[Caml-list] OCaml release 4.00.0

[Damien Doligez <damien.doligez@inria.fr>]

Dear OCaml users,

I have been rather busy preparing the new OCaml release, and
I had no time to go shopping for a birthday present for my wife.
So... here is a little present for her:


We have the pleasure of celebrating Laïka's birthday by
announcing the release of OCaml version 4.00.0.

This is a major release with many new features, the most
important being generalized algebraic data types (GADTs),
which by themselves justify bumping the major version number.

It is available here: < http://caml.inria.fr/download.en.html >

We also want to thank all the packagers out there who make
this easy to install for end users without recompiling.

Happy birthday,

-- Damien Doligez for the OCaml team.


------------------------------------------------------------------

There are a few changes between 4.00.0+rc1 and 4.00.0:

 - PR#5692: regression in 4.00.0+beta2: end locations wrong in camlp4 ast
 - PR#5694: crash in type-checker
 - PR#5696: ocamldep -native does not print bytecode deps and confuses omake
 - [Caml-list] #install_printer gives error in 4.00.0+rc1
 - As an unintended consequence of the previous fix, this
   release triggers the following warning in ocamlfind:

     findlib: [WARNING] Interface topdirs.cmi occurs in several directories:
     /usr/local/lib/ocaml, /usr/local/lib/ocaml/compiler-libs

   We will fix it in the future, but for the time being you
   can safely ignore this particular warning.
   

------------------------------------------------------------------

OCaml 4.00.0:
-------------

(Changes that can break existing programs are marked with a "*")

- The official name of the language is now OCaml.

Language features:
- Added Generalized Abstract Data Types (GADTs) to the language.
  See chapter "Language extensions" of the reference manual for documentation.
- It is now possible to omit type annotations when packing and unpacking
  first-class modules. The type-checker attempts to infer it from the context.
  Using the -principal option guarantees forward compatibility.
- New (module M) and (module M : S) syntax in patterns, for immediate
  unpacking of a first-class module.

Compilers:
- Revised simplification of let-alias (PR#5205, PR#5288)
- Better reporting of compiler version mismatch in .cmi files
* Warning 28 is now enabled by default.
- New option -absname to use absolute paths in error messages
- Optimize away compile-time beta-redexes, e.g. (fun x y -> e) a b.
- Added option -bin-annot to dump the AST with type annotations.
- Added lots of new warnings about unused variables, opens, fields,
  constructors, etc.
* New meaning for warning 7: it is now triggered when a method is overridden
  with the "method" keyword.  Use "method!" to avoid the warning.

Native-code compiler:
- Optimized handling of partially-applied functions (PR#5287)
- Small improvements in code generated for array bounds checks (PR#5345,
  PR#5360).
* New ARM backend (PR#5433):
    . Supports both Linux/EABI (armel) and Linux/EABI+VFPv3 (armhf).
    . Added support for the Thumb-2 instruction set with average code size
      savings of 28%.
    . Added support for position-independent code, natdynlink, profiling and
      exception backtraces.
- Generation of CFI information, and filename/line number debugging (with -g)
  annotations, enabling in particular precise stack backtraces with
  the gdb debugger. Currently supported for x86 32-bits and 64-bits only.
  (PR#5487)
- New tool: ocamloptp, the equivalent of ocamlcp for the native-code compiler.

OCamldoc:
- PR#5645: ocamldoc doesn't handle module/type substitution in signatures
- PR#5544: improve HTML output (less formatting in html code)
- PR#5522: allow refering to record fields and variant constructors
- fix PR#5419 (error message in french)
- fix PR#5535 (no cross ref to class after dump+load)
* Use first class modules for custom generators, to be able to
  load various plugins incrementally adding features to the current
  generator
* PR#5507: Use Location.t structures for locations.
- fix: do not keep code when not told to keep code.

Standard library:
- Added float functions "hypot" and "copysign" (PR#3806, PR#4752, PR#5246)
* Arg: options with empty doc strings are no longer included in the usage string
  (PR#5437)
- Array: faster implementations of "blit", "copy", "sub", "append" and "concat"
  (PR#2395, PR#2787, PR#4591)
* Hashtbl:
    . Statistically-better generic hash function based on Murmur 3 (PR#5225)
    . Fixed behavior of generic hash function w.r.t. -0.0 and NaN (PR#5222)
    . Added optional "random" parameter to Hashtbl.create to randomize
      collision patterns and improve security (PR#5572, CVE-2012-0839)
    . Added "randomize" function and "R" parameter to OCAMLRUNPARAM
      to turn randomization on by default (PR#5572, CVE-2012-0839)
    . Added new functorial interface "MakeSeeded" to support randomization
      with user-provided seeded hash functions.
    . Install new header <caml/hash.h> for C code.
- Filename: on-demand (lazy) initialization of the PRNG used by "temp_file".
- Marshal: marshalling of function values (flag Marshal.Closures) now
  also works for functions that come from dynamically-loaded modules (PR#5215)
- Random:
     . More random initialization (Random.self_init()), using /dev/urandom
       when available (e.g. Linux, FreeBSD, MacOS X, Solaris)
     * Faster implementation of Random.float (changes the generated sequences)
- Scanf: new function "unescaped" (PR#3888)
- Set and Map: more efficient implementation of "filter" and "partition"
- String: new function "map" (PR#3888)

