installing-packages.rst 62 KB
Newer Older
1 2 3
Configuration
=============

4 5
.. highlight:: cabal

6 7 8 9 10 11 12 13
Overview
--------

The global configuration file for ``cabal-install`` is
``~/.cabal/config``. If you do not have this file, ``cabal`` will create
it for you on the first call to ``cabal update``. Alternatively, you can
explicitly ask ``cabal`` to create it for you using

14 15 16
.. code-block:: console

    $ cabal user-config update
17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Most of the options in this configuration file are also available as
command line arguments, and the corresponding documentation can be used
to lookup their meaning. The created configuration file only specifies
values for a handful of options. Most options are left at their default
value, which it documents; for instance,

::

    -- executable-stripping: True

means that the configuration file currently does not specify a value for
the ``executable-stripping`` option (the line is commented out), and
that the default is ``True``; if you wanted to disable stripping of
executables by default, you would change this line to

::

    executable-stripping: False

You can also use ``cabal user-config update`` to migrate configuration
files created by older versions of ``cabal``.

Repository specification
------------------------

An important part of the configuration if the specification of the
repository. When ``cabal`` creates a default config file, it configures
the repository to be the central Hackage server:

::

    repository hackage.haskell.org
      url: http://hackage.haskell.org/

The name of the repository is given on the first line, and can be
anything; packages downloaded from this repository will be cached under
``~/.cabal/packages/hackage.haskell.org`` (or whatever name you specify;
you can change the prefix by changing the value of
``remote-repo-cache``). If you want, you can configure multiple
repositories, and ``cabal`` will combine them and be able to download
packages from any of them.

Using secure repositories
61
^^^^^^^^^^^^^^^^^^^^^^^^^
62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98

For repositories that support the TUF security infrastructure (this
includes Hackage), you can enable secure access to the repository by
specifying:

::

    repository hackage.haskell.org
      url: http://hackage.haskell.org/
      secure: True
      root-keys: <root-key-IDs>
      key-threshold: <key-threshold>

The ``<root-key-IDs>`` and ``<key-threshold>`` values are used for
bootstrapping. As part of the TUF infrastructure the repository will
contain a file ``root.json`` (for instance,
http://hackage.haskell.org/root.json) which the client needs to do
verification. However, how can ``cabal`` verify the ``root.json`` file
*itself*? This is known as bootstrapping: if you specify a list of root
key IDs and a corresponding threshold, ``cabal`` will verify that the
downloaded ``root.json`` file has been signed with at least
``<key-threshold>`` keys from your set of ``<root-key-IDs>``.

You can, but are not recommended to, omit these two fields. In that case
``cabal`` will download the ``root.json`` field and use it without
verification. Although this bootstrapping step is then unsafe, all
subsequent access is secure (provided that the downloaded ``root.json``
was not tempered with). Of course, adding ``root-keys`` and
``key-threshold`` to your repository specification only shifts the
problem, because now you somehow need to make sure that the key IDs you
received were the right ones. How that is done is however outside the
scope of ``cabal`` proper.

More information about the security infrastructure can be found at
https://github.com/well-typed/hackage-security.

Legacy repositories
99
^^^^^^^^^^^^^^^^^^^
100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131

Currently ``cabal`` supports two kinds of legacy repositories. The
first is specified using

::

    remote-repo: hackage.haskell.org:http://hackage.haskell.org/packages/archive

This is just syntactic sugar for

::

    repository hackage.haskell.org
      url: hackage.haskell.org:http://hackage.haskell.org/packages/archive

although, in (and only in) the specific case of Hackage, the URL
``http://hackage.haskell.org/packages/archive`` will be silently
translated to ``http://hackage.haskell.org/``.

The second kind of legacy repositories are so-called local
repositories:

::

    local-repo: my-local-repo:/path/to/local/repo

This can be used to access repositories on the local file system.
However, the layout of these local repositories is different from the
layout of remote repositories, and usage of these local repositories is
deprecated.

Secure local repositories
132
^^^^^^^^^^^^^^^^^^^^^^^^^
133 134 135 136

If you want to use repositories on your local file system, it is
recommended instead to use a *secure* local repository:

137
::
138 139 140 141 142 143 144 145

    repository my-local-repo
      url: file:/path/to/local/repo
      secure: True
      root-keys: <root-key-IDs>
      key-threshold: <key-threshold>

The layout of these secure local repos matches the layout of remote
146
repositories exactly; the :hackage-pkg:`hackage-repo-tool`
147 148
can be used to create and manage such repositories.

149 150
.. _installing-packages:

151 152 153
Building and installing packages
================================

154 155
.. highlight:: console

156 157 158
After you've unpacked a Cabal package, you can build it by moving into
the root directory of the package and running the ``cabal`` tool there:

159 160 161
::

    $ cabal [command] [option...]
162 163 164 165 166 167

The *command* argument selects a particular step in the build/install
process.

You can also get a summary of the command syntax with

168 169 170
::

    $ cabal help
171 172 173 174

Alternatively, you can also use the ``Setup.hs`` or ``Setup.lhs``
script:

175 176 177
::

    $ runhaskell Setup.hs [command] [option...]
178 179 180

For the summary of the command syntax, run:

181 182 183
::

    $ cabal help
184 185 186

or

187 188 189
::

    $ runhaskell Setup.hs --help
190 191 192 193

Building and installing a system package
----------------------------------------

194
::
195

196 197 198
    $ runhaskell Setup.hs configure --ghc
    $ runhaskell Setup.hs build
    $ runhaskell Setup.hs install
199 200 201 202 203 204 205 206 207

The first line readies the system to build the tool using GHC; for
example, it checks that GHC exists on the system. The second line
performs the actual building, while the last both copies the build
results to some permanent place and registers the package with GHC.

