerm><Primary>flex</Primary></IndexTerm> you'll find it convenient that the source
91 distribution contains the result of running <Command>flex</Command> on the lexical
92 analyser specification. If you don't want to alter the lexical
93 analyser then this saves you having to find and install <Command>flex</Command>. You
94 will still need a working version of GHC on your machine in order to
95 compile (most of) the sources, however.
99 We make source distributions more frequently than binary
100 distributions; a release that comes with pre-compiled binaries
101 is considered a major release, i.e., a release that we have some
102 confidence will work well by having tested it (more) thoroughly.
106 Source-only distributions are either bugfix releases or snapshots of
107 current state of development. The release has undergone some testing.
108 Source releases of GHC 4.xx can be compiled up using GHC 2.10 or
111 </ListItem></VarListEntry>
113 <Term>Build GHC from intermediate C <Filename>.hc</Filename> files<IndexTerm><Primary>hc files</Primary></IndexTerm>:</Term>
117 need a working GHC to use a source distribution. What if you don't
118 have a working GHC? Then you have no choice but to ``bootstrap'' up
119 from the intermediate C (<Filename>.hc</Filename>) files that we provide. Building GHC
120 on an unsupported platform falls into this category. Please see
121 <Xref LinkEnd="sec-booting-from-C">.
125 Once you have built GHC, you can build the other Glasgow tools with
130 In theory, you can (could?) build GHC with another Haskell compiler
131 (e.g., HBC). We haven't tried to do this for ages and it almost
132 certainly doesn't work any more (for tedious reasons).
134 </ListItem></VarListEntry>
136 <Term>The CVS repository.</Term>
139 We make source distributions slightly more often than binary
140 distributions; but still infrequently. If you want more up-to-the
141 minute (but less tested) source code then you need to get access to
146 All the <Literal>fptools</Literal> source code is held in a CVS repository. CVS is a
147 pretty good source-code control system, and best of all it works over
152 The repository holds source code only. It holds no mechanically
153 generated files at all. So if you check out a source tree from CVS
154 you will need to install every utility so that you can build all the
155 derived files from scratch.
159 More information about our CVS repository is available in the <ULink
160 URL="http://www.haskell.org/ghc/cvs-cheat-sheet.html" >FPTools CVS
161 Cheat Sheet</ULink >.
163 </ListItem></VarListEntry>
168 If you are going to do any building from sources (either from a source
169 distribution or the CVS repository) then you need to read all of this
176 <Title>Things to check before you start typing</Title>
179 Here's a list of things to check before you get started.
185 <IndexTerm><Primary>Disk space needed</Primary></IndexTerm>Disk space needed: About 30MB (five hamburgers' worth) of disk space
186 for the most basic binary distribution of GHC; more for some
187 platforms, e.g., Alphas. An extra ``bundle'' (e.g., concurrent
188 Haskell libraries) might take you to 8–10 hamburgers.
190 You'll need over 100MB (say, 20 hamburgers' worth) if you need to
191 build the basic stuff from scratch.
194 All of the above are <Emphasis>estimates</Emphasis> of disk-space needs. (I don't yet
195 know the disk requirements for the non-GHC tools).
202 Use an appropriate machine, compilers, and things.
204 SPARC boxes, and PCs running Linux, FreeBSD, NetBSD, or Solaris are
205 all fully supported. Win32 and HP boxes are in pretty good shape.
206 DEC Alphas running OSF/1, Linux or some BSD variant, MIPS and AIX
207 boxes will need some minimal porting effort before they work (as of
208 4.06). <Xref LinkEnd="sec-port-info"> gives the full run-down on
209 ports or lack thereof.
216 Be sure that the ``pre-supposed'' utilities are installed.
217 <Xref LinkEnd="sec-pre-supposed"> elaborates.
224 If you have any problem when building or installing the Glasgow
225 tools, please check the ``known pitfalls'' (<Xref
226 LinkEnd="sec-build-pitfalls">). Also check the FAQ for the version
227 you're building, which should be available from the relevant download
228 page on the <ULink URL="http://www.haskell.org/ghc/" >GHC web
231 <IndexTerm><Primary>known bugs</Primary></IndexTerm>
232 <IndexTerm><Primary>bugs, known</Primary></IndexTerm>
234 If you feel there is still some shortcoming in our procedure or
235 instructions, please report it.
237 For GHC, please see the bug-reporting section of the GHC Users' Guide
238 (separate document), to maximise the usefulness of your report.
239 <IndexTerm><Primary>bugs, reporting</Primary></IndexTerm>
241 If in doubt, please send a message to
242 <Email>glasgow-haskell-bugs@haskell.org</Email>.
243 <IndexTerm><Primary>bugs, mailing list</Primary></IndexTerm>
253 <Sect1 id="sec-port-info">
254 <Title>What machines the Glasgow tools run on
258 <IndexTerm><Primary>ports, GHC</Primary></IndexTerm>
259 <IndexTerm><Primary>GHC ports</Primary></IndexTerm>
260 <IndexTerm><Primary>supported platforms</Primary></IndexTerm>
261 <IndexTerm><Primary>platforms, supported</Primary></IndexTerm>
262 The main question is whether or not the Haskell compiler (GHC) runs on
267 A ``platform'' is a architecture/manufacturer/operating-system
268 combination, such as <Literal>sparc-sun-solaris2</Literal>. Other common ones are
269 <Literal>alpha-dec-osf2</Literal>, <Literal>hppa1.1-hp-hpux9</Literal>, <Literal>i386-unknown-linux</Literal>,
270 <Literal>i386-unknown-solaris2</Literal>, <Literal>i386-unknown-freebsd</Literal>,
271 <Literal>i386-unknown-cygwin32</Literal>, <Literal>m68k-sun-sunos4</Literal>, <Literal>mips-sgi-irix5</Literal>,
272 <Literal>sparc-sun-sunos4</Literal>, <Literal>sparc-sun-solaris2</Literal>, <Literal>powerpc-ibm-aix</Literal>.
276 Bear in mind that certain ``bundles'', e.g. parallel Haskell, may not
277 work on all machines for which basic Haskell compiling is supported.
281 Some libraries may only work on a limited number of platforms; for
282 example, a sockets library is of no use unless the operating system
283 supports the underlying BSDisms.
287 <Title>What platforms the Haskell compiler (GHC) runs on</Title>
290 <IndexTerm><Primary>fully-supported platforms</Primary></IndexTerm>
291 <IndexTerm><Primary>native-code generator</Primary></IndexTerm>
292 <IndexTerm><Primary>registerised ports</Primary></IndexTerm>
293 <IndexTerm><Primary>unregisterised ports</Primary></IndexTerm>
294 The GHC hierarchy of Porting Goodness: (a) Best is a native-code
295 generator; (b) next best is a ``registerised''
296 port; (c) the bare minimum is an ``unregisterised'' port.
297 (``Unregisterised'' is so terrible that we won't say more about it).
301 The native code generator is currently non-functional (as of GHC
302 version 4.06), but we're actively working on getting it going again.
306 We use Sparcs running Solaris 2.7 and x86 boxes running FreeBSD and
307 Linux, so those are the best supported platforms, unsurprisingly.
311 Here's everything that's known about GHC ports. We identify platforms
312 by their ``canonical'' CPU/Manufacturer/OS triple.
319 <Term>alpha-dec-{osf,linux,freebsd,openbsd,netbsd}:</Term>
320 <IndexTerm><Primary>alpha-dec-osf</Primary></IndexTerm>
321 <IndexTerm><Primary>alpha-dec-linux</Primary></IndexTerm>
322 <IndexTerm><Primary>alpha-dec-freebsd</Primary></IndexTerm>
323 <IndexTerm><Primary>alpha-dec-openbsd</Primary></IndexTerm>
324 <IndexTerm><Primary>alpha-dec-netbsd</Primary></IndexTerm>
328 Currently non-working. The last working version (osf[1-3]) is GHC
329 3.02. A small amount of porting effort will be required to get Alpha
330 support into GHC 4.xx, but we don't have easy access to machines right
331 now, and there hasn't been a massive demand for support, so Alphas
332 remain unsupported for the time being. Please get in touch if you
333 either need Alpha support and/or can provide access to boxes.
336 </ListItem></VarListEntry>
338 <Term>sparc-sun-sunos4:</Term>
339 <IndexTerm><Primary>sparc-sun-sunos4</Primary></IndexTerm>
343 Probably works with minor tweaks, hasn't been tested for a while.
346 </ListItem></VarListEntry>
348 <Term>sparc-sun-solaris2:</Term>
349 <IndexTerm><Primary>sparc-sun-solaris2</Primary></IndexTerm>
353 Fully supported, including native-code generator.
356 </ListItem></VarListEntry>
358 <Term>hppa1.1-hp-hpux (HP-PA boxes running HPUX 9.x)</Term>
359 <IndexTerm><Primary>hppa1.1-hp-hpux</Primary></IndexTerm>
363 Works registerised. No native-code generator.
366 </ListItem></VarListEntry>
368 <Term>i386-unknown-linux (PCs running Linux—ELF binary format):</Term>
369 <IndexTerm><Primary>i386-*-linux</Primary></IndexTerm>
373 GHC works registerised. You <Emphasis>must</Emphasis> have GCC 2.7.x
374 or later. NOTE about <literal>glibc</literal> versions: GHC binaries
375 built on a system running <literal>glibc 2.0</literal> won't work on a
376 system running <literal>glibc 2.1</literal>, and vice version. In
377 general, don't expect compatibility between <literal>glibc</literal>
378 versions, even if the shared library version hasn't changed.
381 </ListItem></VarListEntry>
383 <Term>i386-unknown-{freebsd,netbsd,openbsd) (PCs running FreeBSD 2.2
384 or higher, NetBSD, and possibly OpenBSD):</Term>
385 <IndexTerm><Primary>i386-unknown-freebsd</Primary></IndexTerm>
386 <IndexTerm><Primary>i386-unknown-netbsd</Primary></IndexTerm>
387 <IndexTerm><Primary>i386-unknown-openbsd</Primary></IndexTerm>
391 GHC works registerised. These systems provide ready-built packages of
392 GHC, so if you just need binaries you're better off just installing
396 </ListItem></VarListEntry>
398 <Term>i386-unknown-cygwin32:</Term>
399 <IndexTerm><Primary>i386-unknown-cygwin32</Primary></IndexTerm>
403 Fully supported under Win9x/NT, including a native code
404 generator. Requires the <Literal>cygwin32</Literal> compatibility
405 library and a healthy collection of GNU tools (i.e., gcc, GNU ld, bash
409 </ListItem></VarListEntry>
411 <Term>mips-sgi-irix5:</Term>
412 <IndexTerm><Primary>mips-sgi-irix[5-6]</Primary></IndexTerm>
416 Port currently doesn't work, needs some minimal porting effort. As
417 usual, we don't have access to machines and there hasn't been an
418 overwhelming demand for this port, but feel free to get in touch.
420 </ListItem></VarListEntry>
423 <Term>powerpc-ibm-aix:</Term>
426 <IndexTerm><Primary>powerpc-ibm-aix</Primary></IndexTerm>
427 Port currently doesn't work, needs some minimal porting effort. As
428 usual, we don't have access to machines and there hasn't been an
429 overwhelming demand for this port, but feel free to get in touch.
