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 sources</title>
35 <para>You can get your hands on the <literal>fptools</literal>
41 <term><indexterm><primary>Source
42 distributions</primary></indexterm>Source distributions</term>
44 <para>You have a supported platform, but (a) you like
45 the warm fuzzy feeling of compiling things yourself;
46 (b) you want to build something ``extra”—e.g., a
47 set of libraries with strictness-analysis turned off; or
48 (c) you want to hack on GHC yourself.</para>
50 <para>A source distribution contains complete sources for
51 one or more projects in the <literal>fptools</literal>
52 suite. Not only that, but the more awkward
53 machine-independent steps are done for you. For example, if
55 <command>happy</command><indexterm><primary>happy</primary></indexterm>
56 you'll find it convenient that the source distribution
57 contains the result of running <command>happy</command> on
58 the parser specifications. If you don't want to alter the
59 parser then this saves you having to find and install
60 <command>happy</command>. You will still need a working
61 version of GHC (version 5.x or later) on your machine in
62 order to compile (most of) the sources, however.</para>
67 <term>The CVS repository.</term>
68 <indexterm><primary>CVS repository</primary>
71 <para>We make releases infrequently. If you want more
72 up-to-the minute (but less tested) source code then you need
73 to get access to our CVS repository.</para>
75 <para>All the <literal>fptools</literal> source code is held
76 in a CVS repository. CVS is a pretty good source-code
77 control system, and best of all it works over the
80 <para>The repository holds source code only. It holds no
81 mechanically generated files at all. So if you check out a
82 source tree from CVS you will need to install every utility
83 so that you can build all the derived files from
86 <para>More information about our CVS repository can be found
87 in <xref linkend="sec-cvs">.</para>
92 <para>If you are going to do any building from sources (either
93 from a source distribution or the CVS repository) then you need to
94 read all of this manual in detail.</para>
98 <title>Using the CVS repository</title>
100 <para>We use <ulink url="http://www.cvshome.org/">CVS</ulink> (Concurrent Version System) to keep track of our
101 sources for various software projects. CVS lets several people
102 work on the same software at the same time, allowing changes to be
103 checked in incrementally. </para>
105 <para>This section is a set of guidelines for how to use our CVS
106 repository, and will probably evolve in time. The main thing to
107 remember is that most mistakes can be undone, but if there's
108 anything you're not sure about feel free to bug the local CVS
109 meister (namely Jeff Lewis
110 <email>jlewis@galconn.com</email>). </para>
112 <sect2 id="cvs-access">
113 <title>Getting access to the CVS Repository</title>
115 <para>You can access the repository in one of two ways:
116 read-only (<xref linkend="cvs-read-only">), or read-write (<xref
117 linkend="cvs-read-write">).</para>
119 <sect3 id="cvs-read-only">
120 <title>Remote Read-only CVS Access</title>
122 <para>Read-only access is available to anyone - there's no
123 need to ask us first. With read-only CVS access you can do
124 anything except commit changes to the repository. You can
125 make changes to your local tree, and still use CVS's merge
126 facility to keep your tree up to date, and you can generate
127 patches using 'cvs diff' in order to send to us for
130 <para>To get read-only access to the repository:</para>
134 <para>Make sure that <application>cvs</application> is
135 installed on your machine.</para>
138 <para>Set your <literal>$CVSROOT</literal> environment variable to
139 <literal>:pserver:anoncvs@glass.cse.ogi.edu:/cvs</literal></para>
140 <para>If you set <literal>$CVSROOT</literal> in a shell script, be sure not to
141 have any trailing spaces on that line, otherwise CVS will respond with
142 a perplexing message like
144 /cvs : no such repository
145 </programlisting></para>
148 <para>Run the command</para>
152 <para>The password is simply <literal>cvs</literal>. This
153 sets up a file in your home directory called
154 <literal>.cvspass</literal>, which squirrels away the
155 dummy password, so you only need to do this step once.</para>
159 <para>Now go to <xref linkend="cvs-first">.</para>
164 <sect3 id="cvs-read-write">
165 <title>Remote Read-Write CVS Access</title>
167 <para>We generally supply read-write access to folk doing
168 serious development on some part of the source tree, when
169 going through us would be a pain. If you're developing some
170 feature, or think you have the time and inclination to fix
171 bugs in our sources, feel free to ask for read-write
172 access. There is a certain amount of responsibility that goes
173 with commit privileges; we are more likely to grant you access
174 if you've demonstrated your competence by sending us patches
175 via mail in the past.</para>
177 <para>To get remote read-write CVS access, you need to do the
178 following steps.</para>
182 <para>Make sure that <literal>cvs</literal> and
183 <literal>ssh</literal> are both installed on your
188 <para>Generate a DSA private-key/public-key pair, thus:</para>
192 <para>(<literal>ssh-keygen</literal> comes with
193 <literal>ssh</literal>.) Running <literal>ssh-keygen
194 -d</literal> creates the private and public keys in
195 <literal>$HOME/.ssh/id_dsa</literal> and
196 <literal>$HOME/.ssh/id_dsa.pub</literal> respectively
197 (assuming you accept the standard defaults).</para>
199 <para><literal>ssh-keygen -d</literal> will only work if
200 you have Version 2 <literal>ssh</literal> installed; it
201 will fail harmlessly otherwise. If you only have Version
202 1 you can instead generate an RSA key pair using plain</para>
207 <para>Doing so creates the private and public RSA keys in
208 <literal>$HOME/.ssh/identity</literal> and
209 <literal>$HOME/.ssh/identity.pub</literal>
212 <para>[Deprecated.] Incidentally, you can force a Version
213 2 <literal>ssh</literal> to use the Version 1 protocol by
214 creating <literal>$HOME/config</literal> with the
215 following in it:</para>
223 <para>In both cases, <literal>ssh-keygen</literal> will
224 ask for a <firstterm>passphrase</firstterm>. The
225 passphrase is a password that protects your private key.
226 In response to the 'Enter passphrase' question, you can
230 <para>[Recommended.] Enter a passphrase, which you
231 will quote each time you use CVS.
232 <literal>ssh-agent</literal> makes this entirely
236 <para>[Deprecated.] Just hit return (i.e. use an empty
237 passphrase); then you won't need to quote the
238 passphrase when using CVS. The downside is that
239 anyone who can see into your <literal>.ssh</literal>
240 directory, and thereby get your private key, can mess
241 up the repository. So you must keep the
242 <literal>.ssh</literal> directory with draconian
243 no-access permissions.</para>
249 <emphasis>Windows users: see the notes in <xref linkend="configure-ssh"> about <command>ssh</command> wrinkles!</emphasis>
256 <para>Send a message to to the CVS repository
257 administrator (currently Jeff Lewis
258 <email>jeff@galconn.com</email>), containing:</para>
261 <para>Your desired user-name.</para>
264 <para>Your <literal>.ssh/id_dsa.pub</literal> (or
265 <literal>.ssh/identity.pub</literal>).</para>
268 <para>He will set up your account.</para>
272 <para>Set the following environment variables:</para>
276 <constant>$HOME</constant>: points to your home directory. This is where CVS
277 will look for its <filename>.cvsrc</filename> file.
283 <constant>$CVS_RSH</constant> to <filename>ssh</filename>
285 <para>[Windows users.] Setting your <literal>CVS_RSH</literal> to
286 <literal>ssh</literal> assumes that your CVS client
287 understands how to execute shell script
288 ("#!"s,really), which is what
289 <literal>ssh</literal> is. This may not be the case on
290 Win32 platforms, so in that case set <literal>CVS_RSH</literal> to
291 <literal>ssh1</literal>.</para>
295 <para><literal>$CVSROOT</literal> to
296 <literal>:ext:</literal><replaceable>your-username</replaceable>
297 <literal>@cvs.haskell.org:/home/cvs/root</literal>
298 where <replaceable>your-username</replaceable> is your user name on
299 <literal>cvs.haskell.org</literal>.
301 <para>The <literal>CVSROOT</literal> environment variable will
302 be recorded in the checked-out tree, so you don't need to set
303 this every time. </para>
309 <constant>$CVSEDITOR</constant>: <filename>bin/gnuclient.exe</filename>
310 if you want to use an Emacs buffer for typing in those long commit messages.
316 <constant>$SHELL</constant>: To use bash as the shell in Emacs, you need to
317 set this to point to <filename>bash.exe</filename>.
328 Put the following in <filename>$HOME/.cvsrc</filename>:
339 These are the default options for the specified CVS commands,
340 and represent better defaults than the usual ones. (Feel
341 free to change them.)
345 [Windows users.] Filenames starting with <filename>.</filename> were illegal in
346 the 8.3 DOS filesystem, but that restriction should have
347 been lifted by now (i.e., you're using VFAT or later filesystems.) If
348 you're still having problems creating it, don't worry; <filename>.cvsrc</filename> is entirely
356 <para>[Experts.] Once your account is set up, you can get
357 access from other machines without bothering Jeff, thus:</para>
360 <para>Generate a public/private key pair on the new
364 <para>Use ssh to log in to
365 <literal>cvs.haskell.org</literal>, from your old
369 <para>Add the public key for the new machine to the file
370 <literal>$HOME/ssh/authorized_keys</literal> on
371 <literal>cvs.haskell.org</literal>.
372 (<literal>authorized_keys2</literal>, I think, for Version
376 <para>Make sure that the new version of
377 <literal>authorized_keys</literal> still has 600 file
386 <sect2 id="cvs-first">
387 <title>Checking Out a Source Tree</title>
391 <para>Make sure you set your <literal>CVSROOT</literal>
392 environment variable according to either of the remote
393 methods above. The Approved Way to check out a source tree
394 is as follows:</para>
397 $ cvs checkout fpconfig
400 <para>At this point you have a new directory called
401 <literal>fptools</literal> which contains the basic stuff
402 for the fptools suite, including the configuration files and
403 some other junk. </para>
405 <para>[Windows users.] The following messages appear to be harmless:
407 setsockopt IPTOS_LOWDELAY: Invalid argument
408 setsockopt IPTOS_THROUGHPUT: Invalid argument
413 <para>You can call the fptools directory whatever you like,
414 CVS won't mind: </para>
417 $ mv fptools <replaceable>directory</replaceable>
420 <para> NB: after you've read the CVS manual you might be
421 tempted to try</para>
423 $ cvs checkout -d <replaceable>directory</replaceable> fpconfig
426 <para>instead of checking out <literal>fpconfig</literal>
427 and then renaming it. But this doesn't work, and will
428 result in checking out the entire repository instead of just
429 the <literal>fpconfig</literal> bit.</para>
431 $ cd <replaceable>directory</replaceable>
432 $ cvs checkout ghc hslibs libraries
435 <para>The second command here checks out the relevant
436 modules you want to work on. For a GHC build, for instance,
437 you need at least the <literal>ghc</literal>,
438 <literal>hslibs</literal> and <literal>libraries</literal>
439 modules (for a full list of the projects available, see
440 <xref linkend="projects">).</para>
442 <para>Remember that if you do not have
443 <literal>happy</literal> and/or <literal>Alex</literal>
444 installed, you need to check them out as well.</para>
449 <sect2 id="cvs-committing">
450 <title>Committing Changes</title>
452 <para>This is only if you have read-write access to the
453 repository. For anoncvs users, CVS will issue a "read-only
454 repository" error if you try to commit changes.</para>
458 <para>Build the software, if necessary. Unless you're just
459 working on documentation, you'll probably want to build the
460 software in order to test any changes you make.</para>
464 <para>Make changes. Preferably small ones first.</para>
468 <para>Test them. You can see exactly what changes you've
469 made by using the <literal>cvs diff</literal> command:</para>
473 <para>lists all the changes (using the
474 <literal>diff</literal> command) in and below the current
475 directory. In emacs, <literal>C-c C-v =</literal> runs
476 <literal>cvs diff</literal> on the current buffer and shows
477 you the results.</para>
481 <para>If you changed something in the
482 <literal>fptools/libraries</literal> subdirectories, also run
483 <literal>make html</literal> to check if the documentation can
484 be generated successfully, too.</para>
488 <para>Before checking in a change, you need to update your
495 <para>This pulls in any changes that other people have made,
496 and merges them with yours. If there are any conflicts, CVS
497 will tell you, and you'll have to resolve them before you
498 can check your changes in. The documentation describes what
499 to do in the event of a conflict.</para>
501 <para>It's not always necessary to do a full cvs update
502 before checking in a change, since CVS will always tell you
503 if you try to check in a file that someone else has changed.
504 However, you should still update at regular intervals to
505 avoid making changes that don't work in conjuction with
506 changes that someone else made. Keeping an eye on what goes
507 by on the mailing list can help here.</para>
511 <para>When you're happy that your change isn't going to
512 break anything, check it in. For a one-file change:</para>
515 $ cvs commit <replaceable>filename</replaceable>
518 <para>CVS will then pop up an editor for you to enter a
519 "commit message", this is just a short description
520 of what your change does, and will be kept in the history of
523 <para>If you're using emacs, simply load up the file into a
524 buffer and type <literal>C-x C-q</literal>, and emacs will
525 prompt for a commit message and then check in the file for
528 <para>For a multiple-file change, things are a bit
529 trickier. There are several ways to do this, but this is the
530 way I find easiest. First type the commit message into a
531 temporary file. Then either</para>
534 $ cvs commit -F <replaceable>commit-message</replaceable> <replaceable>file_1</replaceable> .... <replaceable>file_n</replaceable>
537 <para>or, if nothing else has changed in this part of the
541 $ cvs commit -F <replaceable>commit-message</replaceable> <replaceable>directory</replaceable>
544 <para>where <replaceable>directory</replaceable> is a common
545 parent directory for all your changes, and
546 <replaceable>commit-message</replaceable> is the name of the
547 file containing the commit message.</para>
549 <para>Shortly afterwards, you'll get some mail from the
550 relevant mailing list saying which files changed, and giving
551 the commit message. For a multiple-file change, you should
552 still get only <emphasis>one</emphasis> message.</para>
557 <sect2 id="cvs-update">
558 <title>Updating Your Source Tree</title>
560 <para>It can be tempting to cvs update just part of a source
561 tree to bring in some changes that someone else has made, or
562 before committing your own changes. This is NOT RECOMMENDED!
563 Quite often changes in one part of the tree are dependent on
564 changes in another part of the tree (the
565 <literal>mk/*.mk</literal> files are a good example where
566 problems crop up quite often). Having an inconsistent tree is a
567 major cause of headaches. </para>
569 <para>So, to avoid a lot of hassle, follow this recipe for
570 updating your tree:</para>
574 $ cvs update -P 2>&1 | tee log</screen>
576 <para>Look at the log file, and fix any conflicts (denoted by a
577 <quote>C</quote> in the first column). New directories may have
578 appeared in the repository; CVS doesn't check these out by
579 default, so to get new directories you have to explicitly do
581 $ cvs update -d</screen>
582 in each project subdirectory. Don't do this at the top level,
583 because then <emphasis>all</emphasis> the projects will be
586 <para>If you're using multiple build trees, then for every build
587 tree you have pointing at this source tree, you need to update
588 the links in case any new files have appeared: </para>
591 $ cd <replaceable>build-tree</replaceable>
592 $ lndir <replaceable>source-tree</replaceable>
595 <para>Some files might have been removed, so you need to remove
596 the links pointing to these non-existent files:</para>
599 $ find . -xtype l -exec rm '{}' \;
602 <para>To be <emphasis>really</emphasis> safe, you should do
605 <screen>$ gmake all</screen>
607 <para>from the top-level, to update the dependencies and build
608 any changed files. </para>
611 <sect2 id="cvs-tags">
612 <title>GHC Tag Policy</title>
614 <para>If you want to check out a particular version of GHC,
615 you'll need to know how we tag versions in the repository. The
616 policy (as of 4.04) is:</para>
620 <para>The tree is branched before every major release. The
621 branch tag is <literal>ghc-x-xx-branch</literal>, where
622 <literal>x-xx</literal> is the version number of the release
623 with the <literal>'.'</literal> replaced by a
624 <literal>'-'</literal>. For example, the 4.04 release lives
625 on <literal>ghc-4-04-branch</literal>.</para>
629 <para>The release itself is tagged with
630 <literal>ghc-x-xx</literal> (on the branch). eg. 4.06 is
631 called <literal>ghc-4-06</literal>.</para>
635 <para>We didn't always follow these guidelines, so to see
636 what tags there are for previous versions, do <literal>cvs
637 log</literal> on a file that's been around for a while (like
638 <literal>fptools/ghc/README</literal>).</para>
642 <para>So, to check out a fresh GHC 4.06 tree you would
646 $ cvs co -r ghc-4-06 fpconfig
648 $ cvs co -r ghc-4-06 ghc hslibs
652 <sect2 id="cvs-hints">
653 <title>General Hints</title>
657 <para>As a general rule: commit changes in small units,
658 preferably addressing one issue or implementing a single
659 feature. Provide a descriptive log message so that the
660 repository records exactly which changes were required to
661 implement a given feature/fix a bug. I've found this
662 <emphasis>very</emphasis> useful in the past for finding out
663 when a particular bug was introduced: you can just wind back
664 the CVS tree until the bug disappears.</para>
668 <para>Keep the sources at least *buildable* at any given
669 time. No doubt bugs will creep in, but it's quite easy to
670 ensure that any change made at least leaves the tree in a
671 buildable state. We do nightly builds of GHC to keep an eye
672 on what things work/don't work each day and how we're doing
673 in relation to previous verions. This idea is truely wrecked
674 if the compiler won't build in the first place!</para>
678 <para>To check out extra bits into an already-checked-out
679 tree, use the following procedure. Suppose you have a
680 checked-out fptools tree containing just ghc, and you want
681 to add nofib to it:</para>
692 $ cvs update -d nofib
695 <para>(the -d flag tells update to create a new
696 directory). If you just want part of the nofib suite, you
701 $ cvs checkout nofib/spectral
704 <para>This works because <literal>nofib</literal> is a
705 module in its own right, and spectral is a subdirectory of
706 the nofib module. The path argument to checkout must always
707 start with a module name. There's no equivalent form of this
708 command using <literal>update</literal>.</para>
714 <sect1 id="projects">
715 <title>What projects are there?</title>
717 <para>The <literal>fptools</literal> suite consists of several
718 <firstterm>projects</firstterm>, most of which can be downloaded,
719 built and installed individually. Each project corresponds to a
720 subdirectory in the source tree, and if checking out from CVS then
721 each project can be checked out individually by sitting in the top
722 level of your source tree and typing <command>cvs checkout
723 <replaceable>project</replaceable></command>.</para>
725 <para>Here is a list of the projects currently available:</para>
729 <term><literal>alex</literal></term>
730 <indexterm><primary><literal>alex</literal></primary>
731 <secondary>project</secondary></indexterm>
734 url="http://www.haskell.org/alex/">Alex</ulink> lexical
735 analyser generator for Haskell.</para>
740 <term><literal>ghc</literal></term>
741 <indexterm><primary><literal>ghc</literal></primary>
742 <secondary>project</secondary></indexterm>
744 <para>The <ulink url="http://www.haskell.org/ghc/">Glasgow
745 Haskell Compiler</ulink> (minus libraries). Absolutely
746 required for building GHC.</para>
751 <term><literal>glafp-utils</literal></term>
752 <indexterm><primary><literal>glafp-utils</literal></primary><secondary>project</secondary></indexterm>
754 <para>Utility programs, some of which are used by the
755 build/installation system. Required for pretty much
761 <term><literal>greencard</literal></term>
762 <indexterm><primary><literal>greencard</literal></primary><secondary>project</secondary></indexterm>
765 url="http://www.haskell.org/greencard/">GreenCard</ulink>
766 system for generating Haskell foreign function
772 <term><literal>haggis</literal></term>
773 <indexterm><primary><literal>haggis</literal></primary><secondary>project</secondary></indexterm>
776 url="http://www.dcs.gla.ac.uk/fp/software/haggis/">Haggis</ulink>
777 Haskell GUI framework.</para>
782 <term><literal>haddock</literal></term>
783 <indexterm><primary><literal>haddock</literal></primary><secondary>project</secondary></indexterm>
786 url="http://www.haskell.org/haddock/">Haddock</ulink>
787 documentation tool.</para>
792 <term><literal>happy</literal></term>
793 <indexterm><primary><literal>happy</literal></primary><secondary>project</secondary></indexterm>
796 url="http://www.haskell.org/happy/">Happy</ulink> Parser
802 <term><literal>hdirect</literal></term>
803 <indexterm><primary><literal>hdirect</literal></primary><secondary>project</secondary></indexterm>
806 url="http://www.haskell.org/hdirect/">H/Direct</ulink>
807 Haskell interoperability tool.</para>
812 <term><literal>hood</literal></term>
813 <indexterm><primary><literal>hood</literal></primary><secondary>project</secondary></indexterm>
815 <para>The <ulink url="http://www.haskell.org/hood/">Haskell
816 Object Observation Debugger</ulink>.</para>
821 <term><literal>hslibs</literal></term>
822 <indexterm><primary><literal>hslibs</literal></primary><secondary>project</secondary></indexterm>
824 <para>Supplemental libraries for GHC
825 (<emphasis>required</emphasis> for building GHC).</para>
830 <term><literal>libraries</literal></term>
831 <indexterm><primary><literal></literal></primary><secondary>project</secondary></indexterm>
833 <para>Hierarchical Haskell library suite
834 (<emphasis>required</emphasis> for building GHC).</para>
839 <term><literal>mhms</literal></term>
840 <indexterm><primary><literal></literal></primary><secondary>project</secondary></indexterm>
842 <para>The Modular Haskell Metric System.</para>
847 <term><literal>nofib</literal></term>
848 <indexterm><primary><literal>nofib</literal></primary><secondary>project</secondary></indexterm>
850 <para>The NoFib suite: A collection of Haskell programs used
851 primarily for benchmarking.</para>
856 <term><literal>testsuite</literal></term>
857 <indexterm><primary><literal>testsuite</literal></primary><secondary>project</secondary></indexterm>
859 <para>A testing framework, including GHC's regression test
865 <para>So, to build GHC you need at least the
866 <literal>ghc</literal>, <literal>libraries</literal> and
867 <literal>hslibs</literal> projects (a GHC source distribution will
868 already include the bits you need).</para>
871 <sect1 id="sec-build-checks">
872 <title>Things to check before you start</title>
874 <para>Here's a list of things to check before you get
880 <indexterm><primary>Disk space needed</primary></indexterm>
881 <para>Disk space needed: from about 100Mb for a basic GHC
882 build, up to probably 500Mb for a GHC build with everything
883 included (libraries built several different ways,
888 <para>Use an appropriate machine / operating system. <xref
889 linkend="sec-port-info"> lists the supported platforms; if
890 yours isn't amongst these then you can try porting GHC (see
891 <xref linkend="sec-porting-ghc">).</para>
895 <para>Be sure that the “pre-supposed” utilities are
896 installed. <Xref LinkEnd="sec-pre-supposed">
901 <para>If you have any problem when building or installing the
902 Glasgow tools, please check the “known pitfalls” (<Xref
903 LinkEnd="sec-build-pitfalls">). Also check the FAQ for the
904 version you're building, which is part of the User's Guide and
905 available on the <ulink URL="http://www.haskell.org/ghc/" >GHC web
908 <indexterm><primary>bugs</primary><secondary>known</secondary></indexterm>
910 <para>If you feel there is still some shortcoming in our
911 procedure or instructions, please report it.</para>
913 <para>For GHC, please see the <ulink
914 url="http://www.haskell.org/ghc/docs/latest/set/bug-reporting.html">bug-reporting
915 section of the GHC Users' Guide</ulink>, to maximise the
916 usefulness of your report.</para>
918 <indexterm><primary>bugs</primary><secondary>seporting</secondary></indexterm>
919 <para>If in doubt, please send a message to
920 <email>glasgow-haskell-bugs@haskell.org</email>.