Building and installing a user package
--------------------------------------

208
::
209

210 211 212
    $ runhaskell Setup.hs configure --user
    $ runhaskell Setup.hs build
    $ runhaskell Setup.hs install
213 214

The package is installed under the user's home directory and is
215
registered in the user's package database (:option:`setup configure --user`).
216 217 218 219 220

Installing packages from Hackage
--------------------------------

The ``cabal`` tool also can download, configure, build and install a
221
Hackage_ package and all of its
222 223 224 225
dependencies in a single step. To do this, run:

::

226
   $ cabal install [PACKAGE...]
227 228

To browse the list of available packages, visit the
229
Hackage_ web site.
230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246

Developing with sandboxes
-------------------------

By default, any dependencies of the package are installed into the
global or user package databases (e.g. using
``cabal install --only-dependencies``). If you're building several
different packages that have incompatible dependencies, this can cause
the build to fail. One way to avoid this problem is to build each
package in an isolated environment ("sandbox"), with a sandbox-local
package database. Because sandboxes are per-project, inconsistent
dependencies can be simply disallowed.

For more on sandboxes, see also `this
article <http://coldwa.st/e/blog/2013-08-20-Cabal-sandbox.html>`__.

Sandboxes: basic usage
247
^^^^^^^^^^^^^^^^^^^^^^
248 249 250 251 252

To initialise a fresh sandbox in the current directory, run
``cabal sandbox init``. All subsequent commands (such as ``build`` and
``install``) from this point will use the sandbox.

253
::
254 255 256 257 258 259 260 261 262

    $ cd /path/to/my/haskell/library
    $ cabal sandbox init                   # Initialise the sandbox
    $ cabal install --only-dependencies    # Install dependencies into the sandbox
    $ cabal build                          # Build your package inside the sandbox

It can be useful to make a source package available for installation in
the sandbox - for example, if your package depends on a patched or an
unreleased version of a library. This can be done with the
263 264
``cabal sandbox add-source`` command - think of it as "local Hackage_".
If an add-source dependency is later modified, it is reinstalled automatically.
265

266
::
267 268 269 270 271 272 273 274 275 276 277 278 279 280 281

    $ cabal sandbox add-source /my/patched/library # Add a new add-source dependency
    $ cabal install --dependencies-only            # Install it into the sandbox
    $ cabal build                                  # Build the local package
    $ $EDITOR /my/patched/library/Source.hs        # Modify the add-source dependency
    $ cabal build                                  # Modified dependency is automatically reinstalled

Normally, the sandbox settings (such as optimisation level) are
inherited from the main Cabal config file (``$HOME/cabal/config``).
Sometimes, though, you need to change some settings specifically for a
single sandbox. You can do this by creating a ``cabal.config`` file in
the same directory with your ``cabal.sandbox.config`` (which was created
by ``sandbox init``). This file has the same syntax as the main Cabal
config file.

282
::
283 284 285 286 287 288 289 290 291

    $ cat cabal.config
    documentation: True
    constraints: foo == 1.0, bar >= 2.0, baz
    $ cabal build                                  # Uses settings from the cabal.config file

When you have decided that you no longer want to build your package
inside a sandbox, just delete it:

292
::
293 294 295 296 297

    $ cabal sandbox delete                       # Built-in command
    $ rm -rf .cabal-sandbox cabal.sandbox.config # Alternative manual method

Sandboxes: advanced usage
298
^^^^^^^^^^^^^^^^^^^^^^^^^
299 300 301 302 303 304 305 306 307 308 309

The default behaviour of the ``add-source`` command is to track
modifications done to the added dependency and reinstall the sandbox
copy of the package when needed. Sometimes this is not desirable: in
these cases you can use ``add-source --snapshot``, which disables the
change tracking. In addition to ``add-source``, there are also
``list-sources`` and ``delete-source`` commands.

Sometimes one wants to share a single sandbox between multiple packages.
This can be easily done with the ``--sandbox`` option:

310
::
311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327

    $ mkdir -p /path/to/shared-sandbox
    $ cd /path/to/shared-sandbox
    $ cabal sandbox init --sandbox .
    $ cd /path/to/package-a
    $ cabal sandbox init --sandbox /path/to/shared-sandbox
    $ cd /path/to/package-b
    $ cabal sandbox init --sandbox /path/to/shared-sandbox

Note that ``cabal sandbox init --sandbox .`` puts all sandbox files into
the current directory. By default, ``cabal sandbox init`` initialises a
new sandbox in a newly-created subdirectory of the current working
directory (``./.cabal-sandbox``).

Using multiple different compiler versions simultaneously is also
supported, via the ``-w`` option:

328
::
329 330 331 332 333 334 335 336 337 338 339 340 341 342 343

    $ cabal sandbox init
    $ cabal install --only-dependencies -w /path/to/ghc-1 # Install dependencies for both compilers
    $ cabal install --only-dependencies -w /path/to/ghc-2
    $ cabal configure -w /path/to/ghc-1                   # Build with the first compiler
    $ cabal build
    $ cabal configure -w /path/to/ghc-2                   # Build with the second compiler
    $ cabal build

It can be occasionally useful to run the compiler-specific package
manager tool (e.g. ``ghc-pkg``) tool on the sandbox package DB directly
(for example, you may need to unregister some packages). The
``cabal sandbox hc-pkg`` command is a convenient wrapper that runs the
compiler-specific package manager tool with the arguments:

344
::
345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383

    $ cabal -v sandbox hc-pkg list
    Using a sandbox located at /path/to/.cabal-sandbox
    'ghc-pkg' '--global' '--no-user-package-conf'
        '--package-conf=/path/to/.cabal-sandbox/i386-linux-ghc-7.4.2-packages.conf.d'
        'list'
    [...]

The ``--require-sandbox`` option makes all sandbox-aware commands
(``install``/``build``/etc.) exit with error if there is no sandbox
present. This makes it harder to accidentally modify the user package
database. The option can be also turned on via the per-user
configuration file (``~/.cabal/config``) or the per-project one
(``$PROJECT_DIR/cabal.config``). The error can be squelched with
``--no-require-sandbox``.

