docs/users_guide/7.0.1-notes.xml

   1 <?xml version="1.0" encoding="iso-8859-1"?>
   2 <sect1 id="release-7-0-1">
   3   <title>Release notes for version 7.0.1</title>
   4
   5   <para>
   6     The significant changes to the various parts of the compiler are
   7     listed in the following sections. There have also been numerous bug
   8     fixes and performance improvements over the 6.12 branch.
   9   </para>
  10
  11   <sect2>
  12     <title>Highlights</title>
  13     <itemizedlist>
  14       <listitem>
  15         <para>
  16           GHC now defaults to the Haskell 2010 language standard.
  17         </para>
  18
  19         <para>
  20           Libraries are not quite so straightforward.  By default, GHC
  21           provides access to the <literal>base</literal> package,
  22           which includes the Haskell 2010 libraries, albeit with a few
  23           minor differences.  For those who want to write strictly
  24           standards-conforming code we also provide
  25           the <literal>haskell2010</literal> package which provides
  26           the precise APIs specified by Haskell 2010, but because the
  27           module names in this package overlap with those in
  28           the <literal>base</literal> package it is not possible to
  29           use both <literal>haskell2010</literal>
  30           and <literal>base</literal> at the same time (this also
  31           applies to the <literal>array</literal> package).  Hence to use
  32           the Haskell 2010 libraries you should hide
  33           the <literal>base</literal> and <literal>array</literal>
  34           packages, for example with GHCi:
  35 <screen>
  36 $ ghci -package haskell2010 -hide-package base -hide-package array
  37 </screen>
  38           If you are using Cabal it isn't necessary to
  39           hide <literal>base</literal> and <literal>array</literal>
  40           explicitly, just don't include them in your <literal>build-depends</literal>.
  41         </para>
  42       </listitem>
  43
  44       <listitem>
  45         <para>
  46           On POSIX platforms, there is a new I/O manager based on
  47           epoll/kqueue/poll, which allows multithreaded I/O code to
  48           scale to a much larger number (100k+) of threads.
  49         </para>
  50       </listitem>
  51
  52       <listitem>
  53         <para>
  54                                         GHC now includes an LLVM code generator. For certain code,
  55                                         particularly arithmetic heavy code, using the LLVM code
  56                                         generator can bring some nice performance improvements.
  57         </para>
  58       </listitem>
  59
  60       <listitem>
  61         <para>
  62           The type checker has been overhauled, which means it is now
  63           able to correctly handle interactions between the type system
  64           extensions.
  65         </para>
  66       </listitem>
  67
  68       <listitem>
  69         <para>
  70           The inliner has been overhauled, which should in general
  71           give better performance while reducing unnecessary code-size
  72           explosion.
  73         </para>
  74       </listitem>
  75
  76       <listitem>
  77         <para>
  78           Large parts of the runtime system have been overhauled, in
  79           particular the machinery related to blocking and wakeup of
  80           threads and exception throwing (<literal>throwTo</literal>).
  81           Several instances of pathological performance have been
  82           fixed, especially where large numbers of threads are
  83           involved.
  84         </para>
  85       </listitem>
  86
  87       <listitem>
  88         <para>
  89           Due to changes in the runtime system, if you are
  90           using <literal>Control.Parallel.Strategies</literal> from
  91           the <literal>parallel</literal> package, please upgrade to
  92           at least version 2 (preferably version 3).  The
  93           implementation of Strategies
  94           in <literal>parallel-1.x</literal> will lose parallelism
  95           with GHC 7.0.1.
  96         </para>
  97       </listitem>
  98
  99       <listitem>
 100         <para>
 101           The full Haskell <literal>import</literal> syntax can now been
 102           used to bring modules into scope in GHCi, e.g.
 103         </para>
 104 <programlisting>
 105 Prelude> import Data.List as L
 106 Prelude Data.List> L.length "foo"
 107 3
 108 </programlisting>
 109       </listitem>
 110
 111       <listitem>
 112         <para>
 113           GHC now comes with a more recent mingw bundled on Windows,
 114           which includes a fix for windres on Windows 7.
 115         </para>
 116       </listitem>
 117     </itemizedlist>
 118   </sect2>
 119
 120   <sect2>
 121     <title>Language changes</title>
 122     <itemizedlist>
 123       <listitem>
 124         <para>
 125           GHC now understands the <literal>Haskell98</literal> and
 126           <literal>Haskell2010</literal> languages.
 127         </para>
 128
 129         <para>
 130           These get processed before the language extension pragmas,
 131           and define the default sets of extensions that are enabled.
 132           If neither is specified, then the default is
 133           <literal>Haskell2010</literal> plus the
 134           <literal>MonoPatBinds</literal> extension.