921 <indexterm><primary>bugs</primary><secondary>mailing
922 list</secondary></indexterm></para>
927 <sect1 id="sec-port-info">
928 <title>What machines the Glasgow tools run on</title>
930 <indexterm><primary>ports</primary><secondary>GHC</secondary></indexterm>
931 <indexterm><primary>GHC</primary><secondary>ports</secondary></indexterm>
932 <indexterm><primary>platforms</primary><secondary>supported</secondary></indexterm>
934 <para>The main question is whether or not the Haskell compiler
935 (GHC) runs on your platform.</para>
937 <para>A “platform” is a
938 architecture/manufacturer/operating-system combination, such as
939 <literal>sparc-sun-solaris2</literal>. Other common ones are
940 <literal>alpha-dec-osf2</literal>,
941 <literal>hppa1.1-hp-hpux9</literal>,
942 <literal>i386-unknown-linux</literal>,
943 <literal>i386-unknown-solaris2</literal>,
944 <literal>i386-unknown-freebsd</literal>,
945 <literal>i386-unknown-cygwin32</literal>,
946 <literal>m68k-sun-sunos4</literal>,
947 <literal>mips-sgi-irix5</literal>,
948 <literal>sparc-sun-sunos4</literal>,
949 <literal>sparc-sun-solaris2</literal>,
950 <literal>powerpc-ibm-aix</literal>.</para>
952 <para>Some libraries may only work on a limited number of
953 platforms; for example, a sockets library is of no use unless the
954 operating system supports the underlying BSDisms.</para>
957 <title>What platforms the Haskell compiler (GHC) runs on</title>
959 <indexterm><primary>fully-supported platforms</primary></indexterm>
960 <indexterm><primary>native-code generator</primary></indexterm>
961 <indexterm><primary>registerised ports</primary></indexterm>
962 <indexterm><primary>unregisterised ports</primary></indexterm>
964 <para>The GHC hierarchy of Porting Goodness: (a) Best is a
965 native-code generator; (b) next best is a
966 “registerised” port; (c) the bare minimum is an
967 “unregisterised” port.
968 (“Unregisterised” is so terrible that we won't say
969 more about it).</para>
971 <para>We use Sparcs running Solaris 2.7 and x86 boxes running
972 FreeBSD and Linux, so those are the best supported platforms,
973 unsurprisingly.</para>
975 <para>Here's everything that's known about GHC ports. We
976 identify platforms by their “canonical”
977 CPU/Manufacturer/OS triple.</para>
981 <term>alpha-dec-{osf,linux,freebsd,openbsd,netbsd}:</term>
982 <indexterm><primary>alpha-dec-osf</primary></indexterm>
983 <indexterm><primary>alpha-dec-linux</primary></indexterm>
984 <indexterm><primary>alpha-dec-freebsd</primary></indexterm>
985 <indexterm><primary>alpha-dec-openbsd</primary></indexterm>
986 <indexterm><primary>alpha-dec-netbsd</primary></indexterm>
989 <para>The OSF port is currently working (as of GHC version
990 5.02.1) and well supported. The native code generator is
991 currently non-working. Other operating systems will
992 require some minor porting.</para>
997 <term>sparc-sun-sunos4</term>
998 <indexterm><primary>sparc-sun-sunos4</primary></indexterm>
1000 <para>Probably works with minor tweaks, hasn't been tested
1006 <term>sparc-sun-solaris2</term>
1007 <indexterm><primary>sparc-sun-solaris2</primary></indexterm>
1009 <para>Fully supported (at least for Solaris 2.7 and 2.6),
1010 including native-code generator.</para>
1015 <term>sparc-unknown-openbsd</term>
1016 <indexterm><primary>sparc-unknown-openbsd</primary></indexterm>
1018 <para>Supported, including native-code generator. The
1019 same should also be true of NetBSD</para>
1024 <term>hppa1.1-hp-hpux (HP-PA boxes running HPUX 9.x)</term>
1025 <indexterm><primary>hppa1.1-hp-hpux</primary></indexterm>
1027 <para>A registerised port is available for version 4.08,
1028 but GHC hasn't been built on that platform since (as far
1029 as we know). No native-code generator.</para>
1034 <term>i386-unknown-linux (PCs running Linux, ELF binary format)</term>
1035 <indexterm><primary>i386-*-linux</primary></indexterm>
1037 <para>GHC works registerised and has a native code
1038 generator. You <Emphasis>must</Emphasis> have GCC 2.7.x
1039 or later. NOTE about <literal>glibc</literal> versions:
1040 GHC binaries built on a system running <literal>glibc
1041 2.0</literal> won't work on a system running
1042 <literal>glibc 2.1</literal>, and vice versa. In general,
1043 don't expect compatibility between
1044 <literal>glibc</literal> versions, even if the shared
1045 library version hasn't changed.</para>
1050 <term>i386-unknown-freebsd (PCs running FreeBSD 2.2 or
1052 <indexterm><primary>i386-unknown-freebsd</primary></indexterm>
1054 <para>GHC works registerised. Pre-built packages are
1055 available in the native package format, so if you just
1056 need binaries you're better off just installing the
1057 package (it might even be on your installation
1063 <term>i386-unknown-openbsd (PCs running OpenBSD)</term>
1064 <indexterm><primary>i386-unknown-openbsd</primary></indexterm>
1066 <para>Supported, with native code generator. Packages are
1067 available through the ports system in the native package
1073 <term>i386-unknown-netbsd (PCs running NetBSD and
1075 <indexterm><primary>i386-unknown-netbsd</primary></indexterm>
1077 <para>Will require some minor porting effort, but should
1078 work registerised.</para>
1083 <term>i386-unknown-mingw32 (PCs running Windows)</term>
1084 <indexterm><primary>i386-unknown-mingw32</primary></indexterm>
1086 <para>Fully supported under Win9x, WinNT, Win2k, and
1087 WinXP. Includes a native code generator. Building from
1088 source requires a recent <ulink
1089 url="http://www.cygwin.com/">Cygwin</ulink> distribution
1090 to be installed.</para>
1095 <term>ia64-unknown-linux</term>
1096 <indexterm><primary>ia64-unknown-linux</primary></indexterm>
1098 <para>Supported, except there is no native code
1104 <term>x86_64-unknown-linux</term>
1105 <indexterm><primary>x86_64-unknown-linux</primary></indexterm>
1107 <para>GHC currently works unregisterised. A registerised
1108 port is in progress.</para>
1113 <term>mips-sgi-irix5</term>
1114 <indexterm><primary>mips-sgi-irix[5-6]</primary></indexterm>
1116 <para>Port has worked in the past, but hasn't been tested
1117 for some time (and will certainly have rotted in various
1118 ways). As usual, we don't have access to machines and
1119 there hasn't been an overwhelming demand for this port,
1120 but feel free to get in touch.</para>
1125 <term>mips64-sgi-irix6</term>
1126 <indexterm><primary>mips-sgi-irix6</primary></indexterm>
1128 <para>GHC currently works unregisterised.</para>
1133 <term>powerpc-ibm-aix</term>
1134 <indexterm><primary>powerpc-ibm-aix</primary></indexterm>
1136 <para>Port currently doesn't work, needs some minimal
1137 porting effort. As usual, we don't have access to
1138 machines and there hasn't been an overwhelming demand for
1139 this port, but feel free to get in touch.</para>
1144 <term>powerpc-apple-darwin</term>
1145 <indexterm><primary>powerpc-apple-darwin</primary></indexterm>
1147 <para>Supported registerised. Native code generator is
1148 almost working.</para>
1153 <term>powerpc-apple-linux</term>
1154 <indexterm><primary>powerpc-apple-linux</primary></indexterm>
1156 <para>Not supported (yet).</para>
1161 <para>Various other systems have had GHC ported to them in the
1162 distant past, including various Motorola 68k boxes. The 68k
1163 support still remains, but porting to one of these systems will
1164 certainly be a non-trivial task.</para>
1168 <title>What machines the other tools run on</title>
1170 <para>Unless you hear otherwise, the other tools work if GHC
1176 <sect1 id="sec-pre-supposed">
1177 <title>Installing pre-supposed utilities</title>
1179 <indexterm><primary>pre-supposed utilities</primary></indexterm>
1180 <indexterm><primary>utilities, pre-supposed</primary></indexterm>
1182 <para>Here are the gory details about some utility programs you
1183 may need; <command>perl</command>, <command>gcc</command> and
1184 <command>happy</command> are the only important
1185 ones. (PVM<indexterm><primary>PVM</primary></indexterm> is
1186 important if you're going for Parallel Haskell.) The
1187 <command>configure</command><indexterm><primary>configure</primary></indexterm>
1188 script will tell you if you are missing something.</para>
1194 <indexterm><primary>pre-supposed: GHC</primary></indexterm>
1195 <indexterm><primary>GHC, pre-supposed</primary></indexterm>
1197 <para>GHC is required to build many of the tools, including
1198 GHC itself. If you need to port GHC to your platform
1199 because there isn't a binary distribution of GHC available,
1200 then see <xref linkend="sec-porting-ghc">.</para>
1202 <para>Which version of GHC you need will depend on the
1203 packages you intend to build. GHC itself will normally
1204 build using one of several older versions of itself - check
1205 the announcement or release notes for details.</para>
1211 <indexterm><primary>pre-supposed: Perl</primary></indexterm>
1212 <indexterm><primary>Perl, pre-supposed</primary></indexterm>
1214 <para><emphasis>You have to have Perl to proceed!</emphasis>
1215 Perl version 5 at least is required. GHC has been known to
1216 tickle bugs in Perl, so if you find that Perl crashes when
1217 running GHC try updating (or downgrading) your Perl
1218 installation. Versions of Perl that we use and are known to
1219 be fairly stable are 5.005 and 5.6.1.</para>
1221 <para>For Win32 platforms, you should use the binary
1222 supplied in the InstallShield (copy it to
1223 <filename>/bin</filename>). The Cygwin-supplied Perl seems
1226 <para>Perl should be put somewhere so that it can be invoked
1227 by the <literal>#!</literal> script-invoking
1228 mechanism. The full pathname may need to be less than 32
1229 characters long on some systems.</para>
1234 <term>GNU C (<command>gcc</command>)</term>
1235 <indexterm><primary>pre-supposed: GCC (GNU C
1236 compiler)</primary></indexterm> <indexterm><primary>GCC (GNU C
1237 compiler), pre-supposed</primary></indexterm>
1239 <para>We recommend using GCC version 2.95.2 on all
1240 platforms. Failing that, version 2.7.2 is stable on most
1241 platforms. Earlier versions of GCC can be assumed not to
1242 work, and versions in between 2.7.2 and 2.95.2 (including
1243 <command>egcs</command>) have varying degrees of stability
1244 depending on the platform.</para>
1246 <para>GCC 3.2 is currently known to have problems building
1247 GHC on Sparc, but is stable on x86.</para>
1249 <para>If your GCC dies with “internal error” on
1250 some GHC source file, please let us know, so we can report
1251 it and get things improved. (Exception: on x86
1252 boxes—you may need to fiddle with GHC's
1253 <option>-monly-N-regs</option> option; see the User's
1259 <term>GNU Make</term>
1260 <indexterm><primary>make</primary><secondary>GNU</secondary>
1263 <para>The fptools build system makes heavy use of features
1264 specific to GNU <command>make</command>, so you must have
1265 this installed in order to build any of the fptools
1272 <indexterm><primary>Happy</primary></indexterm>
1274 <para>Happy is a parser generator tool for Haskell, and is
1275 used to generate GHC's parsers. Happy is written in
1276 Haskell, and is a project in the CVS repository
1277 (<literal>fptools/happy</literal>). It can be built from
1278 source, but bear in mind that you'll need GHC installed in
1279 order to build it. To avoid the chicken/egg problem,
1280 install a binary distribution of either Happy or GHC to get
1281 started. Happy distributions are available from <ulink
1282 url="http://www.haskell.org/happy/">Happy's Web
1283 Page</ulink>.</para>
1289 <indexterm><primary>Alex</primary></indexterm>
1291 <para>Alex is a lexical-analyser generator for Haskell,
1292 which GHC uses to generate its lexer. Like Happy, Alex is
1293 written in Haskell and is a project in the CVS repository.
1294 Alex distributions are available from <ulink
1295 url="http://www.haskell.org/alex/">Alex's Web
1296 Page</ulink>.</para>
1301 <term>Autoreconf</term>
1302 <indexterm><primary>pre-supposed: Autoreconf</primary></indexterm>
1303 <indexterm><primary>Autoreconf, pre-supposed</primary></indexterm>
1305 <para>GNU Autoreconf is needed if you intend to build from the
1306 CVS sources, it is <emphasis>not</emphasis> needed if you
1307 just intend to build a standard source distribution.</para>
1309 <para>Version 2.52 or later of autoreconf is required.
1310 NB. vesrion 2.13 will no longer work, as of GHC version
1313 <para>Autoreconf builds the <command>configure</command>
1314 script from <filename>configure.ac</filename> and
1315 <filename>aclocal.m4</filename>. If you modify either of
1316 these files, you'll need <command>autoreconf</command> to
1317 rebuild <filename>configure</filename>.</para>
1322 <term><command>sed</command></term>
1323 <indexterm><primary>pre-supposed: sed</primary></indexterm>
1324 <indexterm><primary>sed, pre-supposed</primary></indexterm>
1326 <para>You need a working <command>sed</command> if you are
1327 going to build from sources. The build-configuration stuff
1328 needs it. GNU sed version 2.0.4 is no good! It has a bug
1329 in it that is tickled by the build-configuration. 2.0.5 is
1330 OK. Others are probably OK too (assuming we don't create too
1331 elaborate configure scripts.)</para>
1336 <para>One <literal>fptools</literal> project is worth a quick note
1337 at this point, because it is useful for all the others:
1338 <literal>glafp-utils</literal> contains several utilities which
1339 aren't particularly Glasgow-ish, but Occasionally Indispensable.
