1 <!DOCTYPE Article PUBLIC "-//OASIS//DTD DocBook V3.1//EN">
3 <Article id="building-guide">
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>November 2001</PubDate>
13 <para>The Glasgow fptools suite is a collection of Functional
14 Programming related tools, including the Glasgow Haskell
15 Compiler (GHC). The source code for the whole suite is kept in
16 a single CVS repository and shares a common build and
17 installation system.</para>
19 <para>This guide is intended for people who want to build or
20 modify programs from the Glasgow <Literal>fptools</Literal>
21 suite (as distinct from those who merely want to
22 <Emphasis>run</Emphasis> them). Installation instructions are
23 now provided in the user guide.</para>
25 <para>The bulk of this guide applies to building on Unix
26 systems; see <XRef LinkEnd="winbuild"> for Windows notes.</para>
32 <sect1 id="sec-getting">
33 <title>Getting the Glasgow <Literal>fptools</Literal> suite</title>
35 <para>Building the Glasgow tools <Emphasis>can</Emphasis> be
36 complicated, mostly because there are so many permutations of
37 what/why/how, e.g., ``Build Happy with HBC, everything else with
38 GHC, leave out profiling, and test it all on the `real' NoFib
39 programs.'' Yeeps!</para>
41 <para>Happily, such complications don't apply to most people. A
42 few common ``strategies'' serve most purposes. Pick one and
43 proceed as suggested:</para>
48 <term><indexterm><primary>Binary distribution</primary></indexterm>Binary distribution.</term>
51 If your only purpose is to install some of the
52 <Literal>fptools</Literal> suite then the easiest thing to do is to
53 get a binary distribution. In the binary distribution everything is
54 pre-compiled for your particular machine architecture and operating
55 system, so all you should have to do is install the binaries and
56 libraries in suitable places. The user guide describes how to do this.
60 A binary distribution may not work for you for two reasons. First, we
61 may not have built the suite for the particular architecture/OS
62 platform you want. That may be due to lack of time and energy (in
63 which case you can get a source distribution and build from it; see
64 below). Alternatively, it may be because we haven't yet ported the
65 suite to your architecture, in which case you are considerably worse
70 The second reason a binary distribution may not be what you want is
71 if you want to read or modify the souce code.
73 </listitem></VarListEntry>
75 <term><indexterm><primary>Source distribution</primary></indexterm>Source distribution.</term>
79 platform, but (a) you like the warm fuzzy feeling of compiling things
80 yourself; (b) you want to build something ``extra''—e.g., a set of
81 libraries with strictness-analysis turned off; or (c) you want to hack
86 A source distribution contains complete sources for one or more
87 projects in the <Literal>fptools</Literal> suite. Not only that, but
88 the more awkward machine-independent steps are done for you. For
89 example, if you don't have
90 <Command>happy</Command><indexterm><primary>happy</primary></indexterm>
91 you'll find it convenient that the source distribution contains the
92 result of running <Command>happy</Command> on the parser
93 specifications. If you don't want to alter the parser then this saves
94 you having to find and install <Command>happy</Command>. You will
95 still need a working version of GHC (preferably version 4.08+) on your
96 machine in order to compile (most of) the sources, however.
99 </listitem></VarListEntry>
102 <term>The CVS repository.</term>
103 <indexterm><primary>CVS repository</primary>
106 <para>We make releases infrequently. If you want more
107 up-to-the minute (but less tested) source code then you need
108 to get access to our CVS repository.</para>
110 <para>All the <Literal>fptools</Literal> source code is held
111 in a CVS repository. CVS is a pretty good source-code
112 control system, and best of all it works over the
115 <para>The repository holds source code only. It holds no
116 mechanically generated files at all. So if you check out a
117 source tree from CVS you will need to install every utility
118 so that you can build all the derived files from
121 <para>More information about our CVS repository can be found
122 in <xref linkend="sec-cvs">.</para>
128 <term>Build GHC from intermediate C <Filename>.hc</Filename> files<indexterm><primary>hc files</primary></indexterm>:</term>
130 <para>You need a working GHC to use a source distribution.
131 What if you don't have a working GHC? Then you may be able
132 to bootstrap up from the intermediate C
133 (<filename>.hc</filename>) files that we provide. Building
134 GHC on an unsupported platform falls into this category.
135 Beware: this route is not for the faint hearted! Please see
136 <Xref LinkEnd="sec-booting-from-C">.</para>
138 <para>Once you have built GHC, you can build the other
139 Glasgow tools with it.</para>
141 <para>In theory, you can (could?) build GHC with another
142 Haskell compiler (e.g., HBC). We haven't tried to do this
143 for ages and it almost certainly doesn't work any more (for
144 tedious reasons).</para>
149 <para>If you are going to do any building from sources (either
150 from a source distribution or the CVS repository) then you need to
151 read all of this manual in detail.</para>
155 <title>Using the CVS repository</title>
157 <para>We use <ulink url="http://www.cvshome.org/">CVS</ulink> (Concurrent Version System) to keep track of our
158 sources for various software projects. CVS lets several people
159 work on the same software at the same time, allowing changes to be
160 checked in incrementally. </para>
162 <para>This section is a set of guidelines for how to use our CVS
163 repository, and will probably evolve in time. The main thing to
164 remember is that most mistakes can be undone, but if there's
165 anything you're not sure about feel free to bug the local CVS
166 meister (namely Jeff Lewis
167 <email>jlewis@galconn.com</email>). </para>
169 <sect2 id="cvs-access">
170 <title>Getting access to the CVS Repository</title>
172 <para>You can access the repository in one of two ways:
173 read-only (<xref linkend="cvs-read-only">), or read-write (<xref
174 linkend="cvs-read-write">).</para>
176 <sect3 id="cvs-read-only">
177 <title>Remote Read-only CVS Access</title>
179 <para>Read-only access is available to anyone - there's no
180 need to ask us first. With read-only CVS access you can do
181 anything except commit changes to the repository. You can
182 make changes to your local tree, and still use CVS's merge
183 facility to keep your tree up to date, and you can generate
184 patches using 'cvs diff' in order to send to us for
187 <para>To get read-only access to the repository:</para>
191 <para>Make sure that <application>cvs</application> is
192 installed on your machine.</para>
195 <para>Set your <literal>$CVSROOT</literal> environment variable to
196 <literal>:pserver:anoncvs@glass.cse.ogi.edu:/cvs</literal></para>
199 <para>Run the command</para>
203 <para>The password is simply <literal>cvs</literal>. This
204 sets up a file in your home directory called
205 <literal>.cvspass</literal>, which squirrels away the
206 dummy password, so you only need to do this step once.</para>
210 <para>Now go to <xref linkend="cvs-first">.</para>
215 <sect3 id="cvs-read-write">
216 <title>Remote Read-Write CVS Access</title>
218 <para>We generally supply read-write access to folk doing
219 serious development on some part of the source tree, when
220 going through us would be a pain. If you're developing some
221 feature, or think you have the time and inclination to fix
222 bugs in our sources, feel free to ask for read-write
223 access. There is a certain amount of responsibility that goes
224 with commit privileges; we are more likely to grant you access
225 if you've demonstrated your competence by sending us patches
226 via mail in the past.</para>
228 <para>To get remote read-write CVS access, you need to do the
229 following steps.</para>
233 <para>Make sure that <literal>cvs</literal> and
234 <literal>ssh</literal> are both installed on your
239 <para>Generate a DSA private-key/public-key pair, thus:</para>
243 <para>(<literal>ssh-keygen</literal> comes with
244 <literal>ssh</literal>.) Running <literal>ssh-keygen
245 -d</literal> creates the private and public keys in
246 <literal>$HOME/.ssh/id_dsa</literal> and
247 <literal>$HOME/.ssh/id_dsa.pub</literal> respectively
248 (assuming you accept the standard defaults).</para>
250 <para><literal>ssh-keygen -d</literal> will only work if
251 you have Version 2 <literal>ssh</literal> installed; it
252 will fail harmlessly otherwise. If you only have Version
253 1 you can instead generate an RSA key pair using plain</para>
258 <para>Doing so creates the private and public RSA keys in
259 <literal>$HOME/.ssh/identity</literal> and
260 <literal>$HOME/.ssh/identity.pub</literal>
263 <para>[Deprecated.] Incidentally, you can force a Version
264 2 <literal>ssh</literal> to use the Version 1 protocol by
265 creating <literal>$HOME/config</literal> with the
266 following in it:</para>
274 <para>In both cases, <literal>ssh-keygen</literal> will
275 ask for a <firstterm>passphrase</firstterm>. The
276 passphrase is a password that protects your private key.
277 In response to the 'Enter passphrase' question, you can
281 <para>[Recommended.] Enter a passphrase, which you
282 will quote each time you use CVS.
283 <literal>ssh-agent</literal> makes this entirely
287 <para>[Deprecated.] Just hit return (i.e. use an empty
288 passphrase); then you won't need to quote the
289 passphrase when using CVS. The downside is that
290 anyone who can see into your <literal>.ssh</literal>
291 directory, and thereby get your private key, can mess
292 up the repository. So you must keep the
293 <literal>.ssh</literal> directory with draconian
294 no-access permissions.</para>
298 <para>[Windows users. To protect your
299 <literal>.ssh</literal> from access by anyone else,
300 right-click your <literal>.ssh</literal> directory, and
301 select <literal>Properties</literal>. If you are not on
302 the access control list, add yourself, and give yourself
303 full permissions (the second panel). Remove everyone else
304 from the access control list. Don't leave them there but
305 deny them access, because 'they' may be a list that
306 includes you!]</para>
310 <para>Send a message to to the CVS repository
311 administrator (currently Jeff Lewis
312 <email>jeff@galconn.com</email>), containing:</para>
315 <para>Your desired user-name.</para>
318 <para>Your <literal>.ssh/id_dsa.pub</literal> (or
319 <literal>.ssh/identity.pub</literal>).</para>
322 <para>He will set up your account.</para>
326 <para>Set the following environment variables:</para>
329 <para><literal>$CVS_RSH</literal> to
330 <literal>ssh</literal></para>
333 <para><literal>$CVSROOT</literal> to
334 <literal>:ext:</literal><replaceable>your-username</replaceable><literal>@cvs.haskell.org:/home/cvs/root</literal></para>
341 <para>The <literal>CVSROOT</literal> environment variable will
342 be recorded in the checked-out tree, so you don't need to set
343 this every time either. Ignore the instructions for setting
344 <literal>CVSROOT</literal> below. </para>
346 <para>Caveats:</para>
350 <para>Setting your <literal>CVS_RSH</literal> to
351 <literal>ssh</literal> assumes that your CVS client
352 understands how to execute shell script
353 ("#!"s,really), which is what
354 <literal>ssh</literal> is. This may not be the case on
355 some platforms (read: Win32), so in that case set
356 <literal>CVS_RSH</literal> to
357 <literal>ssh1</literal>.</para>
361 <para>[Experts.] Once your account is set up, you can get
362 access from other machines without bothering Jeff, thus:</para>
365 <para>Generate a public/private key pair on the new
369 <para>Use ssh to log in to
370 <literal>cvs.haskell.org</literal>, from your old
374 <para>Add the public key for the new machine to the file
375 <literal>$HOME/ssh/authorized_keys</literal> on
376 <literal>cvs.haskell.org</literal>.
377 (<literal>authorized_keys2</literal>, I think, for Version
381 <para>Make sure that the new version of
382 <literal>authorized_keys</literal> still has 600 file
389 <sect2 id="cvs-first">
390 <title>Checking Out a Source Tree</title>
394 <para>Make sure you set your <literal>CVSROOT</literal>
395 environment variable according to either of the remote
396 methods above. The Approved Way to check out a source tree
397 is as follows:</para>
400 $ cvs checkout fpconfig
403 <para>At this point you have a new directory called
404 <literal>fptools</literal> which contains the basic stuff
405 for the fptools suite, including the configuration files and
406 some other junk. </para>
409 $ mv fptools <replaceable>directory</replaceable>
412 <para>You can call the fptools directory whatever you like,
413 CVS won't mind. </para>
415 <para> NB: after you've read the CVS manual you might be
416 tempted to try</para>
418 $ cvs checkout -d <replaceable>directory</replaceable> fpconfig
421 <para>instead of checking out <literal>fpconfig</literal>
422 and then renaming it. But this doesn't work, and will
423 result in checking out the entire repository instead of just
424 the <literal>fpconfig</literal> bit.</para>
426 $ cd <replaceable>directory</replaceable>
427 $ cvs checkout ghc hslibs
430 <para>The second command here checks out the relevant
431 modules you want to work on. For a GHC build, for instance,
432 you need at least the <literal>ghc</literal> and
433 <literal>hslibs</literal> modules (for a full list of the
434 projects available, see <xref linkend="projects">).</para>
439 <sect2 id="cvs-committing">
440 <title>Committing Changes</title>
442 <para>This is only if you have read-write access to the
443 repository. For anoncvs users, CVS will issue a "read-only
444 repository" error if you try to commit changes.</para>
448 <para>Build the software, if necessary. Unless you're just
449 working on documentation, you'll probably want to build the
450 software in order to test any changes you make.</para>
454 <para>Make changes. Preferably small ones first.</para>
458 <para>Test them. You can see exactly what changes you've
459 made by using the <literal>cvs diff</literal> command:</para>
463 <para>lists all the changes (using the
464 <literal>diff</literal> command) in and below the current
465 directory. In emacs, <literal>C-c C-v =</literal> runs
466 <literal>cvs diff</literal> on the current buffer and shows
467 you the results.</para>
471 <para>Before checking in a change, you need to update your
478 <para>This pulls in any changes that other people have made,
479 and merges them with yours. If there are any conflicts, CVS
480 will tell you, and you'll have to resolve them before you
481 can check your changes in. The documentation describes what
482 to do in the event of a conflict.</para>
484 <para>It's not always necessary to do a full cvs update
485 before checking in a change, since CVS will always tell you
486 if you try to check in a file that someone else has changed.