 135         </para>
 136       </listitem>
 137
 138       <listitem>
 139         <para>
 140           GHC now supports the <literal>DoAndIfThenElse</literal>
 141           extension, which is part of the Haskell 2010 standard.
 142         </para>
 143       </listitem>
 144
 145       <listitem>
 146         <para>
 147           Datatype contexts, such as the <literal>Eq a</literal> in
 148         </para>
 149 <programlisting>
 150 data Eq a => Set a = NilSet | ConsSet a (Set a)
 151 </programlisting>
 152         <para>
 153           are now treated as an extension
 154           <literal>DatatypeContexts</literal> (on by default) by GHC.
 155         </para>
 156       </listitem>
 157
 158       <listitem>
 159         <para>
 160           GHC's support for unicode source has been improved, including
 161           removing support for U+22EF for the <literal>..</literal>
 162           symbol. See <xref linkend="unicode-syntax" /> for more details.
 163         </para>
 164       </listitem>
 165
 166       <listitem>
 167         <para>
 168           Pragmas are now reread after preprocessing. In particular,
 169           this means that if a pragma is used to turn CPP on, then other
 170           pragmas can be put in CPP conditionals.
 171         </para>
 172       </listitem>
 173
 174       <listitem>
 175         <para>
 176           The <literal>TypeOperators</literal> extension now allows
 177           instance heads to use infix syntax.
 178         </para>
 179       </listitem>
 180
 181       <listitem>
 182         <para>
 183           The <literal>PackageImports</literal> extension now understands
 184           <literal>this</literal> to mean the current package.
 185         </para>
 186       </listitem>
 187
 188       <listitem>
 189         <para>
 190           The <literal>INLINE</literal> and <literal>NOINLINE</literal>
 191           pragmas can now take a <literal>CONLIKE</literal> modifier,
 192           which indicates that the right hand side is cheap to compute,
 193           and can thus be duplicated more freely.
 194           See <xref linkend="conlike" /> for more details.
 195         </para>
 196       </listitem>
 197
 198       <listitem>
 199         <para>
 200           A <literal>ForceSpecConstr</literal> annotation on a type, e.g.
 201         </para>
 202 <programlisting>
 203 import SpecConstr
 204 {-# ANN type SPEC ForceSpecConstr #-}
 205 </programlisting>
 206         <para>
 207           can be used to force GHC to fully specialise argument of that
 208           type.
 209         </para>
 210       </listitem>
 211
 212       <listitem>
 213         <para>
 214           A <literal>NoSpecConstr</literal> annotation on a type, e.g.
 215         </para>
 216 <programlisting>
 217 import SpecConstr
 218 {-# ANN type T NoSpecConstr #-}
 219 </programlisting>
 220         <para>
 221           can be used to prevent SpecConstr from specialising on
 222           arguments of that type.
 223         </para>
 224       </listitem>
 225
 226       <listitem>
 227         <para>
 228           There is are two experimental new extensions
 229           <literal>AlternativeLayoutRule</literal> and
 230           <literal>AlternativeLayoutRuleTransitional</literal>,
 231           which are for exploring alternative layout rules in Haskell'.
 232           The details are subject to change, so we advise against using
 233           them in real code for now.
 234         </para>
 235       </listitem>
 236
 237       <listitem>
 238         <para>
 239           The <literal>NewQualifiedOperators</literal> extension has
 240           been deprecated, as it was rejected by the Haskell' committee.
 241         </para>
 242       </listitem>
 243     </itemizedlist>
 244   </sect2>
 245
 246   <sect2>
 247     <title>Warnings</title>
 248     <itemizedlist>
 249       <listitem>
 250         <para>
 251           There is now a warning for missing import lists, controlled
 252           by the new <literal>-fwarn-missing-import-lists</literal> flag.
 253         </para>
 254       </listitem>
 255
 256       <listitem>
 257         <para>
 258           GHC will now warn about <literal>SPECIALISE</literal> and
 259           <literal>UNPACK</literal> pragmas that have no effect.
 260         </para>
 261       </listitem>
 262     </itemizedlist>
 263   </sect2>
 264
 265   <sect2>
 266     <title>DLLs</title>
 267     <itemizedlist>
 268       <listitem>
 269         <para>
 270           Shared libraries are once again supported on Windows.
 271         </para>
 272       </listitem>
 273
 274       <listitem>
 275         <para>
 276           Shared libraries are now supported on OS X, both on x86 and on
 277           PowerPC. The new <literal>-dylib-install-name</literal> GHC
 278           flag is used to set the location of the dynamic library.
 279           See <xref linkend="finding-shared-libs" /> for more details.
 280         </para>
 281       </listitem>
 282     </itemizedlist>
 283   </sect2>
 284
 285   <sect2>
 286     <title>Runtime system</title>
 287
 288     <itemizedlist>
 289       <listitem>
 290         <para>
 291           For security reasons, by default, the only RTS flag that
 292           programs accept is <literal>+RTS --info</literal>. If you want
 293           the full range of RTS flags then you need to link with the new
 294           <literal>-rtsopts</literal> flag. See
 295           <xref linkend="options-linker" /> for more details.