1340 Like <command>lndir</command> for creating symbolic link
1343 <sect2 id="pre-supposed-gph-tools">
1344 <title>Tools for building parallel GHC (GPH)</title>
1348 <term>PVM version 3:</term>
1349 <indexterm><primary>pre-supposed: PVM3 (Parallel Virtual Machine)</primary></indexterm>
1350 <indexterm><primary>PVM3 (Parallel Virtual Machine), pre-supposed</primary></indexterm>
1352 <para>PVM is the Parallel Virtual Machine on which
1353 Parallel Haskell programs run. (You only need this if you
1354 plan to run Parallel Haskell. Concurrent Haskell, which
1355 runs concurrent threads on a uniprocessor doesn't need
1356 it.) Underneath PVM, you can have (for example) a network
1357 of workstations (slow) or a multiprocessor box
1360 <para>The current version of PVM is 3.3.11; we use 3.3.7.
1361 It is readily available on the net; I think I got it from
1362 <literal>research.att.com</literal>, in
1363 <filename>netlib</filename>.</para>
1365 <para>A PVM installation is slightly quirky, but easy to
1366 do. Just follow the <filename>Readme</filename>
1367 instructions.</para>
1372 <term><command>bash</command>:</term>
1373 <indexterm><primary>bash, presupposed (Parallel Haskell only)</primary></indexterm>
1375 <para>Sadly, the <command>gr2ps</command> script, used to
1376 convert “parallelism profiles” to PostScript,
1377 is written in Bash (GNU's Bourne Again shell). This bug
1378 will be fixed (someday).</para>
1384 <sect2 id="pre-supposed-other-tools">
1385 <title>Other useful tools</title>
1390 <indexterm><primary>pre-supposed: flex</primary></indexterm>
1391 <indexterm><primary>flex, pre-supposed</primary></indexterm>
1393 <para>This is a quite-a-bit-better-than-Lex lexer. Used
1394 to build a couple of utilities in
1395 <literal>glafp-utils</literal>. Depending on your
1396 operating system, the supplied <command>lex</command> may
1397 or may not work; you should get the GNU version.</para>
1402 <para>More tools are required if you want to format the documentation
1403 that comes with GHC and other fptools projects. See <xref
1404 linkend="building-docs">.</para>
1408 <sect1 id="sec-building-from-source">
1409 <title>Building from source</title>
1411 <indexterm><primary>Building from source</primary></indexterm>
1412 <indexterm><primary>Source, building from</primary></indexterm>
1414 <para>You've been rash enough to want to build some of the Glasgow
1415 Functional Programming tools (GHC, Happy, nofib, etc.) from
1416 source. You've slurped the source, from the CVS repository or
1417 from a source distribution, and now you're sitting looking at a
1418 huge mound of bits, wondering what to do next.</para>
1420 <para>Gingerly, you type <command>make</command>. Wrong
1423 <para>This rest of this guide is intended for duffers like me, who
1424 aren't really interested in Makefiles and systems configurations,
1425 but who need a mental model of the interlocking pieces so that
1426 they can make them work, extend them consistently when adding new
1427 software, and lay hands on them gently when they don't
1430 <sect2 id="quick-start">
1431 <title>Quick Start</title>
1433 <para>If you are starting from a source distribution, and just
1434 want a completely standard build, then the following should
1437 <screen>$ autoreconf
1443 <para>For GHC, this will do a 2-stage bootstrap build of the
1444 compiler, with profiling libraries, and install the
1447 <para>If you want to do anything at all non-standard, or you
1448 want to do some development, read on...</para>
1451 <sect2 id="sec-source-tree">
1452 <title>Your source tree</title>
1454 <para>The source code is held in your <emphasis>source
1455 tree</emphasis>. The root directory of your source tree
1456 <emphasis>must</emphasis> contain the following directories and
1461 <para><filename>Makefile</filename>: the root
1466 <para><filename>mk/</filename>: the directory that contains
1467 the main Makefile code, shared by all the
1468 <literal>fptools</literal> software.</para>
1472 <para><filename>configure.ac</filename>,
1473 <filename>config.sub</filename>,
1474 <filename>config.guess</filename>: these files support the
1475 configuration process.</para>
1479 <para><filename>install-sh</filename>.</para>
1483 <para>All the other directories are individual
1484 <emphasis>projects</emphasis> of the <literal>fptools</literal>
1485 system—for example, the Glasgow Haskell Compiler
1486 (<literal>ghc</literal>), the Happy parser generator
1487 (<literal>happy</literal>), the <literal>nofib</literal>
1488 benchmark suite, and so on. You can have zero or more of these.
1489 Needless to say, some of them are needed to build others.</para>
1491 <para>The important thing to remember is that even if you want
1492 only one project (<literal>happy</literal>, say), you must have
1493 a source tree whose root directory contains
1494 <filename>Makefile</filename>, <filename>mk/</filename>,
1495 <filename>configure.ac</filename>, and the project(s) you want
1496 (<filename>happy/</filename> in this case). You cannot get by
1497 with just the <filename>happy/</filename> directory.</para>
1501 <title>Build trees</title>
1502 <indexterm><primary>build trees</primary></indexterm>
1503 <indexterm><primary>link trees, for building</primary></indexterm>
1505 <para>If you just want to build the software once on a single
1506 platform, then your source tree can also be your build tree, and
1507 you can skip the rest of this section.</para>
1509 <para>We often want to build multiple versions of our software
1510 for different architectures, or with different options
1511 (e.g. profiling). It's very desirable to share a single copy of
1512 the source code among all these builds.</para>
1514 <para>So for every source tree we have zero or more
1515 <emphasis>build trees</emphasis>. Each build tree is initially
1516 an exact copy of the source tree, except that each file is a
1517 symbolic link to the source file, rather than being a copy of
1518 the source file. There are “standard” Unix
1519 utilities that make such copies, so standard that they go by
1521 <command>lndir</command><indexterm><primary>lndir</primary></indexterm>,
1522 <command>mkshadowdir</command><indexterm><primary>mkshadowdir</primary></indexterm>
1523 are two (If you don't have either, the source distribution
1524 includes sources for the X11
1525 <command>lndir</command>—check out
1526 <filename>fptools/glafp-utils/lndir</filename>). See <Xref
1527 LinkEnd="sec-storysofar"> for a typical invocation.</para>
1529 <para>The build tree does not need to be anywhere near the
1530 source tree in the file system. Indeed, one advantage of
1531 separating the build tree from the source is that the build tree
1532 can be placed in a non-backed-up partition, saving your systems
1533 support people from backing up untold megabytes of
1534 easily-regenerated, and rapidly-changing, gubbins. The golden
1535 rule is that (with a single exception—<XRef
1536 LinkEnd="sec-build-config">) <emphasis>absolutely everything in
1537 the build tree is either a symbolic link to the source tree, or
1538 else is mechanically generated</emphasis>. It should be
1539 perfectly OK for your build tree to vanish overnight; an hour or
1540 two compiling and you're on the road again.</para>
1542 <para>You need to be a bit careful, though, that any new files
1543 you create (if you do any development work) are in the source
1544 tree, not a build tree!</para>
1546 <para>Remember, that the source files in the build tree are
1547 <emphasis>symbolic links</emphasis> to the files in the source
1548 tree. (The build tree soon accumulates lots of built files like
1549 <filename>Foo.o</filename>, as well.) You can
1550 <emphasis>delete</emphasis> a source file from the build tree
1551 without affecting the source tree (though it's an odd thing to
1552 do). On the other hand, if you <emphasis>edit</emphasis> a
1553 source file from the build tree, you'll edit the source-tree
1554 file directly. (You can set up Emacs so that if you edit a
1555 source file from the build tree, Emacs will silently create an
1556 edited copy of the source file in the build tree, leaving the
1557 source file unchanged; but the danger is that you think you've
1558 edited the source file whereas actually all you've done is edit
1559 the build-tree copy. More commonly you do want to edit the
1560 source file.)</para>
1562 <para>Like the source tree, the top level of your build tree
1563 must be (a linked copy of) the root directory of the
1564 <literal>fptools</literal> suite. Inside Makefiles, the root of
1565 your build tree is called
1566 <constant>$(FPTOOLS_TOP)</constant><indexterm><primary>FPTOOLS_TOP</primary></indexterm>.
1567 In the rest of this document path names are relative to
1568 <constant>$(FPTOOLS_TOP)</constant> unless
1569 otherwise stated. For example, the file
1570 <filename>ghc/mk/target.mk</filename> is actually
1571 <filename><constant>$(FPTOOLS_TOP)</constant>/ghc/mk/target.mk</filename>.</para>
1574 <sect2 id="sec-build-config">
1575 <title>Getting the build you want</title>
1577 <para>When you build <literal>fptools</literal> you will be
1578 compiling code on a particular <emphasis>host
1579 platform</emphasis>, to run on a particular <emphasis>target
1580 platform</emphasis> (usually the same as the host
1581 platform)<indexterm><primary>platform</primary></indexterm>.
1582 The difficulty is that there are minor differences between
1583 different platforms; minor, but enough that the code needs to be
1584 a bit different for each. There are some big differences too:
1585 for a different architecture we need to build GHC with a
1586 different native-code generator.</para>
1588 <para>There are also knobs you can turn to control how the
1589 <literal>fptools</literal> software is built. For example, you
1590 might want to build GHC optimised (so that it runs fast) or
1591 unoptimised (so that you can compile it fast after you've
1592 modified it. Or, you might want to compile it with debugging on
1593 (so that extra consistency-checking code gets included) or off.
1596 <para>All of this stuff is called the
1597 <emphasis>configuration</emphasis> of your build. You set the
1598 configuration using a three-step process.</para>
1602 <term>Step 1: get ready for configuration.</term>
1604 <para>NOTE: if you're starting from a source distribution,
1605 rather than CVS sources, you can skip this step.</para>
1607 <para>Change directory to
1608 <constant>$(FPTOOLS_TOP)</constant> and
1613 <indexterm><primary>autoreconf</primary></indexterm>
1614 (with no arguments). This GNU program converts
1615 <filename><constant>$(FPTOOLS_TOP)</constant>/configure.ac</filename>
1616 to a shell script called
1617 <filename><constant>$(FPTOOLS_TOP)</constant>/configure</filename>.
1618 If <command>autoreconf</command> bleats that it can't write the file <filename>configure</filename>,
1619 then delete the latter and try again. Note that you must use <command>autoreconf</command>,
1620 and not the old <command>autoconf</command>! If you erroneously use the latter, you'll get
1621 a message like "No rule to make target 'mk/config.h.in'".
1624 <para>Some projects, including GHC, have their own
1625 configure script. If there's an
1626 <constant>$(FPTOOLS_TOP)/<project>/configure.ac</constant>,
1627 then you need to run <command>autoreconf</command> in that
1628 directory too.</para>
1630 <para>These steps are completely
1631 platform-independent; they just mean that the
1632 human-written file (<filename>configure.ac</filename>) can
1633 be short, although the resulting shell script,
1634 <command>configure</command>, and
1635 <filename>mk/config.h.in</filename>, are long.</para>
1640 <term>Step 2: system configuration.</term>
1642 <para>Runs the newly-created <command>configure</command>
1643 script, thus:</para>
1646 ./configure <optional><parameter>args</parameter></optional>
1649 <para><command>configure</command>'s mission is to scurry
1650 round your computer working out what architecture it has,
1651 what operating system, whether it has the
1652 <Function>vfork</Function> system call, where
1653 <command>tar</command> is kept, whether
1654 <command>gcc</command> is available, where various obscure
1655 <literal>#include</literal> files are, whether it's a
1656 leap year, and what the systems manager had for lunch. It
1657 communicates these snippets of information in two
1664 <filename>mk/config.mk.in</filename><indexterm><primary>config.mk.in</primary></indexterm>
1666 <filename>mk/config.mk</filename><indexterm><primary>config.mk</primary></indexterm>,
1667 substituting for things between
1668 “<literal>@</literal>” brackets. So,
1669 “<literal>@HaveGcc@</literal>” will be
1670 replaced by “<literal>YES</literal>” or
1671 “<literal>NO</literal>” depending on what
1672 <command>configure</command> finds.
1673 <filename>mk/config.mk</filename> is included by every
1674 Makefile (directly or indirectly), so the
1675 configuration information is thereby communicated to
1676 all Makefiles.</para>
1680 <para> It translates
1681 <filename>mk/config.h.in</filename><indexterm><primary>config.h.in</primary></indexterm>
1683 <filename>mk/config.h</filename><indexterm><primary>config.h</primary></indexterm>.
1684 The latter is <literal>#include</literal>d by
1685 various C programs, which can thereby make use of
1686 configuration information.</para>
1690 <para><command>configure</command> takes some optional
1691 arguments. Use <literal>./configure --help</literal> to
1692 get a list of the available arguments. Here are some of
1693 the ones you might need:</para>
1697 <term><literal>--with-ghc=<parameter>path</parameter></literal></term>
1698 <indexterm><primary><literal>--with-ghc</literal></primary>
1701 <para>Specifies the path to an installed GHC which
1702 you would like to use. This compiler will be used
1703 for compiling GHC-specific code (eg. GHC itself).
1704 This option <emphasis>cannot</emphasis> be specified
1705 using <filename>build.mk</filename> (see later),
1706 because <command>configure</command> needs to
1707 auto-detect the version of GHC you're using. The
1708 default is to look for a compiler named
1709 <literal>ghc</literal> in your path.</para>
1714 <term><literal>--with-hc=<parameter>path</parameter></literal></term>
1715 <indexterm><primary><literal>--with-hc</literal></primary>
1718 <para>Specifies the path to any installed Haskell
1719 compiler. This compiler will be used for compiling
1720 generic Haskell code. The default is to use
1721 <literal>ghc</literal>.</para>
1726 <term><literal>--with-gcc=<parameter>path</parameter></literal></term>
1727 <indexterm><primary><literal>--with-gcc</literal></primary>
1730 <para>Specifies the path to the installed GCC. This
1731 compiler will be used to compile all C files,
1732 <emphasis>except</emphasis> any generated by the
1733 installed Haskell compiler, which will have its own
1734 idea of which C compiler (if any) to use. The
1735 default is to use <literal>gcc</literal>.</para>
1740 <para><command>configure</command> caches the results of
1741 its run in <filename>config.cache</filename>. Quite often
1742 you don't want that; you're running
1743 <command>configure</command> a second time because
1744 something has changed. In that case, simply delete
1745 <filename>config.cache</filename>.</para>
1750 <term>Step 3: build configuration.</term>
1752 <para>Next, you say how this build of
1753 <literal>fptools</literal> is to differ from the standard
1754 defaults by creating a new file
1755 <filename>mk/build.mk</filename><indexterm><primary>build.mk</primary></indexterm>
1756 <emphasis>in the build tree</emphasis>. This file is the
1757 one and only file you edit in the build tree, precisely
1758 because it says how this build differs from the source.
1759 (Just in case your build tree does die, you might want to
1760 keep a private directory of <filename>build.mk</filename>
1761 files, and use a symbolic link in each build tree to point
1762 to the appropriate one.) So
1763 <filename>mk/build.mk</filename> never exists in the
1764 source tree—you create one in each build tree from
1765 the template. We'll discuss what to put in it
1771 <para>And that's it for configuration. Simple, eh?</para>
1773 <para>What do you put in your build-specific configuration file
1774 <filename>mk/build.mk</filename>? <emphasis>For almost all
1775 purposes all you will do is put make variable definitions that
1776 override those in</emphasis>
1777 <filename>mk/config.mk.in</filename>. The whole point of
1778 <filename>mk/config.mk.in</filename>—and its derived
1779 counterpart <filename>mk/config.mk</filename>—is to define
1780 the build configuration. It is heavily commented, as you will
1781 see if you look at it. So generally, what you do is look at
1782 <filename>mk/config.mk.in</filename>, and add definitions in
1783 <filename>mk/build.mk</filename> that override any of the
1784 <filename>config.mk</filename> definitions that you want to
1785 change. (The override occurs because the main boilerplate file,
1786 <filename>mk/boilerplate.mk</filename><indexterm><primary>boilerplate.mk</primary></indexterm>,
1787 includes <filename>build.mk</filename> after
1788 <filename>config.mk</filename>.)</para>
1790 <para>For your convenience, there's a file called <filename>build.mk.sample</filename>
1791 that can serve as a starting point for your <filename>build.mk</filename>.</para>
1793 <para>For example, <filename>config.mk.in</filename> contains
1794 the definition:</para>
1797 GhcHcOpts=-O -Rghc-timing
1800 <para>The accompanying comment explains that this is the list of
1801 flags passed to GHC when building GHC itself. For doing
1802 development, it is wise to add <literal>-DDEBUG</literal>, to
1803 enable debugging code. So you would add the following to
1804 <filename>build.mk</filename>:</para>
1806 <para>or, if you prefer,</para>
1809 GhcHcOpts += -DDEBUG
1812 <para>GNU <command>make</command> allows existing definitions to
1813 have new text appended using the “<literal>+=</literal>”
1814 operator, which is quite a convenient feature.)</para>
1816 <para>If you want to remove the <literal>-O</literal> as well (a
1817 good idea when developing, because the turn-around cycle gets a
1818 lot quicker), you can just override
1819 <literal>GhcLibHcOpts</literal> altogether:</para>
1822 GhcHcOpts=-DDEBUG -Rghc-timing
1825 <para>When reading <filename>config.mk.in</filename>, remember
1826 that anything between “@...@” signs is going to be substituted
1827 by <command>configure</command> later. You
1828 <emphasis>can</emphasis> override the resulting definition if
1829 you want, but you need to be a bit surer what you are doing.