487 However, you should still update at regular intervals to
488 avoid making changes that don't work in conjuction with
489 changes that someone else made. Keeping an eye on what goes
490 by on the mailing list can help here.</para>
494 <para>When you're happy that your change isn't going to
495 break anything, check it in. For a one-file change:</para>
498 $ cvs commit <replaceable>filename</replaceable>
501 <para>CVS will then pop up an editor for you to enter a
502 "commit message", this is just a short description
503 of what your change does, and will be kept in the history of
506 <para>If you're using emacs, simply load up the file into a
507 buffer and type <literal>C-x C-q</literal>, and emacs will
508 prompt for a commit message and then check in the file for
511 <para>For a multiple-file change, things are a bit
512 trickier. There are several ways to do this, but this is the
513 way I find easiest. First type the commit message into a
514 temporary file. Then either</para>
517 $ cvs commit -F <replaceable>commit-message</replaceable> <replaceable>file_1</replaceable> .... <replaceable>file_n</replaceable>
520 <para>or, if nothing else has changed in this part of the
524 $ cvs commit -F <replaceable>commit-message</replaceable> <replaceable>directory</replaceable>
527 <para>where <replaceable>directory</replaceable> is a common
528 parent directory for all your changes, and
529 <replaceable>commit-message</replaceable> is the name of the
530 file containing the commit message.</para>
532 <para>Shortly afterwards, you'll get some mail from the
533 relevant mailing list saying which files changed, and giving
534 the commit message. For a multiple-file change, you should
535 still get only <emphasis>one</emphasis> message.</para>
540 <sect2 id="cvs-update">
541 <title>Updating Your Source Tree</title>
543 <para>It can be tempting to cvs update just part of a source
544 tree to bring in some changes that someone else has made, or
545 before committing your own changes. This is NOT RECOMMENDED!
546 Quite often changes in one part of the tree are dependent on
547 changes in another part of the tree (the
548 <literal>mk/*.mk</literal> files are a good example where
549 problems crop up quite often). Having an inconsistent tree is a
550 major cause of headaches. </para>
552 <para>So, to avoid a lot of hassle, follow this recipe for
553 updating your tree: </para>
557 $ cvs update -Pd 2>&1 | tee log</screen>
559 <para>Look at the log file, and fix any conflicts (denoted by a
560 <quote>C</quote> in the first column). If you're using multiple
561 build trees, then for every build tree you have pointing at this
562 source tree, you need to update the links in case any new files
563 have appeared: </para>
566 $ cd <replaceable>build-tree</replaceable>
567 $ lndir <replaceable>source-tree</replaceable>
570 <para>Some files might have been removed, so you need to remove
571 the links pointing to these non-existent files:</para>
574 $ find . -xtype l -exec rm '{}' \;
577 <para>To be <emphasis>really</emphasis> safe, you should do
580 <screen>$ gmake all</screen>
582 <para>from the top-level, to update the dependencies and build
583 any changed files. </para>
586 <sect2 id="cvs-tags">
587 <title>GHC Tag Policy</title>
589 <para>If you want to check out a particular version of GHC,
590 you'll need to know how we tag versions in the repository. The
591 policy (as of 4.04) is:</para>
595 <para>The tree is branched before every major release. The
596 branch tag is <literal>ghc-x-xx-branch</literal>, where
597 <literal>x-xx</literal> is the version number of the release
598 with the <literal>'.'</literal> replaced by a
599 <literal>'-'</literal>. For example, the 4.04 release lives
600 on <literal>ghc-4-04-branch</literal>.</para>
604 <para>The release itself is tagged with
605 <literal>ghc-x-xx</literal> (on the branch). eg. 4.06 is
606 called <literal>ghc-4-06</literal>.</para>
610 <para>We didn't always follow these guidelines, so to see
611 what tags there are for previous versions, do <literal>cvs
612 log</literal> on a file that's been around for a while (like
613 <literal>fptools/ghc/README</literal>).</para>
617 <para>So, to check out a fresh GHC 4.06 tree you would
621 $ cvs co -r ghc-4-06 fpconfig
623 $ cvs co -r ghc-4-06 ghc hslibs
627 <sect2 id="cvs-hints">
628 <title>General Hints</title>
632 <para>As a general rule: commit changes in small units,
633 preferably addressing one issue or implementing a single
634 feature. Provide a descriptive log message so that the
635 repository records exactly which changes were required to
636 implement a given feature/fix a bug. I've found this
637 <emphasis>very</emphasis> useful in the past for finding out
638 when a particular bug was introduced: you can just wind back
639 the CVS tree until the bug disappears.</para>
643 <para>Keep the sources at least *buildable* at any given
644 time. No doubt bugs will creep in, but it's quite easy to
645 ensure that any change made at least leaves the tree in a
646 buildable state. We do nightly builds of GHC to keep an eye
647 on what things work/don't work each day and how we're doing
648 in relation to previous verions. This idea is truely wrecked
649 if the compiler won't build in the first place!</para>
653 <para>To check out extra bits into an already-checked-out
654 tree, use the following procedure. Suppose you have a
655 checked-out fptools tree containing just ghc, and you want
656 to add nofib to it:</para>
667 $ cvs update -d nofib
670 <para>(the -d flag tells update to create a new
671 directory). If you just want part of the nofib suite, you
676 $ cvs checkout nofib/spectral
679 <para>This works because <literal>nofib</literal> is a
680 module in its own right, and spectral is a subdirectory of
681 the nofib module. The path argument to checkout must always
682 start with a module name. There's no equivalent form of this
683 command using <literal>update</literal>.</para>
689 <sect1 id="projects">
690 <title>What projects are there?</title>
692 <para>The <literal>fptools</literal> suite consists of several
693 <firstterm>projects</firstterm>, most of which can be downloaded,
694 built and installed individually. Each project corresponds to a
695 subdirectory in the source tree, and if checking out from CVS then
696 each project can be checked out individually by sitting in the top
697 level of your source tree and typing <command>cvs checkout
698 <replaceable>project</replaceable></command>.</para>
700 <para>Here is a list of the projects currently available:</para>
704 <term><literal>ghc</literal></term>
705 <indexterm><primary><literal>ghc</literal></primary>
706 <secondary>project</secondary></indexterm>
708 <para>The <ulink url="http://www.haskell.org/ghc/">Glasgow
709 Haskell Compiler</ulink> (minus libraries). Absolutely
710 required for building GHC.</para>
715 <term><literal>glafp-utils</literal></term>
716 <indexterm><primary><literal>glafp-utils</literal></primary><secondary>project</secondary></indexterm>
718 <para>Utility programs, some of which are used by the
719 build/installation system. Required for pretty much
725 <term><literal>green-card</literal></term>
726 <indexterm><primary><literal>green-card</literal></primary><secondary>project</secondary></indexterm>
729 url="http://www.haskell.org/greencard/">Green Card</ulink>
730 system for generating Haskell foreign function
736 <term><literal>haggis</literal></term>
737 <indexterm><primary><literal>haggis</literal></primary><secondary>project</secondary></indexterm>
740 url="http://www.dcs.gla.ac.uk/fp/software/haggis/">Haggis</ulink>
741 Haskell GUI framework.</para>
746 <term><literal>happy</literal></term>
747 <indexterm><primary><literal>happy</literal></primary><secondary>project</secondary></indexterm>
750 url="http://www.haskell.org/happy/">Happy</ulink> Parser
756 <term><literal>hdirect</literal></term>
757 <indexterm><primary><literal>hdirect</literal></primary><secondary>project</secondary></indexterm>
760 url="http://www.haskell.org/hdirect/">H/Direct</ulink>
761 Haskell interoperability tool.</para>
766 <term><literal>hood</literal></term>
767 <indexterm><primary><literal>hood</literal></primary><secondary>project</secondary></indexterm>
769 <para>The <ulink url="http://www.haskell.org/hood/">Haskell
770 Object Observation Debugger</ulink>.</para>
775 <term><literal>hslibs</literal></term>
776 <indexterm><primary><literal>hslibs</literal></primary><secondary>project</secondary></indexterm>
778 <para>GHC's libraries. Required for building GHC.</para>
783 <term><literal>libraries</literal></term>
784 <indexterm><primary><literal></literal></primary><secondary>project</secondary></indexterm>
786 <para>Hierarchical Haskell library suite
787 (experimental).</para>
792 <term><literal>mhms</literal></term>
793 <indexterm><primary><literal></literal></primary><secondary>project</secondary></indexterm>
795 <para>The Modular Haskell Metric System.</para>
800 <term><literal>nofib</literal></term>
801 <indexterm><primary><literal>nofib</literal></primary><secondary>project</secondary></indexterm>
803 <para>The NoFib suite: A collection of Haskell programs used
804 primarily for benchmarking.</para>
809 <term><literal>testsuite</literal></term>
810 <indexterm><primary><literal>testsuite</literal></primary><secondary>project</secondary></indexterm>
812 <para>A testing framework, including GHC's regression test
818 <para>So, to build GHC you need at least the
819 <literal>ghc</literal> and <literal>hslibs</literal> projects (a
820 GHC source distribution will already include the bits you
824 <sect1 id="sec-build-checks">
825 <title>Things to check before you start</title>
827 <para>Here's a list of things to check before you get
833 <indexterm><primary>Disk space needed</primary></indexterm>
834 <para>Disk space needed: from about 100Mb for a basic GHC
835 build, up to probably 500Mb for a GHC build with everything
836 included (libraries built several different ways,
841 <para>Use an appropriate machine, compilers, and things.
842 SPARC boxes, PCs running Linux or FreeBSD, and Alphas running
843 OSF/1 are all fully supported. Win32 and HP boxes are in
844 pretty good shape. PCs running Solaris, DEC Alphas running
845 Linux or some BSD variant, MIPS and AIX boxes will need some
846 minimal porting effort before they work (as of 4.06). <xref
847 linkend="sec-port-info"> gives the full run-down on ports or
852 <para>Be sure that the ``pre-supposed'' utilities are
853 installed. <Xref LinkEnd="sec-pre-supposed">
858 <para>If you have any problem when building or installing the
859 Glasgow tools, please check the ``known pitfalls'' (<Xref
860 LinkEnd="sec-build-pitfalls">). Also check the FAQ for the
861 version you're building, which should be available from the
862 relevant download page on the <ULink
863 URL="http://www.haskell.org/ghc/" >GHC web
866 <indexterm><primary>known bugs</primary></indexterm>
867 <indexterm><primary>bugs, known</primary></indexterm>
869 <para>If you feel there is still some shortcoming in our
870 procedure or instructions, please report it.</para>
872 <para>For GHC, please see the bug-reporting section of the GHC
873 Users' Guide (separate document), to maximise the usefulness
874 of your report.</para>
876 <indexterm><primary>bugs</primary><secondary>seporting</secondary></indexterm>
878 <para>If in doubt, please send a message to
879 <email>glasgow-haskell-bugs@haskell.org</email>.
880 <indexterm><primary>bugs</primary><secondary>mailing
881 list</secondary></indexterm></para>
887 <Sect1 id="sec-port-info">
888 <Title>What machines the Glasgow tools run on
892 <indexterm><primary>ports, GHC</primary></indexterm>
893 <indexterm><primary>GHC ports</primary></indexterm>
894 <indexterm><primary>supported platforms</primary></indexterm>
895 <indexterm><primary>platforms, supported</primary></indexterm>
896 The main question is whether or not the Haskell compiler (GHC) runs on
901 A ``platform'' is a architecture/manufacturer/operating-system
902 combination, such as <Literal>sparc-sun-solaris2</Literal>. Other common ones are
903 <Literal>alpha-dec-osf2</Literal>, <Literal>hppa1.1-hp-hpux9</Literal>, <Literal>i386-unknown-linux</Literal>,
904 <Literal>i386-unknown-solaris2</Literal>, <Literal>i386-unknown-freebsd</Literal>,
905 <Literal>i386-unknown-cygwin32</Literal>, <Literal>m68k-sun-sunos4</Literal>, <Literal>mips-sgi-irix5</Literal>,
906 <Literal>sparc-sun-sunos4</Literal>, <Literal>sparc-sun-solaris2</Literal>, <Literal>powerpc-ibm-aix</Literal>.
910 Bear in mind that certain ``bundles'', e.g. parallel Haskell, may not
911 work on all machines for which basic Haskell compiling is supported.
915 Some libraries may only work on a limited number of platforms; for
916 example, a sockets library is of no use unless the operating system
917 supports the underlying BSDisms.
921 <Title>What platforms the Haskell compiler (GHC) runs on</Title>
924 <indexterm><primary>fully-supported platforms</primary></indexterm>
925 <indexterm><primary>native-code generator</primary></indexterm>
926 <indexterm><primary>registerised ports</primary></indexterm>
927 <indexterm><primary>unregisterised ports</primary></indexterm>
928 The GHC hierarchy of Porting Goodness: (a) Best is a native-code
929 generator; (b) next best is a ``registerised''
930 port; (c) the bare minimum is an ``unregisterised'' port.
931 (``Unregisterised'' is so terrible that we won't say more about it).
935 We use Sparcs running Solaris 2.7 and x86 boxes running FreeBSD and
936 Linux, so those are the best supported platforms, unsurprisingly.
940 Here's everything that's known about GHC ports. We identify platforms
941 by their ``canonical'' CPU/Manufacturer/OS triple.