431 </ListItem></VarListEntry>
437 Various other systems have had GHC ported to them in the distant past,
438 including various Motorola 68k boxes. The 68k support still remains,
439 but porting to one of these systems will certainly be a non-trivial
446 <Title>What machines the other tools run on</Title>
449 Unless you hear otherwise, the other tools work if GHC works.
457 <Sect1 id="sec-pre-supposed">
458 <Title>Installing pre-supposed utilities
460 <IndexTerm><Primary>pre-supposed utilities</Primary></IndexTerm>
461 <IndexTerm><Primary>utilities, pre-supposed</Primary></IndexTerm></Title>
464 Here are the gory details about some utility programs you may need;
465 <Command>perl</Command>, <Command>gcc</Command> and
466 <command>happy</command> are the only important
467 ones. (PVM<IndexTerm><Primary>PVM</Primary></IndexTerm> is important
468 if you're going for Parallel Haskell.) The
469 <Command>configure</Command><IndexTerm><Primary>configure</Primary></IndexTerm>
470 script will tell you if you are missing something.
478 <IndexTerm><Primary>pre-supposed: Perl</Primary></IndexTerm>
479 <IndexTerm><Primary>Perl, pre-supposed</Primary></IndexTerm>
482 <Emphasis>You have to have Perl to proceed!</Emphasis> Perl is a
483 language quite good for doing shell-scripty tasks that involve lots of
484 text processing. It is pretty easy to install.
488 Perl 5 is required. For Win32 platforms, we strongly suggest you
489 pick up a port of Perl 5 for <Literal>cygwin32</Literal>, as the
490 common Hip/ActiveWare port of Perl is Not Cool Enough for our
495 Perl should be put somewhere so that it can be invoked by the
496 <Literal>#!</Literal> script-invoking mechanism. (I believe
497 <Filename>/usr/bin/perl</Filename> is preferred; we use
498 <Filename>/usr/local/bin/perl</Filename> at Glasgow.) The full
499 pathname should may need to be less than 32 characters long on some
503 </ListItem></VarListEntry>
505 <Term>GNU C (<Command>gcc</Command>):</Term>
506 <IndexTerm><Primary>pre-supposed: GCC (GNU C compiler)</Primary></IndexTerm>
507 <IndexTerm><Primary>GCC (GNU C compiler), pre-supposed</Primary></IndexTerm>
511 We recommend using GCC version 2.95.2 on all platforms. Failing that,
512 version 2.7.2 is stable on most platforms. Earlier versions of GCC
513 can be assumed not to work, and versions in between 2.7.2 and 2.95.2
514 (including <command>egcs</command>) have varying degrees of stability
515 depending on the platform.
519 If your GCC dies with ``internal error'' on some GHC source file,
520 please let us know, so we can report it and get things improved.
521 (Exception: on iX86 boxes—you may need to fiddle with GHC's
522 <Option>-monly-N-regs</Option> option; see the User's Guide)
524 </ListItem></VarListEntry>
528 <indexterm><primary>Happy</primary></indexterm>
530 <para>Happy is a parser generator tool for Haskell, and is used to
531 generate GHC's parsers. Happy is written in Haskell, and is a project
532 in the CVS repository (<literal>fptools/happy</literal>). It can be
533 built from source, but bear in mind that you'll need GHC installed in
534 order to build it. To avoid the chicken/egg problem, install a binary
535 distribtion of either Happy or GHC to get started. Happy
536 distributions are available from <ulink
537 url="http://www.haskell.org/happy/">Happy's Web Page</ulink>.
543 <Term>Autoconf:</Term>
544 <IndexTerm><Primary>pre-supposed: Autoconf</Primary></IndexTerm>
545 <IndexTerm><Primary>Autoconf, pre-supposed</Primary></IndexTerm>
548 GNU Autoconf is needed if you intend to build from the CVS sources, it
549 is <Emphasis>not</Emphasis> needed if you just intend to build a
550 standard source distribution.
554 Autoconf builds the <Command>configure</Command> script from
555 <Filename>configure.in</Filename> and <Filename>aclocal.m4</Filename>.
556 If you modify either of these files, you'll need Autoconf to rebuild
557 <Filename>configure</Filename>.
560 </ListItem></VarListEntry>
562 <Term><Command>sed</Command></Term>
563 <IndexTerm><Primary>pre-supposed: sed</Primary></IndexTerm>
564 <IndexTerm><Primary>sed, pre-supposed</Primary></IndexTerm>
567 You need a working <Command>sed</Command> if you are going to build
568 from sources. The build-configuration stuff needs it. GNU sed
569 version 2.0.4 is no good! It has a bug in it that is tickled by the
570 build-configuration. 2.0.5 is OK. Others are probably OK too
571 (assuming we don't create too elaborate configure scripts.)
573 </ListItem></VarListEntry>
578 One <Literal>fptools</Literal> project is worth a quick note at this
579 point, because it is useful for all the others:
580 <Literal>glafp-utils</Literal> contains several utilities which aren't
581 particularly Glasgow-ish, but Occasionally Indispensable. Like
582 <Command>lndir</Command> for creating symbolic link trees.
585 <Sect2 id="pre-supposed-gph-tools">
586 <Title>Tools for building parallel GHC (GPH)
593 <Term>PVM version 3:</Term>
594 <IndexTerm><Primary>pre-supposed: PVM3 (Parallel Virtual Machine)</Primary></IndexTerm>
595 <IndexTerm><Primary>PVM3 (Parallel Virtual Machine), pre-supposed</Primary></IndexTerm>
599 PVM is the Parallel Virtual Machine on which Parallel Haskell programs
600 run. (You only need this if you plan to run Parallel Haskell.
601 Concurent Haskell, which runs concurrent threads on a uniprocessor
602 doesn't need it.) Underneath PVM, you can have (for example) a
603 network of workstations (slow) or a multiprocessor box (faster).
607 The current version of PVM is 3.3.11; we use 3.3.7. It is readily
608 available on the net; I think I got it from
609 <Literal>research.att.com</Literal>, in <Filename>netlib</Filename>.
613 A PVM installation is slightly quirky, but easy to do. Just follow
614 the <Filename>Readme</Filename> instructions.
616 </ListItem></VarListEntry>
618 <Term><Command>bash</Command>:</Term>
619 <IndexTerm><Primary>bash, presupposed (Parallel Haskell only)</Primary></IndexTerm>
622 Sadly, the <Command>gr2ps</Command> script, used to convert ``parallelism profiles''
623 to PostScript, is written in Bash (GNU's Bourne Again shell).
624 This bug will be fixed (someday).
626 </ListItem></VarListEntry>
632 <Sect2 id="pre-supposed-doc-tools">
633 <Title>Tools for building the Documentation
637 The following additional tools are required if you want to format the
638 documentation that comes with the <Literal>fptools</Literal> projects:
645 <Term>DocBook:</Term>
646 <IndexTerm><Primary>pre-supposed: DocBook</Primary></IndexTerm>
647 <IndexTerm><Primary>DocBook, pre-supposed</Primary></IndexTerm>
650 All our documentation is written in SGML, using the DocBook DTD.
651 Instructions on how to install the SGML processor Jade and the DocBook DTD
652 and DSSSL stylesheets follows; if you're using a system that can handle
653 RedHat RPM packages, you might be able to use the <ULink
654 URL="http://sourceware.cygnus.com/docbook-tools/">Cygnus DocBook
655 tools</ULink>, which is the most shrink-wrapped SGML suite that we
656 could find. You need all the RPMs except for psgml (i.e. docbook, jade,
657 jadetex, sgmlcommon and stylesheets). N.B. The
658 <Emphasis>Cygnus</Emphasis> version of the tools is assumed. Others, such as
659 the SuSE version, may not work. Note that most of these RPMs are
660 architecture neutral, so are likely to be found in a
661 <Filename>noarch</Filename>
665 </ListItem></VarListEntry>
668 <IndexTerm><Primary>pre-supposed: TeX</Primary></IndexTerm>
669 <IndexTerm><Primary>TeX, pre-supposed</Primary></IndexTerm>
672 A decent TeX distribution is required if you want to produce printable
673 documentation. We recomment teTeX, which includes just about
676 </ListItem></VarListEntry>
682 <Sect2 id="pre-supposed-other-tools">
683 <Title>Other useful tools
689 <IndexTerm><Primary>pre-supposed: flex</Primary></IndexTerm>
690 <IndexTerm><Primary>flex, pre-supposed</Primary></IndexTerm>
694 This is a quite-a-bit-better-than-Lex lexer. Used to build a couple
695 of utilities in <Literal>glafp-utils</Literal>. Depending on your
696 operating system, the supplied <Command>lex</Command> may or may not
697 work; you should get the GNU version.
699 </ListItem></VarListEntry>
706 <Sect1 id="sec-building-from-source">
707 <Title>Building from source
709 <IndexTerm><Primary>Building from source</Primary></IndexTerm>
710 <IndexTerm><Primary>Source, building from</Primary></IndexTerm></Title>
713 You've been rash enough to want to build some of
714 the Glasgow Functional Programming tools (GHC, Happy,
715 nofib, etc.) from source. You've slurped the source,
716 from the CVS repository or from a source distribution, and
717 now you're sitting looking at a huge mound of bits, wondering
722 Gingerly, you type <Command>make</Command>. Wrong already!
726 This rest of this guide is intended for duffers like me, who aren't
727 really interested in Makefiles and systems configurations, but who
728 need a mental model of the interlocking pieces so that they can make
729 them work, extend them consistently when adding new software, and lay
730 hands on them gently when they don't work.
733 <Sect2 id="sec-source-tree">
734 <Title>Your source tree
738 The source code is held in your <Emphasis>source tree</Emphasis>.
739 The root directory of your source tree <Emphasis>must</Emphasis>
740 contain the following directories and files:
749 <Filename>Makefile</Filename>: the root Makefile.
755 <Filename>mk/</Filename>: the directory that contains the
756 main Makefile code, shared by all the
757 <Literal>fptools</Literal> software.
763 <Filename>configure.in</Filename>, <Filename>config.sub</Filename>, <Filename>config.guess</Filename>:
764 these files support the configuration process.
770 <Filename>install-sh</Filename>.
779 All the other directories are individual <Emphasis>projects</Emphasis> of the
780 <Literal>fptools</Literal> system—for example, the Glasgow Haskell Compiler
781 (<Literal>ghc</Literal>), the Happy parser generator (<Literal>happy</Literal>), the <Literal>nofib</Literal> benchmark
782 suite, and so on. You can have zero or more of these. Needless to
783 say, some of them are needed to build others.
787 The important thing to remember is that even if you want only one
788 project (<Literal>happy</Literal>, say), you must have a source tree whose root
789 directory contains <Filename>Makefile</Filename>, <Filename>mk/</Filename>, <Filename>configure.in</Filename>, and the
790 project(s) you want (<Filename>happy/</Filename> in this case). You cannot get by with
791 just the <Filename>happy/</Filename> directory.
798 <IndexTerm><Primary>build trees</Primary></IndexTerm>
799 <IndexTerm><Primary>link trees, for building</Primary></IndexTerm></Title>
802 While you can build a system in the source tree, we don't recommend it.
803 We often want to build multiple versions of our software
804 for different architectures, or with different options (e.g. profiling).