 296         </para>
 297       </listitem>
 298
 299       <listitem>
 300         <para>
 301           The RTS now exports a function <literal>setKeepCAFs</literal>
 302           which is important when loading Haskell DLLs dynamically, as
 303           a DLL may refer to CAFs that hae already been GCed.
 304         </para>
 305       </listitem>
 306
 307       <listitem>
 308         <para>
 309           The garbage collector no longer allows you to specify a number
 310           of steps; there are now always 2. The <literal>-T</literal>
 311           RTS flag has thus been removed.
 312         </para>
 313       </listitem>
 314
 315       <listitem>
 316         <para>
 317           A new RTS flag <literal>-H</literal> causes the RTS to use a
 318           larger nursery, but without exceeding the amount of memory
 319           that the application is already using. It makes some programs
 320           go slower, but others go faster.
 321         </para>
 322       </listitem>
 323
 324       <listitem>
 325         <para>
 326           GHC now returns memory to the OS, if memory usage peaks and
 327           then drops again. This is mainly useful for long running
 328           processes which normally use very little memory, but
 329           occasionally need a lot of memory for a short period of time.
 330         </para>
 331       </listitem>
 332
 333       <listitem>
 334         <para>
 335           On OS X, eventLog events are now available as DTrace probes.
 336         </para>
 337       </listitem>
 338
 339       <listitem>
 340         <para>
 341           The PAPI support has been improved. The new RTS flag
 342           <literal>-a#0x40000000</literal> can be used to tell the RTS
 343           to collect the native PAPI event <literal>0x40000000</literal>.
 344         </para>
 345       </listitem>
 346     </itemizedlist>
 347   </sect2>
 348
 349   <sect2>
 350     <title>Compiler</title>
 351     <itemizedlist>
 352       <listitem>
 353         <para>
 354           GHC now defaults to <literal>--make</literal> mode, i.e. GHC
 355           will chase dependencies for you automatically by default.
 356         </para>
 357       </listitem>
 358
 359       <listitem>
 360         <para>
 361           GHC now includes an LLVM code generator.
 362         </para>
 363         <para>
 364           This includes a number of new flags:
 365           a flag to tell GHC to use LLVM, <literal>-fllvm</literal>;
 366           a flag to dump the LLVM input ,<literal>-ddump-llvm</literal>;
 367           flags to keep the LLVM intermediate files,
 368           <literal>-keep-llvm-file</literal> and
 369           <literal>-keep-llvm-files</literal>;
 370                                         flags to set the location and options for the LLVM optimiser
 371                                         and compiler,
 372           <literal>-pgmlo</literal>,
 373           <literal>-pgmlc</literal>,
 374           <literal>-optlo</literal> and
 375           <literal>-optlc</literal>.
 376                                         The LLVM code generator requires LLVM version 2.7 or later on
 377                                         your path.
 378         </para>
 379       </listitem>
 380
 381       <listitem>
 382         <para>
 383           It is now possible to use <literal>-fno-code</literal> with
 384           <literal>--make</literal>.
 385         </para>
 386       </listitem>
 387
 388       <listitem>
 389         <para>
 390           The new flag <literal>-dsuppress-coercions</literal> controls
 391           whether GHC prints coercions in core dumps.
 392         </para>
 393       </listitem>
 394
 395       <listitem>
 396         <para>
 397           The new flag <literal>-dsuppress-module-prefixes</literal>
 398           controls whether GHC prints module qualification prefixes
 399           in core dumps.
 400         </para>
 401       </listitem>
 402
 403       <listitem>
 404         <para>
 405           The inliner has been overhauled. The most significant
 406           user-visible change is that only saturated functions are
 407           inlined, e.g.
 408         </para>
 409 <programlisting>
 410 (.) f g x = f (g x)
 411 </programlisting>
 412         <para>
 413           would only be inlined if <literal>(.)</literal> is applied to 3
 414           arguments, while
 415         </para>
 416 <programlisting>
 417 (.) f g = \x -> f (g x)
 418 </programlisting>
 419         <para>
 420           will be inlined if only applied to 2 arguments.
 421         </para>
 422       </listitem>
 423
 424       <listitem>
 425         <para>
 426           The <literal>-finline-if-enough-args</literal> flag is no
 427           longer supported.
 428         </para>
 429       </listitem>
 430
 431       <listitem>
 432         <para>
 433           Column numbers in warnings and error messages now start at 1,
 434           as is more standard, rather than 0.
 435         </para>
 436       </listitem>
 437
 438       <listitem>
 439         <para>
 440           GHCi now understands most linker scripts. In particular, this
 441           means that GHCi is able to load the C pthread library.