947 <term>alpha-dec-{osf,linux,freebsd,openbsd,netbsd}:</term>
948 <indexterm><primary>alpha-dec-osf</primary></indexterm>
949 <indexterm><primary>alpha-dec-linux</primary></indexterm>
950 <indexterm><primary>alpha-dec-freebsd</primary></indexterm>
951 <indexterm><primary>alpha-dec-openbsd</primary></indexterm>
952 <indexterm><primary>alpha-dec-netbsd</primary></indexterm>
955 <para>The OSF port is currently working (as of GHC version
956 5.02.1) and well supported. The native code generator is
957 currently non-working. Other operating systems will
958 require some minor porting.</para>
963 <term>sparc-sun-sunos4</term>
964 <indexterm><primary>sparc-sun-sunos4</primary></indexterm>
966 <para>Probably works with minor tweaks, hasn't been tested
972 <term>sparc-sun-solaris2</term>
973 <indexterm><primary>sparc-sun-solaris2</primary></indexterm>
975 <para>Fully supported, including native-code
981 <term>hppa1.1-hp-hpux (HP-PA boxes running HPUX 9.x)</term>
982 <indexterm><primary>hppa1.1-hp-hpux</primary></indexterm>
984 <para>Works registerised. No native-code
990 <term>i386-unknown-linux (PCs running Linux, ELF binary format)</term>
991 <indexterm><primary>i386-*-linux</primary></indexterm>
993 <para>GHC works registerised and has a native code
994 generator. You <Emphasis>must</Emphasis> have GCC 2.7.x
995 or later. NOTE about <literal>glibc</literal> versions:
996 GHC binaries built on a system running <literal>glibc
997 2.0</literal> won't work on a system running
998 <literal>glibc 2.1</literal>, and vice versa. In general,
999 don't expect compatibility between
1000 <literal>glibc</literal> versions, even if the shared
1001 library version hasn't changed.</para>
1006 <term>i386-unknown-freebsd (PCs running FreeBSD 2.2
1008 <indexterm><primary>i386-unknown-freebsd</primary></indexterm>
1010 <para>GHC works registerised. Pre-built packages are
1011 available in the native package format, so if you just
1012 need binaries you're better off just installing the
1018 <term>i386-unknown-{netbsd,openbsd) (PCs running NetBSD
1020 <indexterm><primary>i386-unknown-netbsd</primary></indexterm>
1021 <indexterm><primary>i386-unknown-openbsd</primary></indexterm>
1023 <para>Will require some minor porting effort, but should
1024 work registerised.</para>
1029 <term>i386-unknown-cygwin32:</term>
1030 <indexterm><primary>i386-unknown-cygwin32</primary></indexterm>
1032 <para>Fully supported under Win9x/NT, including a native
1033 code generator. Requires the <Literal>cygwin32</Literal>
1034 compatibility library and a healthy collection of GNU
1035 tools (i.e., gcc, GNU ld, bash etc.).</para>
1040 <term>mips-sgi-irix5</term>
1041 <indexterm><primary>mips-sgi-irix[5-6]</primary></indexterm>
1043 <para>Port currently doesn't work, needs some minimal
1044 porting effort. As usual, we don't have access to
1045 machines and there hasn't been an overwhelming demand for
1046 this port, but feel free to get in touch.</para>
1051 <term>powerpc-ibm-aix</term>
1052 <indexterm><primary>powerpc-ibm-aix</primary></indexterm>
1054 <para>Port currently doesn't work, needs some minimal
1055 porting effort. As usual, we don't have access to
1056 machines and there hasn't been an overwhelming demand for
1057 this port, but feel free to get in touch.</para>
1062 <term>powerpc-apple-darwin</term>
1063 <indexterm><primary>powerpc-apple-darwin</primary></indexterm>
1065 <para>Works, unregisterised only at the moment.</para>
1070 <para>Various other systems have had GHC ported to them in the
1071 distant past, including various Motorola 68k boxes. The 68k
1072 support still remains, but porting to one of these systems will
1073 certainly be a non-trivial task.</para>
1077 <title>What machines the other tools run on</title>
1079 <para>Unless you hear otherwise, the other tools work if GHC
1085 <Sect1 id="sec-pre-supposed">
1086 <Title>Installing pre-supposed utilities
1088 <indexterm><primary>pre-supposed utilities</primary></indexterm>
1089 <indexterm><primary>utilities, pre-supposed</primary></indexterm></Title>
1092 Here are the gory details about some utility programs you may need;
1093 <Command>perl</Command>, <Command>gcc</Command> and
1094 <command>happy</command> are the only important
1095 ones. (PVM<indexterm><primary>PVM</primary></indexterm> is important
1096 if you're going for Parallel Haskell.) The
1097 <Command>configure</Command><indexterm><primary>configure</primary></indexterm>
1098 script will tell you if you are missing something.
1106 <indexterm><primary>pre-supposed: Perl</primary></indexterm>
1107 <indexterm><primary>Perl, pre-supposed</primary></indexterm>
1110 <Emphasis>You have to have Perl to proceed!</Emphasis>
1111 It is pretty easy to install.
1115 Perl 5 is required. For Win32 platforms, you should use the binary
1116 supplied in the InstallShield (copy it to <filename>/bin</filename>).
1117 The Cygwin-supplied Perl seems not to work.
1121 Perl should be put somewhere so that it can be invoked by the
1122 <Literal>#!</Literal> script-invoking mechanism. The full
1123 pathname may need to be less than 32 characters long on some
1127 </listitem></VarListEntry>
1129 <term>GNU C (<Command>gcc</Command>):</term>
1130 <indexterm><primary>pre-supposed: GCC (GNU C compiler)</primary></indexterm>
1131 <indexterm><primary>GCC (GNU C compiler), pre-supposed</primary></indexterm>
1135 We recommend using GCC version 2.95.2 on all platforms. Failing that,
1136 version 2.7.2 is stable on most platforms. Earlier versions of GCC
1137 can be assumed not to work, and versions in between 2.7.2 and 2.95.2
1138 (including <command>egcs</command>) have varying degrees of stability
1139 depending on the platform.
1143 If your GCC dies with ``internal error'' on some GHC source file,
1144 please let us know, so we can report it and get things improved.
1145 (Exception: on iX86 boxes—you may need to fiddle with GHC's
1146 <Option>-monly-N-regs</Option> option; see the User's Guide)
1148 </listitem></VarListEntry>
1152 <indexterm><primary>Happy</primary></indexterm>
1154 <para>Happy is a parser generator tool for Haskell, and is used to
1155 generate GHC's parsers. Happy is written in Haskell, and is a project
1156 in the CVS repository (<literal>fptools/happy</literal>). It can be
1157 built from source, but bear in mind that you'll need GHC installed in
1158 order to build it. To avoid the chicken/egg problem, install a binary
1159 distribtion of either Happy or GHC to get started. Happy
1160 distributions are available from <ulink
1161 url="http://www.haskell.org/happy/">Happy's Web Page</ulink>.
1167 <term>Autoconf:</term>
1168 <indexterm><primary>pre-supposed: Autoconf</primary></indexterm>
1169 <indexterm><primary>Autoconf, pre-supposed</primary></indexterm>
1172 GNU Autoconf is needed if you intend to build from the CVS sources, it
1173 is <Emphasis>not</Emphasis> needed if you just intend to build a
1174 standard source distribution.
1178 Autoconf builds the <Command>configure</Command> script from
1179 <Filename>configure.in</Filename> and <Filename>aclocal.m4</Filename>.
1180 If you modify either of these files, you'll need
1181 <command>autoconf</command> to rebuild <Filename>configure</Filename>.
1184 </listitem></VarListEntry>
1186 <term><Command>sed</Command></term>
1187 <indexterm><primary>pre-supposed: sed</primary></indexterm>
1188 <indexterm><primary>sed, pre-supposed</primary></indexterm>
1191 You need a working <Command>sed</Command> if you are going to build
1192 from sources. The build-configuration stuff needs it. GNU sed
1193 version 2.0.4 is no good! It has a bug in it that is tickled by the
1194 build-configuration. 2.0.5 is OK. Others are probably OK too
1195 (assuming we don't create too elaborate configure scripts.)
1197 </listitem></VarListEntry>
1202 One <Literal>fptools</Literal> project is worth a quick note at this
1203 point, because it is useful for all the others:
1204 <Literal>glafp-utils</Literal> contains several utilities which aren't
1205 particularly Glasgow-ish, but Occasionally Indispensable. Like
1206 <Command>lndir</Command> for creating symbolic link trees.
1209 <Sect2 id="pre-supposed-gph-tools">
1210 <Title>Tools for building parallel GHC (GPH)
1217 <term>PVM version 3:</term>
1218 <indexterm><primary>pre-supposed: PVM3 (Parallel Virtual Machine)</primary></indexterm>
1219 <indexterm><primary>PVM3 (Parallel Virtual Machine), pre-supposed</primary></indexterm>
1223 PVM is the Parallel Virtual Machine on which Parallel Haskell programs
1224 run. (You only need this if you plan to run Parallel Haskell.
1225 Concurent Haskell, which runs concurrent threads on a uniprocessor
1226 doesn't need it.) Underneath PVM, you can have (for example) a
1227 network of workstations (slow) or a multiprocessor box (faster).
1231 The current version of PVM is 3.3.11; we use 3.3.7. It is readily
1232 available on the net; I think I got it from
1233 <Literal>research.att.com</Literal>, in <Filename>netlib</Filename>.
1237 A PVM installation is slightly quirky, but easy to do. Just follow
1238 the <Filename>Readme</Filename> instructions.
1240 </listitem></VarListEntry>
1242 <term><Command>bash</Command>:</term>
1243 <indexterm><primary>bash, presupposed (Parallel Haskell only)</primary></indexterm>
1246 Sadly, the <Command>gr2ps</Command> script, used to convert ``parallelism profiles''
1247 to PostScript, is written in Bash (GNU's Bourne Again shell).
1248 This bug will be fixed (someday).
1250 </listitem></VarListEntry>
1256 <Sect2 id="pre-supposed-doc-tools">
1257 <Title>Tools for building the Documentation
1261 The following additional tools are required if you want to format the
1262 documentation that comes with the <Literal>fptools</Literal> projects:
1269 <term>DocBook:</term>
1270 <indexterm><primary>pre-supposed: DocBook</primary></indexterm>
1271 <indexterm><primary>DocBook, pre-supposed</primary></indexterm>
1274 All our documentation is written in SGML, using the DocBook DTD.
1275 Instructions on installing and configuring the DocBook tools are in the
1276 installation guide (in the GHC user guide).
1279 </listitem></VarListEntry>
1282 <indexterm><primary>pre-supposed: TeX</primary></indexterm>
1283 <indexterm><primary>TeX, pre-supposed</primary></indexterm>
1286 A decent TeX distribution is required if you want to produce printable
1287 documentation. We recomment teTeX, which includes just about
1288 everything you need.
1290 </listitem></VarListEntry>
1295 In order to actually build any documentation, you need to set
1296 <constant>SGMLDocWays</constant> in your
1297 <filename>build.mk</filename>. Valid values to add to this
1298 list are: <literal>dvi</literal>, <literal>ps</literal>,
1299 <literal>pdf</literal>, <literal>html</literal>, and
1300 <literal>rtf</literal>.
1305 <Sect2 id="pre-supposed-other-tools">
1306 <Title>Other useful tools
1312 <indexterm><primary>pre-supposed: flex</primary></indexterm>
1313 <indexterm><primary>flex, pre-supposed</primary></indexterm>
1317 This is a quite-a-bit-better-than-Lex lexer. Used to build a couple
1318 of utilities in <Literal>glafp-utils</Literal>. Depending on your
1319 operating system, the supplied <Command>lex</Command> may or may not
1320 work; you should get the GNU version.
1322 </listitem></VarListEntry>
1329 <Sect1 id="sec-building-from-source">
1330 <Title>Building from source
1332 <indexterm><primary>Building from source</primary></indexterm>
1333 <indexterm><primary>Source, building from</primary></indexterm></Title>
1336 You've been rash enough to want to build some of
1337 the Glasgow Functional Programming tools (GHC, Happy,
1338 nofib, etc.) from source. You've slurped the source,
1339 from the CVS repository or from a source distribution, and
1340 now you're sitting looking at a huge mound of bits, wondering
1345 Gingerly, you type <Command>make</Command>. Wrong already!
1349 This rest of this guide is intended for duffers like me, who aren't
1350 really interested in Makefiles and systems configurations, but who
1351 need a mental model of the interlocking pieces so that they can make
1352 them work, extend them consistently when adding new software, and lay
1353 hands on them gently when they don't work.
1356 <Sect2 id="sec-source-tree">
1357 <Title>Your source tree
1361 The source code is held in your <Emphasis>source tree</Emphasis>.
1362 The root directory of your source tree <Emphasis>must</Emphasis>
1363 contain the following directories and files:
1372 <Filename>Makefile</Filename>: the root Makefile.
1378 <Filename>mk/</Filename>: the directory that contains the
1379 main Makefile code, shared by all the
1380 <Literal>fptools</Literal> software.
1386 <Filename>configure.in</Filename>, <Filename>config.sub</Filename>, <Filename>config.guess</Filename>:
1387 these files support the configuration process.
1393 <Filename>install-sh</Filename>.
1402 All the other directories are individual <Emphasis>projects</Emphasis> of the
1403 <Literal>fptools</Literal> system—for example, the Glasgow Haskell Compiler
1404 (<Literal>ghc</Literal>), the Happy parser generator (<Literal>happy</Literal>), the <Literal>nofib</Literal> benchmark
1405 suite, and so on. You can have zero or more of these. Needless to
1406 say, some of them are needed to build others.
1410 The important thing to remember is that even if you want only one
1411 project (<Literal>happy</Literal>, say), you must have a source tree whose root
1412 directory contains <Filename>Makefile</Filename>, <Filename>mk/</Filename>, <Filename>configure.in</Filename>, and the
1413 project(s) you want (<Filename>happy/</Filename> in this case). You cannot get by with
1414 just the <Filename>happy/</Filename> directory.
1421 <indexterm><primary>build trees</primary></indexterm>
1422 <indexterm><primary>link trees, for building</primary></indexterm></Title>
1425 While you can build a system in the source tree, we don't recommend it.
1426 We often want to build multiple versions of our software
1427 for different architectures, or with different options (e.g. profiling).
1428 It's very desirable to share a single copy of the source code among
1433 So for every source tree we have zero or more <Emphasis>build trees</Emphasis>. Each
1434 build tree is initially an exact copy of the source tree, except that
1435 each file is a symbolic link to the source file, rather than being a
1436 copy of the source file. There are ``standard'' Unix utilities that
1437 make such copies, so standard that they go by different names:
1438 <Command>lndir</Command><indexterm><primary>lndir</primary></indexterm>, <Command>mkshadowdir</Command><indexterm><primary>mkshadowdir</primary></indexterm> are two (If you
1439 don't have either, the source distribution includes sources for the
1440 X11 <Command>lndir</Command>—check out <Filename>fptools/glafp-utils/lndir</Filename>). See <Xref LinkEnd="sec-storysofar"> for a typical invocation.
1444 The build tree does not need to be anywhere near the source tree in
1445 the file system. Indeed, one advantage of separating the build tree
1446 from the source is that the build tree can be placed in a
1447 non-backed-up partition, saving your systems support people from
1448 backing up untold megabytes of easily-regenerated, and
1449 rapidly-changing, gubbins. The golden rule is that (with a single
1450 exception—<XRef LinkEnd="sec-build-config">)
1451 <Emphasis>absolutely everything in the build tree is either a symbolic
1452 link to the source tree, or else is mechanically generated</Emphasis>.