The option ``--sandbox-config-file`` allows to specify the location of
the ``cabal.sandbox.config`` file (by default, ``cabal`` searches for it
in the current directory). This provides the same functionality as
shared sandboxes, but sometimes can be more convenient. Example:

::

    $ mkdir my/sandbox
    $ cd my/sandbox
    $ cabal sandbox init
    $ cd /path/to/my/project
    $ cabal --sandbox-config-file=/path/to/my/sandbox/cabal.sandbox.config install
    # Uses the sandbox located at /path/to/my/sandbox/.cabal-sandbox
    $ cd ~
    $ cabal --sandbox-config-file=/path/to/my/sandbox/cabal.sandbox.config install
    # Still uses the same sandbox

The sandbox config file can be also specified via the
``CABAL_SANDBOX_CONFIG`` environment variable.

Finally, the flag ``--ignore-sandbox`` lets you temporarily ignore an
existing sandbox:

384
::
385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400

    $ mkdir my/sandbox
    $ cd my/sandbox
    $ cabal sandbox init
    $ cabal --ignore-sandbox install text
    # Installs 'text' in the user package database ('~/.cabal').

Creating a binary package
-------------------------

When creating binary packages (e.g. for Red Hat or Debian) one needs to
create a tarball that can be sent to another system for unpacking in the
root directory:

::

401 402 403 404
    $ runhaskell Setup.hs configure --prefix=/usr
    $ runhaskell Setup.hs build
    $ runhaskell Setup.hs copy --destdir=/tmp/mypkg
    $ tar -czf mypkg.tar.gz /tmp/mypkg/
405 406 407 408 409

If the package contains a library, you need two additional steps:

::

410 411
    $ runhaskell Setup.hs register --gen-script
    $ runhaskell Setup.hs unregister --gen-script
412 413 414 415 416 417 418 419 420 421

This creates shell scripts ``register.sh`` and ``unregister.sh``, which
must also be sent to the target system. After unpacking there, the
package must be registered by running the ``register.sh`` script. The
``unregister.sh`` script would be used in the uninstall procedure of the
package. Similar steps may be used for creating binary packages for
Windows.

The following options are understood by all commands:

422 423 424 425
.. program:: setup

.. option:: --help, -h or -?

426
    List the available options for the command.
427 428 429

.. option:: --verbose=n or -v n

430 431 432
    Set the verbosity level (0-3). The normal level is 1; a missing *n*
    defaults to 2.

433 434 435 436 437 438 439 440 441
    There is also an extended version of this command which can be
    used to fine-tune the verbosity of output.  It takes the
    form ``[silent|normal|verbose|debug]``\ *flags*, where *flags*
    is a list of ``+`` flags which toggle various aspects of
    output.  At the moment, only ``+callsite`` and ``+callstack``
    are supported, which respectively toggle call site and call
    stack printing (these are only supported if Cabal
    is built with a sufficiently recent GHC.)

442 443 444 445
The various commands and the additional options they support are
described below. In the simple build infrastructure, any other options
will be reported as errors.

446 447
.. _setup-configure:

448 449 450
setup configure
---------------

451 452
.. program:: setup configure

453 454 455 456 457 458 459 460 461 462 463 464 465 466
Prepare to build the package. Typically, this step checks that the
target platform is capable of building the package, and discovers
platform-specific features that are needed during the build.

The user may also adjust the behaviour of later stages using the options
listed in the following subsections. In the simple build infrastructure,
the values supplied via these options are recorded in a private file
read by later stages.

If a user-supplied ``configure`` script is run (see the section on
`system-dependent
parameters <developing-packages.html#system-dependent-parameters>`__ or
on `complex
packages <developing-packages.html#more-complex-packages>`__), it is
467
passed the :option:`--with-hc-pkg`, :option:`--prefix`, :option:`--bindir`,
Christiaan Baaij's avatar
Christiaan Baaij committed
468
:option:`--libdir`, :option:`--dynlibdir`, :option:`--datadir`, :option:`--libexecdir` and
469 470 471
:option:`--sysconfdir` options. In addition the value of the
:option:`--with-compiler` option is passed in a :option:`--with-hc-pkg` option
and all options specified with :option:`--configure-option` are passed on.
472

473 474 475 476 477 478 479
.. note::
   `GNU autoconf places restrictions on paths, including the directory
   that the package is built from.
   <https://www.gnu.org/software/autoconf/manual/autoconf.html#File-System-Conventions>`_
   The errors produced when this happens can be obscure; Cabal attempts to
   detect and warn in this situation, but it is not perfect.

480 481 482 483 484 485 486
In Cabal 2.0, support for a single positional argument was added to
``setup configure`` This makes Cabal configure a the specific component
to be configured. Specified names can be qualified with ``lib:`` or
``exe:`` in case just a name is ambiguous (as would be the case for a
package named ``p`` which has a library and an executable named ``p``.)
This has the following effects:

487
-  Subsequent invocations of ``cabal build``, ``register``, etc. operate only
488 489 490 491
   on the configured component.

-  Cabal requires all "internal" dependencies (e.g., an executable
   depending on a library defined in the same package) must be found in
492
   the set of databases via :option:`--package-db` (and related flags): these
493
   dependencies are assumed to be up-to-date. A dependency can be
494
   explicitly specified using :option:`--dependency` simply by giving the name
495 496 497 498 499
   of the internal library; e.g., the dependency for an internal library
   named ``foo`` is given as
   ``--dependency=pkg-internal=pkg-1.0-internal-abcd``.

-  Only the dependencies needed for the requested component are
500 501
   required. Similarly, when :option:`--exact-configuration` is specified,
   it's only necessary to specify :option:`--dependency` for the component.
502 503 504
   (As mentioned previously, you *must* specify internal dependencies as
   well.)

505 506
-  Internal ``build-tool-depends`` and ``build-tools`` dependencies are expected
   to be in the ``PATH`` upon subsequent invocations of ``setup``.
507 508 509 510 511

Full details can be found in the `Componentized Cabal
proposal <https://github.com/ezyang/ghc-proposals/blob/master/proposals/0000-componentized-cabal.rst>`__.