 442         </para>
 443       </listitem>
 444
 445       <listitem>
 446         <para>
 447           The <literal>ghc --info</literal> output has been updated:
 448         </para>
 449         <para>
 450           It now includes the
 451           location of the global package database, in the
 452           <literal>Global Package DB</literal> field.
 453         </para>
 454         <para>
 455           It now includes the build, host and target platforms, in the
 456           <literal>Build platform</literal>,
 457           <literal>Host platform</literal> and
 458           <literal>Target platform</literal> fields.
 459         </para>
 460         <para>
 461           It now includes a <literal>Have llvm code generator</literal>
 462           field.
 463         </para>
 464         <para>
 465           The <literal>Win32 DLLs</literal> field has been removed.
 466         </para>
 467       </listitem>
 468
 469       <listitem>
 470         <para>
 471           The registerised via-C backend, and the
 472           <literal>-fvia-C</literal> flag, have been deprecated. The poor
 473           floating-point performance in the x86 native code generator
 474           has now been fixed, so we don't believe there is still any
 475           reason to use the via-C backend.
 476         </para>
 477       </listitem>
 478
 479       <listitem>
 480         <para>
 481           There is now a new flag <literal>--supported-extensions</literal>,
 482           which currently behaves the same as
 483           <literal>--supported-languages</literal>.
 484         </para>
 485       </listitem>
 486
 487       <listitem>
 488         <para>
 489           GHC progress output such as
 490         </para>
 491 <programlisting>
 492 [ 1 of 5] Compiling Foo              ( Foo.hs, Foo.o )
 493 </programlisting>
 494         <para>
 495           is now sent to stdout rather than stderr.
 496         </para>
 497       </listitem>
 498
 499       <listitem>
 500         <para>
 501           The new flag <literal>-fexpose-all-unfoldings</literal>
 502           makes GHC put unfoldings for <emphasis>everything</emphasis>
 503           in the interface file.
 504         </para>
 505       </listitem>
 506
 507       <listitem>
 508         <para>
 509           There are two new flags, <literal>-fno-specialise</literal>
 510           and <literal>-fno-float-in</literal>, for disabling the
 511           specialise and float-in passes.
 512         </para>
 513       </listitem>
 514
 515       <listitem>
 516         <para>
 517           The new flag <literal>-fstrictness-before=<replaceable>n</replaceable></literal> tells
 518           GHC to run an additional strictness analysis pass
 519           before simplifier phase <replaceable>n</replaceable>.
 520         </para>
 521       </listitem>
 522
 523       <listitem>
 524         <para>
 525           There is a new flag
 526           <literal>-funfolding-dict-discount</literal>
 527           for tweaking the optimiser's behaviour.
 528         </para>
 529       </listitem>
 530
 531       <listitem>
 532         <para>
 533           The <literal>-fspec-inline-join-points</literal> flag has been
 534           removed.
 535         </para>
 536       </listitem>
 537
 538       <listitem>
 539         <para>
 540           The <literal>-dynload wrapper</literal> flag has been
 541           removed.
 542         </para>
 543       </listitem>
 544     </itemizedlist>
 545   </sect2>
 546
 547   <sect2>
 548     <title>GHCi</title>
 549     <itemizedlist>
 550       <listitem>
 551         <para>
 552           GHCi now understands layout in multi-line commands, so
 553           this now works:
 554         </para>
 555 <programlisting>
 556 Prelude> :{
 557 Prelude| let x = 1
 558 Prelude|     y = 2 in x + y
 559 Prelude| :}
 560 3
 561 </programlisting>
 562       </listitem>
 563     </itemizedlist>
 564   </sect2>
 565
 566   <sect2>
 567     <title>Template Haskell and Quasi-Quoters</title>
 568     <itemizedlist>
 569       <listitem>
 570         <para>
 571           It is now possible to quasi-quote patterns with
 572           <literal>[p| ... |]</literal>.
 573         </para>
 574       </listitem>
 575
 576       <listitem>
 577         <para>
 578           It is no longer to use a <literal>$</literal> before the
 579           name of a quasi-quoter, e.g. one can now say
 580           <literal>[expr| ... |]</literal> rather than
 581           <literal>[$expr| ... |]</literal>.