805 It's very desirable to share a single copy of the source code among
810 So for every source tree we have zero or more <Emphasis>build trees</Emphasis>. Each
811 build tree is initially an exact copy of the source tree, except that
812 each file is a symbolic link to the source file, rather than being a
813 copy of the source file. There are ``standard'' Unix utilities that
814 make such copies, so standard that they go by different names:
815 <Command>lndir</Command><IndexTerm><Primary>lndir</Primary></IndexTerm>, <Command>mkshadowdir</Command><IndexTerm><Primary>mkshadowdir</Primary></IndexTerm> are two (If you
816 don't have either, the source distribution includes sources for the
817 X11 <Command>lndir</Command>—check out <Filename>fptools/glafp-utils/lndir</Filename>). See <Xref LinkEnd="sec-storysofar"> for a typical invocation.
821 The build tree does not need to be anywhere near the source tree in
822 the file system. Indeed, one advantage of separating the build tree
823 from the source is that the build tree can be placed in a
824 non-backed-up partition, saving your systems support people from
825 backing up untold megabytes of easily-regenerated, and
826 rapidly-changing, gubbins. The golden rule is that (with a single
827 exception—<XRef LinkEnd="sec-build-config">)
828 <Emphasis>absolutely everything in the build tree is either a symbolic
829 link to the source tree, or else is mechanically generated</Emphasis>.
830 It should be perfectly OK for your build tree to vanish overnight; an
831 hour or two compiling and you're on the road again.
835 You need to be a bit careful, though, that any new files you create
836 (if you do any development work) are in the source tree, not a build tree!
840 Remember, that the source files in the build tree are <Emphasis>symbolic
841 links</Emphasis> to the files in the source tree. (The build tree soon
842 accumulates lots of built files like <Filename>Foo.o</Filename>, as well.) You
843 can <Emphasis>delete</Emphasis> a source file from the build tree without affecting
844 the source tree (though it's an odd thing to do). On the other hand,
845 if you <Emphasis>edit</Emphasis> a source file from the build tree, you'll edit the
846 source-tree file directly. (You can set up Emacs so that if you edit
847 a source file from the build tree, Emacs will silently create an
848 edited copy of the source file in the build tree, leaving the source
849 file unchanged; but the danger is that you think you've edited the
850 source file whereas actually all you've done is edit the build-tree
851 copy. More commonly you do want to edit the source file.)
855 Like the source tree, the top level of your build tree must be (a
856 linked copy of) the root directory of the <Literal>fptools</Literal> suite. Inside
857 Makefiles, the root of your build tree is called
858 <Constant>$(FPTOOLS_TOP)</Constant><IndexTerm><Primary>FPTOOLS_TOP</Primary></IndexTerm>. In the rest of this document path
859 names are relative to <Constant>$(FPTOOLS_TOP)</Constant> unless otherwise stated. For
860 example, the file <Filename>ghc/mk/target.mk</Filename> is actually
861 <Filename><Constant>$(FPTOOLS_TOP)</Constant>/ghc/mk/target.mk</Filename>.
866 <Sect2 id="sec-build-config">
867 <Title>Getting the build you want
871 When you build <Literal>fptools</Literal> you will be compiling code on a particular
872 <Emphasis>host platform</Emphasis>, to run on a particular <Emphasis>target platform</Emphasis>
873 (usually the same as the host platform)<IndexTerm><Primary>platform</Primary></IndexTerm>. The
874 difficulty is that there are minor differences between different
875 platforms; minor, but enough that the code needs to be a bit different
876 for each. There are some big differences too: for a different
877 architecture we need to build GHC with a different native-code
882 There are also knobs you can turn to control how the <Literal>fptools</Literal>
883 software is built. For example, you might want to build GHC optimised
884 (so that it runs fast) or unoptimised (so that you can compile it fast
885 after you've modified it. Or, you might want to compile it with
886 debugging on (so that extra consistency-checking code gets included)
891 All of this stuff is called the <Emphasis>configuration</Emphasis> of your build.
892 You set the configuration using a three-step process.
896 <Term>Step 1: get ready for configuration.</Term>
900 <Constant>$(FPTOOLS_TOP)</Constant> and issue the command <Command>autoconf</Command><IndexTerm><Primary>autoconf</Primary></IndexTerm> (with
901 no arguments). This GNU program converts <Filename><Constant>$(FPTOOLS_TOP)</Constant>/configure.in</Filename>
902 to a shell script called <Filename><Constant>$(FPTOOLS_TOP)</Constant>/configure</Filename>.
906 Some projects, including GHC, have their own configure script. If
908 <Constant>$(FPTOOLS_TOP)/<project>/configure.in</Constant>,
909 then you need to run <command>autoconf</command> in that directory too.
913 Both these steps are completely platform-independent; they just mean
914 that the human-written file (<Filename>configure.in</Filename>) can be short, although
915 the resulting shell script, <Command>configure</Command>, and <Filename>mk/config.h.in</Filename>, are
920 In case you don't have <Command>autoconf</Command> we distribute the results,
921 <Command>configure</Command>, and <Filename>mk/config.h.in</Filename>, with the source distribution. They
922 aren't kept in the repository, though.
924 </ListItem></VarListEntry>
926 <Term>Step 2: system configuration.</Term>
929 Runs the newly-created <Command>configure</Command> script, thus:
935 <Command>configure</Command>'s mission is to scurry round your
936 computer working out what architecture it has, what operating system,
937 whether it has the <Function>vfork</Function> system call, where
938 <Command>yacc</Command> is kept, whether <Command>gcc</Command> is
939 available, where various obscure <Literal>#include</Literal> files
940 are, whether it's a leap year, and what the systems manager had for
941 lunch. It communicates these snippets of information in two ways:
950 It translates <Filename>mk/config.mk.in</Filename><IndexTerm><Primary>config.mk.in</Primary></IndexTerm> to
951 <Filename>mk/config.mk</Filename><IndexTerm><Primary>config.mk</Primary></IndexTerm>, substituting for things between
952 ``<Literal>@</Literal>'' brackets. So, ``<Literal>@HaveGcc@</Literal>'' will be replaced by
953 ``<Literal>YES</Literal>'' or ``<Literal>NO</Literal>'' depending on what <Command>configure</Command> finds.
954 <Filename>mk/config.mk</Filename> is included by every Makefile (directly or indirectly),
955 so the configuration information is thereby communicated to all
963 It translates <Filename>mk/config.h.in</Filename><IndexTerm><Primary>config.h.in</Primary></IndexTerm> to
964 <Filename>mk/config.h</Filename><IndexTerm><Primary>config.h</Primary></IndexTerm>. The latter is <Literal>#include</Literal>d by various C
965 programs, which can thereby make use of configuration information.
975 <Command>configure</Command> caches the results of its run in <Filename>config.cache</Filename>. Quite
976 often you don't want that; you're running <Command>configure</Command> a second time
977 because something has changed. In that case, simply delete
978 <Filename>config.cache</Filename>.
980 </ListItem></VarListEntry>
982 <Term>Step 3: build configuration.</Term>
985 Next, you say how this build of <Literal>fptools</Literal> is to differ from the
986 standard defaults by creating a new file <Filename>mk/build.mk</Filename><IndexTerm><Primary>build.mk</Primary></IndexTerm>
987 <Emphasis>in the build tree</Emphasis>. This file is the one and only file you edit
988 in the build tree, precisely because it says how this build differs
989 from the source. (Just in case your build tree does die, you might
990 want to keep a private directory of <Filename>build.mk</Filename> files, and use a
991 symbolic link in each build tree to point to the appropriate one.) So
992 <Filename>mk/build.mk</Filename> never exists in the source tree—you create one in
993 each build tree from the template. We'll discuss what to put in it
996 </ListItem></VarListEntry>
1001 And that's it for configuration. Simple, eh?
1005 What do you put in your build-specific configuration file
1006 <Filename>mk/build.mk</Filename>? <Emphasis>For almost all purposes all you will do is put
1007 make variable definitions that override those in</Emphasis> <Filename>mk/config.mk.in</Filename>.
1008 The whole point of <Filename>mk/config.mk.in</Filename>—and its derived counterpart
1009 <Filename>mk/config.mk</Filename>—is to define the build configuration. It is heavily
1010 commented, as you will see if you look at it. So generally, what you
1011 do is look at <Filename>mk/config.mk.in</Filename>, and add definitions in <Filename>mk/build.mk</Filename>
1012 that override any of the <Filename>config.mk</Filename> definitions that you want to
1013 change. (The override occurs because the main boilerplate file,
1014 <Filename>mk/boilerplate.mk</Filename><IndexTerm><Primary>boilerplate.mk</Primary></IndexTerm>, includes <Filename>build.mk</Filename> after
1015 <Filename>config.mk</Filename>.)
1019 For example, <Filename>config.mk.in</Filename> contains the definition:
1025 ProjectsToBuild = glafp-utils ghc hslibs
1031 The accompanying comment explains that this is the list of enabled
1032 projects; that is, if (after configuring) you type <Command>gmake all</Command> in
1033 <Constant>FPTOOLS_TOP</Constant> three specified projects will be made. If you want to
1034 add <Command>green-card</Command>, you can add this line to <Filename>build.mk</Filename>:
1040 ProjectsToBuild += green-card
1052 ProjectsToBuild = glafp-utils ghc green-card
1058 (GNU <Command>make</Command> allows existing definitions to have new text appended
1059 using the ``<Literal>+=</Literal>'' operator, which is quite a convenient feature.)
1063 When reading <Filename>config.mk.in</Filename>, remember that anything between
1064 ``@...@'' signs is going to be substituted by <Command>configure</Command>
1065 later. You <Emphasis>can</Emphasis> override the resulting definition if you want,
1066 but you need to be a bit surer what you are doing. For example,
1067 there's a line that says:
1079 This defines the Make variables <Constant>YACC</Constant> to the pathname for a <Command>yacc</Command> that
1080 <Command>configure</Command> finds somewhere. If you have your own pet <Command>yacc</Command> you want
1081 to use instead, that's fine. Just add this line to <Filename>mk/build.mk</Filename>:
1093 You do not <Emphasis>have</Emphasis> to have a <Filename>mk/build.mk</Filename> file at all; if you
1094 don't, you'll get all the default settings from <Filename>mk/config.mk.in</Filename>.
1098 You can also use <Filename>build.mk</Filename> to override anything that <Command>configure</Command> got
1099 wrong. One place where this happens often is with the definition of
1100 <Constant>FPTOOLS_TOP_ABS</Constant>: this variable is supposed to be the canonical path
1101 to the top of your source tree, but if your system uses an automounter
1102 then the correct directory is hard to find automatically. If you find
1103 that <Command>configure</Command> has got it wrong, just put the correct definition in
1104 <Filename>build.mk</Filename>.
1109 <Sect2 id="sec-storysofar">
1110 <Title>The story so far</Title>
1113 Let's summarise the steps you need to carry to get yourself
1114 a fully-configured build tree from scratch.
1123 Get your source tree from somewhere (CVS repository or source
1124 distribution). Say you call the root directory <Filename>myfptools</Filename> (it
1125 does not have to be called <Filename>fptools</Filename>). Make sure that you have
1126 the essential files (see <XRef LinkEnd="sec-source-tree">).
1133 Use <Command>lndir</Command> or <Command>mkshadowdir</Command> to create a build tree.
1137 mkshadowdir . /scratch/joe-bloggs/myfptools-sun4
1140 (N.B. <Command>mkshadowdir</Command>'s first argument is taken relative to its second.) You probably want to give the build tree a name that
1141 suggests its main defining characteristic (in your mind at least),
1142 in case you later add others.