Installation procedure:
- Compiler internals are now installed in `ocamlc -where`/compiler-libs.
  The files available there include the .cmi interfaces for all compiler
  modules, plus the following libraries:
      ocamlcommon.cma/.cmxa     modules common to ocamlc, ocamlopt, ocaml
      ocamlbytecomp.cma/.cmxa   modules for ocamlc and ocaml
      ocamloptcomp.cma/.cmxa    modules specific to ocamlopt
      ocamltoplevel.cma         modules specific to ocaml
   (PR#1804, PR#4653, frequently-asked feature).
* Some .cmi for toplevel internals that used to be installed in
  `ocamlc -where` are now to be found in  `ocamlc -where`/compiler-libs.
  Add "-I +compiler-libs" where needed.
* toplevellib.cma is no longer installed because subsumed by
  ocamlcommon.cma ocamlbytecomp.cma ocamltoplevel.cma
- Added a configuration option (-with-debug-runtime) to compile and install
  a debug version of the runtime system, and a compiler option
  (-runtime-variant) to select the debug runtime.

Bug Fixes:
- PR#1643: functions of the Lazy module whose named started with 'lazy_' have
  been deprecated, and new ones without the prefix added
- PR#3571: in Bigarrays, call msync() before unmapping to commit changes
- PR#4292: various documentation problems
- PR#4511, PR#4838: local modules remove polymorphism
* PR#4549: Filename.dirname is not handling multiple / on Unix
- PR#4688: (Windows) special floating-point values aren't converted to strings
  correctly
- PR#4697: Unix.putenv leaks memory on failure
- PR#4705: camlp4 does not allow to define types with `True or `False
- PR#4746: wrong detection of stack overflows in native code under Linux
- PR#4869: rare collisions between assembly labels for code and data
- PR#4880: "assert" constructs now show up in the exception stack backtrace
- PR#4892: Array.set could raise "out of bounds" before evaluating 3rd arg
- PR#4937: camlp4 incorrectly handles optional arguments if 'option' is
  redefined
- PR#5024: camlp4r now handles underscores in irrefutable pattern matching of
  records
- PR#5064, PR#5485: try to ensure that 4K words of stack are available
  before calling into C functions, raising a Stack_overflow exception
  otherwise.  This reduces (but does not eliminate) the risk of
  segmentation faults due to stack overflow in C code
- PR#5073: wrong location for 'Unbound record field label' error
- PR#5084: sub-sub-module building fails for native code compilation
- PR#5120: fix the output function of Camlp4.Debug.formatter
- PR#5131: compilation of custom runtime with g++ generates lots of warnings
- PR#5137: caml-types-explore does not work
- PR#5159: better documentation of type Lexing.position
- PR#5171: Map.join does more comparisons than needed
- PR#5176: emacs mode: stack overflow in regexp matcher
- PR#5179: port OCaml to mingw-w64
- PR#5211: updated Genlex documentation to state that camlp4 is mandatory for
  'parser' keyword and associated notation
- PR#5214: ocamlfind plugin invokes 'cut' utility
- PR#5218: use $(MAKE) instead of "make" in Makefiles
- PR#5224: confusing error message in non-regular type definition
- PR#5231: camlp4: fix parsing of <:str_item< type t = $x$ >>
- PR#5233: finaliser on weak array gives dangling pointers (crash)
- PR#5238, PR#5277: Sys_error when getting error location
- PR#5261, PR#5497: Ocaml source-code examples are not "copy-paste-able"
* PR#5279: executable name is not initialized properly in caml_startup_code
- PR#5290: added hash functions for channels, nats, mutexes, conditions
- PR#5295: OS threads: problem with caml_c_thread_unregister()
- PR#5301: camlp4r and exception equal to another one with parameters
- PR#5305: prevent ocamlbuild from complaining about links to _build/
- PR#5306: comparing to Thread.self() raises exception at runtime
- PR#5309: Queue.add is not thread/signal safe
- PR#5310: Ratio.create_ratio/create_normalized_ratio have misleading names
- PR#5311: better message for warning 23
* PR#5312: command-line arguments @reponsefile auto-expansion feature
  removed from the Windows OCaml runtime, to avoid conflicts with "-w @..."
- PR#5313: ocamlopt -g misses optimizations
- PR#5316: objinfo now shows ccopts/ccobjs/force_link when applicable
- PR#5318: segfault on stack overflow when reading marshaled data
- PR#5319: %r11 clobbered by Lswitch in Windows AMD64 native-code compilation
- PR#5322: type abbreviations expanding to a universal type variable
- PR#5325: (Windows) blocked Unix.recv in one thread blocks Unix.send in
  another thread
- PR#5328: under Windows, Unix.select leaves sockets in non-blocking mode
- PR#5330: thread tag with '.top' and '.inferred.mli' targets
- PR#5331: ocamlmktop is not always a shell script
- PR#5335: Unix.environment segfaults after a call to clearenv
- PR#5338: sanitize.sh has windows style end-of-lines (mingw)
- PR#5343: ocaml -rectypes is unsound wrt module subtyping
- PR#5344: some predefined exceptions need special printing