 582         </para>
 583       </listitem>
 584
 585       <listitem>
 586         <para>
 587           It is now possible to use a quasi-quoter for types, e.g.
 588           <literal>f :: [$qq| ... |]</literal>
 589         </para>
 590       </listitem>
 591
 592       <listitem>
 593         <para>
 594           It is now possible to quasi-quote existentials and GADTs.
 595         </para>
 596       </listitem>
 597     </itemizedlist>
 598   </sect2>
 599
 600   <sect2>
 601     <title>GHC API</title>
 602     <itemizedlist>
 603       <listitem>
 604         <para>
 605           There are now <literal>Data</literal> and
 606           <literal>Typeable</literal> instances for the
 607           HsSyn typed.
 608         </para>
 609       </listitem>
 610
 611       <listitem>
 612         <para>
 613           As language extensions are not applied until after the base
 614           language (Haskell98, Haskell2010 or the default) has been
 615           selected, it is now necessary to tell the GHC API the point
 616           at which the extension flags should be processed. Normally
 617           this is done by calling
 618           <literal>DynFlags.flattenExtensionFlags</literal> once all
 619           the flags and pragmas have been read.
 620         </para>
 621       </listitem>
 622     </itemizedlist>
 623   </sect2>
 624
 625   <sect2>
 626     <title>Libraries</title>
 627
 628     <sect3>
 629         <title>array</title>
 630         <itemizedlist>
 631             <listitem>
 632                 <para>
 633                     Version number 0.3.0.2 (was 0.3.0.1)
 634                 </para>
 635             </listitem>
 636         </itemizedlist>
 637     </sect3>
 638
 639     <sect3>
 640         <title>base</title>
 641         <itemizedlist>
 642             <listitem>
 643                 <para>
 644                     Version number 4.3.0.0 (was 4.2.0.2)
 645                 </para>
 646             </listitem>
 647
 648             <listitem>
 649                 <para>
 650                     There is a new asynchronous exception control API
 651                     in <literal>Control.Exception</literal>, using the
 652                     new functions
 653                     <literal>mask :: ((forall a. IO a -> IO a) -> IO b) -> IO b</literal>
 654                     and <literal>mask_ :: IO a -> IO a</literal>
 655                     rather than the old
 656                     <literal>block</literal> and <literal>unblock</literal>.
 657                     There are also functions
 658                     <literal>uninterruptibleMask :: ((forall a. IO a -> IO a) -> IO b) -> IO b</literal>
 659                     and
 660                     <literal>getMaskingState :: IO MaskingState</literal>,
 661                     and a type
 662                     <literal>MaskingState</literal>, as well as
 663                     <literal>forkIOUnmasked :: IO () -> IO ThreadId</literal>
 664                     in <literal>Control.Concurrent</literal>.
 665                 </para>
 666             </listitem>
 667
 668             <listitem>
 669                 <para>
 670                     <literal>Control.Monad</literal> exports a new function
 671                     <literal>void :: Functor f => f a -> f ()</literal>.
 672                 </para>
 673             </listitem>
 674
 675             <listitem>
 676                 <para>
 677                     <literal>Data.Tuple</literal> exports a new function
 678                     <literal>swap :: (a,b) -> (b,a)</literal>.
 679                 </para>
 680             </listitem>
 681
 682             <listitem>
 683                 <para>
 684                     <literal>System.IO</literal> exports a new function
 685                     <literal>hGetBufSome :: Handle -> Ptr a -> Int -> IO Int</literal>
 686                     which is like <literal>hGetBuf</literal> but can
 687                     return short reads.
 688                 </para>
 689             </listitem>
 690
 691             <listitem>
 692                 <para>
 693                     There is a new function
 694                     <literal>mfilter :: MonadPlus m => (a -> Bool) -> m a -> m a</literal>
 695                     in
 696                     <literal>Control.Monad</literal>.
 697                 </para>
 698             </listitem>
 699
 700             <listitem>
 701                 <para>
 702                     The <literal>Foreign.Marshal</literal> module now
 703                     exports
 704                     <literal>unsafeLocalState :: IO a -> a</literal>
 705                     as specified by Haskell 2010.
 706                 </para>
 707             </listitem>
 708
 709             <listitem>
 710                 <para>
 711                     The <literal></literal>
 712                     module now exports four new functions specified by
 713                     Haskell 2010:
 714                     <literal>castCUCharToChar :: CUChar -> Char</literal>,
 715                     <literal>castCharToCUChar :: Char -> CUChar</literal>,
 716                     <literal>castCSCharToChar :: CSChar -> Char</literal> and
 717                     <literal>castCharToCSChar :: Char -> CSChar</literal>.
 718                 </para>
 719             </listitem>
 720
 721             <listitem>
 722                 <para>
 723                     The <literal>Foreign.Marshal.Alloc</literal>
 724                     module now exports
 725                     <literal>allocaBytesAligned :: Int -> Int -> (Ptr a -> IO b) -> IO b</literal>
 726                     for allocating memory with a particular alignment.
 727                 </para>
 728             </listitem>
 729
 730             <listitem>
 731                 <para>
 732                     There is a new function
 733                     <literal>numSparks :: IO Int</literal>
 734                     in <literal>GHC.Conc</literal>.