1830 For example, there's a line that says:</para>
1836 <para>This defines the Make variables <constant>TAR</constant>
1837 to the pathname for a <command>tar</command> that
1838 <command>configure</command> finds somewhere. If you have your
1839 own pet <command>tar</command> you want to use instead, that's
1840 fine. Just add this line to <filename>mk/build.mk</filename>:</para>
1846 <para>You do not <emphasis>have</emphasis> to have a
1847 <filename>mk/build.mk</filename> file at all; if you don't,
1848 you'll get all the default settings from
1849 <filename>mk/config.mk.in</filename>.</para>
1851 <para>You can also use <filename>build.mk</filename> to override
1852 anything that <command>configure</command> got wrong. One place
1853 where this happens often is with the definition of
1854 <constant>FPTOOLS_TOP_ABS</constant>: this
1855 variable is supposed to be the canonical path to the top of your
1856 source tree, but if your system uses an automounter then the
1857 correct directory is hard to find automatically. If you find
1858 that <command>configure</command> has got it wrong, just put the
1859 correct definition in <filename>build.mk</filename>.</para>
1863 <sect2 id="sec-storysofar">
1864 <title>The story so far</title>
1866 <para>Let's summarise the steps you need to carry to get
1867 yourself a fully-configured build tree from scratch.</para>
1871 <para> Get your source tree from somewhere (CVS repository
1872 or source distribution). Say you call the root directory
1873 <filename>myfptools</filename> (it does not have to be
1874 called <filename>fptools</filename>). Make sure that you
1875 have the essential files (see <XRef
1876 LinkEnd="sec-source-tree">).</para>
1881 <para>(Optional) Use <command>lndir</command> or
1882 <command>mkshadowdir</command> to create a build tree.</para>
1886 $ mkshadowdir . /scratch/joe-bloggs/myfptools-sun4
1889 <para>(N.B. <command>mkshadowdir</command>'s first argument
1890 is taken relative to its second.) You probably want to give
1891 the build tree a name that suggests its main defining
1892 characteristic (in your mind at least), in case you later
1897 <para>Change directory to the build tree. Everything is
1898 going to happen there now.</para>
1901 $ cd /scratch/joe-bloggs/myfptools-sun4
1907 <para>Prepare for system configuration:</para>
1913 <para>(You can skip this step if you are starting from a
1914 source distribution, and you already have
1915 <filename>configure</filename> and
1916 <filename>mk/config.h.in</filename>.)</para>
1918 <para>Some projects, including GHC itself, have their own
1919 configure scripts, so it is necessary to run autoreconf again
1920 in the appropriate subdirectories. eg:</para>
1923 $ (cd ghc; autoreconf)
1928 <para>Do system configuration:</para>
1934 <para>Don't forget to check whether you need to add any
1935 arguments to <literal>configure</literal>; for example, a
1936 common requirement is to specify which GHC to use with
1937 <option>--with-ghc=<replaceable>ghc</replaceable></option>.</para>
1941 <para>Create the file <filename>mk/build.mk</filename>,
1942 adding definitions for your desired configuration
1951 <para>You can make subsequent changes to
1952 <filename>mk/build.mk</filename> as often as you like. You do
1953 not have to run any further configuration programs to make these
1954 changes take effect. In theory you should, however, say
1955 <command>gmake clean</command>, <command>gmake all</command>,
1956 because configuration option changes could affect
1957 anything—but in practice you are likely to know what's
1962 <title>Making things</title>
1964 <para>At this point you have made yourself a fully-configured
1965 build tree, so you are ready to start building real
1968 <para>The first thing you need to know is that <emphasis>you
1969 must use GNU <command>make</command>, usually called
1970 <command>gmake</command>, not standard Unix
1971 <command>make</command></emphasis>. If you use standard Unix
1972 <command>make</command> you will get all sorts of error messages
1973 (but no damage) because the <literal>fptools</literal>
1974 <command>Makefiles</command> use GNU <command>make</command>'s
1975 facilities extensively.</para>
1977 <para>To just build the whole thing, <command>cd</command> to
1978 the top of your <literal>fptools</literal> tree and type
1979 <command>gmake</command>. This will prepare the tree and build
1980 the various projects in the correct order.</para>
1983 <sect2 id="sec-bootstrapping">
1984 <title>Bootstrapping GHC</title>
1986 <para>GHC requires a 2-stage bootstrap in order to provide
1987 full functionality, including GHCi. By a 2-stage bootstrap, we
1988 mean that the compiler is built once using the installed GHC,
1989 and then again using the compiler built in the first stage. You
1990 can also build a stage 3 compiler, but this normally isn't
1991 necessary except to verify that the stage 2 compiler is working
1994 <para>Note that when doing a bootstrap, the stage 1 compiler
1995 must be built, followed by the runtime system and libraries, and
1996 then the stage 2 compiler. The correct ordering is implemented
1997 by the top-level fptools <filename>Makefile</filename>, so if
1998 you want everything to work automatically it's best to start
1999 <command>make</command> from the top of the tree. When building
2000 GHC, the top-level fptools <filename>Makefile</filename> is set
2001 up to do a 2-stage bootstrap by default (when you say
2002 <command>make</command>). Some other targets it supports
2009 <para>Build everything as normal, including the stage 1
2017 <para>Build the stage 2 compiler only.</para>
2024 <para>Build the stage 3 compiler only.</para>
2029 <term>bootstrap</term> <term>bootstrap2</term>
2031 <para>Build stage 1 followed by stage 2.</para>
2036 <term>bootstrap3</term>
2038 <para>Build stages 1, 2 and 3.</para>
2043 <term>install</term>
2045 <para>Install everything, including the compiler built in
2046 stage 2. To override the stage, say <literal>make install
2047 stage=<replaceable>n</replaceable></literal> where
2048 <replaceable>n</replaceable> is the stage to install.</para>
2053 <para>The top-level <filename>Makefile</filename> also arranges
2054 to do the appropriate <literal>make boot</literal> steps (see
2055 below) before actually building anything.</para>
2057 <para>The <literal>stage1</literal>, <literal>stage2</literal>
2058 and <literal>stage3</literal> targets also work in the
2059 <literal>ghc/compiler</literal> directory, but don't forget that
2060 each stage requires its own <literal>make boot</literal> step:
2061 for example, you must do</para>
2063 <screen>$ make boot stage=2</screen>
2065 <para>before <literal>make stage2</literal> in
2066 <literal>ghc/compiler</literal>.</para>
2069 <sect2 id="sec-standard-targets">
2070 <title>Standard Targets</title>
2071 <indexterm><primary>targets, standard makefile</primary></indexterm>
2072 <indexterm><primary>makefile targets</primary></indexterm>
2074 <para>In any directory you should be able to make the following:</para>
2078 <term><literal>boot</literal></term>
2080 <para>does the one-off preparation required to get ready
2081 for the real work. Notably, it does <command>gmake
2082 depend</command> in all directories that contain programs.
2083 It also builds the necessary tools for compilation to
2086 <para>Invoking the <literal>boot</literal> target
2087 explicitly is not normally necessary. From the top-level
2088 <literal>fptools</literal> directory, invoking
2089 <literal>gmake</literal> causes <literal>gmake boot
2090 all</literal> to be invoked in each of the project
2091 subdirectories, in the order specified by
2092 <literal>$(AllTargets)</literal> in
2093 <literal>config.mk</literal>.</para>
2095 <para>If you're working in a subdirectory somewhere and
2096 need to update the dependencies, <literal>gmake
2097 boot</literal> is a good way to do it.</para>
2102 <term><literal>all</literal></term>
2104 <para>makes all the final target(s) for this Makefile.
2105 Depending on which directory you are in a “final
2106 target” may be an executable program, a library
2107 archive, a shell script, or a Postscript file. Typing
2108 <command>gmake</command> alone is generally the same as
2109 typing <command>gmake all</command>.</para>
2114 <term><literal>install</literal></term>
2116 <para>installs the things built by <literal>all</literal>
2117 (except for the documentation). Where does it install
2118 them? That is specified by
2119 <filename>mk/config.mk.in</filename>; you can override it
2120 in <filename>mk/build.mk</filename>, or by running
2121 <command>configure</command> with command-line arguments
2122 like <literal>--bindir=/home/simonpj/bin</literal>; see
2123 <literal>./configure --help</literal> for the full
2129 <term><literal>install-docs</literal></term>
2131 <para>installs the documentation. Otherwise behaves just
2132 like <literal>install</literal>.</para>
2137 <term><literal>uninstall</literal></term>
2139 <para>reverses the effect of
2140 <literal>install</literal>.</para>
2145 <term><literal>clean</literal></term>
2147 <para>Delete all files from the current directory that are
2148 normally created by building the program. Don't delete
2149 the files that record the configuration, or files
2150 generated by <command>gmake boot</command>. Also preserve
2151 files that could be made by building, but normally aren't
2152 because the distribution comes with them.</para>
2157 <term><literal>distclean</literal></term>
2159 <para>Delete all files from the current directory that are
2160 created by configuring or building the program. If you
2161 have unpacked the source and built the program without
2162 creating any other files, <literal>make
2163 distclean</literal> should leave only the files that were
2164 in the distribution.</para>
2169 <term><literal>mostlyclean</literal></term>
2171 <para>Like <literal>clean</literal>, but may refrain from
2172 deleting a few files that people normally don't want to
2178 <term><literal>maintainer-clean</literal></term>
2180 <para>Delete everything from the current directory that
2181 can be reconstructed with this Makefile. This typically
2182 includes everything deleted by
2183 <literal>distclean</literal>, plus more: C source files
2184 produced by Bison, tags tables, Info files, and so
2187 <para>One exception, however: <literal>make
2188 maintainer-clean</literal> should not delete
2189 <filename>configure</filename> even if
2190 <filename>configure</filename> can be remade using a rule
2191 in the <filename>Makefile</filename>. More generally,
2192 <literal>make maintainer-clean</literal> should not delete
2193 anything that needs to exist in order to run
2194 <filename>configure</filename> and then begin to build the
2200 <term><literal>check</literal></term>
2202 <para>run the test suite.</para>
2207 <para>All of these standard targets automatically recurse into
2208 sub-directories. Certain other standard targets do not:</para>
2212 <term><literal>configure</literal></term>
2214 <para>is only available in the root directory
2215 <constant>$(FPTOOLS_TOP)</constant>; it has
2216 been discussed in <XRef
2217 LinkEnd="sec-build-config">.</para>
2222 <term><literal>depend</literal></term>
2224 <para>make a <filename>.depend</filename> file in each
2225 directory that needs it. This <filename>.depend</filename>
2226 file contains mechanically-generated dependency
2227 information; for example, suppose a directory contains a
2228 Haskell source module <filename>Foo.lhs</filename> which
2229 imports another module <literal>Baz</literal>. Then the
2230 generated <filename>.depend</filename> file will contain
2231 the dependency:</para>
2237 <para>which says that the object file
2238 <filename>Foo.o</filename> depends on the interface file
2239 <filename>Baz.hi</filename> generated by compiling module
2240 <literal>Baz</literal>. The <filename>.depend</filename>
2241 file is automatically included by every Makefile.</para>
2246 <term><literal>binary-dist</literal></term>
2248 <para>make a binary distribution. This is the target we
2249 use to build the binary distributions of GHC and
2255 <term><literal>dist</literal></term>
2257 <para>make a source distribution. Note that this target
2258 does “make distclean” as part of its work;
2259 don't use it if you want to keep what you've built.</para>
2264 <para>Most <filename>Makefile</filename>s have targets other
2265 than these. You can discover them by looking in the
2266 <filename>Makefile</filename> itself.</para>
2270 <title>Using a project from the build tree</title>
2272 <para>If you want to build GHC (say) and just use it direct from
2273 the build tree without doing <literal>make install</literal>
2274 first, you can run the in-place driver script:
2275 <filename>ghc/compiler/ghc-inplace</filename>.</para>
2277 <para> Do <emphasis>NOT</emphasis> use
2278 <filename>ghc/compiler/ghc</filename>, or
2279 <filename>ghc/compiler/ghc-6.xx</filename>, as these are the
2280 scripts intended for installation, and contain hard-wired paths
2281 to the installed libraries, rather than the libraries in the
2284 <para>Happy can similarly be run from the build tree, using
2285 <filename>happy/src/happy-inplace</filename>, and similarly for
2286 Alex and Haddock.</para>
2290 <title>Fast Making</title>
2292 <indexterm><primary>fastmake</primary></indexterm>
2293 <indexterm><primary>dependencies, omitting</primary></indexterm>
2294 <indexterm><primary>FAST, makefile variable</primary></indexterm>
2296 <para>Sometimes the dependencies get in the way: if you've made
2297 a small change to one file, and you're absolutely sure that it
2298 won't affect anything else, but you know that
2299 <command>make</command> is going to rebuild everything anyway,
2300 the following hack may be useful:</para>
2306 <para>This tells the make system to ignore dependencies and just
2307 build what you tell it to. In other words, it's equivalent to
2308 temporarily removing the <filename>.depend</filename> file in
2309 the current directory (where <command>mkdependHS</command> and
2310 friends store their dependency information).</para>
2312 <para>A bit of history: GHC used to come with a
2313 <command>fastmake</command> script that did the above job, but
2314 GNU make provides the features we need to do it without
2315 resorting to a script. Also, we've found that fastmaking is
2316 less useful since the advent of GHC's recompilation checker (see
2317 the User's Guide section on "Separate Compilation").</para>
2321 <sect1 id="sec-makefile-arch">
2322 <title>The <filename>Makefile</filename> architecture</title>
2323 <indexterm><primary>makefile architecture</primary></indexterm>
2325 <para><command>make</command> is great if everything
2326 works—you type <command>gmake install</command> and lo! the
2327 right things get compiled and installed in the right places. Our
2328 goal is to make this happen often, but somehow it often doesn't;
2329 instead some weird error message eventually emerges from the
2330 bowels of a directory you didn't know existed.</para>
2332 <para>The purpose of this section is to give you a road-map to
2333 help you figure out what is going right and what is going
2337 <title>Debugging</title>
2339 <para>Debugging <filename>Makefile</filename>s is something of a
2340 black art, but here's a couple of tricks that we find
2341 particularly useful. The following command allows you to see
2342 the contents of any make variable in the context of the current
2343 <filename>Makefile</filename>:</para>
2345 <screen>$ make show VALUE=HS_SRCS</screen>
2347 <para>where you can replace <literal>HS_SRCS</literal> with the
2348 name of any variable you wish to see the value of.</para>
2350 <para>GNU make has a <option>-d</option> option which generates
2351 a dump of the decision procedure used to arrive at a conclusion
2352 about which files should be recompiled. Sometimes useful for
2353 tracking down problems with superfluous or missing
2354 recompilations.</para>
2358 <title>A small project</title>
2360 <para>To get started, let us look at the
2361 <filename>Makefile</filename> for an imaginary small
2362 <literal>fptools</literal> project, <literal>small</literal>.
2363 Each project in <literal>fptools</literal> has its own directory
2364 in <constant>FPTOOLS_TOP</constant>, so the
2365 <literal>small</literal> project will have its own directory
2366 <constant>FPOOLS_TOP/small/</constant>. Inside the
2367 <filename>small/</filename> directory there will be a
2368 <filename>Makefile</filename>, looking something like
2371 <indexterm><primary>Makefile, minimal</primary></indexterm>
2374 # Makefile for fptools project "small"
2377 include $(TOP)/mk/boilerplate.mk
2379 SRCS = $(wildcard *.lhs) $(wildcard *.c)
2382 include $(TOP)/target.mk
2385 <para>this <filename>Makefile</filename> has three
2390 <para>The first section includes
2393 One of the most important
2394 features of GNU <command>make</command> that we use is the ability for a <filename>Makefile</filename> to
2395 include another named file, very like <command>cpp</command>'s <literal>#include</literal>
2400 a file of “boilerplate” code from the level
2401 above (which in this case will be
2402 <filename><constant>FPTOOLS_TOP</constant>/mk/boilerplate.mk</filename><indexterm><primary>boilerplate.mk</primary></indexterm>).
2403 As its name suggests, <filename>boilerplate.mk</filename>
2404 consists of a large quantity of standard
2405 <filename>Makefile</filename> code. We discuss this
2406 boilerplate in more detail in <XRef LinkEnd="sec-boiler">.
2407 <indexterm><primary>include, directive in
2408 Makefiles</primary></indexterm> <indexterm><primary>Makefile
2409 inclusion</primary></indexterm></para>
2411 <para>Before the <literal>include</literal> statement, you
2412 must define the <command>make</command> variable
2413 <constant>TOP</constant><indexterm><primary>TOP</primary></indexterm>
2414 to be the directory containing the <filename>mk</filename>
2415 directory in which the <filename>boilerplate.mk</filename>
2416 file is. It is <emphasis>not</emphasis> OK to simply say</para>
2419 include ../mk/boilerplate.mk # NO NO NO
2423 <para>Why? Because the <filename>boilerplate.mk</filename>
2424 file needs to know where it is, so that it can, in turn,
2425 <literal>include</literal> other files. (Unfortunately,
2426 when an <literal>include</literal>d file does an
2427 <literal>include</literal>, the filename is treated relative
2428 to the directory in which <command>gmake</command> is being
2429 run, not the directory in which the
2430 <literal>include</literal>d sits.) In general,
2431 <emphasis>every file <filename>foo.mk</filename> assumes
2433 <filename><constant>$(TOP)</constant>/mk/foo.mk</filename>
2434 refers to itself.</emphasis> It is up to the
2435 <filename>Makefile</filename> doing the
2436 <literal>include</literal> to ensure this is the case.</para>
2438 <para>Files intended for inclusion in other
2439 <filename>Makefile</filename>s are written to have the
2440 following property: <emphasis>after
2441 <filename>foo.mk</filename> is <literal>include</literal>d,
2442 it leaves <constant>TOP</constant> containing the same value
2443 as it had just before the <literal>include</literal>
2444 statement</emphasis>. In our example, this invariant
2445 guarantees that the <literal>include</literal> for
2446 <filename>target.mk</filename> will look in the same
2447 directory as that for <filename>boilerplate.mk</filename>.</para>
2451 <para> The second section defines the following standard
2452 <command>make</command> variables:
2453 <constant>SRCS</constant><indexterm><primary>SRCS</primary></indexterm>
2454 (the source files from which is to be built), and
2455 <constant>HS_PROG</constant><indexterm><primary>HS_PROG</primary></indexterm>
2456 (the executable binary to be built). We will discuss in
2457 more detail what the “standard variables” are,
2458 and how they affect what happens, in <XRef
2459 LinkEnd="sec-targets">.</para>
2461 <para>The definition for <constant>SRCS</constant> uses the
2462 useful GNU <command>make</command> construct
2463 <literal>$(wildcard $pat$)</literal><indexterm><primary>wildcard</primary></indexterm>,
2464 which expands to a list of all the files matching the
2465 pattern <literal>pat</literal> in the current directory. In
2466 this example, <constant>SRCS</constant> is set to the list
2467 of all the <filename>.lhs</filename> and
2468 <filename>.c</filename> files in the directory. (Let's
2469 suppose there is one of each, <filename>Foo.lhs</filename>
2470 and <filename>Baz.c</filename>.)</para>
2474 <para>The last section includes a second file of standard
2476 <filename>target.mk</filename><indexterm><primary>target.mk</primary></indexterm>.
2477 It contains the rules that tell <command>gmake</command> how
2478 to make the standard targets (<Xref
2479 LinkEnd="sec-standard-targets">). Why, you ask, can't this
2480 standard code be part of
2481 <filename>boilerplate.mk</filename>? Good question. We
2482 discuss the reason later, in <Xref
2483 LinkEnd="sec-boiler-arch">.</para>
2485 <para>You do not <emphasis>have</emphasis> to
2486 <literal>include</literal> the
2487 <filename>target.mk</filename> file. Instead, you can write
2488 rules of your own for all the standard targets. Usually,
2489 though, you will find quite a big payoff from using the
2490 canned rules in <filename>target.mk</filename>; the price
2491 tag is that you have to understand what canned rules get
2492 enabled, and what they do (<Xref
2493 LinkEnd="sec-targets">).</para>
2497 <para>In our example <filename>Makefile</filename>, most of the
2498 work is done by the two <literal>include</literal>d files. When
2499 you say <command>gmake all</command>, the following things
2504 <para><command>gmake</command> figures out that the object
2505 files are <filename>Foo.o</filename> and
2506 <filename>Baz.o</filename>.</para>
2510 <para>It uses a boilerplate pattern rule to compile
2511 <filename>Foo.lhs</filename> to <filename>Foo.o</filename>
2512 using a Haskell compiler. (Which one? That is set in the
2513 build configuration.)</para>
2517 <para>It uses another standard pattern rule to compile
2518 <filename>Baz.c</filename> to <filename>Baz.o</filename>,
2519 using a C compiler. (Ditto.)</para>
2523 <para>It links the resulting <filename>.o</filename> files
2524 together to make <literal>small</literal>, using the Haskell
2525 compiler to do the link step. (Why not use
2526 <command>ld</command>? Because the Haskell compiler knows
2527 what standard libraries to link in. How did
2528 <command>gmake</command> know to use the Haskell compiler to
2529 do the link, rather than the C compiler? Because we set the
2530 variable <constant>HS_PROG</constant> rather than
2531 <constant>C_PROG</constant>.)</para>
2535 <para>All <filename>Makefile</filename>s should follow the above
2536 three-section format.</para>
2540 <title>A larger project</title>
2542 <para>Larger projects are usually structured into a number of
2543 sub-directories, each of which has its own
2544 <filename>Makefile</filename>. (In very large projects, this
2545 sub-structure might be iterated recursively, though that is
2546 rare.) To give you the idea, here's part of the directory
2547 structure for the (rather large) GHC project:</para>
2557 ...source files for documentation...