1453 It should be perfectly OK for your build tree to vanish overnight; an
1454 hour or two compiling and you're on the road again.
1458 You need to be a bit careful, though, that any new files you create
1459 (if you do any development work) are in the source tree, not a build tree!
1463 Remember, that the source files in the build tree are <Emphasis>symbolic
1464 links</Emphasis> to the files in the source tree. (The build tree soon
1465 accumulates lots of built files like <Filename>Foo.o</Filename>, as well.) You
1466 can <Emphasis>delete</Emphasis> a source file from the build tree without affecting
1467 the source tree (though it's an odd thing to do). On the other hand,
1468 if you <Emphasis>edit</Emphasis> a source file from the build tree, you'll edit the
1469 source-tree file directly. (You can set up Emacs so that if you edit
1470 a source file from the build tree, Emacs will silently create an
1471 edited copy of the source file in the build tree, leaving the source
1472 file unchanged; but the danger is that you think you've edited the
1473 source file whereas actually all you've done is edit the build-tree
1474 copy. More commonly you do want to edit the source file.)
1478 Like the source tree, the top level of your build tree must be (a
1479 linked copy of) the root directory of the <Literal>fptools</Literal> suite. Inside
1480 Makefiles, the root of your build tree is called
1481 <constant>$(FPTOOLS_TOP)</constant><indexterm><primary>FPTOOLS_TOP</primary></indexterm>. In the rest of this document path
1482 names are relative to <constant>$(FPTOOLS_TOP)</constant> unless otherwise stated. For
1483 example, the file <Filename>ghc/mk/target.mk</Filename> is actually
1484 <Filename><constant>$(FPTOOLS_TOP)</constant>/ghc/mk/target.mk</Filename>.
1489 <Sect2 id="sec-build-config">
1490 <Title>Getting the build you want
1494 When you build <Literal>fptools</Literal> you will be compiling code on a particular
1495 <Emphasis>host platform</Emphasis>, to run on a particular <Emphasis>target platform</Emphasis>
1496 (usually the same as the host platform)<indexterm><primary>platform</primary></indexterm>. The
1497 difficulty is that there are minor differences between different
1498 platforms; minor, but enough that the code needs to be a bit different
1499 for each. There are some big differences too: for a different
1500 architecture we need to build GHC with a different native-code
1505 There are also knobs you can turn to control how the <Literal>fptools</Literal>
1506 software is built. For example, you might want to build GHC optimised
1507 (so that it runs fast) or unoptimised (so that you can compile it fast
1508 after you've modified it. Or, you might want to compile it with
1509 debugging on (so that extra consistency-checking code gets included)
1514 All of this stuff is called the <Emphasis>configuration</Emphasis> of your build.
1515 You set the configuration using a three-step process.
1519 <term>Step 1: get ready for configuration.</term>
1521 <para>Change directory to
1522 <constant>$(FPTOOLS_TOP)</constant> and
1524 <Command>autoconf</Command><indexterm><primary>autoconf</primary></indexterm>
1525 (with no arguments). This GNU program converts
1526 <Filename><constant>$(FPTOOLS_TOP)</constant>/configure.in</Filename>
1527 to a shell script called
1528 <Filename><constant>$(FPTOOLS_TOP)</constant>/configure</Filename>.
1531 <para>Some projects, including GHC, have their own
1532 configure script. If there's an
1533 <constant>$(FPTOOLS_TOP)/<project>/configure.in</constant>,
1534 then you need to run <command>autoconf</command> in that
1535 directory too.</para>
1537 <para>Both these steps are completely
1538 platform-independent; they just mean that the
1539 human-written file (<Filename>configure.in</Filename>)
1540 can be short, although the resulting shell script,
1541 <Command>configure</Command>, and
1542 <Filename>mk/config.h.in</Filename>, are long.</para>
1544 <para>In case you don't have <Command>autoconf</Command>
1545 we distribute the results, <Command>configure</Command>,
1546 and <Filename>mk/config.h.in</Filename>, with the source
1547 distribution. They aren't kept in the repository,
1553 <term>Step 2: system configuration.</term>
1555 <para>Runs the newly-created
1556 <Command>configure</Command> script, thus:</para>
1559 ./configure <optional><parameter>args</parameter></optional>
1562 <para><Command>configure</Command>'s mission is to
1563 scurry round your computer working out what architecture
1564 it has, what operating system, whether it has the
1565 <Function>vfork</Function> system call, where
1566 <Command>yacc</Command> is kept, whether
1567 <Command>gcc</Command> is available, where various
1568 obscure <Literal>#include</Literal> files are,
1569 whether it's a leap year, and what the systems manager
1570 had for lunch. It communicates these snippets of
1571 information in two ways:</para>
1577 <Filename>mk/config.mk.in</Filename><indexterm><primary>config.mk.in</primary></indexterm>
1579 <Filename>mk/config.mk</Filename><indexterm><primary>config.mk</primary></indexterm>,
1580 substituting for things between
1581 ``<Literal>@</Literal>'' brackets. So,
1582 ``<Literal>@HaveGcc@</Literal>'' will be replaced by
1583 ``<Literal>YES</Literal>'' or
1584 ``<Literal>NO</Literal>'' depending on what
1585 <Command>configure</Command> finds.
1586 <Filename>mk/config.mk</Filename> is included by
1587 every Makefile (directly or indirectly), so the
1588 configuration information is thereby communicated to
1589 all Makefiles.</para>
1593 <para> It translates
1594 <Filename>mk/config.h.in</Filename><indexterm><primary>config.h.in</primary></indexterm>
1596 <Filename>mk/config.h</Filename><indexterm><primary>config.h</primary></indexterm>.
1597 The latter is <Literal>#include</Literal>d by
1598 various C programs, which can thereby make use of
1599 configuration information.</para>
1603 <para><command>configure</command> takes some optional
1604 arguments. Use <literal>./configure --help</literal> to
1605 get a list of the available arguments. Here are some of
1606 the ones you might need:</para>
1610 <term><literal>--with-ghc=<parameter>path</parameter></literal></term>
1611 <indexterm><primary><literal>--with-ghc</literal></primary>
1614 <para>Specifies the path to an installed GHC which
1615 you would like to use. This compiler will be used
1616 for compiling GHC-specific code (eg. GHC itself).
1617 This option <emphasis>cannot</emphasis> be
1618 specified using <filename>build.mk</filename> (see
1619 later), because <command>configure</command> needs
1620 to auto-detect the version of GHC you're using.
1621 The default is to look for a compiler named
1622 <literal>ghc</literal> in your path.</para>
1627 <term><literal>--with-hc=<parameter>path</parameter></literal></term>
1628 <indexterm><primary><literal>--with-hc</literal></primary>
1631 <para>Specifies the path to any installed Haskell
1632 compiler. This compiler will be used for
1633 compiling generic Haskell code. The default is to
1634 use <literal>ghc</literal>.</para>
1639 <term><literal>--with-gcc=<parameter>path</parameter></literal></term>
1640 <indexterm><primary><literal>--with-gcc</literal></primary>
1643 <para>Specifies the path to the installed
1644 GCC. This compiler will be used to compile all C
1645 files, <emphasis>except</emphasis> any generated
1646 by the installed Haskell compiler, which will have
1647 its own idea of which C compiler (if any) to use.
1648 The default is to use <literal>gcc</literal>.</para>
1653 <para><command>configure</command> caches the results of
1654 its run in <Filename>config.cache</Filename>. Quite
1655 often you don't want that; you're running
1656 <Command>configure</Command> a second time because
1657 something has changed. In that case, simply delete
1658 <Filename>config.cache</Filename>.</para>
1663 <term>Step 3: build configuration.</term>
1666 Next, you say how this build of <Literal>fptools</Literal> is to differ from the
1667 standard defaults by creating a new file <Filename>mk/build.mk</Filename><indexterm><primary>build.mk</primary></indexterm>
1668 <Emphasis>in the build tree</Emphasis>. This file is the one and only file you edit
1669 in the build tree, precisely because it says how this build differs
1670 from the source. (Just in case your build tree does die, you might
1671 want to keep a private directory of <Filename>build.mk</Filename> files, and use a
1672 symbolic link in each build tree to point to the appropriate one.) So
1673 <Filename>mk/build.mk</Filename> never exists in the source tree—you create one in
1674 each build tree from the template. We'll discuss what to put in it
1677 </listitem></VarListEntry>
1682 And that's it for configuration. Simple, eh?
1685 <para>What do you put in your build-specific configuration file
1686 <filename>mk/build.mk</filename>? <Emphasis>For almost all
1687 purposes all you will do is put make variable definitions that
1688 override those in</Emphasis>
1689 <filename>mk/config.mk.in</filename>. The whole point of
1690 <filename>mk/config.mk.in</filename>—and its derived
1691 counterpart <filename>mk/config.mk</filename>—is to define
1692 the build configuration. It is heavily commented, as you will
1693 see if you look at it. So generally, what you do is look at
1694 <filename>mk/config.mk.in</filename>, and add definitions in
1695 <filename>mk/build.mk</filename> that override any of the
1696 <filename>config.mk</filename> definitions that you want to
1697 change. (The override occurs because the main boilerplate file,
1698 <filename>mk/boilerplate.mk</filename><indexterm><primary>boilerplate.mk</primary></indexterm>,
1699 includes <filename>build.mk</filename> after
1700 <filename>config.mk</filename>.)</para>
1702 <para>For example, <filename>config.mk.in</filename> contains
1703 the definition:</para>
1706 GhcHcOpts=-O -Rghc-timing
1709 <para>The accompanying comment explains that this is the list of
1710 flags passed to GHC when building GHC itself. For doing
1711 development, it is wise to add <literal>-DDEBUG</literal>, to
1712 enable debugging code. So you would add the following to
1713 <filename>build.mk</filename>:</para>
1715 <para>or, if you prefer,</para>
1718 GhcHcOpts += -DDEBUG
1721 <para>GNU <Command>make</Command> allows existing definitions to
1722 have new text appended using the ``<Literal>+=</Literal>''
1723 operator, which is quite a convenient feature.)</para>
1725 <para>If you want to remove the <literal>-O</literal> as well (a
1726 good idea when developing, because the turn-around cycle gets a
1727 lot quicker), you can just override
1728 <literal>GhcLibHcOpts</literal> altogether:</para>
1731 GhcHcOpts=-DDEBUG -Rghc-timing
1734 <para>When reading <filename>config.mk.in</filename>, remember
1735 that anything between ``@...@'' signs is going to be substituted
1736 by <Command>configure</Command> later. You
1737 <Emphasis>can</Emphasis> override the resulting definition if
1738 you want, but you need to be a bit surer what you are doing.
1739 For example, there's a line that says:</para>
1745 <para>This defines the Make variables <constant>YACC</constant>
1746 to the pathname for a <Command>yacc</Command> that
1747 <Command>configure</Command> finds somewhere. If you have your
1748 own pet <Command>yacc</Command> you want to use instead, that's
1749 fine. Just add this line to <filename>mk/build.mk</filename>:</para>
1755 <para>You do not <Emphasis>have</Emphasis> to have a
1756 <filename>mk/build.mk</filename> file at all; if you don't,
1757 you'll get all the default settings from
1758 <filename>mk/config.mk.in</filename>.</para>
1760 <para>You can also use <filename>build.mk</filename> to override
1761 anything that <Command>configure</Command> got wrong. One place
1762 where this happens often is with the definition of
1763 <constant>FPTOOLS_TOP_ABS</constant>: this
1764 variable is supposed to be the canonical path to the top of your
1765 source tree, but if your system uses an automounter then the
1766 correct directory is hard to find automatically. If you find
1767 that <Command>configure</Command> has got it wrong, just put the
1768 correct definition in <filename>build.mk</filename>.</para>
1772 <sect2 id="sec-storysofar">
1773 <title>The story so far</title>
1775 <para>Let's summarise the steps you need to carry to get
1776 yourself a fully-configured build tree from scratch.</para>
1780 <para> Get your source tree from somewhere (CVS repository
1781 or source distribution). Say you call the root directory
1782 <filename>myfptools</filename> (it does not have to be
1783 called <filename>fptools</filename>). Make sure that you
1784 have the essential files (see <XRef
1785 LinkEnd="sec-source-tree">).</para>
1790 <para>(Optional) Use <Command>lndir</Command> or
1791 <Command>mkshadowdir</Command> to create a build tree.</para>
1795 $ mkshadowdir . /scratch/joe-bloggs/myfptools-sun4
1798 <para>(N.B. <Command>mkshadowdir</Command>'s first argument
1799 is taken relative to its second.) You probably want to give
1800 the build tree a name that suggests its main defining
1801 characteristic (in your mind at least), in case you later
1806 <para>Change directory to the build tree. Everything is
1807 going to happen there now.</para>
1810 $ cd /scratch/joe-bloggs/myfptools-sun4
1816 <para>Prepare for system configuration:</para>
1822 <para>(You can skip this step if you are starting from a
1823 source distribution, and you already have
1824 <filename>configure</filename> and
1825 <filename>mk/config.h.in</filename>.)</para>
1827 <para>Some projects, including GHC itself, have their own
1828 configure scripts, so it is necessary to run autoconf again
1829 in the appropriate subdirectories. eg:</para>
1832 $ (cd ghc; autoconf)
1837 <para>Do system configuration:</para>
1843 <para>Don't forget to check whether you need to add any
1844 arguments to <literal>configure</literal>; for example, a
1845 common requirement is to specify which GHC to use with
1846 <option>--with-ghc=<replaceable>ghc</replaceable></option>.</para>
1850 <para>Create the file <filename>mk/build.mk</filename>,
1851 adding definitions for your desired configuration
1860 <para>You can make subsequent changes to
1861 <filename>mk/build.mk</filename> as often as you like. You do
1862 not have to run any further configuration programs to make these
1863 changes take effect. In theory you should, however, say
1864 <Command>gmake clean</Command>, <Command>gmake all</Command>,
1865 because configuration option changes could affect
1866 anything—but in practice you are likely to know what's
1871 <Title>Making things</Title>
1873 <para>At this point you have made yourself a fully-configured
1874 build tree, so you are ready to start building real
1877 <para>The first thing you need to know is that <Emphasis>you
1878 must use GNU <Command>make</Command>, usually called
1879 <Command>gmake</Command>, not standard Unix
1880 <Command>make</Command></Emphasis>. If you use standard Unix
1881 <Command>make</Command> you will get all sorts of error messages
1882 (but no damage) because the <Literal>fptools</Literal>
1883 <Command>Makefiles</Command> use GNU <Command>make</Command>'s
1884 facilities extensively.</para>
1886 <para>To just build the whole thing, <command>cd</command> to
1887 the top of your <literal>fptools</literal> tree and type
1888 <command>gmake</command>. This will prepare the tree and build
1889 the various projects in the correct order.</para>
1893 <Sect2 id="sec-standard-targets">
1894 <Title>Standard Targets</title>
1895 <indexterm><primary>targets, standard makefile</primary></indexterm>
1896 <indexterm><primary>makefile targets</primary></indexterm>
1898 <para>In any directory you should be able to make the following:
1903 <term><Literal>boot</Literal>:</term>
1905 <para>does the one-off preparation required to get ready for the real
1906 work. Notably, it does <Command>gmake depend</Command> in all
1907 directories that contain programs. It also builds the necessary tools
1908 for compilation to proceed.</para>
1910 <para>Invoking the <literal>boot</literal> target explicitly is not
1911 normally necessary. From the top-level <literal>fptools</literal>
1912 directory, invoking <literal>gmake</literal> causes <literal>gmake
1913 boot all</literal> to be invoked in each of the project
1914 subdirectories, in the order specified by
1915 <literal>$(AllTargets)</literal> in
1916 <literal>config.mk</literal>.</para>
1918 <para>If you're working in a subdirectory somewhere and need to update
1919 the dependencies, <literal>gmake boot</literal> is a good way to do it.</para>
1921 </listitem></VarListEntry>
1923 <term><Literal>all</Literal>:</term>
1926 makes all the final target(s) for this Makefile.