 735                 </para>
 736             </listitem>
 737
 738             <listitem>
 739                 <para>
 740                     <literal>Data.Either.partitionEithers</literal>
 741                     in now lazier.
 742                 </para>
 743             </listitem>
 744
 745             <listitem>
 746                 <para>
 747                     There is now a <literal>Typeable</literal> instance for
 748                     <literal>Data.Unique.Unique</literal>.
 749                 </para>
 750             </listitem>
 751
 752             <listitem>
 753                 <para>
 754                     <literal>Control.Concurrent.SampleVar.SampleVar</literal>
 755                     is now an abstract type.
 756                 </para>
 757             </listitem>
 758
 759             <listitem>
 760                 <para>
 761                     There are now
 762                     <literal>Applicative</literal>,
 763                     <literal>Alternative</literal> and
 764                     <literal>MonadPlus</literal>
 765                     instances for <literal>STM</literal>.
 766                 </para>
 767             </listitem>
 768
 769             <listitem>
 770                 <para>
 771                     There are now <literal>Applicative</literal>,
 772                     <literal>Monad</literal> and
 773                     <literal>MonadFix</literal>
 774                     instances for <literal>Either</literal>.
 775                 </para>
 776             </listitem>
 777
 778             <listitem>
 779                 <para>
 780                     There are now
 781                     <literal>Ord</literal>,
 782                     <literal>Read</literal> and
 783                     <literal>Show</literal> instances for
 784                     <literal>Newline</literal> and
 785                     <literal>NewlineMode</literal>.
 786                 </para>
 787             </listitem>
 788
 789             <listitem>
 790                 <para>
 791                     There is now a <literal>Show</literal> instance for
 792                     <literal>TextEncoding</literal>.
 793                 </para>
 794             </listitem>
 795
 796             <listitem>
 797                 <para>
 798                     The <literal>unGetChan</literal> and
 799                     <literal>isEmptyChan</literal> functions in
 800                     <literal>Control.Concurrent.Chan</literal> are now
 801                     deprecated.
 802                     <literal>Control.Concurrent.STM.TChan</literal>
 803                     should be used instead if you need that
 804                     functionality.
 805                 </para>
 806             </listitem>
 807
 808             <listitem>
 809                 <para>
 810                     The <literal>Read Integer</literal> instance now
 811                     matches the standard definition.
 812                 </para>
 813             </listitem>
 814         </itemizedlist>
 815     </sect3>
 816
 817     <sect3>
 818         <title>base 3 compat</title>
 819         <itemizedlist>
 820             <listitem>
 821                 <para>
 822                     We no longer ship a base 3 compat package
 823                 </para>
 824             </listitem>
 825         </itemizedlist>
 826     </sect3>
 827
 828     <sect3>
 829         <title>bin-package-db</title>
 830         <itemizedlist>
 831             <listitem>
 832                 <para>
 833                     This is an internal package, and should not be used.
 834                 </para>
 835             </listitem>
 836         </itemizedlist>
 837     </sect3>
 838
 839     <sect3>
 840         <title>bytestring</title>
 841         <itemizedlist>
 842             <listitem>
 843                 <para>
 844                     Version number 0.9.1.8 (was 0.9.1.7)
 845                 </para>
 846             </listitem>
 847         </itemizedlist>
 848     </sect3>
 849
 850     <sect3>
 851         <title>Cabal</title>
 852         <itemizedlist>
 853             <listitem>
 854                 <para>
 855                     Version number 1.9.2 (was 1.8.0.6)
 856                 </para>
 857             </listitem>
 858
 859             <listitem>
 860                 <para>
 861                     Many API changes. See the Cabal docs for more information.
 862                 </para>
 863             </listitem>
 864         </itemizedlist>
 865     </sect3>
 866
 867     <sect3>
 868         <title>containers</title>
 869         <itemizedlist>
 870             <listitem>
 871                 <para>
 872                     Version number 0.4.0.0 (was 0.3.0.0)
 873                 </para>
 874             </listitem>
 875
 876             <listitem>
 877                 <para>
 878                     Strictness is now more consistent, with containers
 879                     being strict in their elements even in singleton
 880                     cases.
 881                 </para>
 882             </listitem>
 883
 884             <listitem>
 885                 <para>
 886                     There is a new function
 887                     <literal>insertLookupWithKey'</literal> in
 888                     <literal>Data.Map</literal>.
 889                 </para>
 890             </listitem>
 891
 892             <listitem>
 893                 <para>
 894                     The <literal>foldWithKey</literal> function in
 895                     <literal>Data.Map</literal> has been deprecated in
 896                     favour of <literal>foldrWithKey</literal>.