2560 ...source files for driver...
2563 parser/...source files for parser...
2564 renamer/...source files for renamer...
2568 <para>The sub-directories <filename>docs</filename>,
2569 <filename>driver</filename>, <filename>compiler</filename>, and
2570 so on, each contains a sub-component of GHC, and each has its
2571 own <filename>Makefile</filename>. There must also be a
2572 <filename>Makefile</filename> in
2573 <filename><constant>$(FPTOOLS_TOP)</constant>/ghc</filename>.
2574 It does most of its work by recursively invoking
2575 <command>gmake</command> on the <filename>Makefile</filename>s
2576 in the sub-directories. We say that
2577 <filename>ghc/Makefile</filename> is a <emphasis>non-leaf
2578 <filename>Makefile</filename></emphasis>, because it does little
2579 except organise its children, while the
2580 <filename>Makefile</filename>s in the sub-directories are all
2581 <emphasis>leaf <filename>Makefile</filename>s</emphasis>. (In
2582 principle the sub-directories might themselves contain a
2583 non-leaf <filename>Makefile</filename> and several
2584 sub-sub-directories, but that does not happen in GHC.)</para>
2586 <para>The <filename>Makefile</filename> in
2587 <filename>ghc/compiler</filename> is considered a leaf
2588 <filename>Makefile</filename> even though the
2589 <filename>ghc/compiler</filename> has sub-directories, because
2590 these sub-directories do not themselves have
2591 <filename>Makefile</filename>s in them. They are just used to
2592 structure the collection of modules that make up GHC, but all
2593 are managed by the single <filename>Makefile</filename> in
2594 <filename>ghc/compiler</filename>.</para>
2596 <para>You will notice that <filename>ghc/</filename> also
2597 contains a directory <filename>ghc/mk/</filename>. It contains
2598 GHC-specific <filename>Makefile</filename> boilerplate code.
2599 More precisely:</para>
2603 <para><filename>ghc/mk/boilerplate.mk</filename> is included
2604 at the top of <filename>ghc/Makefile</filename>, and of all
2605 the leaf <filename>Makefile</filename>s in the
2606 sub-directories. It in turn <literal>include</literal>s the
2607 main boilerplate file
2608 <filename>mk/boilerplate.mk</filename>.</para>
2612 <para><filename>ghc/mk/target.mk</filename> is
2613 <literal>include</literal>d at the bottom of
2614 <filename>ghc/Makefile</filename>, and of all the leaf
2615 <filename>Makefile</filename>s in the sub-directories. It
2616 in turn <literal>include</literal>s the file
2617 <filename>mk/target.mk</filename>.</para>
2621 <para>So these two files are the place to look for GHC-wide
2622 customisation of the standard boilerplate.</para>
2625 <sect2 id="sec-boiler-arch">
2626 <title>Boilerplate architecture</title>
2627 <indexterm><primary>boilerplate architecture</primary></indexterm>
2629 <para>Every <filename>Makefile</filename> includes a
2630 <filename>boilerplate.mk</filename><indexterm><primary>boilerplate.mk</primary></indexterm>
2631 file at the top, and
2632 <filename>target.mk</filename><indexterm><primary>target.mk</primary></indexterm>
2633 file at the bottom. In this section we discuss what is in these
2634 files, and why there have to be two of them. In general:</para>
2638 <para><filename>boilerplate.mk</filename> consists of:</para>
2642 <para><emphasis>Definitions of millions of
2643 <command>make</command> variables</emphasis> that
2644 collectively specify the build configuration. Examples:
2645 <constant>HC_OPTS</constant><indexterm><primary>HC_OPTS</primary></indexterm>,
2646 the options to feed to the Haskell compiler;
2647 <constant>NoFibSubDirs</constant><indexterm><primary>NoFibSubDirs</primary></indexterm>,
2648 the sub-directories to enable within the
2649 <literal>nofib</literal> project;
2650 <constant>GhcWithHc</constant><indexterm><primary>GhcWithHc</primary></indexterm>,
2651 the name of the Haskell compiler to use when compiling
2652 GHC in the <literal>ghc</literal> project.</para>
2656 <para><emphasis>Standard pattern rules</emphasis> that
2657 tell <command>gmake</command> how to construct one file
2658 from another.</para>
2662 <para><filename>boilerplate.mk</filename> needs to be
2663 <literal>include</literal>d at the <emphasis>top</emphasis>
2664 of each <filename>Makefile</filename>, so that the user can
2665 replace the boilerplate definitions or pattern rules by
2666 simply giving a new definition or pattern rule in the
2667 <filename>Makefile</filename>. <command>gmake</command>
2668 simply takes the last definition as the definitive one.</para>
2670 <para>Instead of <emphasis>replacing</emphasis> boilerplate
2671 definitions, it is also quite common to
2672 <emphasis>augment</emphasis> them. For example, a
2673 <filename>Makefile</filename> might say:</para>
2679 <para>thereby adding “<option>-O</option>” to
2681 <constant>SRC_HC_OPTS</constant><indexterm><primary>SRC_HC_OPTS</primary></indexterm>.</para>
2685 <para><filename>target.mk</filename> contains
2686 <command>make</command> rules for the standard targets
2687 described in <Xref LinkEnd="sec-standard-targets">. These
2688 rules are selectively included, depending on the setting of
2689 certain <command>make</command> variables. These variables
2690 are usually set in the middle section of the
2691 <filename>Makefile</filename> between the two
2692 <literal>include</literal>s.</para>
2694 <para><filename>target.mk</filename> must be included at the
2695 end (rather than being part of
2696 <filename>boilerplate.mk</filename>) for several tiresome
2702 <para><command>gmake</command> commits target and
2703 dependency lists earlier than it should. For example,
2704 <FIlename>target.mk</FIlename> has a rule that looks
2708 $(HS_PROG) : $(OBJS)
2709 $(HC) $(LD_OPTS) $< -o $@
2712 <para>If this rule was in
2713 <filename>boilerplate.mk</filename> then
2714 <constant>$(HS_PROG)</constant><indexterm><primary>HS_PROG</primary></indexterm>
2716 <constant>$(OBJS)</constant><indexterm><primary>OBJS</primary></indexterm>
2717 would not have their final values at the moment
2718 <command>gmake</command> encountered the rule. Alas,
2719 <command>gmake</command> takes a snapshot of their
2720 current values, and wires that snapshot into the rule.
2721 (In contrast, the commands executed when the rule
2722 “fires” are only substituted at the moment
2723 of firing.) So, the rule must follow the definitions
2724 given in the <filename>Makefile</filename> itself.</para>
2728 <para>Unlike pattern rules, ordinary rules cannot be
2729 overriden or replaced by subsequent rules for the same
2730 target (at least, not without an error message).
2731 Including ordinary rules in
2732 <filename>boilerplate.mk</filename> would prevent the
2733 user from writing rules for specific targets in specific
2738 <para>There are a couple of other reasons I've
2739 forgotten, but it doesn't matter too much.</para>
2746 <sect2 id="sec-boiler">
2747 <title>The main <filename>mk/boilerplate.mk</filename> file</title>
2748 <indexterm><primary>boilerplate.mk</primary></indexterm>
2750 <para>If you look at
2751 <filename><constant>$(FPTOOLS_TOP)</constant>/mk/boilerplate.mk</filename>
2752 you will find that it consists of the following sections, each
2753 held in a separate file:</para>
2757 <term><filename>config.mk</filename></term>
2758 <indexterm><primary>config.mk</primary></indexterm>
2760 <para>is the build configuration file we discussed at
2761 length in <Xref LinkEnd="sec-build-config">.</para>
2766 <term><filename>paths.mk</filename></term>
2767 <indexterm><primary>paths.mk</primary></indexterm>
2769 <para>defines <command>make</command> variables for
2770 pathnames and file lists. This file contains code for
2771 automatically compiling lists of source files and deriving
2772 lists of object files from those. The results can be
2773 overriden in the <filename>Makefile</filename>, but in
2774 most cases the automatic setup should do the right
2777 <para>The following variables may be set in the
2778 <filename>Makefile</filename> to affect how the automatic
2779 source file search is done:</para>
2783 <term><literal>ALL_DIRS</literal></term>
2784 <indexterm><primary><literal>ALL_DIRS</literal></primary>
2787 <para>Set to a list of directories to search in
2788 addition to the current directory for source
2794 <term><literal>EXCLUDE_SRCS</literal></term>
2795 <indexterm><primary><literal>EXCLUDE_SRCS</literal></primary>
2798 <para>Set to a list of source files (relative to the
2799 current directory) to omit from the automatic
2800 search. The source searching machinery is clever
2801 enough to know that if you exclude a source file
2802 from which other sources are derived, then the
2803 derived sources should also be excluded. For
2804 example, if you set <literal>EXCLUDED_SRCS</literal>
2805 to include <filename>Foo.y</filename>, then
2806 <filename>Foo.hs</filename> will also be
2812 <term><literal>EXTRA_SRCS</literal></term>
2813 <indexterm><primary><literal>EXCLUDE_SRCS</literal></primary>
2816 <para>Set to a list of extra source files (perhaps
2817 in directories not listed in
2818 <literal>ALL_DIRS</literal>) that should be
2824 <para>The results of the automatic source file search are
2825 placed in the following make variables:</para>
2829 <term><literal>SRCS</literal></term>
2830 <indexterm><primary><literal>SRCS</literal></primary></indexterm>
2832 <para>All source files found, sorted and without
2833 duplicates, including those which might not exist
2834 yet but will be derived from other existing sources.
2835 <literal>SRCS</literal> <emphasis>can</emphasis> be
2836 overriden if necessary, in which case the variables
2837 below will follow suit.</para>
2842 <term><literal>HS_SRCS</literal></term>
2843 <indexterm><primary><literal>HS_SRCS</literal></primary></indexterm>
2845 <para>all Haskell source files in the current
2846 directory, including those derived from other source
2847 files (eg. Happy sources also give rise to Haskell
2853 <term><literal>HS_OBJS</literal></term>
2854 <indexterm><primary><literal>HS_OBJS</literal></primary></indexterm>
2856 <para>Object files derived from
2857 <literal>HS_SRCS</literal>.</para>
2862 <term><literal>HS_IFACES</literal></term>
2863 <indexterm><primary><literal>HS_IFACES</literal></primary></indexterm>
2865 <para>Interface files (<literal>.hi</literal> files)
2866 derived from <literal>HS_SRCS</literal>.</para>
2871 <term><literal>C_SRCS</literal></term>
2872 <indexterm><primary><literal>C_SRCS</literal></primary></indexterm>
2874 <para>All C source files found.</para>
2879 <term><literal>C_OBJS</literal></term>
2880 <indexterm><primary><literal>C_OBJS</literal></primary></indexterm>
2882 <para>Object files derived from
2883 <literal>C_SRCS</literal>.</para>
2888 <term><literal>SCRIPT_SRCS</literal></term>
2889 <indexterm><primary><literal>SCRIPT_SRCS</literal></primary></indexterm>
2891 <para>All script source files found
2892 (<literal>.lprl</literal> files).</para>
2897 <term><literal>SCRIPT_OBJS</literal></term>
2898 <indexterm><primary><literal>SCRIPT_OBJS</literal></primary></indexterm>
2900 <para><quote>object</quote> files derived from
2901 <literal>SCRIPT_SRCS</literal>
2902 (<literal>.prl</literal> files).</para>
2907 <term><literal>HSC_SRCS</literal></term>
2908 <indexterm><primary><literal>HSC_SRCS</literal></primary></indexterm>
2910 <para>All <literal>hsc2hs</literal> source files
2911 (<literal>.hsc</literal> files).</para>
2916 <term><literal>HAPPY_SRCS</literal></term>
2917 <indexterm><primary><literal>HAPPY_SRCS</literal></primary></indexterm>
2919 <para>All <literal>happy</literal> source files
2920 (<literal>.y</literal> or <literal>.hy</literal> files).</para>
2925 <term><literal>OBJS</literal></term>
2926 <indexterm><primary>OBJS</primary></indexterm>
2928 <para>the concatenation of
2929 <literal>$(HS_OBJS)</literal>,
2930 <literal>$(C_OBJS)</literal>, and
2931 <literal>$(SCRIPT_OBJS)</literal>.</para>
2936 <para>Any or all of these definitions can easily be
2937 overriden by giving new definitions in your
2938 <filename>Makefile</filename>.</para>
2940 <para>What, exactly, does <filename>paths.mk</filename>
2941 consider a <quote>source file</quote> to be? It's based
2942 on the file's suffix (e.g. <filename>.hs</filename>,
2943 <filename>.lhs</filename>, <filename>.c</filename>,
2944 <filename>.hy</filename>, etc), but this is the kind of
2945 detail that changes, so rather than enumerate the source
2946 suffices here the best thing to do is to look in
2947 <filename>paths.mk</filename>.</para>
2952 <term><filename>opts.mk</filename></term>
2953 <indexterm><primary>opts.mk</primary></indexterm>
2955 <para>defines <command>make</command> variables for option
2956 strings to pass to each program. For example, it defines
2957 <constant>HC_OPTS</constant><indexterm><primary>HC_OPTS</primary></indexterm>,
2958 the option strings to pass to the Haskell compiler. See
2959 <Xref LinkEnd="sec-suffix">.</para>
2964 <term><filename>suffix.mk</filename></term>
2965 <indexterm><primary>suffix.mk</primary></indexterm>
2967 <para>defines standard pattern rules—see <Xref
2968 LinkEnd="sec-suffix">.</para>
2973 <para>Any of the variables and pattern rules defined by the
2974 boilerplate file can easily be overridden in any particular
2975 <filename>Makefile</filename>, because the boilerplate
2976 <literal>include</literal> comes first. Definitions after this
2977 <literal>include</literal> directive simply override the default
2978 ones in <filename>boilerplate.mk</filename>.</para>
2981 <sect2 id="sec-suffix">
2982 <title>Pattern rules and options</title>
2983 <indexterm><primary>Pattern rules</primary></indexterm>
2986 <filename>suffix.mk</filename><indexterm><primary>suffix.mk</primary></indexterm>
2987 defines standard <emphasis>pattern rules</emphasis> that say how
2988 to build one kind of file from another, for example, how to
2989 build a <filename>.o</filename> file from a
2990 <filename>.c</filename> file. (GNU <command>make</command>'s
2991 <emphasis>pattern rules</emphasis> are more powerful and easier
2992 to use than Unix <command>make</command>'s <emphasis>suffix
2993 rules</emphasis>.)</para>
2995 <para>Almost all the rules look something like this:</para>
3000 $(CC) $(CC_OPTS) -c $< -o $@
3003 <para>Here's how to understand the rule. It says that
3004 <emphasis>something</emphasis><filename>.o</filename> (say
3005 <filename>Foo.o</filename>) can be built from
3006 <emphasis>something</emphasis><filename>.c</filename>
3007 (<filename>Foo.c</filename>), by invoking the C compiler (path
3008 name held in <constant>$(CC)</constant>), passing to it
3009 the options <constant>$(CC_OPTS)</constant> and
3010 the rule's dependent file of the rule
3011 <literal>$<</literal> (<filename>Foo.c</filename> in
3012 this case), and putting the result in the rule's target
3013 <literal>$@</literal> (<filename>Foo.o</filename> in this
3016 <para>Every program is held in a <command>make</command>
3017 variable defined in <filename>mk/config.mk</filename>—look
3018 in <filename>mk/config.mk</filename> for the complete list. One
3019 important one is the Haskell compiler, which is called
3020 <constant>$(HC)</constant>.</para>
3022 <para>Every program's options are are held in a
3023 <command>make</command> variables called
3024 <constant><prog>_OPTS</constant>. the
3025 <constant><prog>_OPTS</constant> variables are
3026 defined in <filename>mk/opts.mk</filename>. Almost all of them
3027 are defined like this:</para>
3030 CC_OPTS = $(SRC_CC_OPTS) $(WAY$(_way)_CC_OPTS) $($*_CC_OPTS) $(EXTRA_CC_OPTS)
3033 <para>The four variables from which
3034 <constant>CC_OPTS</constant> is built have the following
3039 <term><constant>SRC_CC_OPTS</constant><indexterm><primary>SRC_CC_OPTS</primary></indexterm>:</term>
3041 <para>options passed to all C compilations.</para>
3046 <term><constant>WAY_<way>_CC_OPTS</constant>:</term>
3048 <para>options passed to C compilations for way
3049 <literal><way></literal>. For example,
3050 <constant>WAY_mp_CC_OPTS</constant>
3051 gives options to pass to the C compiler when compiling way
3052 <literal>mp</literal>. The variable
3053 <constant>WAY_CC_OPTS</constant> holds
3054 options to pass to the C compiler when compiling the
3055 standard way. (<Xref LinkEnd="sec-ways"> dicusses
3056 multi-way compilation.)</para>
3061 <term><constant><module>_CC_OPTS</constant>:</term>
3063 <para>options to pass to the C compiler that are specific
3064 to module <literal><module></literal>. For example,
3065 <constant>SMap_CC_OPTS</constant> gives the
3066 specific options to pass to the C compiler when compiling
3067 <filename>SMap.c</filename>.</para>
3072 <term><constant>EXTRA_CC_OPTS</constant><indexterm><primary>EXTRA_CC_OPTS</primary></indexterm>:</term>
3074 <para>extra options to pass to all C compilations. This
3075 is intended for command line use, thus:</para>
3078 gmake libHS.a EXTRA_CC_OPTS="-v"
3085 <sect2 id="sec-targets">
3086 <title>The main <filename>mk/target.mk</filename> file</title>
3087 <indexterm><primary>target.mk</primary></indexterm>
3089 <para><filename>target.mk</filename> contains canned rules for
3090 all the standard targets described in <Xref
3091 LinkEnd="sec-standard-targets">. It is complicated by the fact
3092 that you don't want all of these rules to be active in every
3093 <filename>Makefile</filename>. Rather than have a plethora of
3094 tiny files which you can include selectively, there is a single
3095 file, <filename>target.mk</filename>, which selectively includes
3096 rules based on whether you have defined certain variables in
3097 your <filename>Makefile</filename>. This section explains what
3098 rules you get, what variables control them, and what the rules
3099 do. Hopefully, you will also get enough of an idea of what is
3100 supposed to happen that you can read and understand any weird
3101 special cases yourself.</para>
3105 <term><constant>HS_PROG</constant><indexterm><primary>HS_PROG</primary></indexterm>.</term>
3107 <para>If <constant>HS_PROG</constant> is defined,
3108 you get rules with the following targets:</para>
3112 <term><filename>HS_PROG</filename><indexterm><primary>HS_PROG</primary></indexterm></term>
3114 <para>itself. This rule links
3115 <constant>$(OBJS)</constant> with the Haskell
3116 runtime system to get an executable called
3117 <constant>$(HS_PROG)</constant>.</para>
3122 <term><literal>install</literal><indexterm><primary>install</primary></indexterm></term>
3125 <constant>$(HS_PROG)</constant> in
3126 <constant>$(bindir)</constant>.</para>
3135 <term><constant>C_PROG</constant><indexterm><primary>C_PROG</primary></indexterm></term>
3137 <para>is similar to <constant>HS_PROG</constant>,
3138 except that the link step links
3139 <constant>$(C_OBJS)</constant> with the C
3140 runtime system.</para>
3145 <term><constant>LIBRARY</constant><indexterm><primary>LIBRARY</primary></indexterm></term>
3147 <para>is similar to <constant>HS_PROG</constant>,
3148 except that it links
3149 <constant>$(LIB_OBJS)</constant> to make the
3150 library archive <constant>$(LIBRARY)</constant>,
3151 and <literal>install</literal> installs it in
3152 <constant>$(libdir)</constant>.</para>
3157 <term><constant>LIB_DATA</constant><indexterm><primary>LIB_DATA</primary></indexterm></term>
3159 <para>…</para>
3164 <term><constant>LIB_EXEC</constant><indexterm><primary>LIB_EXEC</primary></indexterm></term>
3166 <para>…</para>
3171 <term><constant>HS_SRCS</constant><indexterm><primary>HS_SRCS</primary></indexterm>, <constant>C_SRCS</constant><indexterm><primary>C_SRCS</primary></indexterm>.</term>
3173 <para>If <constant>HS_SRCS</constant> is defined
3174 and non-empty, a rule for the target
3175 <literal>depend</literal> is included, which generates
3176 dependency information for Haskell programs. Similarly
3177 for <constant>C_SRCS</constant>.</para>
3182 <para>All of these rules are “double-colon” rules,
3186 install :: $(HS_PROG)
3187 ...how to install it...