Programs used for building
512
^^^^^^^^^^^^^^^^^^^^^^^^^^
513 514 515 516

The following options govern the programs used to process the source
files of a package:

517 518
.. option:: --ghc or -g, --jhc, --lhc, --uhc

519 520 521 522
    Specify which Haskell implementation to use to build the package. At
    most one of these flags may be given. If none is given, the
    implementation under which the setup script was compiled or
    interpreted is used.
523 524 525

.. option:: --with-compiler=path or -w *path*

526 527 528 529
    Specify the path to a particular compiler. If given, this must match
    the implementation selected above. The default is to search for the
    usual name of the selected implementation.

530
    This flag also sets the default value of the :option:`--with-hc-pkg`
531 532
    option to the package tool for this compiler. Check the output of
    ``setup configure -v`` to ensure that it finds the right package
533 534 535
    tool (or use :option:`--with-hc-pkg` explicitly).

.. option:: --with-hc-pkg=path
536 537 538

    Specify the path to the package tool, e.g. ``ghc-pkg``. The package
    tool must be compatible with the compiler specified by
539
    :option:`--with-compiler`. If this option is omitted, the default value is
540
    determined from the compiler selected.
541 542 543

.. option:: --with-prog=path

544 545 546 547 548 549 550
    Specify the path to the program *prog*. Any program known to Cabal
    can be used in place of *prog*. It can either be a fully path or the
    name of a program that can be found on the program search path. For
    example: ``--with-ghc=ghc-6.6.1`` or
    ``--with-cpphs=/usr/local/bin/cpphs``. The full list of accepted
    programs is not enumerated in this user guide. Rather, run
    ``cabal install --help`` to view the list.
551 552 553

.. option:: --prog-options=options

554 555 556 557 558 559 560
    Specify additional options to the program *prog*. Any program known
    to Cabal can be used in place of *prog*. For example:
    ``--alex-options="--template=mytemplatedir/"``. The *options* is
    split into program options based on spaces. Any options containing
    embedded spaced need to be quoted, for example
    ``--foo-options='--bar="C:\Program File\Bar"'``. As an alternative
    that takes only one option at a time but avoids the need to quote,
561 562 563 564
    use :option:`--prog-option` instead.

.. option:: --prog-option=option

565 566
    Specify a single additional option to the program *prog*. For
    passing an option that contain embedded spaces, such as a file name
567 568 569
    with embedded spaces, using this rather than :option:`--prog-options`
    means you do not need an additional level of quoting. Of course if you
    are using a command shell you may still need to quote, for example
570 571
    ``--foo-options="--bar=C:\Program File\Bar"``.

572 573
All of the options passed with either :option:`--prog-options`
or :option:`--prog-option` are passed in the order they were
574 575 576
specified on the configure command line.

Installation paths
577
^^^^^^^^^^^^^^^^^^
578 579 580 581

The following options govern the location of installed files from a
package:

582 583
.. option:: --prefix=dir

584 585 586 587 588 589 590 591 592
    The root of the installation. For example for a global install you
    might use ``/usr/local`` on a Unix system, or ``C:\Program Files``
    on a Windows system. The other installation paths are usually
    subdirectories of *prefix*, but they don't have to be.

    In the simple build system, *dir* may contain the following path
    variables: ``$pkgid``, ``$pkg``, ``$version``, ``$compiler``,
    ``$os``, ``$arch``, ``$abi``, ``$abitag``

593 594
.. option:: --bindir=dir

595 596 597 598
    Executables that the user might invoke are installed here.

    In the simple build system, *dir* may contain the following path
    variables: ``$prefix``, ``$pkgid``, ``$pkg``, ``$version``,
599
    ``$compiler``, ``$os``, ``$arch``, ``$abi``, ``$abitag``
600

601 602
.. option:: --libdir=dir

603 604 605 606 607 608 609
    Object-code libraries are installed here.

    In the simple build system, *dir* may contain the following path
    variables: ``$prefix``, ``$bindir``, ``$pkgid``, ``$pkg``,
    ``$version``, ``$compiler``, ``$os``, ``$arch``, ``$abi``,
    ``$abitag``

Christiaan Baaij's avatar
Christiaan Baaij committed
610 611 612 613 614 615 616 617 618 619 620 621
.. option:: --dynlibdir=dir

    Dynamic libraries are installed here.

    By default, this is set to `$libdir/$abi`, which is usually not equal to
    `$libdir/$libsubdir`.

    In the simple build system, *dir* may contain the following path
    variables: ``$prefix``, ``$bindir``, ``$libdir``, ``$pkgid``, ``$pkg``,
    ``$version``, ``$compiler``, ``$os``, ``$arch``, ``$abi``,
    ``$abitag``

622 623
.. option:: --libexecdir=dir

624 625 626 627 628 629 630 631
    Executables that are not expected to be invoked directly by the user
    are installed here.

    In the simple build system, *dir* may contain the following path
    variables: ``$prefix``, ``$bindir``, ``$libdir``, ``$libsubdir``,
    ``$pkgid``, ``$pkg``, ``$version``, ``$compiler``, ``$os``,
    ``$arch``, ``$abi``, ``$abitag``

632 633
.. option:: --datadir=dir

634 635 636 637 638 639 640
    Architecture-independent data files are installed here.

    In the simple build system, *dir* may contain the following path
    variables: ``$prefix``, ``$bindir``, ``$libdir``, ``$libsubdir``,
    ``$pkgid``, ``$pkg``, ``$version``, ``$compiler``, ``$os``,
    ``$arch``, ``$abi``, ``$abitag``

641 642
.. option:: --sysconfdir=dir

643 644 645 646 647 648 649 650 651 652
    Installation directory for the configuration files.