1927 Depending on which directory you are in a ``final target'' may be an
1928 executable program, a library archive, a shell script, or a Postscript
1929 file. Typing <Command>gmake</Command> alone is generally the same as typing <Command>gmake all</Command>.
1931 </listitem></VarListEntry>
1933 <term><Literal>install</Literal>:</term>
1936 installs the things built by <Literal>all</Literal> (except for the documentation). Where does it
1937 install them? That is specified by
1938 <filename>mk/config.mk.in</filename>; you can override it in
1939 <filename>mk/build.mk</filename>, or by running
1940 <command>configure</command> with command-line arguments like
1941 <literal>--bindir=/home/simonpj/bin</literal>; see <literal>./configure
1942 --help</literal> for the full details.
1944 </listitem></VarListEntry>
1946 <term><Literal>install-docs</Literal>:</term>
1949 installs the documentation. Otherwise behaves just like <literal>install</literal>.
1951 </listitem></VarListEntry>
1953 <term><Literal>uninstall</Literal>:</term>
1956 reverses the effect of <Literal>install</Literal>.
1958 </listitem></VarListEntry>
1961 <term><Literal>clean</Literal>:</term>
1964 Delete all files from the current directory that are normally created
1965 by building the program. Don't delete the files that record the
1966 configuration, or files generated by <Command>gmake boot</Command>.
1967 Also preserve files that could be made by building, but normally
1968 aren't because the distribution comes with them.</para>
1969 </listitem></VarListEntry>
1972 <term><literal>distclean</literal>:</term>
1974 <para>Delete all files from the current directory that are created by
1975 configuring or building the program. If you have unpacked the source
1976 and built the program without creating any other files, <literal>make
1977 distclean</literal> should leave only the files that were in the
1978 distribution.</para>
1983 <term><literal>mostlyclean</literal>:</term>
1985 <para>Like <literal>clean</literal>, but may refrain from deleting a
1986 few files that people normally don't want to recompile.</para>
1991 <term><Literal>maintainer-clean</Literal>:</term>
1994 Delete everything from the current directory that can be reconstructed
1995 with this Makefile. This typically includes everything deleted by
1996 <literal>distclean</literal>, plus more: C source files produced by
1997 Bison, tags tables, Info files, and so on.</para>
1999 <para>One exception, however: <literal>make maintainer-clean</literal>
2000 should not delete <filename>configure</filename> even if
2001 <filename>configure</filename> can be remade using a rule in the
2002 <filename>Makefile</filename>. More generally, <literal>make
2003 maintainer-clean</literal> should not delete anything that needs to
2004 exist in order to run <filename>configure</filename> and then begin to
2005 build the program.</para>
2010 <term><Literal>check</Literal>:</term>
2015 </listitem></VarListEntry>
2020 All of these standard targets automatically recurse into
2021 sub-directories. Certain other standard targets do not:
2028 <term><Literal>configure</Literal>:</term>
2031 is only available in the root directory
2032 <constant>$(FPTOOLS_TOP)</constant>; it has been discussed in <XRef LinkEnd="sec-build-config">.
2034 </listitem></VarListEntry>
2036 <term><Literal>depend</Literal>:</term>
2039 make a <filename>.depend</filename> file in each directory that needs
2040 it. This <filename>.depend</filename> file contains mechanically-generated dependency
2041 information; for example, suppose a directory contains a Haskell
2042 source module <filename>Foo.lhs</filename> which imports another module <Literal>Baz</Literal>.
2043 Then the generated <filename>.depend</filename> file will contain the dependency:
2055 which says that the object file <filename>Foo.o</filename> depends on the interface file
2056 <filename>Baz.hi</filename> generated by compiling module <Literal>Baz</Literal>. The <filename>.depend</filename> file is
2057 automatically included by every Makefile.
2059 </listitem></VarListEntry>
2061 <term><Literal>binary-dist</Literal>:</term>
2064 make a binary distribution. This is the
2065 target we use to build the binary distributions of GHC and Happy.
2067 </listitem></VarListEntry>
2069 <term><Literal>dist</Literal>:</term>
2072 make a source distribution. Note that this target does “make
2073 distclean” as part of its work; don't use it if you want to keep
2076 </listitem></VarListEntry>
2081 Most <filename>Makefile</filename>s have targets other than these. You can discover them by looking in the <filename>Makefile</filename> itself.
2087 <title>Using a project from the build tree</title>
2089 If you want to build GHC (say) and just use it direct from the build
2090 tree without doing <literal>make install</literal> first, you can run
2091 the in-place driver script:
2092 <filename>ghc/compiler/ghc-inplace</filename>.
2095 <para> Do <emphasis>NOT</emphasis> use
2096 <filename>ghc/compiler/ghc</filename>, or
2097 <filename>ghc/compiler/ghc-5.xx</filename>, as these are the scripts
2098 intended for installation, and contain hard-wired paths to the
2099 installed libraries, rather than the libraries in the build tree.
2103 Happy can similarly be run from the build tree, using
2104 <filename>happy/src/happy-inplace</filename>.
2109 <Title>Fast Making <indexterm><primary>fastmake</primary></indexterm>
2110 <indexterm><primary>dependencies, omitting</primary></indexterm>
2111 <indexterm><primary>FAST, makefile
2112 variable</primary></indexterm></Title>
2115 Sometimes the dependencies get in the way: if you've made a small
2116 change to one file, and you're absolutely sure that it won't affect
2117 anything else, but you know that <Command>make</Command> is going to rebuild everything
2118 anyway, the following hack may be useful:
2130 This tells the make system to ignore dependencies and just build what
2131 you tell it to. In other words, it's equivalent to temporarily
2132 removing the <filename>.depend</filename> file in the current directory (where
2133 <Command>mkdependHS</Command> and friends store their dependency information).
2137 A bit of history: GHC used to come with a <Command>fastmake</Command> script that did
2138 the above job, but GNU make provides the features we need to do it
2139 without resorting to a script. Also, we've found that fastmaking is
2140 less useful since the advent of GHC's recompilation checker (see the
2141 User's Guide section on "Separate Compilation").
2148 <Sect1 id="sec-makefile-arch">
2149 <Title>The <filename>Makefile</filename> architecture
2150 <indexterm><primary>makefile architecture</primary></indexterm></Title>
2153 <Command>make</Command> is great if everything works—you type <Command>gmake install</Command> and
2154 lo! the right things get compiled and installed in the right places.
2155 Our goal is to make this happen often, but somehow it often doesn't;
2156 instead some weird error message eventually emerges from the bowels of
2157 a directory you didn't know existed.
2161 The purpose of this section is to give you a road-map to help you figure
2162 out what is going right and what is going wrong.
2166 <title>Debugging</title>
2168 <para>Debugging <filename>Makefile</filename>s is something of a
2169 black art, but here's a couple of tricks that we find
2170 particularly useful. The following command allows you to see
2171 the contents of any make variable in the context of the current
2172 <filename>Makefile</filename>:</para>
2174 <screen>$ make show VALUE=HS_SRCS</screen>
2176 <para>where you can replace <literal>HS_SRCS</literal> with the
2177 name of any variable you wish to see the value of.</para>
2179 <para>GNU make has a <option>-d</option> option which generates
2180 a dump of the decision procedure used to arrive at a conclusion
2181 about which files should be recompiled. Sometimes useful for
2182 tracking down problems with superfluous or missing
2183 recompilations.</para>
2187 <Title>A small project</Title>
2190 To get started, let us look at the <filename>Makefile</filename> for an imaginary small
2191 <Literal>fptools</Literal> project, <Literal>small</Literal>. Each project in <Literal>fptools</Literal> has its own
2192 directory in <constant>FPTOOLS_TOP</constant>, so the <Literal>small</Literal> project will have its own
2193 directory <constant>FPOOLS_TOP/small/</constant>. Inside the <filename>small/</filename> directory there
2194 will be a <filename>Makefile</filename>, looking something like this:
2198 <indexterm><primary>Makefile, minimal</primary></indexterm>
2201 # Makefile for fptools project "small"
2204 include $(TOP)/mk/boilerplate.mk
2206 SRCS = $(wildcard *.lhs) $(wildcard *.c)
2209 include $(TOP)/target.mk
2215 This <filename>Makefile</filename> has three sections:
2224 The first section includes
2228 One of the most important
2229 features of GNU <Command>make</Command> that we use is the ability for a <filename>Makefile</filename> to
2230 include another named file, very like <Command>cpp</Command>'s <Literal>#include</Literal>
2235 a file of ``boilerplate'' code from the level
2236 above (which in this case will be
2237 <filename><constant>FPTOOLS_TOP</constant>/mk/boilerplate.mk</filename><indexterm><primary>boilerplate.mk</primary></indexterm>). As its name
2238 suggests, <filename>boilerplate.mk</filename> consists of a large quantity of standard
2239 <filename>Makefile</filename> code. We discuss this boilerplate in more detail in
2240 <XRef LinkEnd="sec-boiler">.
2241 <indexterm><primary>include, directive in Makefiles</primary></indexterm>
2242 <indexterm><primary>Makefile inclusion</primary></indexterm>
2244 Before the <Literal>include</Literal> statement, you must define the <Command>make</Command> variable
2245 <constant>TOP</constant><indexterm><primary>TOP</primary></indexterm> to be the directory containing the <filename>mk</filename> directory in
2246 which the <filename>boilerplate.mk</filename> file is. It is <Emphasis>not</Emphasis> OK to simply say
2250 include ../mk/boilerplate.mk # NO NO NO
2254 Why? Because the <filename>boilerplate.mk</filename> file needs to know where it is, so
2255 that it can, in turn, <Literal>include</Literal> other files. (Unfortunately, when an
2256 <Literal>include</Literal>d file does an <Literal>include</Literal>, the filename is treated relative to
2257 the directory in which <Command>gmake</Command> is being run, not the directory in
2258 which the <Literal>include</Literal>d sits.) In general, <Emphasis>every file <filename>foo.mk</filename>
2259 assumes that <filename><constant>$(TOP)</constant>/mk/foo.mk</filename> refers to itself.</Emphasis> It is up to the
2260 <filename>Makefile</filename> doing the <Literal>include</Literal> to ensure this is the case.
2262 Files intended for inclusion in other <filename>Makefile</filename>s are written to have
2263 the following property: <Emphasis>after <filename>foo.mk</filename> is <Literal>include</Literal>d, it leaves
2264 <constant>TOP</constant> containing the same value as it had just before the <Literal>include</Literal>
2265 statement</Emphasis>. In our example, this invariant guarantees that the
2266 <Literal>include</Literal> for <filename>target.mk</filename> will look in the same directory as that for
2267 <filename>boilerplate.mk</filename>.
2274 The second section defines the following standard <Command>make</Command>
2275 variables: <constant>SRCS</constant><indexterm><primary>SRCS</primary></indexterm> (the source files from which is to be
2276 built), and <constant>HS_PROG</constant><indexterm><primary>HS_PROG</primary></indexterm> (the executable binary to be
2277 built). We will discuss in more detail what the ``standard
2278 variables'' are, and how they affect what happens, in <XRef LinkEnd="sec-targets">.
2280 The definition for <constant>SRCS</constant> uses the useful GNU <Command>make</Command> construct
2281 <Literal>$(wildcard $pat$)</Literal><indexterm><primary>wildcard</primary></indexterm>, which expands to a list of all
2282 the files matching the pattern <Literal>pat</Literal> in the current directory. In
2283 this example, <constant>SRCS</constant> is set to the list of all the <filename>.lhs</filename> and <filename>.c</filename>
2284 files in the directory. (Let's suppose there is one of each,
2285 <filename>Foo.lhs</filename> and <filename>Baz.c</filename>.)
2292 The last section includes a second file of standard code,
2293 called <filename>target.mk</filename><indexterm><primary>target.mk</primary></indexterm>. It contains the rules that tell
2294 <Command>gmake</Command> how to make the standard targets (<Xref LinkEnd="sec-standard-targets">). Why, you ask,
2295 can't this standard code be part of <filename>boilerplate.mk</filename>? Good question.
2296 We discuss the reason later, in <Xref LinkEnd="sec-boiler-arch">.
2298 You do not <Emphasis>have</Emphasis> to <Literal>include</Literal> the <filename>target.mk</filename> file. Instead, you
2299 can write rules of your own for all the standard targets. Usually,
2300 though, you will find quite a big payoff from using the canned rules
2301 in <filename>target.mk</filename>; the price tag is that you have to understand what
2302 canned rules get enabled, and what they do (<Xref LinkEnd="sec-targets">).