3190 <para>GNU <command>make</command> treats double-colon rules as
3191 separate entities. If there are several double-colon rules for
3192 the same target it takes each in turn and fires it if its
3193 dependencies say to do so. This means that you can, for
3194 example, define both <constant>HS_PROG</constant> and
3195 <constant>LIBRARY</constant>, which will generate two rules for
3196 <literal>install</literal>. When you type <command>gmake
3197 install</command> both rules will be fired, and both the program
3198 and the library will be installed, just as you wanted.</para>
3201 <sect2 id="sec-subdirs">
3202 <title>Recursion</title>
3203 <indexterm><primary>recursion, in makefiles</primary></indexterm>
3204 <indexterm><primary>Makefile, recursing into subdirectories</primary></indexterm>
3206 <para>In leaf <filename>Makefile</filename>s the variable
3207 <constant>SUBDIRS</constant><indexterm><primary>SUBDIRS</primary></indexterm>
3208 is undefined. In non-leaf <filename>Makefile</filename>s,
3209 <constant>SUBDIRS</constant> is set to the list of
3210 sub-directories that contain subordinate
3211 <filename>Makefile</filename>s. <emphasis>It is up to you to
3212 set <constant>SUBDIRS</constant> in the
3213 <filename>Makefile</filename>.</emphasis> There is no automation
3214 here—<constant>SUBDIRS</constant> is too important to
3217 <para>When <constant>SUBDIRS</constant> is defined,
3218 <filename>target.mk</filename> includes a rather neat rule for
3219 the standard targets (<Xref LinkEnd="sec-standard-targets"> that
3220 simply invokes <command>make</command> recursively in each of
3221 the sub-directories.</para>
3223 <para><emphasis>These recursive invocations are guaranteed to
3224 occur in the order in which the list of directories is specified
3225 in <constant>SUBDIRS</constant>. </emphasis>This guarantee can
3226 be important. For example, when you say <command>gmake
3227 boot</command> it can be important that the recursive invocation
3228 of <command>make boot</command> is done in one sub-directory
3229 (the include files, say) before another (the source files).
3230 Generally, put the most independent sub-directory first, and the
3231 most dependent last.</para>
3234 <sect2 id="sec-ways">
3235 <title>Way management</title>
3236 <indexterm><primary>way management</primary></indexterm>
3238 <para>We sometimes want to build essentially the same system in
3239 several different “ways”. For example, we want to build GHC's
3240 <literal>Prelude</literal> libraries with and without profiling,
3241 so that there is an appropriately-built library archive to link
3242 with when the user compiles his program. It would be possible
3243 to have a completely separate build tree for each such “way”,
3244 but it would be horribly bureaucratic, especially since often
3245 only parts of the build tree need to be constructed in multiple
3249 <filename>target.mk</filename><indexterm><primary>target.mk</primary></indexterm>
3250 contains some clever magic to allow you to build several
3251 versions of a system; and to control locally how many versions
3252 are built and how they differ. This section explains the
3255 <para>The files for a particular way are distinguished by
3256 munging the suffix. The <quote>normal way</quote> is always
3257 built, and its files have the standard suffices
3258 <filename>.o</filename>, <filename>.hi</filename>, and so on.
3259 In addition, you can build one or more extra ways, each
3260 distinguished by a <emphasis>way tag</emphasis>. The object
3261 files and interface files for one of these extra ways are
3262 distinguished by their suffix. For example, way
3263 <literal>mp</literal> has files
3264 <filename>.mp_o</filename> and
3265 <filename>.mp_hi</filename>. Library archives have their
3266 way tag the other side of the dot, for boring reasons; thus,
3267 <filename>libHS_mp.a</filename>.</para>
3269 <para>A <command>make</command> variable called
3270 <constant>way</constant> holds the current way tag.
3271 <emphasis><constant>way</constant> is only ever set on the
3272 command line of <command>gmake</command></emphasis> (usually in
3273 a recursive invocation of <command>gmake</command> by the
3274 system). It is never set inside a
3275 <filename>Makefile</filename>. So it is a global constant for
3276 any one invocation of <command>gmake</command>. Two other
3277 <command>make</command> variables,
3278 <constant>way_</constant> and
3279 <constant>_way</constant> are immediately derived from
3280 <constant>$(way)</constant> and never altered. If
3281 <constant>way</constant> is not set, then neither are
3282 <constant>way_</constant> and
3283 <constant>_way</constant>, and the invocation of
3284 <command>make</command> will build the <quote>normal
3285 way</quote>. If <constant>way</constant> is set, then the other
3286 two variables are set in sympathy. For example, if
3287 <constant>$(way)</constant> is “<literal>mp</literal>”,
3288 then <constant>way_</constant> is set to
3289 “<literal>mp_</literal>” and
3290 <constant>_way</constant> is set to
3291 “<literal>_mp</literal>”. These three variables are
3292 then used when constructing file names.</para>
3294 <para>So how does <command>make</command> ever get recursively
3295 invoked with <constant>way</constant> set? There are two ways
3296 in which this happens:</para>
3300 <para>For some (but not all) of the standard targets, when
3301 in a leaf sub-directory, <command>make</command> is
3302 recursively invoked for each way tag in
3303 <constant>$(WAYS)</constant>. You set
3304 <constant>WAYS</constant> in the
3305 <filename>Makefile</filename> to the list of way tags you
3306 want these targets built for. The mechanism here is very
3307 much like the recursive invocation of
3308 <command>make</command> in sub-directories (<Xref
3309 LinkEnd="sec-subdirs">). It is up to you to set
3310 <constant>WAYS</constant> in your
3311 <filename>Makefile</filename>; this is how you control what
3312 ways will get built.</para>
3316 <para>For a useful collection of targets (such as
3317 <filename>libHS_mp.a</filename>,
3318 <filename>Foo.mp_o</filename>) there is a rule which
3319 recursively invokes <command>make</command> to make the
3320 specified target, setting the <constant>way</constant>
3321 variable. So if you say <command>gmake
3322 Foo.mp_o</command> you should see a recursive
3323 invocation <command>gmake Foo.mp_o way=mp</command>,
3324 and <emphasis>in this recursive invocation the pattern rule
3325 for compiling a Haskell file into a <filename>.o</filename>
3326 file will match</emphasis>. The key pattern rules (in
3327 <filename>suffix.mk</filename>) look like this:
3331 $(HC) $(HC_OPTS) $< -o $@
3338 <para>You can invoke <command>make</command> with a
3339 particular <literal>way</literal> setting yourself, in order
3340 to build files related to a particular
3341 <literal>way</literal> in the current directory. eg.
3347 will build files for the profiling way only in the current
3354 <title>When the canned rule isn't right</title>
3356 <para>Sometimes the canned rule just doesn't do the right thing.
3357 For example, in the <literal>nofib</literal> suite we want the
3358 link step to print out timing information. The thing to do here
3359 is <emphasis>not</emphasis> to define
3360 <constant>HS_PROG</constant> or
3361 <constant>C_PROG</constant>, and instead define a special
3362 purpose rule in your own <filename>Makefile</filename>. By
3363 using different variable names you will avoid the canned rules
3364 being included, and conflicting with yours.</para>
3368 <sect1 id="building-docs">
3369 <title>Building the documentation</title>
3371 <sect2 id="pre-supposed-doc-tools">
3372 <title>Tools for building the Documentation</title>
3374 <para>The following additional tools are required if you want to
3375 format the documentation that comes with the
3376 <literal>fptools</literal> projects:</para>
3380 <term>DocBook</term>
3381 <indexterm><primary>pre-supposed: DocBook</primary></indexterm>
3382 <indexterm><primary>DocBook, pre-supposed</primary></indexterm>
3384 <para>Much of our documentation is written in SGML, using
3385 the DocBook DTD. Instructions on installing and
3386 configuring the DocBook tools are below.</para>
3392 <indexterm><primary>pre-supposed: TeX</primary></indexterm>
3393 <indexterm><primary>TeX, pre-supposed</primary></indexterm>
3395 <para>A decent TeX distribution is required if you want to
3396 produce printable documentation. We recomment teTeX,
3397 which includes just about everything you need.</para>
3402 <term>Haddock</term>
3403 <indexterm><primary>Haddock</primary>
3406 <para>Haddock is a Haskell documentation tool that we use
3407 for automatically generating documentation from the
3408 library source code. It is an <literal>fptools</literal>
3409 project in itself. To build documentation for the
3410 libraries (<literal>fptools/libraries</literal>) you
3411 should check out and build Haddock in
3412 <literal>fptools/haddock</literal>. Haddock requires GHC
3420 <title>Installing the DocBook tools</title>
3423 <title>Installing the DocBook tools on Linux</title>
3425 <para>If you're on a recent RedHat system (7.0+), you probably
3426 have working DocBook tools already installed. The configure
3427 script should detect your setup and you're away.</para>
3429 <para>If you don't have DocBook tools installed, and you are
3430 using a system that can handle RedHat RPM packages, you can
3431 probably use the <ULink
3432 URL="http://sourceware.cygnus.com/docbook-tools/">Cygnus
3433 DocBook tools</ULink>, which is the most shrink-wrapped SGML
3434 suite that we could find. You need all the RPMs except for
3435 psgml (i.e. <Filename>docbook</Filename>,
3436 <Filename>jade</Filename>, <Filename>jadetex</Filename>,
3437 <Filename>sgmlcommon</Filename> and
3438 <Filename>stylesheets</Filename>). Note that most of these
3439 RPMs are architecture neutral, so are likely to be found in a
3440 <Filename>noarch</Filename> directory. The SuSE RPMs also
3441 work; the RedHat ones <Emphasis>don't</Emphasis> in RedHat 6.2
3442 (7.0 and later should be OK), but they are easy to fix: just
3444 <Filename>/usr/lib/sgml/stylesheets/nwalsh-modular/lib/dblib.dsl</Filename>
3445 to <Filename>/usr/lib/sgml/lib/dblib.dsl</Filename>. </para>
3449 <title>Installing DocBook on FreeBSD</title>
3451 <para>On FreeBSD systems, the easiest way to get DocBook up
3452 and running is to install it from the ports tree or a
3453 pre-compiled package (packages are available from your local
3454 FreeBSD mirror site).</para>
3456 <para>To use the ports tree, do this:
3458 $ cd /usr/ports/textproc/docproj
3461 This installs the FreeBSD documentation project tools, which
3462 includes everything needed to format the GHC
3463 documentation.</para>
3467 <title>Installing from binaries on Windows</title>
3469 <Para>It's a good idea to use Norman Walsh's <ULink
3470 URL="http://nwalsh.com/docbook/dsssl/doc/install.html">installation
3471 notes</ULink> as a guide. You should get version 3.1 of
3472 DocBook, and note that his file <Filename>test.sgm</Filename>
3473 won't work, as it needs version 3.0. You should unpack Jade
3474 into <Filename>\Jade</Filename>, along with the entities,
3475 DocBook into <Filename>\docbook</Filename>, and the DocBook
3476 stylesheets into <Filename>\docbook\stylesheets</Filename> (so
3477 they actually end up in
3478 <Filename>\docbook\stylesheets\docbook</Filename>).</para>
3483 <title>Installing the DocBook tools from source</title>
3488 <para>Install <ULink
3489 URL="http://openjade.sourceforge.net/">OpenJade</ULink>
3490 (Windows binaries are available as well as sources). If you
3491 want DVI, PS, or PDF then install JadeTeX from the
3492 <Filename>dsssl</Filename> subdirectory. (If you get the
3496 ! LaTeX Error: Unknown option implicit=false' for package hyperref'.
3499 your version of <Command>hyperref</Command> is out of date;
3500 download it from CTAN
3501 (<Filename>macros/latex/contrib/supported/hyperref</Filename>),
3502 and make it, ensuring that you have first removed or renamed
3503 your old copy. If you start getting file not found errors
3504 when making the test for <Command>hyperref</Command>, you
3505 can abort at that point and proceed straight to
3506 <Command>make install</Command>, or enter them as
3507 <Filename>../</Filename><Emphasis>filename</Emphasis>.)</para>
3509 <para>Make links from <Filename>virtex</Filename> to
3510 <Filename>jadetex</Filename> and
3511 <Filename>pdfvirtex</Filename> to
3512 <Filename>pdfjadetex</Filename> (otherwise DVI, PostScript
3513 and PDF output will not work). Copy
3514 <Filename>dsssl/*.{dtd,dsl}</Filename> and
3515 <Filename>catalog</Filename> to
3516 <Filename>/usr/[local/]lib/sgml</Filename>.</para>
3520 <title>DocBook and the DocBook stylesheets</title>
3522 <para>Get a Zip of <ULink
3523 URL="http://www.oasis-open.org/docbook/sgml/3.1/index.html">DocBook</ULink>
3524 and install the contents in
3525 <Filename>/usr/[local/]/lib/sgml</Filename>.</para>
3527 <para>Get the <ULink
3528 URL="http://nwalsh.com/docbook/dsssl/">DocBook
3529 stylesheets</ULink> and install in
3530 <Filename>/usr/[local/]lib/sgml/stylesheets</Filename>
3531 (thereby creating a subdirectory docbook). For indexing,
3532 copy or link <Filename>collateindex.pl</Filename> from the
3533 DocBook stylesheets archive in <Filename>bin</Filename> into
3534 a directory on your <Constant>PATH</Constant>.</para>
3536 <para>Download the <ULink
3537 URL="http://www.oasis-open.org/cover/ISOEnts.zip">ISO
3538 entities</ULink> into
3539 <Filename>/usr/[local/]lib/sgml</Filename>.</para>
3545 <title>Configuring the DocBook tools</title>
3547 <Para>Once the DocBook tools are installed, the configure script
3548 will detect them and set up the build system accordingly. If you
3549 have a system that isn't supported, let us know, and we'll try
3554 <title>Remaining problems</title>
3556 <para>If you install from source, you'll get a pile of warnings
3559 <Screen>DTDDECL catalog entries are not supported</Screen>
3561 every time you build anything. These can safely be ignored, but
3562 if you find them tedious you can get rid of them by removing all
3563 the <Constant>DTDDECL</Constant> entries from
3564 <Filename>docbook.cat</Filename>.</para>
3568 <title>Building the documentation</title>
3570 <para>To build documentation in a certain format, you can
3571 say, for example,</para>
3577 <para>to build HTML documentation below the current directory.
3578 The available formats are: <literal>dvi</literal>,
3579 <literal>ps</literal>, <literal>pdf</literal>,
3580 <literal>html</literal>, and <literal>rtf</literal>. Note that
3581 not all documentation can be built in all of these formats: HTML
3582 documentation is generally supported everywhere, and DocBook
3583 documentation might support the other formats (depending on what
3584 other tools you have installed).</para>
3586 <para>All of these targets are recursive; that is, saying
3587 <literal>make html</literal> will make HTML docs for all the
3588 documents recursively below the current directory.</para>
3590 <para>Because there are many different formats that the DocBook
3591 documentation can be generated in, you have to select which ones
3592 you want by setting the <literal>SGMLDocWays</literal> variable
3593 to a list of them. For example, in
3594 <filename>build.mk</filename> you might have a line:</para>
3597 SGMLDocWays = html ps
3600 <para>This will cause the documentation to be built in the requested
3601 formats as part of the main build (the default is not to build
3602 any documentation at all).</para>
3606 <title>Installing the documentation</title>
3608 <para>To install the documentation, use:</para>
3614 <para>This will install the documentation into
3615 <literal>$(datadir)</literal> (which defaults to
3616 <literal>$(prefix)/share</literal>). The exception is HTML
3617 documentation, which goes into
3618 <literal>$(datadir)/html</literal>, to keep things tidy.</para>
3620 <para>Note that unless you set <literal>$(SGMLDocWays)</literal>
3621 to a list of formats, the <literal>install-docs</literal> target
3622 won't do anything for SGML documentation.</para>
3628 <sect1 id="sec-porting-ghc">
3629 <title>Porting GHC</title>
3631 <para>This section describes how to port GHC to a currenly
3632 unsupported platform. There are two distinct
3633 possibilities:</para>
3637 <para>The hardware architecture for your system is already
3638 supported by GHC, but you're running an OS that isn't
3639 supported (or perhaps has been supported in the past, but
3640 currently isn't). This is the easiest type of porting job,
3641 but it still requires some careful bootstrapping. Proceed to
3642 <xref linkend="sec-booting-from-hc">.</para>
3646 <para>Your system's hardware architecture isn't supported by
3647 GHC. This will be a more difficult port (though by comparison
3648 perhaps not as difficult as porting gcc). Proceed to <xref
3649 linkend="unregisterised-porting">.</para>
3653 <sect2 id="sec-booting-from-hc">
3654 <title>Booting/porting from C (<filename>.hc</filename>) files</title>
3656 <indexterm><primary>building GHC from .hc files</primary></indexterm>
3657 <indexterm><primary>booting GHC from .hc files</primary></indexterm>
3658 <indexterm><primary>porting GHC</primary></indexterm>
3660 <para>Bootstrapping GHC on a system without GHC already
3661 installed is achieved by taking the intermediate C files (known
3662 as HC files) from a GHC compilation on a supported system to the
3663 target machine, and compiling them using gcc to get a working
3666 <para><emphasis>NOTE: GHC versions 5.xx were hard to bootstrap
3667 from C. We recommend using GHC 6.0.1 or
3668 later.</emphasis></para>
3670 <para>HC files are platform-dependent, so you have to get a set
3671 that were generated on similar hardware. There may be some
3672 supplied on the GHC download page, otherwise you'll have to
3673 compile some up yourself, or start from
3674 <emphasis>unregisterised</emphasis> HC files - see <xref
3675 linkend="unregisterised-porting">.</para>
3677 <para>The following steps should result in a working GHC build
3678 with full libraries:</para>
3682 <para>Unpack the HC files on top of a fresh source tree
3683 (make sure the source tree version matches the version of
3684 the HC files <emphasis>exactly</emphasis>!). This will
3685 place matching <filename>.hc</filename> files next to the
3686 corresponding Haskell source (<filename>.hs</filename> or
3687 <filename>.lhs</filename>) in the compiler subdirectory
3688 <filename>ghc/compiler</filename> and in the libraries
3689 (subdirectories of <filename>hslibs</filename> and
3690 <literal>libraries</literal>).</para>
3694 <para>The actual build process is fully automated by the
3695 <filename>hc-build</filename> script located in the
3696 <filename>distrib</filename> directory. If you eventually
3697 want to install GHC into the directory
3698 <replaceable>dir</replaceable>, the following
3699 command will execute the whole build process (it won't
3700 install yet):</para>
3703 foo% distrib/hc-build --prefix=<replaceable>dir</replaceable>
3705 <indexterm><primary>--hc-build</primary></indexterm>
3707 <para>By default, the installation directory is
3708 <filename>/usr/local</filename>. If that is what you want,
3709 you may omit the argument to <filename>hc-build</filename>.