1149 Change directory to the build tree. Everything is going
1150 to happen there now.
1153 cd /scratch/joe-bloggs/myfptools-sun4
1161 Prepare for system configuration:
1167 (You can skip this step if you are starting from a source distribution,
1168 and you already have <Filename>configure</Filename> and <Filename>mk/config.h.in</Filename>.)
1175 Do system configuration:
1187 Create the file <Filename>mk/build.mk</Filename>,
1188 adding definitions for your desired configuration options.
1199 You can make subsequent changes to <Filename>mk/build.mk</Filename> as often
1200 as you like. You do not have to run any further configuration
1201 programs to make these changes take effect.
1202 In theory you should, however, say <Command>gmake clean</Command>, <Command>gmake all</Command>,
1203 because configuration option changes could affect anything—but in practice you are likely to know what's affected.
1209 <Title>Making things</Title>
1212 At this point you have made yourself a fully-configured build tree,
1213 so you are ready to start building real things.
1217 The first thing you need to know is that
1218 <Emphasis>you must use GNU <Command>make</Command>, usually called <Command>gmake</Command>, not standard Unix <Command>make</Command></Emphasis>.
1219 If you use standard Unix <Command>make</Command> you will get all sorts of error messages
1220 (but no damage) because the <Literal>fptools</Literal> <Command>Makefiles</Command> use GNU <Command>make</Command>'s facilities
1226 <Sect2 id="sec-standard-targets">
1227 <Title>Standard Targets
1229 <IndexTerm><Primary>targets, standard makefile</Primary></IndexTerm>
1230 <IndexTerm><Primary>makefile targets</Primary></IndexTerm></Title>
1233 In any directory you should be able to make the following:
1237 <Term><Literal>boot</Literal>:</Term>
1240 does the one-off preparation required to get ready for the real work.
1241 Notably, it does <Command>gmake depend</Command> in all directories that contain
1242 programs. It also builds the necessary tools for compilation to proceed.
1246 You should say <Command>gmake boot</Command> right after configuring your build tree,
1247 but note that this is a one-off, i.e., there's no need to re-do
1248 <Command>gmake boot</Command> if you should re-configure your build tree at a later
1249 stage (no harm caused if you do though).
1251 </ListItem></VarListEntry>
1253 <Term><Literal>all</Literal>:</Term>
1256 makes all the final target(s) for this Makefile.
1257 Depending on which directory you are in a ``final target'' may be an
1258 executable program, a library archive, a shell script, or a Postscript
1259 file. Typing <Command>gmake</Command> alone is generally the same as typing <Command>gmake all</Command>.
1261 </ListItem></VarListEntry>
1263 <Term><Literal>install</Literal>:</Term>
1266 installs the things built by <Literal>all</Literal>. Where does it
1267 install them? That is specified by
1268 <Filename>mk/config.mk.in</Filename>; you can override it in
1269 <Filename>mk/build.mk</Filename>, or by running
1270 <command>configure</command> with command-line arguments like
1271 <literal>--bindir=/home/simonpj/bin</literal>; see <literal>./configure
1272 --help</literal> for the full details.
1274 </ListItem></VarListEntry>
1276 <Term><Literal>uninstall</Literal>:</Term>
1279 reverses the effect of <Literal>install</Literal>.
1281 </ListItem></VarListEntry>
1284 <Term><Literal>clean</Literal>:</Term>
1287 Delete all files from the current directory that are normally
1288 created by building the program. Don't delete the files that
1289 record the configuration. Also preserve files that could be made
1290 by building, but normally aren't because the distribution comes
1292 </ListItem></VarListEntry>
1295 <term><literal>distclean</literal>:</term>
1297 <para>Delete all files from the current directory that are created by
1298 configuring or building the program. If you have unpacked the source
1299 and built the program without creating any other files, <literal>make
1300 distclean</literal> should leave only the files that were in the
1301 distribution.</para>
1306 <term><literal>mostlyclean</literal>:</term>
1308 <para>Like <literal>clean</literal>, but may refrain from deleting a
1309 few files that people normally don't want to recompile.</para>
1314 <Term><Literal>maintainer-clean</Literal>:</Term>
1317 Delete everything from the current directory that can be reconstructed
1318 with this Makefile. This typically includes everything deleted by
1319 <literal>distclean</literal>, plus more: C source files produced by
1320 Bison, tags tables, Info files, and so on.</para>
1322 <para>One exception, however: <literal>make maintainer-clean</literal>
1323 should not delete <filename>configure</filename> even if
1324 <filename>configure</filename> can be remade using a rule in the
1325 <filename>Makefile</filename>. More generally, <literal>make
1326 maintainer-clean</literal> should not delete anything that needs to
1327 exist in order to run <filename>configure</filename> and then begin to
1328 build the program.</para>
1333 <Term><Literal>check</Literal>:</Term>
1338 </ListItem></VarListEntry>
1343 All of these standard targets automatically recurse into
1344 sub-directories. Certain other standard targets do not:
1351 <Term><Literal>configure</Literal>:</Term>
1354 is only available in the root directory
1355 <Constant>$(FPTOOLS_TOP)</Constant>; it has been discussed in <XRef LinkEnd="sec-build-config">.
1357 </ListItem></VarListEntry>
1359 <Term><Literal>depend</Literal>:</Term>
1362 make a <Filename>.depend</Filename> file in each directory that needs
1363 it. This <Filename>.depend</Filename> file contains mechanically-generated dependency
1364 information; for example, suppose a directory contains a Haskell
1365 source module <Filename>Foo.lhs</Filename> which imports another module <Literal>Baz</Literal>.
1366 Then the generated <Filename>.depend</Filename> file will contain the dependency:
1378 which says that the object file <Filename>Foo.o</Filename> depends on the interface file
1379 <Filename>Baz.hi</Filename> generated by compiling module <Literal>Baz</Literal>. The <Filename>.depend</Filename> file is
1380 automatically included by every Makefile.
1382 </ListItem></VarListEntry>
1384 <Term><Literal>binary-dist</Literal>:</Term>
1387 make a binary distribution. This is the
1388 target we use to build the binary distributions of GHC and Happy.
1390 </ListItem></VarListEntry>
1392 <Term><Literal>dist</Literal>:</Term>
1395 make a source distribution. You must be in a
1396 linked build tree to make this target.
1398 </ListItem></VarListEntry>
1403 Most <Filename>Makefile</Filename>s have targets other than these. You can discover them by looking in the <Filename>Makefile</Filename> itself.
1409 <title>Using a project from the build tree</title>
1411 If you want to build GHC (say) and just use it direct from the build
1412 tree without doing <literal>make install</literal> first, you can run
1413 the in-place driver script:
1414 <filename>ghc/driver/ghc-inplace</filename>.
1417 <para> Do <emphasis>NOT</emphasis> use
1418 <filename>ghc/driver/ghc</filename>, or
1419 <filename>ghc/driver/ghc-4.xx</filename>, as these are the scripts
1420 intended for installation, and contain hard-wired paths to the
1421 installed libraries, rather than the libraries in the build tree.
1425 Happy can similarly be run from the build tree, using
1426 <filename>happy/src/happy-inplace</filename>.
1431 <Title>Fast Making <IndexTerm><Primary>fastmake</Primary></IndexTerm>
1432 <IndexTerm><Primary>dependencies, omitting</Primary></IndexTerm>
1433 <IndexTerm><Primary>FAST, makefile
1434 variable</Primary></IndexTerm></Title>
1437 Sometimes the dependencies get in the way: if you've made a small
1438 change to one file, and you're absolutely sure that it won't affect
1439 anything else, but you know that <Command>make</Command> is going to rebuild everything
1440 anyway, the following hack may be useful:
1452 This tells the make system to ignore dependencies and just build what
1453 you tell it to. In other words, it's equivalent to temporarily
1454 removing the <Filename>.depend</Filename> file in the current directory (where
1455 <Command>mkdependHS</Command> and friends store their dependency information).
1459 A bit of history: GHC used to come with a <Command>fastmake</Command> script that did
1460 the above job, but GNU make provides the features we need to do it
1461 without resorting to a script. Also, we've found that fastmaking is
1462 less useful since the advent of GHC's recompilation checker (see the
1463 User's Guide section on "Separate Compilation").
1471 <Title>The <Filename>Makefile</Filename> architecture
1472 <IndexTerm><Primary>makefile architecture</Primary></IndexTerm></Title>
1475 <Command>make</Command> is great if everything works—you type <Command>gmake install</Command> and
1476 lo! the right things get compiled and installed in the right places.
1477 Our goal is to make this happen often, but somehow it often doesn't;
1478 instead some weird error message eventually emerges from the bowels of
1479 a directory you didn't know existed.
1483 The purpose of this section is to give you a road-map to help you figure
1484 out what is going right and what is going wrong.
1488 <Title>A small project</Title>
1491 To get started, let us look at the <Filename>Makefile</Filename> for an imaginary small
1492 <Literal>fptools</Literal> project, <Literal>small</Literal>. Each project in <Literal>fptools</Literal> has its own
1493 directory in <Constant>FPTOOLS_TOP</Constant>, so the <Literal>small</Literal> project will have its own
1494 directory <Constant>FPOOLS_TOP/small/</Constant>. Inside the <Filename>small/</Filename> directory there
1495 will be a <Filename>Makefile</Filename>, looking something like this:
1499 <IndexTerm><Primary>Makefile, minimal</Primary></IndexTerm>
1502 # Makefile for fptools project "small"
1505 include $(TOP)/mk/boilerplate.mk
1507 SRCS = $(wildcard *.lhs) $(wildcard *.c)
1510 include $(TOP)/target.mk
1516 This <Filename>Makefile</Filename> has three sections:
1525 The first section includes
1529 One of the most important
1530 features of GNU <Command>make</Command> that we use is the ability for a <Filename>Makefile</Filename> to
1531 include another named file, very like <Command>cpp</Command>'s <Literal>#include</Literal>
1536 a file of ``boilerplate'' code from the level
1537 above (which in this case will be
1538 <Filename><Constant>FPTOOLS_TOP</Constant>/mk/boilerplate.mk</Filename><IndexTerm><Primary>boilerplate.mk</Primary></IndexTerm>). As its name
1539 suggests, <Filename>boilerplate.mk</Filename> consists of a large quantity of standard
1540 <Filename>Makefile</Filename> code. We discuss this boilerplate in more detail in
1541 <XRef LinkEnd="sec-boiler">.
1542 <IndexTerm><Primary>include, directive in Makefiles</Primary></IndexTerm>
1543 <IndexTerm><Primary>Makefile inclusion</Primary></IndexTerm>
1545 Before the <Literal>include</Literal> statement, you must define the <Command>make</Command> variable
1546 <Constant>TOP</Constant><IndexTerm><Primary>TOP</Primary></IndexTerm> to be the directory containing the <Filename>mk</Filename> directory in
1547 which the <Filename>boilerplate.mk</Filename> file is. It is <Emphasis>not</Emphasis> OK to simply say
1551 include ../mk/boilerplate.mk # NO NO NO
1555 Why? Because the <Filename>boilerplate.mk</Filename> file needs to know where it is, so
1556 that it can, in turn, <Literal>include</Literal> other files. (Unfortunately, when an
1557 <Literal>include</Literal>d file does an <Literal>include</Literal>, the filename is treated relative to
1558 the directory in which <Command>gmake</Command> is being run, not the directory in
1559 which the <Literal>include</Literal>d sits.) In general, <Emphasis>every file <Filename>foo.mk</Filename>
1560 assumes that <Filename><Constant>$(TOP)</Constant>/mk/foo.mk</Filename> refers to itself.</Emphasis> It is up to the
1561 <Filename>Makefile</Filename> doing the <Literal>include</Literal> to ensure this is the case.