- PR#5349: Hashtbl.replace uses new key instead of reusing old key
- PR#5356: ocamlbuild handling of 'predicates' for ocamlfind
- PR#5364: wrong compilation of "((val m : SIG1) : SIG2)"
- PR#5370: ocamldep omits filename in syntax error message
- PR#5374: camlp4 creates wrong location for type definitions
- PR#5380: strange sscanf input segfault
- PR#5382: EOPNOTSUPP and ENOTSUPP different on exotic platforms
- PR#5383: build failure in Win32/MSVC
- PR#5387: camlp4: str_item and other syntactic elements with Nils are
  not very usable
- PR#5389: compaction sometimes leaves a very large heap
- PR#5393: fails to build from source on GNU/kFreeBSD because of -R link option
- PR#5394: documentation for -dtypes is missing in manpage
- PR#5397: Filename.temp_dir_name should be mutable
- PR#5410: fix printing of class application with Camlp4
- PR#5416: (Windows) Unix.(set|clear)_close_on_exec now preserves blocking mode
- PR#5435: ocamlbuild does not find .opt executables on Windows
- PR#5436: update object ids on unmarshaling
- PR#5442: camlp4: quotation issue with strings
- PR#5453: configure doesn't find X11 under Ubuntu/MultiarchSpec
- PR#5461: Double linking of bytecode modules
- PR#5463: Bigarray.*.map_file fail if empty array is requested
- PR#5465: increase stack size of ocamlopt.opt for windows
- PR#5469: private record type generated by functor loses abbreviation
- PR#5475: Wrapper script for interpreted LablTk wrongly handles command line
  parameters
- PR#5476: bug in native code compilation of let rec on float arrays
- PR#5477: use pkg-config to configure graphics on linux
- PR#5481: update camlp4 magic numbers
- PR#5482: remove bashism in test suite scripts
- PR#5495: camlp4o dies on infix definition (or)
- PR#5498: Unification with an empty object only checks the absence of
  the first method
- PR#5503: error when ocamlbuild is passed an absolute path as build directory
- PR#5509: misclassification of statically-allocated empty array that
  falls exactly at beginning of an otherwise unused data page.
- PR#5510: ocamldep has duplicate -ml{,i}-synonym options
- PR#5511: in Bigarray.reshape, unwarranted limitation on new array dimensions.
- PR#5513: Int64.div causes floating point exception (ocamlopt, x86)
- PR#5516: in Bigarray C stubs, use C99 flexible array types if possible
- PR#5518: segfault with lazy empty array
- PR#5531: Allow ocamlbuild to add ocamldoc flags through -docflag
  and -docflags switches
- PR#5543: in Bigarray.map_file, try to avoid using lseek() when growing file
- PR#5538: combining -i and -annot in ocamlc
- PR#5648: (probably fixed) test failures in tests/lib-threads
- PR#5551: repeated calls to find_in_path degrade performance
- PR#5552: Mac OS X: unrecognized gcc option "-no-cpp-precomp"
- PR#5555: add Hashtbl.reset to resize the bucket table to its initial size
- PR#5560: incompatible type for tuple pattern with -principal
- PR#5575: Random states are not marshallable across architectures
- PR#5579: camlp4: when a plugin is loaded in the toplevel,
  Token.Filter.define_filter has no effect before the first syntax error
- PR#5585: typo: "explicitely"
- PR#5587: documentation: "allows to" is not correct English
- PR#5593: remove C file when -output-obj fails
- PR#5597: register names for instrtrace primitives in embedded bytecode
- PR#5598: add backslash-space support in strings in ocamllex
- PR#5603: wrong .file debug info generated by ocamlopt -g
- PR#5604: fix permissions of files created by ocamlbuild itself
- PR#5610: new unmarshaler (from PR#5318) fails to freshen object identifiers
- PR#5614: add missing -linkall flag when compiling ocamldoc.opt
- PR#5616: move ocamlbuild documentation to the reference manual
- PR#5619: Uncaught CType.Unify exception in the compiler
- PR#5620: invalid printing of type manifest (camlp4 revised syntax)
- PR#5637: invalid printing of anonymous type parameters (camlp4 revised syntax)
- PR#5643: issues with .cfi and .loc directives generated by ocamlopt -g
- PR#5644: Stream.count broken when used with Sapp or Slazy nodes
- PR#5647: Cannot use install_printer in debugger
- PR#5651: printer for abstract data type (camlp4 revised syntax)
- PR#5654: self pattern variable location tweak
- PR#5655: ocamlbuild doesn't pass cflags when building C stubs
- PR#5657: wrong error location for abbreviated record fields
- PR#5659: ocamlmklib -L option breaks with MSVC
- PR#5661: fixes for the test suite
- PR#5668: Camlp4 produces invalid syntax for "let _ = ..."
- PR#5671: initialization of compare_ext field in caml_final_custom_operations()
- PR#5677: do not use "value" as identifier (genprintval.ml)
- PR#5687: dynlink broken when used from "output-obj" main program (bytecode)
- problem with printing of string literals in camlp4 (reported on caml-list)
- emacs mode: colorization of comments and strings now works correctly
- problem with forall and method (reported on caml-list on 2011-07-26)
- crash when using OCAMLRUNPARAM=a=X with invalid X (reported in private)