3710 Generally, any option given to <filename>hc-build</filename>
3711 is passed through to the configuration script
3712 <filename>configure</filename>. If
3713 <filename>hc-build</filename> successfully completes the
3714 build process, you can install the resulting system, as
3724 <sect2 id="unregisterised-porting">
3725 <title>Porting GHC to a new architecture</title>
3727 <para>The first step in porting to a new architecture is to get
3728 an <firstterm>unregisterised</firstterm> build working. An
3729 unregisterised build is one that compiles via vanilla C only.
3730 By contrast, a registerised build uses the following
3731 architecture-specific hacks for speed:</para>
3735 <para>Global register variables: certain abstract machine
3736 <quote>registers</quote> are mapped to real machine
3737 registers, depending on how many machine registers are
3739 <filename>ghc/includes/MachRegs.h</filename>).</para>
3743 <para>Assembly-mangling: when compiling via C, we feed the
3744 assembly generated by gcc though a Perl script known as the
3745 <firstterm>mangler</firstterm> (see
3746 <filename>ghc/driver/mangler/ghc-asm.lprl</filename>). The
3747 mangler rearranges the assembly to support tail-calls and
3748 various other optimisations.</para>
3752 <para>In an unregisterised build, neither of these hacks are
3753 used — the idea is that the C code generated by the
3754 compiler should compile using gcc only. The lack of these
3755 optimisations costs about a factor of two in performance, but
3756 since unregisterised compilation is usually just a step on the
3757 way to a full registerised port, we don't mind too much.</para>
3759 <para>Notes on GHC portability in general: we've tried to stick
3760 to writing portable code in most parts of the system, so it
3761 should compile on any POSIXish system with gcc, but in our
3762 experience most systems differ from the standards in one way or
3763 another. Deal with any problems as they arise - if you get
3764 stuck, ask the experts on
3765 <email>glasgow-haskell-users@haskell.org</email>.</para>
3767 <para>Lots of useful information about the innards of GHC is
3768 available in the <ulink
3769 url="http://www.cse.unsw.edu.au/~chak/haskell/ghc/comm/">GHC
3770 Commentary</ulink>, which might be helpful if you run into some
3771 code which needs tweaking for your system.</para>
3774 <title>Cross-compiling to produce an unregisterised GHC</title>
3776 <para>In this section, we explain how to bootstrap GHC on a
3777 new platform, using unregisterised intermediate C files. We
3778 haven't put a great deal of effort into automating this
3779 process, for two reasons: it is done very rarely, and the
3780 process usually requires human intervention to cope with minor
3781 porting issues anyway.</para>
3783 <para>The following step-by-step instructions should result in
3784 a fully working, albeit unregisterised, GHC. Firstly, you
3785 need a machine that already has a working GHC (we'll call this
3786 the <firstterm>host</firstterm> machine), in order to
3787 cross-compile the intermediate C files that we will use to
3788 bootstrap the compiler on the <firstterm>target</firstterm>
3793 <para>On the target machine:</para>
3797 <para>Unpack a source tree (preferably a released
3798 version). We will call the path to the root of this
3799 tree <replaceable>T</replaceable>.</para>
3804 $ cd <replaceable>T</replaceable>
3805 $ ./configure --enable-hc-boot --enable-hc-boot-unregisterised
3808 <para>You might need to update
3809 <filename>configure.in</filename> to recognise the new
3810 architecture, and re-generate
3811 <filename>configure</filename> with
3812 <literal>autoreconf</literal>.</para>
3817 $ cd <replaceable>T</replaceable>/ghc/includes
3825 <para>On the host machine:</para>
3829 <para>Unpack a source tree (same released version). Call
3830 this directory <replaceable>H</replaceable>.</para>
3835 $ cd <replaceable>H</replaceable>
3842 <filename><replaceable>H</replaceable>/mk/build.mk</filename>,
3843 with the following contents:</para>
3846 GhcUnregisterised = YES
3847 GhcLibHcOpts = -O -H32m -keep-hc-files
3850 GhcWithNativeCodeGen = NO
3851 GhcWithInterpreter = NO
3852 GhcStage1HcOpts = -O -H32m -fasm
3853 GhcStage2HcOpts = -O -fvia-C -keep-hc-files
3859 <filename><replaceable>H</replaceable>/mk/config.mk</filename>:</para>
3862 <para>change <literal>TARGETPLATFORM</literal>
3863 appropriately, and set the variables involving
3864 <literal>TARGET</literal> to the correct values for
3865 the target platform. This step is necessary because
3866 currently <literal>configure</literal> doesn't cope
3867 with specifying different values for the
3868 <literal>--host</literal> and
3869 <literal>--target</literal> flags.</para>
3872 <para>copy <literal>LeadingUnderscore</literal>
3873 setting from target.</para>
3880 <filename><replaceable>T</replaceable>/ghc/includes/config.h</filename>
3882 <filename><replaceable>H</replaceable>/ghc/includes</filename>.
3883 Note that we are building on the host machine, using the
3884 target machine's <literal>config.h</literal> file. This
3885 is so that the intermediate C files generated here will
3886 be suitable for compiling on the target system.</para>
3891 <para>Touch <literal>config.h</literal>, just to make
3892 sure it doesn't get replaced during the build:</para>
3894 $ touch <replaceable>H</replaceable>/ghc/includes/config.h</screen>
3898 <para>Now build the compiler:</para>
3900 $ cd <replaceable>H</replaceable>/glafp-utils && make boot && make
3901 $ cd <replaceable>H</replaceable>/ghc && make boot && make
3903 <para>Don't worry if the build falls over in the RTS, we
3904 don't need the RTS yet.</para>
3909 $ cd <replaceable>H</replaceable>/libraries
3910 $& make boot && make
3916 $ cd <replaceable>H</replaceable>/ghc
3917 $ make boot stage=2 && make stage=2
3923 $ cd <replaceable>H</replaceable>/ghc/utils
3925 $ make -k HC=<replaceable>H</replaceable>/ghc/compiler/stage1/ghc-inplace \
3926 EXTRA_HC_OPTS='-O -fvia-C -keep-hc-files'
3932 $ cd <replaceable>H</replaceable>
3933 $ make hc-file-bundle Project=Ghc
3939 <filename><replaceable>H</replaceable>/*-hc.tar.gz</filename>
3940 to <filename><replaceable>T</replaceable>/..</filename>.</para>
3946 <para>On the target machine:</para>
3948 <para>At this stage we simply need to bootstrap a compiler
3949 from the intermediate C files we generated above. The
3950 process of bootstrapping from C files is automated by the
3951 script in <literal>distrib/hc-build</literal>, and is
3952 described in <xref linkend="sec-booting-from-hc">.</para>
3955 $ ./distrib/hc-build --enable-hc-boot-unregisterised
3958 <para>However, since this is a bootstrap on a new machine,
3959 the automated process might not run to completion the
3960 first time. For that reason, you might want to treat the
3961 <literal>hc-build</literal> script as a list of
3962 instructions to follow, rather than as a fully automated
3963 script. This way you'll be able to restart the process
3964 part-way through if you need to fix anything on the
3967 <para>Don't bother with running
3968 <literal>make install</literal> in the newly
3969 bootstrapped tree; just use the compiler in that tree to
3970 build a fresh compiler from scratch, this time without
3971 booting from C files. Before doing this, you might want
3972 to check that the bootstrapped compiler is generating
3973 working binaries:</para>
3977 main = putStrLn "Hello World!\n"
3979 $ <replaceable>T</replaceable>/ghc/compiler/ghc-inplace hello.hs -o hello
3984 <para>Once you have the unregisterised compiler up and
3985 running, you can use it to start a registerised port. The
3986 following sections describe the various parts of the
3987 system that will need architecture-specific tweaks in
3988 order to get a registerised build going.</para>
3995 <title>Porting the RTS</title>
3997 <para>The following files need architecture-specific code for a
3998 registerised build:</para>
4002 <term><filename>ghc/includes/MachRegs.h</filename></term>
4003 <indexterm><primary><filename>MachRegs.h</filename></primary>
4006 <para>Defines the STG-register to machine-register
4007 mapping. You need to know your platform's C calling
4008 convention, and which registers are generally available
4009 for mapping to global register variables. There are
4010 plenty of useful comments in this file.</para>
4014 <term><filename>ghc/includes/TailCalls.h</filename></term>
4015 <indexterm><primary><filename>TailCalls.h</filename></primary>
4018 <para>Macros that cooperate with the mangler (see <xref
4019 linkend="sec-mangler">) to make proper tail-calls
4024 <term><filename>ghc/rts/Adjustor.c</filename></term>
4025 <indexterm><primary><filename>Adjustor.c</filename></primary>
4029 <literal>foreign import "wrapper"</literal>
4031 <literal>foreign export dynamic</literal>).
4032 Not essential for getting GHC bootstrapped, so this file
4033 can be deferred until later if necessary.</para>
4037 <term><filename>ghc/rts/StgCRun.c</filename></term>
4038 <indexterm><primary><filename>StgCRun.c</filename></primary>
4041 <para>The little assembly layer between the C world and
4042 the Haskell world. See the comments and code for the
4043 other architectures in this file for pointers.</para>
4047 <term><filename>ghc/rts/MBlock.h</filename></term>
4048 <term><filename>ghc/rts/MBlock.c</filename></term>
4049 <indexterm><primary><filename>MBlock.h</filename></primary>
4051 <indexterm><primary><filename>MBlock.c</filename></primary>
4054 <para>These files are really OS-specific rather than
4055 architecture-specific. In <filename>MBlock.h</filename>
4056 is specified the absolute location at which the RTS
4057 should try to allocate memory on your platform (try to
4058 find an area which doesn't conflict with code or dynamic
4059 libraries). In <filename>Mblock.c</filename> you might
4060 need to tweak the call to <literal>mmap()</literal> for
4067 <sect3 id="sec-mangler">
4068 <title>The mangler</title>
4070 <para>The mangler is an evil Perl-script that rearranges the
4071 assembly code output from gcc to do two main things:</para>
4075 <para>Remove function prologues and epilogues, and all
4076 movement of the C stack pointer. This is to support
4077 tail-calls: every code block in Haskell code ends in an
4078 explicit jump, so we don't want the C-stack overflowing
4079 while we're jumping around between code blocks.</para>
4082 <para>Move the <firstterm>info table</firstterm> for a
4083 closure next to the entry code for that closure. In
4084 unregisterised code, info tables contain a pointer to the
4085 entry code, but in registerised compilation we arrange
4086 that the info table is shoved right up against the entry
4087 code, and addressed backwards from the entry code pointer
4088 (this saves a word in the info table and an extra
4089 indirection when jumping to the closure entry
4094 <para>The mangler is abstracted to a certain extent over some
4095 architecture-specific things such as the particular assembler
4096 directives used to herald symbols. Take a look at the
4097 definitions for other architectures and use these as a
4098 starting point.</para>
4102 <title>The native code generator</title>
4104 <para>The native code generator isn't essential to getting a
4105 registerised build going, but it's a desirable thing to have
4106 because it can cut compilation times in half. The native code
4107 generator is described in some detail in the <ulink
4108 url="http://www.cse.unsw.edu.au/~chak/haskell/ghc/comm/">GHC
4109 commentary</ulink>.</para>
4115 <para>To support GHCi, you need to port the dynamic linker
4116 (<filename>fptools/ghc/rts/Linker.c</filename>). The linker
4117 currently supports the ELF and PEi386 object file formats - if
4118 your platform uses one of these then things will be
4119 significantly easier. The majority of Unix platforms use the
4120 ELF format these days. Even so, there are some
4121 machine-specific parts of the ELF linker: for example, the
4122 code for resolving particular relocation types is
4123 machine-specific, so some porting of this code to your
4124 architecture will probaly be necessary.</para>
4126 <para>If your system uses a different object file format, then
4127 you have to write a linker — good luck!</para>
4133 <sect1 id="sec-build-pitfalls">
4134 <title>Known pitfalls in building Glasgow Haskell
4136 <indexterm><primary>problems, building</primary></indexterm>
4137 <indexterm><primary>pitfalls, in building</primary></indexterm>
4138 <indexterm><primary>building pitfalls</primary></indexterm></title>
4141 WARNINGS about pitfalls and known “problems”:
4150 One difficulty that comes up from time to time is running out of space
4151 in <literal>TMPDIR</literal>. (It is impossible for the configuration stuff to
4152 compensate for the vagaries of different sysadmin approaches to temp
4154 <indexterm><primary>tmp, running out of space in</primary></indexterm>
4156 The quickest way around it is <command>setenv TMPDIR /usr/tmp</command><indexterm><primary>TMPDIR</primary></indexterm> or
4157 even <command>setenv TMPDIR .</command> (or the equivalent incantation with your shell
4160 The best way around it is to say
4163 export TMPDIR=<dir>
4166 in your <filename>build.mk</filename> file.
4167 Then GHC and the other <literal>fptools</literal> programs will use the appropriate directory
4176 In compiling some support-code bits, e.g., in <filename>ghc/rts/gmp</filename> and even
4177 in <filename>ghc/lib</filename>, you may get a few C-compiler warnings. We think these
4185 When compiling via C, you'll sometimes get “warning: assignment from
4186 incompatible pointer type” out of GCC. Harmless.
4193 Similarly, <command>ar</command>chiving warning messages like the following are not
4197 ar: filename GlaIOMonad__1_2s.o truncated to GlaIOMonad_
4198 ar: filename GlaIOMonad__2_2s.o truncated to GlaIOMonad_
4208 In compiling the compiler proper (in <filename>compiler/</filename>), you <emphasis>may</emphasis>
4209 get an “Out of heap space” error message. These can vary with the
4210 vagaries of different systems, it seems. The solution is simple:
4217 If you're compiling with GHC 4.00 or later, then the
4218 <emphasis>maximum</emphasis> heap size must have been reached. This
4219 is somewhat unlikely, since the maximum is set to 64M by default.
4220 Anyway, you can raise it with the
4221 <option>-optCrts-M<size></option> flag (add this flag to
4222 <constant><module>_HC_OPTS</constant>
4223 <command>make</command> variable in the appropriate
4224 <filename>Makefile</filename>).
4231 For GHC < 4.00, add a suitable <option>-H</option> flag to the <filename>Makefile</filename>, as
4240 and try again: <command>gmake</command>. (see <Xref LinkEnd="sec-suffix"> for information about
4241 <constant><module>_HC_OPTS</constant>.)
4243 Alternatively, just cut to the chase:
4247 % make EXTRA_HC_OPTS=-optCrts-M128M
4256 If you try to compile some Haskell, and you get errors from GCC about
4257 lots of things from <filename>/usr/include/math.h</filename>, then your GCC was
4258 mis-installed. <command>fixincludes</command> wasn't run when it should've been.
4260 As <command>fixincludes</command> is now automagically run as part of GCC installation,
4261 this bug also suggests that you have an old GCC.
4269 You <emphasis>may</emphasis> need to re-<command>ranlib</command><indexterm><primary>ranlib</primary></indexterm> your libraries (on Sun4s).
4273 % cd $(libdir)/ghc-x.xx/sparc-sun-sunos4
4274 % foreach i ( `find . -name '*.a' -print` ) # or other-shell equiv...
4276 ? # or, on some machines: ar s $i
4281 We'd be interested to know if this is still necessary.
4289 GHC's sources go through <command>cpp</command> before being compiled, and <command>cpp</command> varies
4290 a bit from one Unix to another. One particular gotcha is macro calls
4295 SLIT("Hello, world")
4299 Some <command>cpp</command>s treat the comma inside the string as separating two macro
4300 arguments, so you get
4304 :731: macro `SLIT' used with too many (2) args
4308 Alas, <command>cpp</command> doesn't tell you the offending file!
4310 Workaround: don't put weird things in string args to <command>cpp</command> macros.
4321 <Sect1 id="winbuild"><Title>Notes for building under Windows</Title>
4324 This section summarises how to get the utilities you need on your
4325 Win95/98/NT/2000 machine to use CVS and build GHC. Similar notes for
4326 installing and running GHC may be found in the user guide. In general,
4327 Win95/Win98 behave the same, and WinNT/Win2k behave the same.
4328 You should read the GHC installation guide sections on Windows (in the user
4329 guide) before continuing to read these notes.
4333 <sect2 id="cygwin-and-mingw"><Title>Cygwin and MinGW</Title>
4335 <para> The Windows situation for building GHC is rather confusing. This section
4336 tries to clarify, and to establish terminology.</para>
4338 <sect3 id="ghc-mingw"><title>GHC-mingw</title>
4340 <para> <ulink url="http://www.mingw.org">MinGW (Minimalist GNU for Windows)</ulink>
4341 is a collection of header
4342 files and import libraries that allow one to use <command>gcc</command> and produce
4343 native Win32 programs that do not rely on any third-party DLLs. The
4344 current set of tools include GNU Compiler Collection (<command>gcc</command>), GNU Binary
4345 Utilities (Binutils), GNU debugger (Gdb), GNU make, and a assorted
4348 <para>The GHC that we distribute includes, inside the distribution itself, the MinGW <command>gcc</command>,
4349 <command>as</command>, <command>ld</command>, and a bunch of input/output libraries.