 897                 </para>
 898             </listitem>
 899         </itemizedlist>
 900     </sect3>
 901
 902     <sect3>
 903         <title>directory</title>
 904         <itemizedlist>
 905             <listitem>
 906                 <para>
 907                     Version number 1.1.0.0 (was 1.0.1.1)
 908                 </para>
 909             </listitem>
 910
 911             <listitem>
 912                 <para>
 913                     The <literal>System.Directory</literal> module
 914                     now exports the <literal>Permissions</literal> type
 915                     abstractly. There are also new functions
 916                     <literal>setOwnerReadable</literal>,
 917                     <literal>setOwnerWritable</literal>,
 918                     <literal>setOwnerExecutable</literal> and
 919                     <literal>setOwnerSearchable</literal>, and
 920                     a new value <literal>emptyPermissions</literal>.
 921                 </para>
 922             </listitem>
 923         </itemizedlist>
 924     </sect3>
 925
 926     <sect3>
 927         <title>
 928             dph
 929             (dph-base, dph-par, dph-prim-interface, dph-prim-par,
 930             dph-prim-seq, dph-seq)
 931         </title>
 932         <itemizedlist>
 933             <listitem>
 934                 <para>
 935                     All the dph packages are version 0.4.0.
 936                 </para>
 937             </listitem>
 938         </itemizedlist>
 939     </sect3>
 940
 941     <sect3>
 942         <title>extensible-exceptions</title>
 943         <itemizedlist>
 944             <listitem>
 945                 <para>
 946                     Version number 0.1.1.2 (was 0.1.1.1)
 947                 </para>
 948             </listitem>
 949         </itemizedlist>
 950     </sect3>
 951
 952     <sect3>
 953         <title>filepath</title>
 954         <itemizedlist>
 955             <listitem>
 956                 <para>
 957                     Version number 1.2.0.0 (was 1.1.0.4)
 958                 </para>
 959             </listitem>
 960
 961             <listitem>
 962                 <para>
 963                     The current directory is now <literal>"."</literal>
 964                     rather than <literal>""</literal>.
 965                 </para>
 966             </listitem>
 967         </itemizedlist>
 968     </sect3>
 969
 970     <sect3>
 971         <title>ghc-binary</title>
 972         <itemizedlist>
 973             <listitem>
 974                 <para>
 975                     This is an internal package, and should not be used.
 976                 </para>
 977             </listitem>
 978         </itemizedlist>
 979     </sect3>
 980
 981     <sect3>
 982         <title>ghc-prim</title>
 983         <itemizedlist>
 984             <listitem>
 985                 <para>
 986                     This is an internal package, and should not be used.
 987                 </para>
 988             </listitem>
 989         </itemizedlist>
 990     </sect3>
 991
 992     <sect3>
 993         <title>haskell98</title>
 994         <itemizedlist>
 995             <listitem>
 996                 <para>
 997                     Version number 1.1.0.0 (was 1.0.1.1)
 998                 </para>
 999             </listitem>
1000
1001             <listitem>
1002                 <para>
1003                     In the <literal>Directory</literal> module, the
1004                     <literal>Permissions</literal> type and the
1005                     <literal>getPermissions</literal> and
1006                     <literal>setPermissions</literal> functions are now
1007                     different to their equivalents in
1008                     <literal>base:System.Directory</literal>.