1563 Files intended for inclusion in other <Filename>Makefile</Filename>s are written to have
1564 the following property: <Emphasis>after <Filename>foo.mk</Filename> is <Literal>include</Literal>d, it leaves
1565 <Constant>TOP</Constant> containing the same value as it had just before the <Literal>include</Literal>
1566 statement</Emphasis>. In our example, this invariant guarantees that the
1567 <Literal>include</Literal> for <Filename>target.mk</Filename> will look in the same directory as that for
1568 <Filename>boilerplate.mk</Filename>.
1575 The second section defines the following standard <Command>make</Command>
1576 variables: <Constant>SRCS</Constant><IndexTerm><Primary>SRCS</Primary></IndexTerm> (the source files from which is to be
1577 built), and <Constant>HS_PROG</Constant><IndexTerm><Primary>HS_PROG</Primary></IndexTerm> (the executable binary to be
1578 built). We will discuss in more detail what the ``standard
1579 variables'' are, and how they affect what happens, in <XRef LinkEnd="sec-targets">.
1581 The definition for <Constant>SRCS</Constant> uses the useful GNU <Command>make</Command> construct
1582 <Literal>$(wildcard $pat$)</Literal><IndexTerm><Primary>wildcard</Primary></IndexTerm>, which expands to a list of all
1583 the files matching the pattern <Literal>pat</Literal> in the current directory. In
1584 this example, <Constant>SRCS</Constant> is set to the list of all the <Filename>.lhs</Filename> and <Filename>.c</Filename>
1585 files in the directory. (Let's suppose there is one of each,
1586 <Filename>Foo.lhs</Filename> and <Filename>Baz.c</Filename>.)
1593 The last section includes a second file of standard code,
1594 called <Filename>target.mk</Filename><IndexTerm><Primary>target.mk</Primary></IndexTerm>. It contains the rules that tell
1595 <Command>gmake</Command> how to make the standard targets (<Xref LinkEnd="sec-standard-targets">). Why, you ask,
1596 can't this standard code be part of <Filename>boilerplate.mk</Filename>? Good question.
1597 We discuss the reason later, in <Xref LinkEnd="sec-boiler-arch">.
1599 You do not <Emphasis>have</Emphasis> to <Literal>include</Literal> the <Filename>target.mk</Filename> file. Instead, you
1600 can write rules of your own for all the standard targets. Usually,
1601 though, you will find quite a big payoff from using the canned rules
1602 in <Filename>target.mk</Filename>; the price tag is that you have to understand what
1603 canned rules get enabled, and what they do (<Xref LinkEnd="sec-targets">).
1613 In our example <Filename>Makefile</Filename>, most of the work is done by the two
1614 <Literal>include</Literal>d files. When you say <Command>gmake all</Command>, the following things
1624 <Command>gmake</Command> figures out that the object files are <Filename>Foo.o</Filename> and
1625 <Filename>Baz.o</Filename>.
1632 It uses a boilerplate pattern rule to compile <Filename>Foo.lhs</Filename> to
1633 <Filename>Foo.o</Filename> using a Haskell compiler. (Which one? That is set in the
1634 build configuration.)
1641 It uses another standard pattern rule to compile <Filename>Baz.c</Filename> to
1642 <Filename>Baz.o</Filename>, using a C compiler. (Ditto.)
1649 It links the resulting <Filename>.o</Filename> files together to make <Literal>small</Literal>,
1650 using the Haskell compiler to do the link step. (Why not use <Command>ld</Command>?
1651 Because the Haskell compiler knows what standard libraries to link in.
1652 How did <Command>gmake</Command> know to use the Haskell compiler to do the link,
1653 rather than the C compiler? Because we set the variable <Constant>HS_PROG</Constant>
1654 rather than <Constant>C_PROG</Constant>.)
1664 All <Filename>Makefile</Filename>s should follow the above three-section format.
1670 <Title>A larger project</Title>
1673 Larger projects are usually structured into a number of sub-directories,
1674 each of which has its own <Filename>Makefile</Filename>. (In very large projects, this
1675 sub-structure might be iterated recursively, though that is rare.)
1676 To give you the idea, here's part of the directory structure for
1677 the (rather large) GHC project:
1690 ...source files for documentation...
1693 ...source files for driver...
1696 parser/...source files for parser...
1697 renamer/...source files for renamer...
1704 The sub-directories <Filename>docs</Filename>, <Filename>driver</Filename>, <Filename>compiler</Filename>, and so on, each
1705 contains a sub-component of GHC, and each has its own <Filename>Makefile</Filename>.
1706 There must also be a <Filename>Makefile</Filename> in <Filename><Constant>$(FPTOOLS_TOP)</Constant>/ghc</Filename>. It does most
1707 of its work by recursively invoking <Command>gmake</Command> on the <Filename>Makefile</Filename>s in the
1708 sub-directories. We say that <Filename>ghc/Makefile</Filename> is a <Emphasis>non-leaf
1709 <Filename>Makefile</Filename></Emphasis>, because it does little except organise its children,
1710 while the <Filename>Makefile</Filename>s in the sub-directories are all <Emphasis>leaf
1711 <Filename>Makefile</Filename>s</Emphasis>. (In principle the sub-directories might themselves
1712 contain a non-leaf <Filename>Makefile</Filename> and several sub-sub-directories, but
1713 that does not happen in GHC.)
1717 The <Filename>Makefile</Filename> in <Filename>ghc/compiler</Filename> is considered a leaf <Filename>Makefile</Filename> even
1718 though the <Filename>ghc/compiler</Filename> has sub-directories, because these sub-directories
1719 do not themselves have <Filename>Makefile</Filename>s in them. They are just used to structure
1720 the collection of modules that make up GHC, but all are managed by the
1721 single <Filename>Makefile</Filename> in <Filename>ghc/compiler</Filename>.
1725 You will notice that <Filename>ghc/</Filename> also contains a directory <Filename>ghc/mk/</Filename>. It
1726 contains GHC-specific <Filename>Makefile</Filename> boilerplate code. More precisely:
1735 <Filename>ghc/mk/boilerplate.mk</Filename> is included at the top of
1736 <Filename>ghc/Makefile</Filename>, and of all the leaf <Filename>Makefile</Filename>s in the
1737 sub-directories. It in turn <Literal>include</Literal>s the main boilerplate file
1738 <Filename>mk/boilerplate.mk</Filename>.
1746 <Filename>ghc/mk/target.mk</Filename> is <Literal>include</Literal>d at the bottom of
1747 <Filename>ghc/Makefile</Filename>, and of all the leaf <Filename>Makefile</Filename>s in the
1748 sub-directories. It in turn <Literal>include</Literal>s the file <Filename>mk/target.mk</Filename>.
1758 So these two files are the place to look for GHC-wide customisation
1759 of the standard boilerplate.
1764 <Sect2 id="sec-boiler-arch">
1765 <Title>Boilerplate architecture
1766 <IndexTerm><Primary>boilerplate architecture</Primary></IndexTerm>
1770 Every <Filename>Makefile</Filename> includes a <Filename>boilerplate.mk</Filename><IndexTerm><Primary>boilerplate.mk</Primary></IndexTerm> file
1771 at the top, and <Filename>target.mk</Filename><IndexTerm><Primary>target.mk</Primary></IndexTerm> file at the bottom. In
1772 this section we discuss what is in these files, and why there have to
1773 be two of them. In general:
1782 <Filename>boilerplate.mk</Filename> consists of:
1788 <Emphasis>Definitions of millions of <Command>make</Command> variables</Emphasis> that
1789 collectively specify the build configuration. Examples:
1790 <Constant>HC_OPTS</Constant><IndexTerm><Primary>HC_OPTS</Primary></IndexTerm>, the options to feed to the Haskell compiler;
1791 <Constant>NoFibSubDirs</Constant><IndexTerm><Primary>NoFibSubDirs</Primary></IndexTerm>, the sub-directories to enable within the
1792 <Literal>nofib</Literal> project; <Constant>GhcWithHc</Constant><IndexTerm><Primary>GhcWithHc</Primary></IndexTerm>, the name of the Haskell
1793 compiler to use when compiling GHC in the <Literal>ghc</Literal> project.
1799 <Emphasis>Standard pattern rules</Emphasis> that tell <Command>gmake</Command> how to construct one
1807 <Filename>boilerplate.mk</Filename> needs to be <Literal>include</Literal>d at the <Emphasis>top</Emphasis>
1808 of each <Filename>Makefile</Filename>, so that the user can replace the
1809 boilerplate definitions or pattern rules by simply giving a new
1810 definition or pattern rule in the <Filename>Makefile</Filename>. <Command>gmake</Command>
1811 simply takes the last definition as the definitive one.
1813 Instead of <Emphasis>replacing</Emphasis> boilerplate definitions, it is also quite
1814 common to <Emphasis>augment</Emphasis> them. For example, a <Filename>Makefile</Filename> might say:
1822 thereby adding ``<Option>-O</Option>'' to the end of <Constant>SRC_HC_OPTS</Constant><IndexTerm><Primary>SRC_HC_OPTS</Primary></IndexTerm>.
1829 <Filename>target.mk</Filename> contains <Command>make</Command> rules for the standard
1830 targets described in <Xref LinkEnd="sec-standard-targets">. These rules are selectively included,
1831 depending on the setting of certain <Command>make</Command> variables. These
1832 variables are usually set in the middle section of the
1833 <Filename>Makefile</Filename> between the two <Literal>include</Literal>s.
1835 <Filename>target.mk</Filename> must be included at the end (rather than being part of
1836 <Filename>boilerplate.mk</Filename>) for several tiresome reasons:
1843 <Command>gmake</Command> commits target and dependency lists earlier than
1844 it should. For example, <FIlename>target.mk</FIlename> has a rule that looks like
1849 $(HS_PROG) : $(OBJS)
1850 $(HC) $(LD_OPTS) $< -o $@
1854 If this rule was in <Filename>boilerplate.mk</Filename> then <Constant>$(HS_PROG)</Constant><IndexTerm><Primary>HS_PROG</Primary></IndexTerm>
1855 and <Constant>$(OBJS)</Constant><IndexTerm><Primary>OBJS</Primary></IndexTerm> would not have their final values at the
1856 moment <Command>gmake</Command> encountered the rule. Alas, <Command>gmake</Command> takes a snapshot
1857 of their current values, and wires that snapshot into the rule. (In
1858 contrast, the commands executed when the rule ``fires'' are only
1859 substituted at the moment of firing.) So, the rule must follow the
1860 definitions given in the <Filename>Makefile</Filename> itself.
1867 Unlike pattern rules, ordinary rules cannot be overriden or
1868 replaced by subsequent rules for the same target (at least, not without an
1869 error message). Including ordinary rules in <Filename>boilerplate.mk</Filename> would
1870 prevent the user from writing rules for specific targets in specific cases.