    In the simple build system, *dir* may contain the following path
    variables: ``$prefix``, ``$bindir``, ``$libdir``, ``$libsubdir``,
    ``$pkgid``, ``$pkg``, ``$version``, ``$compiler``, ``$os``,
    ``$arch``, ``$abi``, ``$abitag``

In addition the simple build system supports the following installation
path options:

653 654
.. option:: --libsubdir=dir

655 656 657 658 659
    A subdirectory of *libdir* in which libraries are actually installed. For
    example, in the simple build system on Unix, the default *libdir* is
    ``/usr/local/lib``, and *libsubdir* contains the compiler ABI and package
    identifier,
    e.g. ``x86_64-linux-ghc-8.0.2/mypkg-0.1.0-IxQNmCA7qrSEQNkoHSF7A``, so
660
    libraries would be installed in
661
    ``/usr/local/lib/x86_64-linux-ghc-8.0.2/mypkg-0.1.0-IxQNmCA7qrSEQNkoHSF7A/``.
662 663

    *dir* may contain the following path variables: ``$pkgid``,
664 665 666 667 668
    ``$pkg``, ``$version``, ``$compiler``, ``$os``, ``$arch``, ``$abi``,
    ``$abitag``

.. option:: --libexecsubdir=dir

669 670 671 672 673
    A subdirectory of *libexecdir* in which private executables are
    installed. For example, in the simple build system on Unix, the default
    *libexecdir* is ``/usr/local/libexec``, and *libsubdir* is
    ``x86_64-linux-ghc-8.0.2/mypkg-0.1.0``, so private executables would be
    installed in ``/usr/local/libexec/x86_64-linux-ghc-8.0.2/mypkg-0.1.0/``
674 675

    *dir* may contain the following path variables: ``$pkgid``,
676 677 678
    ``$pkg``, ``$version``, ``$compiler``, ``$os``, ``$arch``, ``$abi``,
    ``$abitag``

679 680
.. option:: --datasubdir=dir

681 682 683 684 685 686 687
    A subdirectory of *datadir* in which data files are actually
    installed.

    *dir* may contain the following path variables: ``$pkgid``,
    ``$pkg``, ``$version``, ``$compiler``, ``$os``, ``$arch``, ``$abi``,
    ``$abitag``

688 689
.. option:: --docdir=dir

690 691 692 693 694 695 696
    Documentation files are installed relative to this directory.

    *dir* may contain the following path variables: ``$prefix``,
    ``$bindir``, ``$libdir``, ``$libsubdir``, ``$datadir``,
    ``$datasubdir``, ``$pkgid``, ``$pkg``, ``$version``, ``$compiler``,
    ``$os``, ``$arch``, ``$abi``, ``$abitag``

697 698
.. option:: --htmldir=dir

699 700 701 702 703 704 705
    HTML documentation files are installed relative to this directory.

    *dir* may contain the following path variables: ``$prefix``,
    ``$bindir``, ``$libdir``, ``$libsubdir``, ``$datadir``,
    ``$datasubdir``, ``$docdir``, ``$pkgid``, ``$pkg``, ``$version``,
    ``$compiler``, ``$os``, ``$arch``, ``$abi``, ``$abitag``

706 707
.. option:: --program-prefix=prefix

708 709 710 711 712 713
    Prepend *prefix* to installed program names.

    *prefix* may contain the following path variables: ``$pkgid``,
    ``$pkg``, ``$version``, ``$compiler``, ``$os``, ``$arch``, ``$abi``,
    ``$abitag``

714 715
.. option:: --program-suffix=suffix

716 717 718 719 720 721 722 723 724 725
    Append *suffix* to installed program names. The most obvious use for
    this is to append the program's version number to make it possible
    to install several versions of a program at once:
    ``--program-suffix='$version'``.

    *suffix* may contain the following path variables: ``$pkgid``,
    ``$pkg``, ``$version``, ``$compiler``, ``$os``, ``$arch``, ``$abi``,
    ``$abitag``

Path variables in the simple build system
726
"""""""""""""""""""""""""""""""""""""""""
727 728 729 730 731 732 733 734 735

For the simple build system, there are a number of variables that can be
used when specifying installation paths. The defaults are also specified
in terms of these variables. A number of the variables are actually for
other paths, like ``$prefix``. This allows paths to be specified
relative to each other rather than as absolute paths, which is important
for building relocatable packages (see `prefix
independence <#prefix-independence>`__).

736
$prefix
737 738 739
    The path variable that stands for the root of the installation. For
    an installation to be relocatable, all other installation paths must
    be relative to the ``$prefix`` variable.
740 741
$bindir
    The path variable that expands to the path given by the :option:`--bindir`
742
    configure option (or the default).
743 744 745 746
$libdir
    As above but for :option:`--libdir`
$libsubdir
    As above but for :option:`--libsubdir`
Christiaan Baaij's avatar
Christiaan Baaij committed
747 748
$dynlibdir
    As above but for :option:`--dynlibdir`
749 750 751 752 753 754 755
$datadir
    As above but for :option:`--datadir`
$datasubdir
    As above but for :option:`--datasubdir`
$docdir
    As above but for :option:`--docdir`
$pkgid
756
    The name and version of the package, e.g. ``mypkg-0.2``
757
$pkg
758
    The name of the package, e.g. ``mypkg``
759
$version
760
    The version of the package, e.g. ``0.2``
761
$compiler
762
    The compiler being used to build the package, e.g. ``ghc-6.6.1``
763
$os
764 765 766
    The operating system of the computer being used to build the
    package, e.g. ``linux``, ``windows``, ``osx``, ``freebsd`` or
    ``solaris``
767
$arch
768 769
    The architecture of the computer being used to build the package,
    e.g. ``i386``, ``x86_64``, ``ppc`` or ``sparc``
770
$abitag
771 772 773
    An optional tag that a compiler can use for telling incompatible
    ABI's on the same architecture apart. GHCJS encodes the underlying
    GHC version in the ABI tag.
774
$abi
775 776 777 778 779 780
    A shortcut for getting a path that completely identifies the
    platform in terms of binary compatibility. Expands to the same value
    as ``$arch-$os-compiler-$abitag`` if the compiler uses an abi tag,
    ``$arch-$os-$compiler`` if it doesn't.