1009                 </para>
1010             </listitem>
1011         </itemizedlist>
1012     </sect3>
1013
1014     <sect3>
1015         <title>haskell2010</title>
1016         <itemizedlist>
1017             <listitem>
1018                 <para>
1019                     This is a new boot package, version 1.0.0.0.
1020                     It is not exposed by default.
1021                 </para>
1022             </listitem>
1023         </itemizedlist>
1024     </sect3>
1025
1026     <sect3>
1027         <title>hpc</title>
1028         <itemizedlist>
1029             <listitem>
1030                 <para>
1031                     Version number 0.5.0.6 (was 0.5.0.5)
1032                 </para>
1033             </listitem>
1034         </itemizedlist>
1035     </sect3>
1036
1037     <sect3>
1038         <title>integer-gmp</title>
1039         <itemizedlist>
1040             <listitem>
1041                 <para>
1042                     Version number 0.2.0.2 (was 0.2.0.1)
1043                 </para>
1044             </listitem>
1045         </itemizedlist>
1046     </sect3>
1047
1048     <sect3>
1049         <title>old-locale</title>
1050         <itemizedlist>
1051             <listitem>
1052                 <para>
1053                     No change (version 1.0.0.2)
1054                 </para>
1055             </listitem>
1056         </itemizedlist>
1057     </sect3>
1058
1059     <sect3>
1060         <title>old-time</title>
1061         <itemizedlist>
1062             <listitem>
1063                 <para>
1064                     Version number 1.0.0.6 (was 1.0.0.5)
1065                 </para>
1066             </listitem>
1067         </itemizedlist>
1068     </sect3>
1069
1070     <sect3>
1071         <title>pretty</title>
1072         <itemizedlist>
1073             <listitem>
1074                 <para>
1075                     Version number 1.0.1.2 (was 1.0.1.1)
1076                 </para>
1077             </listitem>
1078         </itemizedlist>
1079     </sect3>
1080
1081     <sect3>
1082         <title>process</title>
1083         <itemizedlist>
1084             <listitem>
1085                 <para>
1086                     Version number 1.0.1.4 (was 1.0.1.3)
1087                 </para>
1088             </listitem>
1089         </itemizedlist>
1090     </sect3>
1091
1092     <sect3>
1093         <title>random</title>
1094         <itemizedlist>
1095             <listitem>
1096                 <para>
1097                     Version number 1.0.0.3 (was 1.0.0.2)
1098                 </para>
1099             </listitem>
1100         </itemizedlist>
1101     </sect3>
1102
1103     <sect3>
1104         <title>syb</title>
1105         <itemizedlist>
1106             <listitem>
1107                 <para>
1108                     The syb package is no longer included with GHC.
1109                 </para>
1110             </listitem>
1111         </itemizedlist>
1112     </sect3>
1113
1114     <sect3>
1115         <title>template-haskell</title>
1116         <itemizedlist>
1117             <listitem>
1118                 <para>
1119                     Version number 2.5.0.0 (was 2.4.0.1)
1120                 </para>
1121             </listitem>
1122
1123             <listitem>
1124                 <para>
1125                     There is a new type synonym <literal>DecsQ</literal>
1126                     in <literal>Language.Haskell.TH.Lib</literal>.
1127                 </para>
1128             </listitem>
1129
1130             <listitem>
1131                 <para>
1132                     There is a new <literal>StringPrimL</literal>
1133                     constructor in
1134                     <literal>Language.Haskell.TH.Syntax.Lit</literal>,
1135                     and a new helper function
1136                     <literal>stringPrimL</literal> for it in
1137                     <literal>Language.Haskell.TH.Lib</literal>.
1138                 </para>
1139             </listitem>
1140
1141             <listitem>
1142                 <para>
1143                     There is a new function <literal>quoteFile</literal>
1144                     in <literal>Language.Haskell.TH.Quote</literal>.
1145                 </para>
1146             </listitem>
1147
1148             <listitem>
1149                 <para>
1150                     The
1151                     <literal>Language.Haskell.TH.Quote.QuasiQuoter</literal>
1152                     type has two new fields:
1153                     <literal>quoteType</literal> and
1154                     <literal>quoteDec</literal>.
1155                 </para>
1156             </listitem>
1157
1158             <listitem>
1159                 <para>
1160                     There is a new <literal>ClassInstance</literal>
1161                     type in <literal>Language.Haskell.TH.Syntax</literal>.
1162                     The
1163                     <literal>Language.Haskell.TH.Syntax.Info.ClassI</literal>
1164                     constructor now includes a value of this type, which
1165                     allows instance information to be queried via the
1166                     new <literal>isClassInstance</literal>
1167                     and <literal>classInstances</literal> functions.
1168                     There is also a new method
1169                     <literal>qClassInstances</literal> in the
1170                     <literal>Quasi</literal> class.
1171                 </para>
1172             </listitem>
1173         </itemizedlist>
1174     </sect3>
1175
1176     <sect3>
1177         <title>time</title>
1178         <itemizedlist>
1179             <listitem>
1180                 <para>
1181                     Version number 1.2.0.3 (was 1.1.4)
1182                 </para>
1183             </listitem>
1184
1185             <listitem>
1186                 <para>
1187                     The types provided by the time package now include
1188                     <literal>Data</literal> instances.
1189                 </para>
1190             </listitem>
1191         </itemizedlist>
1192     </sect3>
1193
1194     <sect3>
1195         <title>unix</title>
1196         <itemizedlist>
1197             <listitem>
1198                 <para>
1199                     Version number 2.4.1.0 (was 2.4.0.2)
1200                 </para>
1201             </listitem>
1202
1203             <listitem>
1204                 <para>
1205                     There are three new helper function in
1206                     <literal>System.Posix.Error</literal>:
1207                     <literal>throwErrnoPathIfRetry</literal>,
1208                     <literal>throwErrnoPathIfNullRetry</literal> and
1209                     <literal>throwErrnoPathIfMinus1Retry</literal>.
1210                 </para>
1211             </listitem>
1212
1213             <listitem>
1214                 <para>
1215                     There are three new functions in
1216                     <literal>System.Posix.User</literal>:
1217                     <literal>setEffectiveUserID</literal>,
1218                     <literal>setEffectiveGroupID</literal> and
1219                     <literal>setGroups</literal>.
1220                 </para>
1221             </listitem>
1222         </itemizedlist>
1223     </sect3>
1224   </sect2>
1225 </sect1>
1226