1877 There are a couple of other reasons I've forgotten, but it doesn't
1893 <Sect2 id="sec-boiler">
1894 <Title>The main <Filename>mk/boilerplate.mk</Filename> file
1896 <IndexTerm><Primary>boilerplate.mk</Primary></IndexTerm></Title>
1899 If you look at <Filename><Constant>$(FPTOOLS_TOP)</Constant>/mk/boilerplate.mk</Filename> you will find
1900 that it consists of the following sections, each held in a separate
1908 <Term><Filename>config.mk</Filename><IndexTerm><Primary>config.mk</Primary></IndexTerm></Term>
1911 is the build configuration file we
1912 discussed at length in <Xref LinkEnd="sec-build-config">.
1914 </ListItem></VarListEntry>
1916 <Term><Filename>paths.mk</Filename><IndexTerm><Primary>paths.mk</Primary></IndexTerm></Term>
1919 defines <Command>make</Command> variables for
1920 pathnames and file lists. In particular, it gives definitions for:
1927 <Term><Constant>SRCS</Constant><IndexTerm><Primary>SRCS</Primary></IndexTerm>:</Term>
1930 all source files in the current directory.
1932 </ListItem></VarListEntry>
1934 <Term><Constant>HS_SRCS</Constant><IndexTerm><Primary>HS_SRCS</Primary></IndexTerm>:</Term>
1937 all Haskell source files in the current directory.
1938 It is derived from <Constant>$(SRCS)</Constant>, so if you override <Constant>SRCS</Constant> with a new value
1939 <Constant>HS_SRCS</Constant> will follow suit.
1941 </ListItem></VarListEntry>
1943 <Term><Constant>C_SRCS</Constant><IndexTerm><Primary>C_SRCS</Primary></IndexTerm>:</Term>
1946 similarly for C source files.
1948 </ListItem></VarListEntry>
1950 <Term><Constant>HS_OBJS</Constant><IndexTerm><Primary>HS_OBJS</Primary></IndexTerm>:</Term>
1953 the <Filename>.o</Filename> files derived from <Constant>$(HS_SRCS)</Constant>.
1955 </ListItem></VarListEntry>
1957 <Term><Constant>C_OBJS</Constant><IndexTerm><Primary>C_OBJS</Primary></IndexTerm>:</Term>
1960 similarly for <Constant>$(C_SRCS)</Constant>.
1962 </ListItem></VarListEntry>
1964 <Term><Constant>OBJS</Constant><IndexTerm><Primary>OBJS</Primary></IndexTerm>:</Term>
1967 the concatenation of <Constant>$(HS_OBJS)</Constant> and <Constant>$(C_OBJS)</Constant>.
1969 </ListItem></VarListEntry>
1974 Any or all of these definitions can easily be overriden by giving new
1975 definitions in your <Filename>Makefile</Filename>. For example, if there are things in
1976 the current directory that look like source files but aren't, then
1977 you'll need to set <Constant>SRCS</Constant> manually in your <Filename>Makefile</Filename>. The other
1978 definitions will then work from this new definition.
1982 What, exactly, does <Filename>paths.mk</Filename> consider a ``source file'' to be? It's
1983 based on the file's suffix (e.g. <Filename>.hs</Filename>, <Filename>.lhs</Filename>, <Filename>.c</Filename>, <Filename>.lc</Filename>, etc), but
1984 this is the kind of detail that changes, so rather than
1985 enumerate the source suffices here the best thing to do is to look in
1986 <Filename>paths.mk</Filename>.
1988 </ListItem></VarListEntry>
1990 <Term><Filename>opts.mk</Filename><IndexTerm><Primary>opts.mk</Primary></IndexTerm></Term>
1993 defines <Command>make</Command> variables for option
1994 strings to pass to each program. For example, it defines
1995 <Constant>HC_OPTS</Constant><IndexTerm><Primary>HC_OPTS</Primary></IndexTerm>, the option strings to pass to the Haskell
1996 compiler. See <Xref LinkEnd="sec-suffix">.
1998 </ListItem></VarListEntry>
2000 <Term><Filename>suffix.mk</Filename><IndexTerm><Primary>suffix.mk</Primary></IndexTerm></Term>
2003 defines standard pattern rules—see <Xref LinkEnd="sec-suffix">.
2005 </ListItem></VarListEntry>
2010 Any of the variables and pattern rules defined by the boilerplate file
2011 can easily be overridden in any particular <Filename>Makefile</Filename>, because the
2012 boilerplate <Literal>include</Literal> comes first. Definitions after this <Literal>include</Literal>
2013 directive simply override the default ones in <Filename>boilerplate.mk</Filename>.
2018 <Sect2 id="sec-suffix">
2019 <Title>Pattern rules and options
2021 <IndexTerm><Primary>Pattern rules</Primary></IndexTerm></Title>
2024 The file <Filename>suffix.mk</Filename><IndexTerm><Primary>suffix.mk</Primary></IndexTerm> defines standard <Emphasis>pattern
2025 rules</Emphasis> that say how to build one kind of file from another, for
2026 example, how to build a <Filename>.o</Filename> file from a <Filename>.c</Filename> file. (GNU <Command>make</Command>'s
2027 <Emphasis>pattern rules</Emphasis> are more powerful and easier to use than Unix
2028 <Command>make</Command>'s <Emphasis>suffix rules</Emphasis>.)
2032 Almost all the rules look something like this:
2040 $(CC) $(CC_OPTS) -c $< -o $@
2046 Here's how to understand the rule. It says that
2047 <Emphasis>something</Emphasis><Filename>.o</Filename> (say <Filename>Foo.o</Filename>) can be built from
2048 <Emphasis>something</Emphasis><Filename>.c</Filename> (<Filename>Foo.c</Filename>), by invoking the C compiler
2049 (path name held in <Constant>$(CC)</Constant>), passing to it the options
2050 <Constant>$(CC_OPTS)</Constant> and the rule's dependent file of the rule
2051 <Literal>$<</Literal> (<Filename>Foo.c</Filename> in this case), and putting the result in
2052 the rule's target <Literal>$@</Literal> (<Filename>Foo.o</Filename> in this case).
2056 Every program is held in a <Command>make</Command> variable defined in
2057 <Filename>mk/config.mk</Filename>—look in <Filename>mk/config.mk</Filename> for the
2058 complete list. One important one is the Haskell compiler, which is
2059 called <Constant>$(HC)</Constant>.
2063 Every program's options are are held in a <Command>make</Command> variables called
2064 <Constant><prog>_OPTS</Constant>. the <Constant><prog>_OPTS</Constant> variables are defined in
2065 <Filename>mk/opts.mk</Filename>. Almost all of them are defined like this:
2071 CC_OPTS = $(SRC_CC_OPTS) $(WAY$(_way)_CC_OPTS) $($*_CC_OPTS) $(EXTRA_CC_OPTS)
2077 The four variables from which <Constant>CC_OPTS</Constant> is built have the following meaning:
2084 <Term><Constant>SRC_CC_OPTS</Constant><IndexTerm><Primary>SRC_CC_OPTS</Primary></IndexTerm>:</Term>
2087 options passed to all C
2090 </ListItem></VarListEntry>
2092 <Term><Constant>WAY_<way>_CC_OPTS</Constant>:</Term>
2096 compilations for way <Literal><way></Literal>. For example,
2097 <Constant>WAY_mp_CC_OPTS</Constant> gives options to pass to the C compiler when
2098 compiling way <Literal>mp</Literal>. The variable <Constant>WAY_CC_OPTS</Constant> holds
2099 options to pass to the C compiler when compiling the standard way.
2100 (<Xref LinkEnd="sec-ways"> dicusses multi-way
2103 </ListItem></VarListEntry>
2105 <Term><Constant><module>_CC_OPTS</Constant>:</Term>
2109 pass to the C compiler that are specific to module <Literal><module></Literal>. For example, <Constant>SMap_CC_OPTS</Constant> gives the specific options
2110 to pass to the C compiler when compiling <Filename>SMap.c</Filename>.
2112 </ListItem></VarListEntry>
2114 <Term><Constant>EXTRA_CC_OPTS</Constant><IndexTerm><Primary>EXTRA_CC_OPTS</Primary></IndexTerm>:</Term>
2117 extra options to pass to all
2118 C compilations. This is intended for command line use, thus:
2124 gmake libHS.a EXTRA_CC_OPTS="-v"
2128 </ListItem></VarListEntry>
2134 <Sect2 id="sec-targets">
2135 <Title>The main <Filename>mk/target.mk</Filename> file
2137 <IndexTerm><Primary>target.mk</Primary></IndexTerm></Title>
2140 <Filename>target.mk</Filename> contains canned rules for all the standard targets
2141 described in <Xref LinkEnd="sec-standard-targets">. It is complicated by the fact that you don't want all of
2142 these rules to be active in every <Filename>Makefile</Filename>. Rather than have a
2143 plethora of tiny files which you can include selectively, there is a
2144 single file, <Filename>target.mk</Filename>, which selectively includes rules based on
2145 whether you have defined certain variables in your <Filename>Makefile</Filename>. This
2146 section explains what rules you get, what variables control them, and
2147 what the rules do. Hopefully, you will also get enough of an idea of
2148 what is supposed to happen that you can read and understand any weird
2149 special cases yourself.
2156 <Term><Constant>HS_PROG</Constant><IndexTerm><Primary>HS_PROG</Primary></IndexTerm>.</Term>
2159 If <Constant>HS_PROG</Constant> is defined, you get
2160 rules with the following targets:
2164 <Term><Filename>HS_PROG</Filename><IndexTerm><Primary>HS_PROG</Primary></IndexTerm></Term>
2167 itself. This rule links <Constant>$(OBJS)</Constant>
2168 with the Haskell runtime system to get an executable called
2169 <Constant>$(HS_PROG)</Constant>.
2171 </ListItem></VarListEntry>
2173 <Term><Literal>install</Literal><IndexTerm><Primary>install</Primary></IndexTerm></Term>
2176 installs <Constant>$(HS_PROG)</Constant>
2177 in <Constant>$(bindir)</Constant>.
2179 </ListItem></VarListEntry>
2182 </ListItem></VarListEntry>
2184 <Term><Constant>C_PROG</Constant><IndexTerm><Primary>C_PROG</Primary></IndexTerm></Term>
2187 is similar to <Constant>HS_PROG</Constant>, except that
2188 the link step links <Constant>$(C_OBJS)</Constant> with the C runtime system.
2190 </ListItem></VarListEntry>
2192 <Term><Constant>LIBRARY</Constant><IndexTerm><Primary>LIBRARY</Primary></IndexTerm></Term>
2195 is similar to <Constant>HS_PROG</Constant>, except that
2196 it links <Constant>$(LIB_OBJS)</Constant> to make the library archive <Constant>$(LIBRARY)</Constant>, and
2197 <Literal>install</Literal> installs it in <Constant>$(libdir)</Constant>.
2199 </ListItem></VarListEntry>
2201 <Term><Constant>LIB_DATA</Constant><IndexTerm><Primary>LIB_DATA</Primary></IndexTerm></Term>
2206 </ListItem></VarListEntry>
2208 <Term><Constant>LIB_EXEC</Constant><IndexTerm><Primary>LIB_EXEC</Primary></IndexTerm></Term>
2213 </ListItem></VarListEntry>
2215 <Term><Constant>HS_SRCS</Constant><IndexTerm><Primary>HS_SRCS</Primary></IndexTerm>, <Constant>C_SRCS</Constant><IndexTerm><Primary>C_SRCS</Primary></IndexTerm>.</Term>
2218 If <Constant>HS_SRCS</Constant>
2219 is defined and non-empty, a rule for the target <Literal>depend</Literal> is included,
2220 which generates dependency information for Haskell programs.