2312 In our example <filename>Makefile</filename>, most of the work is done by the two
2313 <Literal>include</Literal>d files. When you say <Command>gmake all</Command>, the following things
2323 <Command>gmake</Command> figures out that the object files are <filename>Foo.o</filename> and
2324 <filename>Baz.o</filename>.
2331 It uses a boilerplate pattern rule to compile <filename>Foo.lhs</filename> to
2332 <filename>Foo.o</filename> using a Haskell compiler. (Which one? That is set in the
2333 build configuration.)
2340 It uses another standard pattern rule to compile <filename>Baz.c</filename> to
2341 <filename>Baz.o</filename>, using a C compiler. (Ditto.)
2348 It links the resulting <filename>.o</filename> files together to make <Literal>small</Literal>,
2349 using the Haskell compiler to do the link step. (Why not use <Command>ld</Command>?
2350 Because the Haskell compiler knows what standard libraries to link in.
2351 How did <Command>gmake</Command> know to use the Haskell compiler to do the link,
2352 rather than the C compiler? Because we set the variable <constant>HS_PROG</constant>
2353 rather than <constant>C_PROG</constant>.)
2363 All <filename>Makefile</filename>s should follow the above three-section format.
2369 <Title>A larger project</Title>
2372 Larger projects are usually structured into a number of sub-directories,
2373 each of which has its own <filename>Makefile</filename>. (In very large projects, this
2374 sub-structure might be iterated recursively, though that is rare.)
2375 To give you the idea, here's part of the directory structure for
2376 the (rather large) GHC project:
2389 ...source files for documentation...
2392 ...source files for driver...
2395 parser/...source files for parser...
2396 renamer/...source files for renamer...
2403 The sub-directories <filename>docs</filename>, <filename>driver</filename>, <filename>compiler</filename>, and so on, each
2404 contains a sub-component of GHC, and each has its own <filename>Makefile</filename>.
2405 There must also be a <filename>Makefile</filename> in <filename><constant>$(FPTOOLS_TOP)</constant>/ghc</filename>. It does most
2406 of its work by recursively invoking <Command>gmake</Command> on the <filename>Makefile</filename>s in the
2407 sub-directories. We say that <filename>ghc/Makefile</filename> is a <Emphasis>non-leaf
2408 <filename>Makefile</filename></Emphasis>, because it does little except organise its children,
2409 while the <filename>Makefile</filename>s in the sub-directories are all <Emphasis>leaf
2410 <filename>Makefile</filename>s</Emphasis>. (In principle the sub-directories might themselves
2411 contain a non-leaf <filename>Makefile</filename> and several sub-sub-directories, but
2412 that does not happen in GHC.)
2416 The <filename>Makefile</filename> in <filename>ghc/compiler</filename> is considered a leaf <filename>Makefile</filename> even
2417 though the <filename>ghc/compiler</filename> has sub-directories, because these sub-directories
2418 do not themselves have <filename>Makefile</filename>s in them. They are just used to structure
2419 the collection of modules that make up GHC, but all are managed by the
2420 single <filename>Makefile</filename> in <filename>ghc/compiler</filename>.
2424 You will notice that <filename>ghc/</filename> also contains a directory <filename>ghc/mk/</filename>. It
2425 contains GHC-specific <filename>Makefile</filename> boilerplate code. More precisely:
2434 <filename>ghc/mk/boilerplate.mk</filename> is included at the top of
2435 <filename>ghc/Makefile</filename>, and of all the leaf <filename>Makefile</filename>s in the
2436 sub-directories. It in turn <Literal>include</Literal>s the main boilerplate file
2437 <filename>mk/boilerplate.mk</filename>.
2445 <filename>ghc/mk/target.mk</filename> is <Literal>include</Literal>d at the bottom of
2446 <filename>ghc/Makefile</filename>, and of all the leaf <filename>Makefile</filename>s in the
2447 sub-directories. It in turn <Literal>include</Literal>s the file <filename>mk/target.mk</filename>.
2457 So these two files are the place to look for GHC-wide customisation
2458 of the standard boilerplate.
2463 <Sect2 id="sec-boiler-arch">
2464 <Title>Boilerplate architecture
2465 <indexterm><primary>boilerplate architecture</primary></indexterm>
2469 Every <filename>Makefile</filename> includes a <filename>boilerplate.mk</filename><indexterm><primary>boilerplate.mk</primary></indexterm> file
2470 at the top, and <filename>target.mk</filename><indexterm><primary>target.mk</primary></indexterm> file at the bottom. In
2471 this section we discuss what is in these files, and why there have to
2472 be two of them. In general:
2481 <filename>boilerplate.mk</filename> consists of:
2487 <Emphasis>Definitions of millions of <Command>make</Command> variables</Emphasis> that
2488 collectively specify the build configuration. Examples:
2489 <constant>HC_OPTS</constant><indexterm><primary>HC_OPTS</primary></indexterm>, the options to feed to the Haskell compiler;
2490 <constant>NoFibSubDirs</constant><indexterm><primary>NoFibSubDirs</primary></indexterm>, the sub-directories to enable within the
2491 <Literal>nofib</Literal> project; <constant>GhcWithHc</constant><indexterm><primary>GhcWithHc</primary></indexterm>, the name of the Haskell
2492 compiler to use when compiling GHC in the <Literal>ghc</Literal> project.
2498 <Emphasis>Standard pattern rules</Emphasis> that tell <Command>gmake</Command> how to construct one
2506 <filename>boilerplate.mk</filename> needs to be <Literal>include</Literal>d at the <Emphasis>top</Emphasis>
2507 of each <filename>Makefile</filename>, so that the user can replace the
2508 boilerplate definitions or pattern rules by simply giving a new
2509 definition or pattern rule in the <filename>Makefile</filename>. <Command>gmake</Command>
2510 simply takes the last definition as the definitive one.
2512 Instead of <Emphasis>replacing</Emphasis> boilerplate definitions, it is also quite
2513 common to <Emphasis>augment</Emphasis> them. For example, a <filename>Makefile</filename> might say:
2521 thereby adding ``<Option>-O</Option>'' to the end of <constant>SRC_HC_OPTS</constant><indexterm><primary>SRC_HC_OPTS</primary></indexterm>.
2528 <filename>target.mk</filename> contains <Command>make</Command> rules for the standard
2529 targets described in <Xref LinkEnd="sec-standard-targets">. These rules are selectively included,
2530 depending on the setting of certain <Command>make</Command> variables. These
2531 variables are usually set in the middle section of the
2532 <filename>Makefile</filename> between the two <Literal>include</Literal>s.
2534 <filename>target.mk</filename> must be included at the end (rather than being part of
2535 <filename>boilerplate.mk</filename>) for several tiresome reasons:
2542 <Command>gmake</Command> commits target and dependency lists earlier than
2543 it should. For example, <FIlename>target.mk</FIlename> has a rule that looks like
2548 $(HS_PROG) : $(OBJS)
2549 $(HC) $(LD_OPTS) $< -o $@
2553 If this rule was in <filename>boilerplate.mk</filename> then <constant>$(HS_PROG)</constant><indexterm><primary>HS_PROG</primary></indexterm>
2554 and <constant>$(OBJS)</constant><indexterm><primary>OBJS</primary></indexterm> would not have their final values at the
2555 moment <Command>gmake</Command> encountered the rule. Alas, <Command>gmake</Command> takes a snapshot
2556 of their current values, and wires that snapshot into the rule. (In
2557 contrast, the commands executed when the rule ``fires'' are only
2558 substituted at the moment of firing.) So, the rule must follow the
2559 definitions given in the <filename>Makefile</filename> itself.
2566 Unlike pattern rules, ordinary rules cannot be overriden or
2567 replaced by subsequent rules for the same target (at least, not without an
2568 error message). Including ordinary rules in <filename>boilerplate.mk</filename> would
2569 prevent the user from writing rules for specific targets in specific cases.
2576 There are a couple of other reasons I've forgotten, but it doesn't
2592 <Sect2 id="sec-boiler">
2593 <Title>The main <filename>mk/boilerplate.mk</filename> file
2595 <indexterm><primary>boilerplate.mk</primary></indexterm></Title>
2598 If you look at <filename><constant>$(FPTOOLS_TOP)</constant>/mk/boilerplate.mk</filename> you will find
2599 that it consists of the following sections, each held in a separate
2606 <term><filename>config.mk</filename></term>
2607 <indexterm><primary>config.mk</primary></indexterm>
2609 <para>is the build configuration file we discussed at
2610 length in <Xref LinkEnd="sec-build-config">.</para>
2615 <term><filename>paths.mk</filename></term>
2616 <indexterm><primary>paths.mk</primary></indexterm>
2618 <para>defines <Command>make</Command> variables for
2619 pathnames and file lists. This file contains code for
2620 automatically compiling lists of source files and deriving
2621 lists of object files from those. The results can be
2622 overriden in the <filename>Makefile</filename>, but in
2623 most cases the automatic setup should do the right
2626 <para>The following variables may be set in the
2627 <filename>Makefile</filename> to affect how the automatic
2628 source file search is done:</para>
2632 <term><literal>ALL_DIRS</literal></term>
2633 <indexterm><primary><literal>ALL_DIRS</literal></primary>
2636 <para>Set to a list of directories to search in
2637 addition to the current directory for source
2643 <term><literal>EXCLUDE_SRCS</literal></term>
2644 <indexterm><primary><literal>EXCLUDE_SRCS</literal></primary>
2647 <para>Set to a list of source files (relative to the
2648 current directory) to omit from the automatic
2649 search. The source searching machinery is clever
2650 enough to know that if you exclude a source file
2651 from which other sources are derived, then the
2652 derived sources should also be excluded. For
2653 example, if you set <literal>EXCLUDED_SRCS</literal>
2654 to include <filename>Foo.y</filename>, then
2655 <filename>Foo.hs</filename> will also be
2661 <term><literal>EXTRA_SRCS</literal></term>
2662 <indexterm><primary><literal>EXCLUDE_SRCS</literal></primary>
2665 <para>Set to a list of extra source files (perhaps
2666 in directories not listed in
2667 <literal>ALL_DIRS</literal>) that should be
2673 <para>The results of the automatic source file search are
2674 placed in the following make variables:</para>
2678 <term><literal>SRCS</literal></term>
2679 <indexterm><primary><literal>SRCS</literal></primary></indexterm>
2681 <para>All source files found, sorted and without
2682 duplicates, including those which might not exist
2683 yet but will be derived from other existing sources.
2684 <literal>SRCS</literal> <emphasis>can</emphasis> be
2685 overriden if necessary, in which case the variables
2686 below will follow suit.</para>
2691 <term><literal>HS_SRCS</literal></term>
2692 <indexterm><primary><literal>HS_SRCS</literal></primary></indexterm>
2694 <para>all Haskell source files in the current
2695 directory, including those derived from other source
2696 files (eg. Happy sources also give rise to Haskell
2702 <term><literal>HS_OBJS</literal></term>
2703 <indexterm><primary><literal>HS_OBJS</literal></primary></indexterm>
2705 <para>Object files derived from
2706 <literal>HS_SRCS</literal>.</para>
2711 <term><literal>HS_IFACES</literal></term>
2712 <indexterm><primary><literal>HS_IFACES</literal></primary></indexterm>
2714 <para>Interface files (<literal>.hi</literal> files)
2715 derived from <literal>HS_SRCS</literal>.</para>
2720 <term><literal>C_SRCS</literal></term>
2721 <indexterm><primary><literal>C_SRCS</literal></primary></indexterm>
2723 <para>All C source files found.</para>
2728 <term><literal>C_OBJS</literal></term>
2729 <indexterm><primary><literal>C_OBJS</literal></primary></indexterm>
2731 <para>Object files derived from
2732 <literal>C_SRCS</literal>.</para>
2737 <term><literal>SCRIPT_SRCS</literal></term>
2738 <indexterm><primary><literal>SCRIPT_SRCS</literal></primary></indexterm>
2740 <para>All script source files found
2741 (<literal>.lprl</literal> files).</para>
2746 <term><literal>SCRIPT_OBJS</literal></term>
2747 <indexterm><primary><literal>SCRIPT_OBJS</literal></primary></indexterm>
2749 <para><quote>object</quote> files derived from
2750 <literal>SCRIPT_SRCS</literal>
2751 (<literal>.prl</literal> files).</para>
2756 <term><literal>HSC_SRCS</literal></term>
2757 <indexterm><primary><literal>HSC_SRCS</literal></primary></indexterm>
2759 <para>All <literal>hsc2hs</literal> source files
2760 (<literal>.hsc</literal> files).</para>
2765 <term><literal>HAPPY_SRCS</literal></term>
2766 <indexterm><primary><literal>HAPPY_SRCS</literal></primary></indexterm>
2768 <para>All <literal>happy</literal> source files
2769 (<literal>.y</literal> or <literal>.hy</literal> files).</para>
2774 <term><literal>OBJS</literal></term>
2775 <indexterm><primary>OBJS</primary></indexterm>
2777 <para>the concatenation of
2778 <literal>$(HS_OBJS)</literal>,
2779 <literal>$(C_OBJS)</literal>, and
2780 <literal>$(SCRIPT_OBJS)</literal>.</para>
2785 <para>Any or all of these definitions can easily be
2786 overriden by giving new definitions in your
2787 <filename>Makefile</filename>.</para>
2789 <para>What, exactly, does <filename>paths.mk</filename>
2790 consider a <quote>source file</quote> to be? It's based
2791 on the file's suffix (e.g. <filename>.hs</filename>,
2792 <filename>.lhs</filename>, <filename>.c</filename>,
2793 <filename>.hy</filename>, etc), but this is the kind of
2794 detail that changes, so rather than enumerate the source
2795 suffices here the best thing to do is to look in
2796 <filename>paths.mk</filename>.</para>
2801 <term><filename>opts.mk</filename></term>
2802 <indexterm><primary>opts.mk</primary></indexterm>
2804 <para>defines <Command>make</Command> variables for option
2805 strings to pass to each program. For example, it defines
2806 <constant>HC_OPTS</constant><indexterm><primary>HC_OPTS</primary></indexterm>,
2807 the option strings to pass to the Haskell compiler. See
2808 <Xref LinkEnd="sec-suffix">.</para>
2813 <term><filename>suffix.mk</filename></term>
2814 <indexterm><primary>suffix.mk</primary></indexterm>
2816 <para>defines standard pattern rules—see <Xref
2817 LinkEnd="sec-suffix">.</para>
2823 Any of the variables and pattern rules defined by the boilerplate file
2824 can easily be overridden in any particular <filename>Makefile</filename>, because the
2825 boilerplate <Literal>include</Literal> comes first. Definitions after this <Literal>include</Literal>
2826 directive simply override the default ones in <filename>boilerplate.mk</filename>.