Paths in the simple build system
781
""""""""""""""""""""""""""""""""
782 783 784

For the simple build system, the following defaults apply:

785 786 787 788
.. list-table:: Default installation paths

    * - Option
      - Unix Default
789
      - Windows Default
790 791
    * - :option:`--prefix` (global)
      - ``/usr/local``
792
      - ``%PROGRAMFILES%\Haskell``
793 794
    * - :option:`--prefix` (per-user)
      - ``$HOME/.cabal``
795
      - ``%APPDATA%\cabal``
796 797
    * - :option:`--bindir`
      - ``$prefix/bin``
798
      - ``$prefix\bin``
799 800
    * - :option:`--libdir`
      - ``$prefix/lib``
801
      - ``$prefix``
802 803
    * - :option:`--libsubdir` (others)
      - ``$pkgid/$compiler``
804
      - ``$pkgid\$compiler``
Christiaan Baaij's avatar
Christiaan Baaij committed
805 806 807
    * - :option:`--dynlibdir`
      - ``$libdir/$abi``
      - ``$libdir\$abi``
808 809
    * - :option:`--libexecdir`
      - ``$prefix/libexec``
810
      - ``$prefix\$pkgid``
811 812
    * - :option:`--datadir` (executable)
      - ``$prefix/share``
813
      - ``$prefix``
814 815
    * - :option:`--datadir` (library)
      - ``$prefix/share``
816
      - ``%PROGRAMFILES%\Haskell``
817 818 819 820 821
    * - :option:`--datasubdir`
      - ``$pkgid``
      - ``$pkgid``
    * - :option:`--docdir`
      - ``$datadir/doc/$pkgid``
822
      - ``$prefix\doc\$pkgid``
823 824
    * - :option:`--sysconfdir`
      - ``$prefix/etc``
825
      - ``$prefix\etc``
826 827
    * - :option:`--htmldir`
      - ``$docdir/html``
828
      - ``$docdir\html``
829 830 831 832 833 834
    * - :option:`--program-prefix`
      - (empty)
      - (empty)
    * - :option:`--program-suffix`
      - (empty)
      - (empty)
835 836

Prefix-independence
837
"""""""""""""""""""
838 839 840 841 842 843 844 845 846 847 848

On Windows it is possible to obtain the pathname of the running program.
This means that we can construct an installable executable package that
is independent of its absolute install location. The executable can find
its auxiliary files by finding its own path and knowing the location of
the other files relative to ``$bindir``. Prefix-independence is
particularly useful: it means the user can choose the install location
(i.e. the value of ``$prefix``) at install-time, rather than having to
bake the path into the binary when it is built.

In order to achieve this, we require that for an executable on Windows,
Christiaan Baaij's avatar
Christiaan Baaij committed
849
all of ``$bindir``, ``$libdir``, ``$dynlibdir``, ``$datadir`` and ``$libexecdir`` begin
850 851 852 853 854 855 856 857 858 859 860 861 862 863 864
with ``$prefix``. If this is not the case then the compiled executable
will have baked-in all absolute paths.

The application need do nothing special to achieve prefix-independence.
If it finds any files using ``getDataFileName`` and the `other functions
provided for the
purpose <developing-packages.html#accessing-data-files-from-package-code>`__,
the files will be accessed relative to the location of the current
executable.

A library cannot (currently) be prefix-independent, because it will be
linked into an executable whose file system location bears no relation
to the library package.

Controlling Flag Assignments
865
^^^^^^^^^^^^^^^^^^^^^^^^^^^^
866 867 868 869 870

Flag assignments (see the `resolution of conditions and
flags <developing-packages.html#resolution-of-conditions-and-flags>`__)
can be controlled with the following command line options.

871 872
.. option:: -f flagname or -f -flagname

873 874 875 876
    Force the specified flag to ``true`` or ``false`` (if preceded with
    a ``-``). Later specifications for the same flags will override
    earlier, i.e., specifying ``-fdebug -f-debug`` is equivalent to
    ``-f-debug``
877 878 879

.. option:: --flags=flagspecs

880 881 882 883 884 885 886 887
    Same as ``-f``, but allows specifying multiple flag assignments at
    once. The parameter is a space-separated list of flag names (to
    force a flag to ``true``), optionally preceded by a ``-`` (to force
    a flag to ``false``). For example,
    ``--flags="debug -feature1 feature2"`` is equivalent to
    ``-fdebug -f-feature1 -ffeature2``.

Building Test Suites
888
^^^^^^^^^^^^^^^^^^^^
889

890 891
.. option:: --enable-tests

892 893 894 895 896
    Build the test suites defined in the package description file during
    the ``build`` stage. Check for dependencies required by the test
    suites. If the package is configured with this option, it will be
    possible to run the test suites with the ``test`` command after the
    package is built.
897 898 899

.. option:: --disable-tests

900 901 902 903
    (default) Do not build any test suites during the ``build`` stage.
    Do not check for dependencies required only by the test suites. It
    will not be possible to invoke the ``test`` command without
    reconfiguring the package.
904 905 906

.. option:: --enable-coverage

907 908 909
    Build libraries and executables (including test suites) with Haskell
    Program Coverage enabled. Running the test suites will automatically
    generate coverage reports with HPC.
910 911 912

.. option:: --disable-coverage

913 914 915
    (default) Do not enable Haskell Program Coverage.