2221 Similarly for <Constant>C_SRCS</Constant>.
2223 </ListItem></VarListEntry>
2228 All of these rules are ``double-colon'' rules, thus
2234 install :: $(HS_PROG)
2235 ...how to install it...
2241 GNU <Command>make</Command> treats double-colon rules as separate entities. If there
2242 are several double-colon rules for the same target it takes each in
2243 turn and fires it if its dependencies say to do so. This means that
2244 you can, for example, define both <Constant>HS_PROG</Constant> and <Constant>LIBRARY</Constant>, which will
2245 generate two rules for <Literal>install</Literal>. When you type <Command>gmake install</Command> both
2246 rules will be fired, and both the program and the library will be
2247 installed, just as you wanted.
2252 <Sect2 id="sec-subdirs">
2255 <IndexTerm><Primary>recursion, in makefiles</Primary></IndexTerm>
2256 <IndexTerm><Primary>Makefile, recursing into subdirectories</Primary></IndexTerm></Title>
2259 In leaf <Filename>Makefile</Filename>s the variable <Constant>SUBDIRS</Constant><IndexTerm><Primary>SUBDIRS</Primary></IndexTerm> is undefined.
2260 In non-leaf <Filename>Makefile</Filename>s, <Constant>SUBDIRS</Constant> is set to the list of
2261 sub-directories that contain subordinate <Filename>Makefile</Filename>s. <Emphasis>It is up to
2262 you to set <Constant>SUBDIRS</Constant> in the <Filename>Makefile</Filename>.</Emphasis> There is no automation here—<Constant>SUBDIRS</Constant> is too important to automate.
2266 When <Constant>SUBDIRS</Constant> is defined, <Filename>target.mk</Filename> includes a rather
2267 neat rule for the standard targets (<Xref LinkEnd="sec-standard-targets"> that simply invokes
2268 <Command>make</Command> recursively in each of the sub-directories.
2272 <Emphasis>These recursive invocations are guaranteed to occur in the order
2273 in which the list of directories is specified in <Constant>SUBDIRS</Constant>. </Emphasis>This
2274 guarantee can be important. For example, when you say <Command>gmake boot</Command> it
2275 can be important that the recursive invocation of <Command>make boot</Command> is done
2276 in one sub-directory (the include files, say) before another (the
2277 source files). Generally, put the most independent sub-directory
2278 first, and the most dependent last.
2283 <Sect2 id="sec-ways">
2284 <Title>Way management
2286 <IndexTerm><Primary>way management</Primary></IndexTerm></Title>
2289 We sometimes want to build essentially the same system in several
2290 different ``ways''. For example, we want to build GHC's <Literal>Prelude</Literal>
2291 libraries with and without profiling, with and without concurrency,
2292 and so on, so that there is an appropriately-built library archive to
2293 link with when the user compiles his program. It would be possible to
2294 have a completely separate build tree for each such ``way'', but it
2295 would be horribly bureaucratic, especially since often only parts of
2296 the build tree need to be constructed in multiple ways.
2300 Instead, the <Filename>target.mk</Filename><IndexTerm><Primary>target.mk</Primary></IndexTerm> contains some clever magic to
2301 allow you to build several versions of a system; and to control
2302 locally how many versions are built and how they differ. This section
2307 The files for a particular way are distinguished by munging the
2308 suffix. The ``normal way'' is always built, and its files have the
2309 standard suffices <Filename>.o</Filename>, <Filename>.hi</Filename>, and so on. In addition, you can build
2310 one or more extra ways, each distinguished by a <Emphasis>way tag</Emphasis>. The
2311 object files and interface files for one of these extra ways are
2312 distinguished by their suffix. For example, way <Literal>mp</Literal> has files
2313 <Filename>.mp_o</Filename> and <Filename>.mp_hi</Filename>. Library archives have their way tag the other
2314 side of the dot, for boring reasons; thus, <Filename>libHS_mp.a</Filename>.
2318 A <Command>make</Command> variable called <Constant>way</Constant> holds the current way tag. <Emphasis><Constant>way</Constant>
2319 is only ever set on the command line of a recursive invocation of
2320 <Command>gmake</Command>.</Emphasis> It is never set inside a <Filename>Makefile</Filename>. So it is a global
2321 constant for any one invocation of <Command>gmake</Command>. Two other <Command>make</Command>
2322 variables, <Constant>way_</Constant> and <Constant>_way</Constant> are immediately derived from <Constant>$(way)</Constant> and
2323 never altered. If <Constant>way</Constant> is not set, then neither are <Constant>way_</Constant> and
2324 <Constant>_way</Constant>, and the invocation of <Command>make</Command> will build the ``normal way''.
2325 If <Constant>way</Constant> is set, then the other two variables are set in sympathy.
2326 For example, if <Constant>$(way)</Constant> is ``<Literal>mp</Literal>'', then <Constant>way_</Constant> is set to ``<Literal>mp_</Literal>''
2327 and <Constant>_way</Constant> is set to ``<Literal>_mp</Literal>''. These three variables are then used
2328 when constructing file names.
2332 So how does <Command>make</Command> ever get recursively invoked with <Constant>way</Constant> set? There
2333 are two ways in which this happens:
2342 For some (but not all) of the standard targets, when in a leaf
2343 sub-directory, <Command>make</Command> is recursively invoked for each way tag in
2344 <Constant>$(WAYS)</Constant>. You set <Constant>WAYS</Constant> to the list of way tags you want these
2345 targets built for. The mechanism here is very much like the recursive
2346 invocation of <Command>make</Command> in sub-directories (<Xref LinkEnd="sec-subdirs">).
2348 It is up to you to set <Constant>WAYS</Constant> in your <Filename>Makefile</Filename>; this is how you
2349 control what ways will get built.
2355 For a useful collection of
2356 targets (such as <Filename>libHS_mp.a</Filename>, <Filename>Foo.mp_o</Filename>) there is a rule which
2357 recursively invokes <Command>make</Command> to make the specified target, setting the
2358 <Constant>way</Constant> variable. So if you say <Command>gmake Foo.mp_o</Command> you should see a
2359 recursive invocation <Command>gmake Foo.mp_o way=mp</Command>, and <Emphasis>in this
2360 recursive invocation the pattern rule for compiling a Haskell file
2361 into a <Filename>.o</Filename> file will match</Emphasis>. The key pattern rules (in <Filename>suffix.mk</Filename>)
2367 $(HC) $(HC_OPTS) $< -o $@
2382 <Title>When the canned rule isn't right</Title>
2385 Sometimes the canned rule just doesn't do the right thing. For
2386 example, in the <Literal>nofib</Literal> suite we want the link step to print out
2387 timing information. The thing to do here is <Emphasis>not</Emphasis> to define
2388 <Constant>HS_PROG</Constant> or <Constant>C_PROG</Constant>, and instead define a special purpose rule in
2389 your own <Filename>Makefile</Filename>. By using different variable names you will avoid
2390 the canned rules being included, and conflicting with yours.
2397 <Sect1 id="sec-booting-from-C">
2398 <Title>Booting/porting from C (<Filename>.hc</Filename>) files
2400 <IndexTerm><Primary>building GHC from .hc files</Primary></IndexTerm>
2401 <IndexTerm><Primary>booting GHC from .hc files</Primary></IndexTerm>
2402 <IndexTerm><Primary>porting GHC</Primary></IndexTerm></Title>
2405 This section is for people trying to get GHC going by using the
2406 supplied intermediate C (<Filename>.hc</Filename>) files. This would probably be because
2407 no binaries have been provided, or because the machine is not ``fully
2412 The intermediate C files are normally made available together with a
2413 source release, please check the announce message for exact directions
2414 of where to find them. If we haven't made them available or you
2415 can't find them, please ask.
2419 Assuming you've got them, unpack them on top of a fresh source tree.
2420 Then follow the `normal' instructions in <Xref LinkEnd="sec-building-from-source"> for setting
2421 up a build tree. When you invoke the configure script, you'll have
2422 to tell the script about your intentions:
2428 foo% ./configure --enable-hc-boot
2431 <IndexTerm><Primary>--enable-hc-boot</Primary></IndexTerm>
2432 <IndexTerm><Primary>--disable-hc-boot</Primary></IndexTerm>
2436 Assuming it configures OK and you don't need to create <Filename>mk/build.mk</Filename>
2437 for any other purposes, the next step is to proceed with a <Command>make boot</Command>
2438 followed by <Command>make all</Command>. At the successful completion of <Command>make all</Command>,
2439 you should end up with a binary of the compiler proper,
2440 <Filename>ghc/compiler/hsc</Filename>, plus archives (but no <Filename>.hi</Filename> files!) of the prelude
2441 libraries. To generate the Prelude interface files (and test drive the
2442 bootstrapped compiler), re-run the <Command>configure</Command> script, but this time
2443 without the <Option>--enable-hc-boot</Option> option. After that re-create the
2444 contents of <Filename>ghc/lib</Filename>:
2461 That's the mechanics of the boot process, but, of course, if you're
2462 trying to boot on a platform that is not supported and significantly
2463 `different' from any of the supported ones, this is only the start of
2464 the adventure…(ToDo: porting tips—stuff to look out for, etc.)
2469 <Sect1 id="sec-build-pitfalls">
2470 <Title>Known pitfalls in building Glasgow Haskell
2472 <IndexTerm><Primary>problems, building</Primary></IndexTerm>
2473 <IndexTerm><Primary>pitfalls, in building</Primary></IndexTerm>
2474 <IndexTerm><Primary>building pitfalls</Primary></IndexTerm></Title>
2477 WARNINGS about pitfalls and known ``problems'':
2486 One difficulty that comes up from time to time is running out of space
2487 in <Filename>/tmp</Filename>. (It is impossible for the configuration stuff to
2488 compensate for the vagaries of different sysadmin approaches to temp
2490 <IndexTerm><Primary>tmp, running out of space in</Primary></IndexTerm>
2492 The quickest way around it is <Command>setenv TMPDIR /usr/tmp</Command><IndexTerm><Primary>TMPDIR</Primary></IndexTerm> or
2493 even <Command>setenv TMPDIR .</Command> (or the equivalent incantation with your shell
2496 The best way around it is to say
2499 export TMPDIR=<dir>
2502 in your <Filename>build.mk</Filename> file.
2503 Then GHC and the other <Literal>fptools</Literal> programs will use the appropriate directory
2512 In compiling some support-code bits, e.g., in <Filename>ghc/rts/gmp</Filename> and even
2513 in <Filename>ghc/lib</Filename>, you may get a few C-compiler warnings. We think these
2521 When compiling via C, you'll sometimes get ``warning: assignment from
2522 incompatible pointer type'' out of GCC. Harmless.
2529 Similarly, <Command>ar</Command>chiving warning messages like the following are not
2533 ar: filename GlaIOMonad__1_2s.o truncated to GlaIOMonad_
2534 ar: filename GlaIOMonad__2_2s.o truncated to GlaIOMonad_
2544 In compiling the compiler proper (in <Filename>compiler/</Filename>), you <Emphasis>may</Emphasis>
2545 get an ``Out of heap space'' error message. These can vary with the
2546 vagaries of different systems, it seems. The solution is simple:
2553 If you're compiling with GHC 4.00 or later, then the
2554 <Emphasis>maximum</Emphasis> heap size must have been reached. This
2555 is somewhat unlikely, since the maximum is set to 64M by default.