4350 GHC compiles Haskell to C (or to
4351 assembly code), and then invokes these MinGW tools to generate an executable binary.
4352 The resulting binaries can run on any Win32 system.
4354 <para> We will call a GHC that targets MinGW in this way <emphasis>GHC-mingw</emphasis>.</para>
4356 <para> The down-side of GHC-mingw is that the MinGW libraries do not support anything like the full
4357 Posix interface. So programs compiled with GHC-mingw cannot import the (Haskell) Posix
4358 library; they have to do
4359 their input output using standard Haskell I/O libraries, or native Win32 bindings.
4363 <sect3 id="ghc-cygwin"><title>GHC-cygwin</title>
4365 <para>There <emphasis>is</emphasis> a way to get the full Posix interface, which is to use Cygwin.
4366 <ulink url="http://www.cygwin.com">Cygwin</ulink> is a complete Unix simulation that runs on Win32.
4367 Cygwin comes with a shell, and all the usual Unix commands: <command>mv</command>, <command>rm</command>,
4368 <command>ls</command>, plus of course <command>gcc</command>, <command>ld</command> and so on.
4369 A C program compiled with the Cygwin <command>gcc</command> certainly can use all of Posix.
4371 <para>So why doesn't GHC use the Cygwin <command>gcc</command> and libraries? Because
4372 Cygwin comes with a DLL <emphasis>that must be linked with every runnable Cygwin-compiled program</emphasis>.
4373 A program compiled by the Cygwin tools cannot run at all unless Cygwin is installed.
4374 If GHC targeted Cygwin, users would have to install Cygwin just to run the Haskell programs
4375 that GHC compiled; and the Cygwin DLL would have to be in the DLL load path.
4376 Worse, Cygwin is a moving target. The name of the main DLL, <literal>cygwin1.dll</literal>
4377 does not change, but the implementation certainly does. Even the interfaces to functions
4378 it exports seem to change occasionally. So programs compiled by GHC might only run with
4379 particular versions of Cygwin. All of this seems very undesirable.
4382 Nevertheless, it is certainly possible to build a version of GHC that targets Cygwin;
4383 we will call that <emphasis>GHC-cygwin</emphasis>. The up-side of GHC-cygwin is
4384 that Haskell programs compiled by GHC-cygwin can import the (Haskell) Posix library.
4388 <sect3><title>HOST_OS vs TARGET_OS</title>
4391 In the source code you'll find various ifdefs looking like:
4393 #ifdef mingw32_HOST_OS
4399 #ifdef mingw32_TARGET_OS
4403 These macros are set by the configure script (via the file config.h).
4404 Which is which? The criterion is this. In the ifdefs in GHC's source code:
4407 The "host" system is the one on which GHC itself will be run.
4410 The "target" system is the one for which the program compiled by GHC will be run.
4413 For a stage-2 compiler, in which GHCi is available, the "host" and "target" systems must be the same.
4414 So then it doesn't really matter whether you use the HOST_OS or TARGET_OS cpp macros.
4419 <sect3><title>Summary</title>
4421 <para>Notice that "GHC-mingw" means "GHC that <emphasis>targets</emphasis> MinGW". It says nothing about
4422 how that GHC was <emphasis>built</emphasis>. It is entirely possible to have a GHC-mingw that was built
4423 by compiling GHC's Haskell sources with a GHC-cygwin, or vice versa.</para>
4425 <para>We distribute only a GHC-mingw built by a GHC-mingw; supporting
4426 GHC-cygwin too is beyond our resources. The GHC we distribute
4427 therefore does not require Cygwin to run, nor do the programs it
4428 compiles require Cygwin.</para>
4430 <para>The instructions that follow describe how to build GHC-mingw. It is
4431 possible to build GHC-cygwin, but it's not a supported route, and the build system might
4434 <para>In your build tree, you build a compiler called <Command>ghc-inplace</Command>. It
4435 uses the <Command>gcc</Command> that you specify using the
4436 <option>--with-gcc</option> flag when you run
4437 <Command>configure</Command> (see below).
4438 The makefiles are careful to use <Command>ghc-inplace</Command> (not <Command>gcc</Command>)
4439 to compile any C files, so that it will in turn invoke the right <Command>gcc</Command> rather that
4440 whatever one happens to be in your path. However, the makefiles do use whatever <Command>ld</Command>
4441 and <Command>ar</Command> happen to be in your path. This is a bit naughty, but (a) they are only
4442 used to glom together .o files into a bigger .o file, or a .a file,
4443 so they don't ever get libraries (which would be bogus; they might be the wrong libraries), and (b)
4444 Cygwin and Mingw use the same .o file format. So its ok.
4449 <Sect2><Title>Installing and configuring Cygwin</Title>
4451 <para>You don't need Cygwin to <emphasis>use</emphasis> GHC,
4452 but you do need it to <emphasis>build</emphasis> GHC.</para>
4454 <para> Install Cygwin from <ulink url="http://www.cygwin.com/">http://www.cygwin.com/</ulink>.
4455 The installation process is straightforward; we install it in <Filename>c:/cygwin</Filename>.
4456 During the installation dialogue, make sure that you select all of the following:
4459 <command>cvs</command>,
4462 <command>openssh</command>,
4465 <command>autoreconf</command>,
4468 <command>automake</command>,
4471 <command>binutils</command> (includes ld and (I think) ar),
4474 <command>gcc</command>,
4477 <command>flex</command>,
4480 <command>make</command>.
4483 If you miss out any of these, strange things will happen to you. To see thse packages,
4484 click on the "View" button in the "Select Packages"
4485 stage of Cygwin's installation dialogue, until the view says "Full". The default view, which is
4486 "Category" isn't very helpful, and the "View" button is rather unobtrousive.
4488 <para> Now set the following user environment variables:
4491 <listitem><para> Add <filename>c:/cygwin/bin</filename> and <filename>c:/cygwin/usr/bin</filename> to your
4492 <constant>PATH</constant></para></listitem>
4496 Set <constant>MAKE_MODE</constant> to <Literal>UNIX</Literal>. If you
4497 don't do this you get very weird messages when you type
4498 <Command>make</Command>, such as:
4500 /c: /c: No such file or directory
4505 <listitem><para> Set <constant>SHELL</constant> to
4506 <Filename>c:/cygwin/bin/bash</Filename>. When you invoke a shell in Emacs, this
4507 <constant>SHELL</constant> is what you get.
4510 <listitem><para> Set <constant>HOME</constant> to point to your
4511 home directory. This is where, for example,
4512 <command>bash</command> will look for your <filename>.bashrc</filename>
4513 file. Ditto <command>emacs</command> looking for <filename>.emacsrc</filename>
4519 There are a few other things to do:
4523 By default, cygwin provides the command shell <filename>ash</filename>
4524 as <filename>sh.exe</filename>. We have often seen build-system problems that
4525 turn out to be due to bugs in <filename>ash</filename>
4527 and length of command lines). On the other hand <filename>bash</filename> seems
4529 So, in <filename>cygwin/bin</filename>
4530 remove the supplied <filename>sh.exe</filename> (or rename it as <filename>ash.exe</filename>),
4531 and copy <filename>bash.exe</filename> to <filename>sh.exe</filename>.
4532 You'll need to do this in Windows Explorer or the Windows <command>cmd</command> shell, because
4533 you can't rename a running program!
4539 Some script files used in the make system start with "<Command>#!/bin/perl</Command>",
4540 (and similarly for <Command>sh</Command>). Notice the hardwired path!
4541 So you need to ensure that your <Filename>/bin</Filename> directory has the following
4544 <listitem> <para><Command>sh</Command></para></listitem>
4545 <listitem> <para><Command>perl</Command></para></listitem>
4546 <listitem> <para><Command>cat</Command></para></listitem>
4548 All these come in Cygwin's <Filename>bin</Filename> directory, which you probably have
4549 installed as <Filename>c:/cygwin/bin</Filename>. By default Cygwin mounts "<Filename>/</Filename>" as
4550 <Filename>c:/cygwin</Filename>, so if you just take the defaults it'll all work ok.
4551 (You can discover where your Cygwin
4552 root directory <Filename>/</Filename> is by typing <Command>mount</Command>.)
4553 Provided <Filename>/bin</Filename> points to the Cygwin <Filename>bin</Filename>
4554 directory, there's no need to copy anything. If not, copy these binaries from the <filename>cygwin/bin</filename>
4555 directory (after fixing the <filename>sh.exe</filename> stuff mentioned in the previous bullet).
4561 <para>Finally, here are some things to be aware of when using Cygwin:
4563 <listitem> <para>Cygwin doesn't deal well with filenames that include
4564 spaces. "<filename>Program Files</filename>" and "<filename>Local files</filename>" are
4568 <listitem> <para> Cygwin implements a symbolic link as a text file with some
4569 magical text in it. So other programs that don't use Cygwin's
4570 I/O libraries won't recognise such files as symlinks.
4571 In particular, programs compiled by GHC are meant to be runnable
4572 without having Cygwin, so they don't use the Cygwin library, so
4573 they don't recognise symlinks.
4577 Win32 has a <command>find</command> command which is not the same as Cygwin's find.
4578 You will probably discover that the Win32 <command>find</command> appears in your <constant>PATH</constant>
4579 before the Cygwin one, because it's in the <emphasis>system</emphasis> <constant>PATH</constant>
4580 environment variable, whereas you have probably modified the <emphasis>user</emphasis> <constant>PATH</constant>
4581 variable. You can always invoke <command>find</command> with an absolute path, or rename it.
4588 <Sect2 id="configure-ssh"><Title>Configuring SSH</Title>
4590 <para><command>ssh</command> comes with Cygwin, provided you remember to ask for it when
4591 you install Cygwin. (If not, the installer lets you update easily.) Look for <command>openssh</command>
4592 (not ssh) in the Cygwin list of applications!</para>
4594 <para>There are several strange things about <command>ssh</command> on Windows that you need to know.
4598 The programs <command>ssh-keygen1</command>, <command>ssh1</command>, and <command>cvs</command>,
4599 seem to lock up <command>bash</command> entirely if they try to get user input (e.g. if
4600 they ask for a password). To solve this, start up <filename>cmd.exe</filename>
4601 and run it as follows:
4603 c:\tmp> set CYGWIN32=tty
4604 c:\tmp> c:/user/local/bin/ssh-keygen1
4609 <command>ssh</command> needs to access your directory <filename>.ssh</filename>, in your home directory.
4610 To determine your home directory <command>ssh</command> first looks in
4611 <filename>c:/cygwin/etc/passwd</filename> (or wherever you have Cygwin installed). If there's an entry
4612 there with your userid, it'll use that entry to determine your home directory, <emphasis>ignoring
4613 the setting of the environment variable $HOME</emphasis>. If the home directory is
4614 bogus, <command>ssh</command> fails horribly. The best way to see what is going on is to say
4616 ssh -v cvs.haskell.org
4618 which makes <command>ssh</command> print out information about its activity.
4620 <para> You can fix this problem, either by correcting the home-directory field in
4621 <filename>c:/cygwin/etc/passwd</filename>, or by simply deleting the entire entry for your userid. If
4622 you do that, <command>ssh</command> uses the $HOME environment variable instead.
4628 <para>To protect your
4629 <literal>.ssh</literal> from access by anyone else,
4630 right-click your <literal>.ssh</literal> directory, and
4631 select <literal>Properties</literal>. If you are not on
4632 the access control list, add yourself, and give yourself
4633 full permissions (the second panel). Remove everyone else
4634 from the access control list. Don't leave them there but
4635 deny them access, because 'they' may be a list that
4636 includes you!</para>
4640 <para>In fact <command>ssh</command> 3.6.1 now seems to <emphasis>require</emphasis>
4641 you to have Unix permissions 600 (read/write for owner only)
4642 on the <literal>.ssh/identity</literal> file, else it
4643 bombs out. For your local C drive, it seems that <literal>chmod 600 identity</literal> works,
4644 but on Windows NT/XP, it doesn't work on a network drive (exact dteails obscure).
4645 The solution seems to be to set the $CYGWIN environment
4646 variable to "<literal>ntsec neta</literal>". The $CYGWIN environment variable is discussed
4647 in <ulink url="http://cygwin.com/cygwin-ug-net/using-cygwinenv.html">the Cygwin User's Guide</ulink>,
4648 and there are more details in <ulink url="http://cygwin.com/faq/faq_4.html#SEC44">the Cygwin FAQ</ulink>.
4655 <Sect2><Title>Other things you need to install</Title>
4657 <para>You have to install the following other things to build GHC:
4661 Install an executable GHC, from <ulink url="http://www.haskell.org/ghc">http://www.haskell.org/ghc</ulink>.
4662 This is what you will use to compile GHC. Add it in your
4663 <constant>PATH</constant>: the installer tells you the path element
4664 you need to add upon completion.
4670 Install an executable Happy, from <ulink url="http://www.haskell.org/happy">http://www.haskell.org/happy</ulink>.
4671 Happy is a parser generator used to compile the Haskell grammar. Add it in your
4672 <constant>PATH</constant>.
4677 <para>Install Alex. This can be done by building from the
4678 source distribution in the usual way. Sources are
4679 available from <ulink
4680 url="http://www.haskell.org/alex">http://www.haskell.org/alex</ulink>.</para>
4684 <para>GHC uses the <emphasis>mingw</emphasis> C compiler to
4685 generate code, so you have to install that (see <xref linkend="cygwin-and-mingw">).
4686 Just pick up a mingw bundle at
4687 <ulink url="http://www.mingw.org/">http://www.mingw.org/</ulink>.
4688 We install it in <filename>c:/mingw</filename>.
4690 <para>Do <emphasis>not</emphasis> add any of the <emphasis>mingw</emphasis> binaries to your path.
4691 They are only going to get used by explicit access (via the --with-gcc flag you
4692 give to <Command>configure</Command> later). If you do add them to your path
4693 you are likely to get into a mess because their names overlap with Cygwin binaries.
4699 <para>We use <command>emacs</command> a lot, so we install that too.
4700 When you are in <filename>fptools/ghc/compiler</filename>, you can use
4701 "<literal>make tags</literal>" to make a TAGS file for emacs. That uses the utility
4702 <filename>fptools/ghc/utils/hasktags/hasktags</filename>, so you need to make that first.
4703 The most convenient way to do this is by going <literal>make boot</literal> in <filename>fptools/ghc</filename>.
4704 The <literal>make tags</literal> command also uses <command>etags</command>, which comes with <command>emacs</command>,
4705 so you will need to add <filename>emacs/bin</filename> to your <literal>PATH</literal>.
4711 <para> Finally, check out a copy of GHC sources from
4712 the CVS repository, following the instructions above (<xref linkend="cvs-access">).
4719 <Sect2><Title>Building GHC</Title>
4722 Now go read the documentation above on building from source (<xref linkend="sec-building-from-source">);
4723 the bullets below only tell
4724 you about Windows-specific wrinkles.</para>
4728 Run <Command>autoreconf</Command> both in <filename>fptools</filename>
4729 and in <filename>fptools/ghc</filename>. If you omit the latter step you'll
4730 get an error when you run <filename>./configure</filename>:
4733 creating mk/config.h
4734 mk/config.h is unchanged
4736 running /bin/sh ./configure --cache-file=.././config.cache --srcdir=.
4737 ./configure: ./configure: No such file or directory
4738 configure: error: ./configure failed for ghc
4743 <listitem> <para><command>autoreconf</command> seems to create the file <filename>configure</filename>
4744 read-only. So if you need to run autoreconf again (which I sometimes do for safety's sake),
4747 /usr/bin/autoreconf: cannot create configure: permission denied
4749 Solution: delete <filename>configure</filename> first.
4754 You either need to add <filename>ghc</filename> to your
4755 <constant>PATH</constant> before you invoke
4756 <Command>configure</Command>, or use the <Command>configure</Command>
4757 option <option>--with-ghc=c:/ghc/ghc-some-version/bin/ghc</option>.
4762 If you are paranoid, delete <filename>config.cache</filename> if it exists.
4763 This file occasionally remembers out-of-date configuration information, which
4764 can be really confusing.
4770 After <command>autoreconf</command> run <command>./configure</command> in
4771 <filename>fptools/</filename> thus:
4774 ./configure --host=i386-unknown-mingw32 --with-gcc=c:/mingw/bin/gcc
4776 This is the point at which you specify that you are building GHC-mingw
4777 (see <xref linkend="ghc-mingw">). </para>
4779 <para> Both these options are important! It's possible to get into
4780 trouble using the wrong C compiler!</para>
4782 Furthermore, it's <emphasis>very important</emphasis> that you specify a
4783 full MinGW path for <command>gcc</command>, not a Cygwin path, because GHC (which
4784 uses this path to invoke <command>gcc</command>) is a MinGW program and won't
4785 understand a Cygwin path. For example, if you
4786 say <literal>--with-gcc=/mingw/bin/gcc</literal>, it'll be interpreted as
4787 <filename>/cygdrive/c/mingw/bin/gcc</filename>, and GHC will fail the first
4788 time it tries to invoke it. Worse, the failure comes with
4789 no error message whatsoever. GHC simply fails silently when first invoked,
4790 typically leaving you with this:
4792 make[4]: Leaving directory `/cygdrive/e/fptools-stage1/ghc/rts/gmp'
4793 ../../ghc/compiler/ghc-inplace -optc-mno-cygwin -optc-O
4794 -optc-Wall -optc-W -optc-Wstrict-prototypes -optc-Wmissing-prototypes
4795 -optc-Wmissing-declarations -optc-Winline -optc-Waggregate-return
4796 -optc-Wbad-function-cast -optc-Wcast-align -optc-I../includes
4797 -optc-I. -optc-Iparallel -optc-DCOMPILING_RTS
4798 -optc-fomit-frame-pointer -O2 -static
4799 -package-name rts -O -dcore-lint -c Adjustor.c -o Adjustor.o
4800 make[2]: *** [Adjustor.o] Error 1
4801 make[1]: *** [all] Error 1
4802 make[1]: Leaving directory `/cygdrive/e/fptools-stage1/ghc'
4803 make: *** [all] Error 1
4809 If you want to build GHC-cygwin (<xref linkend="ghc-cygwin">)
4810 you'll have to do something more like:
4812 ./configure --with-gcc=...the Cygwin gcc...
4817 <listitem><para> You almost certainly want to set
4821 in your <filename>build.mk</filename> configuration file (see <xref linkend="sec-build-config">).
4822 This tells the build system not to split each library into a myriad of little object files, one
4823 for each function. Doing so reduces binary sizes for statically-linked binaries, but on Windows
4824 it dramatically increases the time taken to build the libraries in the first place.
4828 <listitem><para> Do not attempt to build the documentation.
4829 It needs all kinds of wierd Jade stuff that we haven't worked out for
4830 Win32.</para></listitem>
projects / ghc-hetmet.git / blob