2831 <Sect2 id="sec-suffix">
2832 <Title>Pattern rules and options
2834 <indexterm><primary>Pattern rules</primary></indexterm></Title>
2837 The file <filename>suffix.mk</filename><indexterm><primary>suffix.mk</primary></indexterm> defines standard <Emphasis>pattern
2838 rules</Emphasis> that say how to build one kind of file from another, for
2839 example, how to build a <filename>.o</filename> file from a <filename>.c</filename> file. (GNU <Command>make</Command>'s
2840 <Emphasis>pattern rules</Emphasis> are more powerful and easier to use than Unix
2841 <Command>make</Command>'s <Emphasis>suffix rules</Emphasis>.)
2845 Almost all the rules look something like this:
2853 $(CC) $(CC_OPTS) -c $< -o $@
2859 Here's how to understand the rule. It says that
2860 <Emphasis>something</Emphasis><filename>.o</filename> (say <filename>Foo.o</filename>) can be built from
2861 <Emphasis>something</Emphasis><filename>.c</filename> (<filename>Foo.c</filename>), by invoking the C compiler
2862 (path name held in <constant>$(CC)</constant>), passing to it the options
2863 <constant>$(CC_OPTS)</constant> and the rule's dependent file of the rule
2864 <Literal>$<</Literal> (<filename>Foo.c</filename> in this case), and putting the result in
2865 the rule's target <Literal>$@</Literal> (<filename>Foo.o</filename> in this case).
2869 Every program is held in a <Command>make</Command> variable defined in
2870 <filename>mk/config.mk</filename>—look in <filename>mk/config.mk</filename> for the
2871 complete list. One important one is the Haskell compiler, which is
2872 called <constant>$(HC)</constant>.
2876 Every program's options are are held in a <Command>make</Command> variables called
2877 <constant><prog>_OPTS</constant>. the <constant><prog>_OPTS</constant> variables are defined in
2878 <filename>mk/opts.mk</filename>. Almost all of them are defined like this:
2884 CC_OPTS = $(SRC_CC_OPTS) $(WAY$(_way)_CC_OPTS) $($*_CC_OPTS) $(EXTRA_CC_OPTS)
2890 The four variables from which <constant>CC_OPTS</constant> is built have the following meaning:
2897 <term><constant>SRC_CC_OPTS</constant><indexterm><primary>SRC_CC_OPTS</primary></indexterm>:</term>
2900 options passed to all C
2903 </listitem></varlistentry>
2905 <term><constant>WAY_<way>_CC_OPTS</constant>:</term>
2909 compilations for way <Literal><way></Literal>. For example,
2910 <constant>WAY_mp_CC_OPTS</constant> gives options to pass to the C compiler when
2911 compiling way <Literal>mp</Literal>. The variable <constant>WAY_CC_OPTS</constant> holds
2912 options to pass to the C compiler when compiling the standard way.
2913 (<Xref LinkEnd="sec-ways"> dicusses multi-way
2916 </listitem></varlistentry>
2918 <term><constant><module>_CC_OPTS</constant>:</term>
2922 pass to the C compiler that are specific to module <Literal><module></Literal>. For example, <constant>SMap_CC_OPTS</constant> gives the specific options
2923 to pass to the C compiler when compiling <filename>SMap.c</filename>.
2925 </listitem></varlistentry>
2927 <term><constant>EXTRA_CC_OPTS</constant><indexterm><primary>EXTRA_CC_OPTS</primary></indexterm>:</term>
2930 extra options to pass to all
2931 C compilations. This is intended for command line use, thus:
2937 gmake libHS.a EXTRA_CC_OPTS="-v"
2941 </listitem></varlistentry>
2947 <Sect2 id="sec-targets">
2948 <Title>The main <filename>mk/target.mk</filename> file
2950 <indexterm><primary>target.mk</primary></indexterm></Title>
2953 <filename>target.mk</filename> contains canned rules for all the standard targets
2954 described in <Xref LinkEnd="sec-standard-targets">. It is complicated by the fact that you don't want all of
2955 these rules to be active in every <filename>Makefile</filename>. Rather than have a
2956 plethora of tiny files which you can include selectively, there is a
2957 single file, <filename>target.mk</filename>, which selectively includes rules based on
2958 whether you have defined certain variables in your <filename>Makefile</filename>. This
2959 section explains what rules you get, what variables control them, and
2960 what the rules do. Hopefully, you will also get enough of an idea of
2961 what is supposed to happen that you can read and understand any weird
2962 special cases yourself.
2969 <term><constant>HS_PROG</constant><indexterm><primary>HS_PROG</primary></indexterm>.</term>
2972 If <constant>HS_PROG</constant> is defined, you get
2973 rules with the following targets:
2977 <term><filename>HS_PROG</filename><indexterm><primary>HS_PROG</primary></indexterm></term>
2980 itself. This rule links <constant>$(OBJS)</constant>
2981 with the Haskell runtime system to get an executable called
2982 <constant>$(HS_PROG)</constant>.
2984 </listitem></varlistentry>
2986 <term><Literal>install</Literal><indexterm><primary>install</primary></indexterm></term>
2989 installs <constant>$(HS_PROG)</constant>
2990 in <constant>$(bindir)</constant>.
2992 </listitem></varlistentry>
2995 </listitem></varlistentry>
2997 <term><constant>C_PROG</constant><indexterm><primary>C_PROG</primary></indexterm></term>
3000 is similar to <constant>HS_PROG</constant>, except that
3001 the link step links <constant>$(C_OBJS)</constant> with the C runtime system.
3003 </listitem></varlistentry>
3005 <term><constant>LIBRARY</constant><indexterm><primary>LIBRARY</primary></indexterm></term>
3008 is similar to <constant>HS_PROG</constant>, except that
3009 it links <constant>$(LIB_OBJS)</constant> to make the library archive <constant>$(LIBRARY)</constant>, and
3010 <Literal>install</Literal> installs it in <constant>$(libdir)</constant>.
3012 </listitem></varlistentry>
3014 <term><constant>LIB_DATA</constant><indexterm><primary>LIB_DATA</primary></indexterm></term>
3019 </listitem></varlistentry>
3021 <term><constant>LIB_EXEC</constant><indexterm><primary>LIB_EXEC</primary></indexterm></term>
3026 </listitem></varlistentry>
3028 <term><constant>HS_SRCS</constant><indexterm><primary>HS_SRCS</primary></indexterm>, <constant>C_SRCS</constant><indexterm><primary>C_SRCS</primary></indexterm>.</term>
3031 If <constant>HS_SRCS</constant>
3032 is defined and non-empty, a rule for the target <Literal>depend</Literal> is included,
3033 which generates dependency information for Haskell programs.
3034 Similarly for <constant>C_SRCS</constant>.
3036 </listitem></varlistentry>
3041 All of these rules are ``double-colon'' rules, thus
3047 install :: $(HS_PROG)
3048 ...how to install it...
3054 GNU <Command>make</Command> treats double-colon rules as separate entities. If there
3055 are several double-colon rules for the same target it takes each in
3056 turn and fires it if its dependencies say to do so. This means that
3057 you can, for example, define both <constant>HS_PROG</constant> and <constant>LIBRARY</constant>, which will
3058 generate two rules for <Literal>install</Literal>. When you type <Command>gmake install</Command> both
3059 rules will be fired, and both the program and the library will be
3060 installed, just as you wanted.
3065 <Sect2 id="sec-subdirs">
3068 <indexterm><primary>recursion, in makefiles</primary></indexterm>
3069 <indexterm><primary>Makefile, recursing into subdirectories</primary></indexterm></Title>
3072 In leaf <filename>Makefile</filename>s the variable <constant>SUBDIRS</constant><indexterm><primary>SUBDIRS</primary></indexterm> is undefined.
3073 In non-leaf <filename>Makefile</filename>s, <constant>SUBDIRS</constant> is set to the list of
3074 sub-directories that contain subordinate <filename>Makefile</filename>s. <Emphasis>It is up to
3075 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.
3079 When <constant>SUBDIRS</constant> is defined, <filename>target.mk</filename> includes a rather
3080 neat rule for the standard targets (<Xref LinkEnd="sec-standard-targets"> that simply invokes
3081 <Command>make</Command> recursively in each of the sub-directories.
3085 <Emphasis>These recursive invocations are guaranteed to occur in the order
3086 in which the list of directories is specified in <constant>SUBDIRS</constant>. </Emphasis>This
3087 guarantee can be important. For example, when you say <Command>gmake boot</Command> it
3088 can be important that the recursive invocation of <Command>make boot</Command> is done
3089 in one sub-directory (the include files, say) before another (the
3090 source files). Generally, put the most independent sub-directory
3091 first, and the most dependent last.
3096 <Sect2 id="sec-ways">
3097 <Title>Way management
3099 <indexterm><primary>way management</primary></indexterm></Title>
3102 We sometimes want to build essentially the same system in several
3103 different ``ways''. For example, we want to build GHC's <Literal>Prelude</Literal>
3104 libraries with and without profiling, with and without concurrency,
3105 and so on, so that there is an appropriately-built library archive to
3106 link with when the user compiles his program. It would be possible to
3107 have a completely separate build tree for each such ``way'', but it
3108 would be horribly bureaucratic, especially since often only parts of
3109 the build tree need to be constructed in multiple ways.
3113 Instead, the <filename>target.mk</filename><indexterm><primary>target.mk</primary></indexterm> contains some clever magic to
3114 allow you to build several versions of a system; and to control
3115 locally how many versions are built and how they differ. This section
3120 The files for a particular way are distinguished by munging the
3121 suffix. The ``normal way'' is always built, and its files have the
3122 standard suffices <filename>.o</filename>, <filename>.hi</filename>, and so on. In addition, you can build
3123 one or more extra ways, each distinguished by a <Emphasis>way tag</Emphasis>. The
3124 object files and interface files for one of these extra ways are
3125 distinguished by their suffix. For example, way <Literal>mp</Literal> has files
3126 <filename>.mp_o</filename> and <filename>.mp_hi</filename>. Library archives have their way tag the other
3127 side of the dot, for boring reasons; thus, <filename>libHS_mp.a</filename>.
3131 A <Command>make</Command> variable called <constant>way</constant> holds the current way tag. <Emphasis><constant>way</constant>
3132 is only ever set on the command line of a recursive invocation of
3133 <Command>gmake</Command>.</Emphasis> It is never set inside a <filename>Makefile</filename>. So it is a global
3134 constant for any one invocation of <Command>gmake</Command>. Two other <Command>make</Command>
3135 variables, <constant>way_</constant> and <constant>_way</constant> are immediately derived from <constant>$(way)</constant> and
3136 never altered. If <constant>way</constant> is not set, then neither are <constant>way_</constant> and
3137 <constant>_way</constant>, and the invocation of <Command>make</Command> will build the ``normal way''.
3138 If <constant>way</constant> is set, then the other two variables are set in sympathy.
3139 For example, if <constant>$(way)</constant> is ``<Literal>mp</Literal>'', then <constant>way_</constant> is set to ``<Literal>mp_</Literal>''
3140 and <constant>_way</constant> is set to ``<Literal>_mp</Literal>''. These three variables are then used
3141 when constructing file names.
3145 So how does <Command>make</Command> ever get recursively invoked with <constant>way</constant> set? There
3146 are two ways in which this happens:
3155 For some (but not all) of the standard targets, when in a leaf
3156 sub-directory, <Command>make</Command> is recursively invoked for each way tag in
3157 <constant>$(WAYS)</constant>. You set <constant>WAYS</constant> to the list of way tags you want these
3158 targets built for. The mechanism here is very much like the recursive
3159 invocation of <Command>make</Command> in sub-directories (<Xref LinkEnd="sec-subdirs">).
3161 It is up to you to set <constant>WAYS</constant> in your <filename>Makefile</filename>; this is how you
3162 control what ways will get built.
3168 For a useful collection of
3169 targets (such as <filename>libHS_mp.a</filename>, <filename>Foo.mp_o</filename>) there is a rule which
3170 recursively invokes <Command>make</Command> to make the specified target, setting the
3171 <constant>way</constant> variable. So if you say <Command>gmake Foo.mp_o</Command> you should see a
3172 recursive invocation <Command>gmake Foo.mp_o way=mp</Command>, and <Emphasis>in this
3173 recursive invocation the pattern rule for compiling a Haskell file
3174 into a <filename>.o</filename> file will match</Emphasis>. The key pattern rules (in <filename>suffix.mk</filename>)
3180 $(HC) $(HC_OPTS) $< -o $@
3195 <Title>When the canned rule isn't right</Title>
3198 Sometimes the canned rule just doesn't do the right thing. For
3199 example, in the <Literal>nofib</Literal> suite we want the link step to print out
3200 timing information. The thing to do here is <Emphasis>not</Emphasis> to define
3201 <constant>HS_PROG</constant> or <constant>C_PROG</constant>, and instead define a special purpose rule in
3202 your own <filename>Makefile</filename>. By using different variable names you will avoid
3203 the canned rules being included, and conflicting with yours.
3210 <Sect1 id="sec-booting-from-C">
3211 <Title>Booting/porting from C (<filename>.hc</filename>) files
3213 <indexterm><primary>building GHC from .hc files</primary></indexterm>
3214 <indexterm><primary>booting GHC from .hc files</primary></indexterm>
3215 <indexterm><primary>porting GHC</primary></indexterm></Title>
3218 This section is for people trying to get GHC going by using the supplied
3219 intermediate C (<filename>.hc</filename>) files. This would probably be
3220 because no binaries have been provided, or because the machine is not ``fully
3225 The intermediate C files are normally made available together with a source
3226 release, please check the announce message for exact directions of where to
3227 find them. If we haven't made them available or you can't find them, please
3232 Assuming you've got them, unpack them on top of a fresh source tree. This
3233 will place matching <filename>.hc</filename> files next to the corresponding
3234 Haskell source in the compiler subdirectory <filename>ghc</filename> and in
3235 the language package of hslibs (i.e., in <filename>hslibs/lang</filename>).