2556 Anyway, you can raise it with the
2557 <Option>-optCrts-M<size></Option> flag (add this flag to
2558 <Constant><module>_HC_OPTS</Constant>
2559 <Command>make</Command> variable in the appropriate
2560 <Filename>Makefile</Filename>).
2567 For GHC < 4.00, add a suitable <Option>-H</Option> flag to the <Filename>Makefile</Filename>, as
2576 and try again: <Command>gmake</Command>. (see <Xref LinkEnd="sec-suffix"> for information about
2577 <Constant><module>_HC_OPTS</Constant>.)
2579 Alternatively, just cut to the chase:
2583 % make EXTRA_HC_OPTS=-optCrts-M128M
2592 If you try to compile some Haskell, and you get errors from GCC about
2593 lots of things from <Filename>/usr/include/math.h</Filename>, then your GCC was
2594 mis-installed. <Command>fixincludes</Command> wasn't run when it should've been.
2596 As <Command>fixincludes</Command> is now automagically run as part of GCC installation,
2597 this bug also suggests that you have an old GCC.
2605 You <Emphasis>may</Emphasis> need to re-<Command>ranlib</Command><IndexTerm><Primary>ranlib</Primary></IndexTerm> your libraries (on Sun4s).
2609 % cd $(libdir)/ghc-x.xx/sparc-sun-sunos4
2610 % foreach i ( `find . -name '*.a' -print` ) # or other-shell equiv...
2612 ? # or, on some machines: ar s $i
2617 We'd be interested to know if this is still necessary.
2625 GHC's sources go through <Command>cpp</Command> before being compiled, and <Command>cpp</Command> varies
2626 a bit from one Unix to another. One particular gotcha is macro calls
2631 SLIT("Hello, world")
2635 Some <Command>cpp</Command>s treat the comma inside the string as separating two macro
2636 arguments, so you get
2640 :731: macro `SLIT' used with too many (2) args
2644 Alas, <Command>cpp</Command> doesn't tell you the offending file!
2646 Workaround: don't put weird things in string args to <Command>cpp</Command> macros.
2657 <Sect1 id="winbuild"><Title>Notes for building under Windows</Title>
2660 This section summarises how to get the utilities you need on your
2661 Win95/98/NT/2000 machine to use CVS and build GHC. Similar notes for installing and running GHC may be found in the user guide. In general, Win95/Win98 behave the same, and WinNT/Win2k behave the same. It is based largely on detailed advice from Sigbjørn Finne.
2665 <Sect2><Title>Installing ssh</Title>
2671 Extract the whole of <ULink URL="http://research.microsoft.com/~simonpj/ssh-1_2_26-cygwinb19.tar.gz">the ssh archive</ULink> into your <Filename>C:\</Filename> directory, and use the ``All files'' and ``User folder names'' options in WinZip extract dialogue box. This populates your <Filename>C:\usr\local</Filename> tree.
2677 Extract <ULink URL="http://research.microsoft.com/~simonpj/cygwinb19.dll.zip">cygwinb19.dll</ULink> into <Filename>/usr/local/bin</Filename>. The current version
2678 of Cywin is b20, but this version of ssh was compiled with b19.
2684 On a Win2k machine, open up a bash and do
2689 foo$ mkpasswd -l > passwd
2693 Check that your login entry is on the first line
2694 of that file. If not, move it to the top. It's OK
2695 for 'Administrator' to be the first entry, assuming you are one.
2699 However, Win9x doesn't support the calls that <Command>mkpasswd</Command> relies on
2700 (e.g., <Function>NetUserEnum</Function>). If you run <Command>mkpasswd</Command> you
2705 linked to missing export netapi32.dll:NetUserEnum
2709 The passwd file is used
2710 by ssh in a fairly rudimentary manner, so I'd simply
2711 synthesise/copy an existing Unix <Filename>/etc/passwd</Filename>, i.e., create
2712 an <Filename>/etc/passwd</Filename> file containing the line
2716 <login>::500:513:::/bin/sh
2720 where <Literal><login></Literal> is your login id.
2726 Generate a key, by running <Filename>c:/user/local/bin/ssh-keygen1</Filename>.
2727 This generates a public key in <Filename>.ssh/identity.pub</Filename>, and a
2728 private key in <Filename>.ssh/identity</Filename>
2732 In response to the 'Enter passphrase' question, just hit
2733 return (i.e. use an empty passphrase). The passphrase is
2734 a password that protects your private key. But it's a pain
2735 to type this passphrase everytime you use <Command>ssh</Command>, so the best
2736 thing to do is simply to protect your <Filename>.ssh</Filename> directory, and
2737 <Filename>.ssh/identity</Filename> from access by anyone else. To do this
2738 right-click your <Filename>.ssh</Filename> directory, and select Properties.
2739 If you are not on the access control list, add yourself, and
2740 give yourself full permissions (the second panel).
2741 Remove everyone else from the access control list. (Don't
2742 leave them there but deny them access, because 'they' may be
2743 a list that includes you!)
2747 If you have problems running <Command>ssh-keygen1</Command>
2748 from within <Command>bash</Command>, start up <Filename>cmd.exe</Filename> and run it as follows:
2752 c:\tmp> set CYGWIN32=tty
2753 c:\tmp> c:/user/local/bin/ssh-keygen1
2759 If you don't have an account on <Literal>cvs.haskell.org</Literal>, send
2760 your <Filename>.ssh/identity.pub</Filename> to the CVS repository administrator
2761 (currently Jeff Lewis <Email>jlewis@cse.ogi.edu</Email>). He will set up
2766 If you do have an account on <Literal>cvs.haskell.org</Literal>, use TeraTerm
2767 to logon to it. Once in, copy the
2768 key that <Command>ssh-keygen1</Command> deposited in <Filename>/.ssh/identity.pub</Filename> into
2769 your <Filename>~/.ssh/authorized_keys</Filename>. Make sure that the new version
2770 of <Filename>authorized_keys</Filename> still has 600 file permission.
2779 <Sect2><Title>Installing CVS</Title>
2786 <ULink URL="http://research.microsoft.com/~simonpj/cvs-1_10-win.zip">
2787 CVS</ULink> and, following the instructions in the <Filename>README</Filename>, copy the
2788 appropriate files into <Filename>/usr/local/bin</Filename>.
2794 From the System control panel,
2795 set the following <Emphasis>user</Emphasis> environment variables (see the GHC user guide)
2801 <Constant>HOME</Constant>: points to your home directory. This is where CVS
2802 will look for its <Filename>.cvsrc</Filename> file.
2808 <Constant>CVS_RSH</Constant>: <Filename>c:/usr/local/bin/ssh1</Filename>
2814 <Constant>CVSROOT</Constant>: <Literal>:ext:username@cvs.haskell.org:/home/cvs/root</Literal>,
2815 where <Literal>username</Literal> is your userid
2821 <Constant>CVSEDITOR</Constant>: <Filename>bin/gnuclient.exe</Filename> if you want to use an Emacs buffer for typing in those long commit messages.
2829 Put the following in <Filename>$HOME/.cvsrc</Filename>:
2840 These are the default options for the specified CVS commands,
2841 and represent better defaults than the usual ones. (Feel
2842 free to change them.)
2846 Filenames starting with "<Filename>.</Filename>" were illegal in
2847 the 8.3 DOS filesystem, but that restriction should have
2848 been lifted by now (i.e., you're using VFAT or later filesystems.) If
2849 you're still having problems creating it, don't worry; <Filename>.cvsrc</Filename> is entirely
2856 Try doing <Command>cvs co fpconfig</Command>. All being well, bytes should
2857 start to trickle through, leaving a directory <Filename>fptools</Filename>
2858 in your current directory. (You can <Command>rm</Command> it if you don't want to keep it.) The following messages appear to be harmless:
2862 setsockopt IPTOS_LOWDELAY: Invalid argument
2863 setsockopt IPTOS_THROUGHPUT: Invalid argument
2867 At this point I found that CVS tried to invoke a little dialogue with
2868 me (along the lines of `do you want to talk to this host'), but
2869 somehow bombed out. This was from a bash shell running in emacs.
2870 I solved this by invoking a Cygnus shell, and running CVS from there.
2871 Once things are dialogue free, it seems to work OK from within emacs.
2877 If you want to check out part of large tree, proceed as follows:
2881 cvs -f checkout -l papers
2887 This sequence checks out the <Literal>papers</Literal> module, but none
2888 of its sub-directories.
2889 The "<Option>-l</Option>" flag says not to check out sub-directories.
2890 The "<Option>-f</Option>" flag says not to read the <Filename>.cvsrc</Filename> file
2891 whose <Option>-P</Option> default (don't check out empty directories) is
2896 The <Command>cvs update</Command> command sucks in a named sub-directory.
2903 There is a very nice graphical front-end to CVS for Win32 platforms,
2904 with a UI that people will be familiar with, at
2905 <ULink URL="http://www.wincvs.org/">wincvs.org</ULink>.
2906 I have not tried it yet.
2912 <Sect2><Title>Installing autoconf</Title>
2915 Only required if you are doing builds from GHC's sources
2916 checked out from the CVS tree.
2922 Fetch the (standard, Unix) <Command>autoconf</Command> distribution from
2923 <ULink URL="ftp://ftp.gnu.org/gnu/autoconf">ftp.gnu.org</ULink>.
2928 Unpack it into an arbitrary directory.
2933 Make sure that the directory <Filename>/usr/local/bin</Filename> exists.
2938 Say "<Filename>./configure</Filename>".
2943 Now <Command>make install</Command>. This should put <Filename>autoheader</Filename>
2944 and <Filename>autoconf</Filename> in <Filename>/usr/local/bin</Filename>.
2950 <Command>autoheader</Command> doesn't seem to work, but you don't need it
2957 <Sect2><Title>Building GHC</Title>
2963 In the <Filename>./configure</Filename> output, ignore
2965 checking whether #! works in shell scripts...
2966 ./configure: ./conftest: No such file or directory</Literal>",
2967 and "<Literal>not updating unwritable cache ./config.cache</Literal>".
2968 Nobody knows why these happen, but they seem to be harmless.
2974 You have to run <Command>autoconf</Command> both in <Filename>fptools</Filename>
2975 and in <Filename>fptools/ghc</Filename>. If you omit the latter step you'll
2976 get an error when you run <Filename>./configure</Filename>:
2981 creating mk/config.h
2982 mk/config.h is unchanged
2984 running /bin/sh ./configure --cache-file=.././config.cache --srcdir=.
2985 ./configure: ./configure: No such file or directory
2986 configure: error: ./configure failed for ghc
2992 You need <Filename>ghc</Filename> to be in your <Constant>PATH</Constant> before you run
2993 <Command>configure</Command>. The default GHC InstallShield creates only
2994 <Filename>ghc-4.05</Filename>, so you may need to duplicate this file as <Filename>ghc</Filename>
2995 in the same directory, in order that <Command>configure</Command> will see it (or
2996 just rename <Filename>ghc-4.05</Filename> to <Filename>ghc</Filename>.
2997 And make sure that the directory is in your path.
3003 Compile <Command>happy</Command> and <Command>ghc</Command>
3004 with <Option>-static</Option>. To do this, set
3013 in your <Filename>build.mk</Filename> file.
3014 [Actually, I successfully compiled Happy without <Option>-static</Option> on Win2k, but not GHC.]