Miscellaneous options
916
^^^^^^^^^^^^^^^^^^^^^
917

918 919
.. option:: --user

920 921 922 923 924 925 926
    Does a per-user installation. This changes the `default installation
    prefix <#paths-in-the-simple-build-system>`__. It also allow
    dependencies to be satisfied by the user's package database, in
    addition to the global database. This also implies a default of
    ``--user`` for any subsequent ``install`` command, as packages
    registered in the global database should not depend on packages
    registered in a user's database.
927 928 929

.. option:: --global

930 931 932 933
    (default) Does a global installation. In this case package
    dependencies must be satisfied by the global package database. All
    packages in the user's package database will be ignored. Typically
    the final installation step will require administrative privileges.
934 935 936

.. option:: --package-db=db

937 938 939 940 941 942 943
    Allows package dependencies to be satisfied from this additional
    package database *db* in addition to the global package database.
    All packages in the user's package database will be ignored. The
    interpretation of *db* is implementation-specific. Typically it will
    be a file or directory. Not all implementations support arbitrary
    package databases.

944 945
    This pushes an extra db onto the db stack. The :option:`--global` and
    :option:`--user` mode switches add the respective [Global] and [Global,
946 947 948 949 950 951 952
    User] dbs to the initial stack. There is a compiler-implementation
    constraint that the global db must appear first in the stack, and if
    the user one appears at all, it must appear immediately after the
    global db.

    To reset the stack, use ``--package-db=clear``.

953 954
.. option:: --ipid=ipid

955 956 957 958 959 960 961
    Specifies the *installed package identifier* of the package to be
    built; this identifier is passed on to GHC and serves as the basis
    for linker symbols and the ``id`` field in a ``ghc-pkg``
    registration. When a package has multiple components, the actual
    component identifiers are derived off of this identifier (e.g., an
    internal library ``foo`` from package ``p-0.1-abcd`` will get the
    identifier ``p-0.1-abcd-foo``.
962 963 964

.. option:: --cid=cid

965 966
    Specifies the *component identifier* of the component being built;
    this is only valid if you are configuring a single component.
967 968 969

.. option:: --default-user-config=file

970 971 972 973 974 975
    Allows a "default" ``cabal.config`` freeze file to be passed in
    manually. This file will only be used if one does not exist in the
    project directory already. Typically, this can be set from the
    global cabal ``config`` file so as to provide a default set of
    partial constraints to be used by projects, providing a way for
    users to peg themselves to stable package collections.
976 977 978

.. option:: --enable-optimization[=n] or -O [n]

979 980 981 982 983 984
    (default) Build with optimization flags (if available). This is
    appropriate for production use, taking more time to build faster
    libraries and programs.

    The optional *n* value is the optimisation level. Some compilers
    support multiple optimisation levels. The range is 0 to 2. Level 0
985 986 987 988 989
    is equivalent to :option:`--disable-optimization`, level 1 is the
    default if no *n* parameter is given. Level 2 is higher optimisation
    if the compiler supports it. Level 2 is likely to lead to longer
    compile times and bigger generated code.

990 991
    When optimizations are enabled, Cabal passes ``-O2`` to the C compiler.

992
.. option:: --disable-optimization
993 994 995 996

    Build without optimization. This is suited for development: building
    will be quicker, but the resulting library or programs will be
    slower.
997 998 999

.. option:: --enable-profiling

1000 1001 1002 1003 1004 1005 1006 1007 1008
    Build libraries and executables with profiling enabled (for
    compilers that support profiling as a separate mode). For this to
    work, all libraries used by this package must also have been built
    with profiling support. For libraries this involves building an
    additional instance of the library in addition to the normal
    non-profiling instance. For executables it changes the single
    executable to be built in profiling mode.

    This flag covers both libraries and executables, but can be
1009 1010 1011
    overridden by the :option:`--enable-library-profiling` flag.

    See also the :option:`--profiling-detail` flag below.
1012

1013
.. option:: --disable-profiling
1014 1015 1016

    (default) Do not enable profiling in generated libraries and
    executables.
1017 1018 1019 1020

.. option:: --enable-library-profiling or -p

    As with :option:`--enable-profiling` above, but it applies only for
1021 1022 1023
    libraries. So this generates an additional profiling instance of the
    library in addition to the normal non-profiling instance.

1024
    The :option:`--enable-profiling` flag controls the profiling mode for both
1025
    libraries and executables, but if different modes are desired for
1026
    libraries versus executables then use :option:`--enable-library-profiling`
1027 1028
    as well.

1029 1030 1031 1032 1033 1034
.. option:: --disable-library-profiling

    (default) Do not generate an additional profiling version of the library.

.. option:: --profiling-detail[=level]

1035 1036 1037 1038 1039 1040 1041
    Some compilers that support profiling, notably GHC, can allocate
    costs to different parts of the program and there are different
    levels of granularity or detail with which this can be done. In
    particular for GHC this concept is called "cost centers", and GHC
    can automatically add cost centers, and can do so in different ways.

    This flag covers both libraries and executables, but can be
1042
    overridden by the :option:`--library-profiling-detail` flag.
1043 1044 1045 1046

    Currently this setting is ignored for compilers other than GHC. The
    levels that cabal currently supports are:

1047
    default
1048 1049
        For GHC this uses ``exported-functions`` for libraries and
        ``toplevel-functions`` for executables.
1050
    none
1051
        No costs will be assigned to any code within this component.
1052
    exported-functions
1053 1054 1055
        Costs will be assigned at the granularity of all top level
        functions exported from each module. In GHC specifically, this
        is for non-inline functions.
1056
    toplevel-functions
1057 1058 1059 1060
        Costs will be assigned at the granularity of all top level
        functions in each module, whether they are exported from the
        module or not. In GHC specifically, this is for non-inline
        functions.
1061
    all-functions
1062 1063 1064 1065 1066 1067 1068 1069
        Costs will be assigned at the granularity of all functions in
        each module, whether top level or local. In GHC specifically,
        this is for non-inline toplevel or where-bound functions or
        values.

    This flag is new in Cabal-1.24. Prior versions used the equivalent
    of ``none`` above.

1070 1071 1072
.. option:: --library-profiling-detail[=level]

    As with :option:`--profiling-detail` above, but it applies only for
1073 1074 1075
    libraries.