3236 Then follow the `normal' instructions in <Xref
3237 LinkEnd="sec-building-from-source"> for setting up a build tree.
3241 The actual build process is fully automated by the
3242 <filename>hc-build</filename> script located in the
3243 <filename>distrib</filename> directory. If you eventually want to install GHC
3244 into the directory <filename>INSTALL_DIRECTORY</filename>, the following
3245 command will execute the whole build process (it won't install yet):
3248 foo% distrib/hc-build --prefix=INSTALL_DIRECTORY
3250 <indexterm><primary>--hc-build</primary></indexterm>
3252 By default, the installation directory is <filename>/usr/local</filename>. If
3253 that is what you want, you may omit the argument to
3254 <filename>hc-build</filename>. Generally, any option given to
3255 <filename>hc-build</filename> is passed through to the configuration script
3256 <filename>configure</filename>. If <filename>hc-build</filename>
3257 successfully completes the build process, you can install the resulting
3258 system, as normal, with
3265 That's the mechanics of the boot process, but, of course, if you're
3266 trying to boot on a platform that is not supported and significantly
3267 `different' from any of the supported ones, this is only the start of
3268 the adventure…(ToDo: porting tips—stuff to look out for, etc.)
3273 <Sect1 id="sec-build-pitfalls">
3274 <Title>Known pitfalls in building Glasgow Haskell
3276 <indexterm><primary>problems, building</primary></indexterm>
3277 <indexterm><primary>pitfalls, in building</primary></indexterm>
3278 <indexterm><primary>building pitfalls</primary></indexterm></Title>
3281 WARNINGS about pitfalls and known ``problems'':
3290 One difficulty that comes up from time to time is running out of space
3291 in <literal>TMPDIR</literal>. (It is impossible for the configuration stuff to
3292 compensate for the vagaries of different sysadmin approaches to temp
3294 <indexterm><primary>tmp, running out of space in</primary></indexterm>
3296 The quickest way around it is <Command>setenv TMPDIR /usr/tmp</Command><indexterm><primary>TMPDIR</primary></indexterm> or
3297 even <Command>setenv TMPDIR .</Command> (or the equivalent incantation with your shell
3300 The best way around it is to say
3303 export TMPDIR=<dir>
3306 in your <filename>build.mk</filename> file.
3307 Then GHC and the other <Literal>fptools</Literal> programs will use the appropriate directory
3316 In compiling some support-code bits, e.g., in <filename>ghc/rts/gmp</filename> and even
3317 in <filename>ghc/lib</filename>, you may get a few C-compiler warnings. We think these
3325 When compiling via C, you'll sometimes get ``warning: assignment from
3326 incompatible pointer type'' out of GCC. Harmless.
3333 Similarly, <Command>ar</Command>chiving warning messages like the following are not
3337 ar: filename GlaIOMonad__1_2s.o truncated to GlaIOMonad_
3338 ar: filename GlaIOMonad__2_2s.o truncated to GlaIOMonad_
3348 In compiling the compiler proper (in <filename>compiler/</filename>), you <Emphasis>may</Emphasis>
3349 get an ``Out of heap space'' error message. These can vary with the
3350 vagaries of different systems, it seems. The solution is simple:
3357 If you're compiling with GHC 4.00 or later, then the
3358 <Emphasis>maximum</Emphasis> heap size must have been reached. This
3359 is somewhat unlikely, since the maximum is set to 64M by default.
3360 Anyway, you can raise it with the
3361 <Option>-optCrts-M<size></Option> flag (add this flag to
3362 <constant><module>_HC_OPTS</constant>
3363 <Command>make</Command> variable in the appropriate
3364 <filename>Makefile</filename>).
3371 For GHC < 4.00, add a suitable <Option>-H</Option> flag to the <filename>Makefile</filename>, as
3380 and try again: <Command>gmake</Command>. (see <Xref LinkEnd="sec-suffix"> for information about
3381 <constant><module>_HC_OPTS</constant>.)
3383 Alternatively, just cut to the chase:
3387 % make EXTRA_HC_OPTS=-optCrts-M128M
3396 If you try to compile some Haskell, and you get errors from GCC about
3397 lots of things from <filename>/usr/include/math.h</filename>, then your GCC was
3398 mis-installed. <Command>fixincludes</Command> wasn't run when it should've been.
3400 As <Command>fixincludes</Command> is now automagically run as part of GCC installation,
3401 this bug also suggests that you have an old GCC.
3409 You <Emphasis>may</Emphasis> need to re-<Command>ranlib</Command><indexterm><primary>ranlib</primary></indexterm> your libraries (on Sun4s).
3413 % cd $(libdir)/ghc-x.xx/sparc-sun-sunos4
3414 % foreach i ( `find . -name '*.a' -print` ) # or other-shell equiv...
3416 ? # or, on some machines: ar s $i
3421 We'd be interested to know if this is still necessary.
3429 GHC's sources go through <Command>cpp</Command> before being compiled, and <Command>cpp</Command> varies
3430 a bit from one Unix to another. One particular gotcha is macro calls
3435 SLIT("Hello, world")
3439 Some <Command>cpp</Command>s treat the comma inside the string as separating two macro
3440 arguments, so you get
3444 :731: macro `SLIT' used with too many (2) args
3448 Alas, <Command>cpp</Command> doesn't tell you the offending file!
3450 Workaround: don't put weird things in string args to <Command>cpp</Command> macros.
3461 <Sect1 id="winbuild"><Title>Notes for building under Windows</Title>
3464 This section summarises how to get the utilities you need on your
3465 Win95/98/NT/2000 machine to use CVS and build GHC. Similar notes for
3466 installing and running GHC may be found in the user guide. In general,
3467 Win95/Win98 behave the same, and WinNT/Win2k behave the same.
3468 You should read the GHC installation guide sections on Windows (in the user
3469 guide) before continuing to read these notes.
3473 Because of various hard-wired infelicities, you need to copy
3474 <Filename>bash.exe</Filename> (from GHC's <Filename>extra-bin</Filename>
3475 directory), and <Filename>perl.exe</Filename> and
3476 <Filename>cat.exe</Filename> (from GHC's <Filename>bin</Filename> directory)
3477 to <Filename>/bin</Filename> (discover where your Cygwin root directory is
3478 by typign <Command>mount</Command>).
3482 Before you start, you need to make sure that the user environment variable
3483 <constant>MAKE_MODE</constant> is set to <Literal>UNIX</Literal>. If you
3484 don't do this you get very weird messages when you type
3485 <Command>make</Command>, such as:
3488 /c: /c: No such file or directory</Screen>
3490 <Sect2><Title>Configuring ssh</Title>
3496 Generate a key, by running <filename>c:/user/local/bin/ssh-keygen1</filename>.
3497 This generates a public key in <filename>.ssh/identity.pub</filename>, and a
3498 private key in <filename>.ssh/identity</filename>
3502 In response to the 'Enter passphrase' question, just hit
3503 return (i.e. use an empty passphrase). The passphrase is
3504 a password that protects your private key. But it's a pain
3505 to type this passphrase everytime you use <Command>ssh</Command>, so the best
3506 thing to do is simply to protect your <filename>.ssh</filename> directory, and
3507 <filename>.ssh/identity</filename> from access by anyone else. To do this
3508 right-click your <filename>.ssh</filename> directory, and select Properties.
3509 If you are not on the access control list, add yourself, and
3510 give yourself full permissions (the second panel).
3511 Remove everyone else from the access control list. (Don't
3512 leave them there but deny them access, because 'they' may be
3513 a list that includes you!)
3517 If you have problems running <Command>ssh-keygen1</Command>
3518 from within <Command>bash</Command>, start up <filename>cmd.exe</filename> and run it as follows:
3522 c:\tmp> set CYGWIN32=tty
3523 c:\tmp> c:/user/local/bin/ssh-keygen1
3529 If you don't have an account on <Literal>cvs.haskell.org</Literal>, send
3530 your <filename>.ssh/identity.pub</filename> to the CVS repository administrator
3531 (currently Jeff Lewis <Email>jlewis@galconn.com</Email>). He will set up
3536 If you do have an account on <Literal>cvs.haskell.org</Literal>, use TeraTerm
3537 to logon to it. Once in, copy the
3538 key that <Command>ssh-keygen1</Command> deposited in <filename>/.ssh/identity.pub</filename> into
3539 your <filename>~/.ssh/authorized_keys</filename>. Make sure that the new version
3540 of <filename>authorized_keys</filename> still has 600 file permission.
3549 <Sect2><Title>Configuring CVS</Title>
3555 From the System control panel,
3556 set the following <Emphasis>user</Emphasis> environment variables (see the GHC user guide)
3562 <constant>HOME</constant>: points to your home directory. This is where CVS
3563 will look for its <filename>.cvsrc</filename> file.
3569 <constant>CVS_RSH</constant>: <filename>c:/path_to_ghc/extra-bin/ssh</filename>
3575 <constant>CVSROOT</constant>: <Literal>:ext:username@cvs.haskell.org:/home/cvs/root</Literal>,
3576 where <Literal>username</Literal> is your userid
3582 <constant>CVSEDITOR</constant>: <filename>bin/gnuclient.exe</filename> if you want to use an Emacs buffer for typing in those long commit messages.
3588 <constant>SHELL</constant>: To use bash as the shell in Emacs, you need to
3589 set this to point to <Filename>bash.exe</Filename>.
3598 Put the following in <filename>$HOME/.cvsrc</filename>:
3609 These are the default options for the specified CVS commands,
3610 and represent better defaults than the usual ones. (Feel
3611 free to change them.)
3615 Filenames starting with <filename>.</filename> were illegal in
3616 the 8.3 DOS filesystem, but that restriction should have
3617 been lifted by now (i.e., you're using VFAT or later filesystems.) If
3618 you're still having problems creating it, don't worry; <filename>.cvsrc</filename> is entirely
3625 Try doing <Command>cvs co fpconfig</Command>. All being well, bytes should
3626 start to trickle through, leaving a directory <filename>fptools</filename>
3627 in your current directory. (You can <Command>rm</Command> it if you don't
3628 want to keep it.) The following messages appear to be harmless:
3632 setsockopt IPTOS_LOWDELAY: Invalid argument
3633 setsockopt IPTOS_THROUGHPUT: Invalid argument
3637 At this point I found that CVS tried to invoke a little dialogue with
3638 me (along the lines of `do you want to talk to this host?'), but
3639 for some reason bombed out. This was from a bash shell running in Emacs.
3640 I solved this by invoking a Cygnus shell, and running CVS from there.
3641 Once things are dialogue free, it seems to work OK from within Emacs.
3647 If you want to check out part of large tree, proceed as follows:
3651 cvs -f checkout -l papers
3657 This sequence checks out the <Literal>papers</Literal> module, but none
3658 of its sub-directories.
3659 The "<Option>-l</Option>" flag says not to check out sub-directories.
3660 The "<Option>-f</Option>" flag says not to read the <filename>.cvsrc</filename> file
3661 whose <Option>-P</Option> default (don't check out empty directories) is
3666 The <Command>cvs update</Command> command sucks in a named sub-directory.
3673 There is a very nice graphical front-end to CVS for Win32 platforms,
3674 with a UI that people will be familiar with, at
3675 <ULink URL="http://www.wincvs.org/">wincvs.org</ULink>.
3676 I have not tried it yet.
3682 <Sect2><Title>Building GHC</Title>
3688 You should give the option
3689 <option>--host=i386-unknown-mingw32</option> to
3690 <command>autoconf</command>, so that it doesn't try to
3691 build for Cygwin (unless that's what you really
3692 want). Since it's possible to get into trouble using the
3693 wrong C compiler, it's wise either to avoid installing
3694 Cygwin gcc, or to explicitly specify
3695 <option>--with-gcc=/mingw/bin/gcc</option>.
3701 You have to run <Command>autoconf</Command> both in <filename>fptools</filename>
3702 and in <filename>fptools/ghc</filename>. If you omit the latter step you'll
3703 get an error when you run <filename>./configure</filename>:
3708 creating mk/config.h
3709 mk/config.h is unchanged
3711 running /bin/sh ./configure --cache-file=.././config.cache --srcdir=.
3712 ./configure: ./configure: No such file or directory
3713 configure: error: ./configure failed for ghc
3719 You need <filename>ghc</filename> to be in your <constant>PATH</constant> before you run
3720 <Command>configure</Command>. The InstallShield tells you the path
3721 when you install it.
3730 <title>Building the Windows InstallShield® Installer</title>
3733 This section is intended for GHC developers only; no-one else
3734 should need to build an InstallShield.
3738 Having built a second-stage tree and done <command>make
3739 install</command> on it, open the InstallShield
3740 (<filename>.ism</filename>) file. Open the Project screen, and
3741 then the Project subfolder of the Path variables folder, and
3742 set <literal>SourceFiles</literal> to the top of your
3743 tree. You might also need to set <literal>GHCBITS</literal> to
3744 point to the tree of various external bits that are added into
3745 the IS mix. You should then be able to build an InstallShield.
3749 <title>Extra features of the InstallShield</title>
3752 The InstallShield has some IS-specific twiddles:
3757 Two registry entries are set under
3758 <literal>HKEY_LOCAL_MACHINE\SOFTWARE\GHC</literal>:
3759 <literal>Path</literal> and
3760 <literal>Version</literal>, which record respectively
3761 the directory in which GHC was installed, and the
3767 The InstallShield adds some entries to the Program
3768 menu, for GHCi and for the documentation. See under
3769 Setup Design and the individual components (each
3770 component can add entries to the menu).
3778 <title>External add-ins</title>
3781 The external add-ins consist of Mingwin gcc and Mingwin
3782 Perl. The layout of the add-ins tree is as follows:
3787 perl.exe (Mingwin perl)
3790 Mingwin gcc binaries, libraries and headers