    The level for both libraries and executables is set by the
1076 1077 1078 1079 1080
    :option:`--profiling-detail` flag, but if different levels are desired
    for libraries versus executables then use
    :option:`--library-profiling-detail` as well.

.. option:: --enable-library-vanilla
1081 1082 1083

    (default) Build ordinary libraries (as opposed to profiling
    libraries). This is independent of the
1084
    :option:`--enable-library-profiling` option. If you enable both, you get
1085
    both.
1086 1087 1088

.. option:: --disable-library-vanilla

1089
    Do not build ordinary libraries. This is useful in conjunction with
1090
    :option:`--enable-library-profiling` to build only profiling libraries,
1091
    rather than profiling and ordinary libraries.
1092 1093 1094

.. option:: --enable-library-for-ghci

1095
    (default) Build libraries suitable for use with GHCi.
1096 1097 1098

.. option:: --disable-library-for-ghci

1099 1100 1101
    Not all platforms support GHCi and indeed on some platforms, trying
    to build GHCi libs fails. In such cases this flag can be used as a
    workaround.
1102 1103 1104

.. option:: --enable-split-objs

1105 1106 1107 1108 1109
    Use the GHC ``-split-objs`` feature when building the library. This
    reduces the final size of the executables that use the library by
    allowing them to link with only the bits that they use rather than
    the entire library. The downside is that building the library takes
    longer and uses considerably more memory.
1110 1111 1112

.. option:: --disable-split-objs

1113 1114 1115
    (default) Do not use the GHC ``-split-objs`` feature. This makes
    building the library quicker but the final executables that use the
    library will be larger.
1116 1117 1118

.. option:: --enable-executable-stripping

1119 1120 1121 1122 1123 1124 1125 1126 1127 1128
    (default) When installing binary executable programs, run the
    ``strip`` program on the binary. This can considerably reduce the
    size of the executable binary file. It does this by removing
    debugging information and symbols. While such extra information is
    useful for debugging C programs with traditional debuggers it is
    rarely helpful for debugging binaries produced by Haskell compilers.

    Not all Haskell implementations generate native binaries. For such
    implementations this option has no effect.

1129 1130
.. option:: --disable-executable-stripping

1131 1132 1133 1134 1135 1136
    Do not strip binary executables during installation. You might want
    to use this option if you need to debug a program using gdb, for
    example if you want to debug the C parts of a program containing
    both Haskell and C code. Another reason is if your are building a
    package for a system which has a policy of managing the stripping
    itself (such as some Linux distributions).
1137 1138 1139

.. option:: --enable-shared

1140 1141
    Build shared library. This implies a separate compiler run to
    generate position independent code as required on most platforms.
1142 1143 1144

.. option:: --disable-shared

1145
    (default) Do not build shared library.
1146

Moritz Angermann's avatar
Moritz Angermann committed
1147 1148
.. option:: --enable-static

vedksah's avatar
vedksah committed
1149
   Build a static library. This passes ``-staticlib`` to GHC (available
Moritz Angermann's avatar
Moritz Angermann committed
1150 1151 1152 1153 1154 1155 1156
   for iOS, and with 8.4 more platforms).  The result is an archive ``.a``
   containing all dependent haskell libararies combined.

.. option:: --disable-static

    (default) Do not build a static library.

1157 1158
.. option:: --enable-executable-dynamic

1159
    Link executables dynamically. The executable's library dependencies
1160 1161 1162 1163 1164 1165 1166 1167 1168
    should be built as shared objects. This implies :option:`--enable-shared`
    unless :option:`--disable-shared` is explicitly specified.

.. option:: --disable-executable-dynamic

   (default) Link executables statically.

.. option:: --configure-option=str

1169 1170 1171 1172
    An extra option to an external ``configure`` script, if one is used
    (see the section on `system-dependent
    parameters <developing-packages.html#system-dependent-parameters>`__).
    There can be several of these options.
1173 1174 1175

.. option:: --extra-include-dirs[=dir]

1176 1177 1178 1179 1180 1181 1182 1183 1184 1185 1186 1187 1188
    An extra directory to search for C header files. You can use this
    flag multiple times to get a list of directories.

    You might need to use this flag if you have standard system header
    files in a non-standard location that is not mentioned in the
    package's ``.cabal`` file. Using this option has the same affect as
    appending the directory *dir* to the ``include-dirs`` field in each
    library and executable in the package's ``.cabal`` file. The
    advantage of course is that you do not have to modify the package at
    all. These extra directories will be used while building the package
    and for libraries it is also saved in the package registration
    information and used when compiling modules that use the library.

1189 1190
.. option:: --extra-lib-dirs[=dir]

1191 1192
    An extra directory to search for system libraries files. You can use
    this flag multiple times to get a list of directories.
1193 1194 1195

.. option:: --extra-framework-dirs[=dir]

1196 1197 1198 1199 1200 1201 1202 1203 1204 1205 1206 1207 1208
    An extra directory to search for frameworks (OS X only). You can use
    this flag multiple times to get a list of directories.

    You might need to use this flag if you have standard system
    libraries in a non-standard location that is not mentioned in the
    package's ``.cabal`` file. Using this option has the same affect as
    appending the directory *dir* to the ``extra-lib-dirs`` field in
    each library and executable in the package's ``.cabal`` file. The
    advantage of course is that you do not have to modify the package at
    all. These extra directories will be used while building the package
    and for libraries it is also saved in the package registration
    information and used when compiling modules that use the library.

1209 1210
.. option:: --dependency[=pkgname=ipid]

1211 1212 1213
    Specify that a particular dependency should used for a particular
    package name. In particular, it declares that any reference to
    *pkgname* in a ``build-depends`` should be resolved to *ipid*.
1214 1215 1216

.. option:: --exact-configuration

1217
    This changes Cabal to require every dependency be explicitly
1218
    specified using :option:`--dependency`, rather than use Cabal's (very
1219 1220
    simple) dependency solver. This is useful for programmatic use of
    Cabal's API, where you want to error if you didn't specify enough