Feature wishes:
- PR#352: new option "-stdin" to make ocaml read stdin as a script
- PR#1164: better error message when mixing -a and .cmxa
- PR#1284: documentation: remove restriction on mixed streams
- PR#1496: allow configuring LIBDIR, BINDIR, and MANDIR relative to $(PREFIX)
- PR#1835: add Digest.from_hex
- PR#1898: toplevel: add option to suppress continuation prompts
- PR#4278: configure: option to disable "graph" library
- PR#4444: new String.trim function, removing leading and trailing whistespace
- PR#4549: make Filename.dirname/basename POSIX compliant
- PR#4830: add option -v to expunge.ml
- PR#4898: new Sys.big_endian boolean for machine endianness
- PR#4963, PR#5467: no extern "C" into ocaml C-stub headers
- PR#5199: tests are run only for bytecode if either native support is missing,
  or a non-empty value is set to "BYTECODE_ONLY" Makefile variable
- PR#5215: marshalling of dynlinked closure
- PR#5236: new '%revapply' primitive with the semantics 'revapply x f = f x',
    and '%apply' with semantics 'apply f x = f x'.
- PR#5255: natdynlink detection on powerpc, hurd, sparc
- PR#5295: OS threads: problem with caml_c_thread_unregister()
- PR#5297: compiler now checks existence of builtin primitives
- PR#5329: (Windows) more efficient Unix.select if all fd's are sockets
- PR#5357: warning for useless open statements
- PR#5358: first class modules don't allow "with type" declarations for types
  in sub-modules
- PR#5385: configure: emit a warning when MACOSX_DEPLOYMENT_TARGET is set
- PR#5396: ocamldep: add options -sort, -all, and -one-line
- PR#5397: Filename.temp_dir_name should be mutable
- PR#5403: give better error message when emacs is not found in PATH
- PR#5411: new directive for the toplevel: #load_rec
- PR#5420: Unix.openfile share mode (Windows)
- PR#5421: Unix: do not leak fds in various open_proc* functions
- PR#5434: implement Unix.times in win32unix (partially)
- PR#5438: new warnings for unused declarations
- PR#5439: upgrade config.guess and config.sub
- PR#5445 and others: better printing of types with user-provided names
- PR#5454: Digest.compare is missing and md5 doc update
- PR#5455: .emacs instructions, add lines to recognize ocaml scripts
- PR#5456: pa_macro: replace __LOCATION__ after macro expansion; add LOCATION_OF
- PR#5461: bytecode: emit warning when linking two modules with the same name
- PR#5478: ocamlopt assumes ar command exists
- PR#5479: Num.num_of_string may raise an exception, not reflected in the
  documentation.
- PR#5501: increase IO_BUFFER_SIZE to 64KiB
- PR#5532: improve error message when bytecode file is wrong
- PR#5555: add function Hashtbl.reset to resize the bucket table to
  its initial size.
- PR#5586: increase UNIX_BUFFER_SIZE to 64KiB
- PR#5597: register names for instrtrace primitives in embedded bytecode
- PR#5599: Add warn() tag in ocamlbuild to control -w compiler switch
- PR#5628: add #remove_directory and Topdirs.remove_directory to remove
  a directory from the load path
- PR#5636: in system threads library, issue with linking of pthread_atfork
- PR#5666: C includes don't provide a revision number
- ocamldebug: ability to inspect values that contain code pointers
- ocamldebug: new 'environment' directive to set environment variables
  for debuggee
- configure: add -no-camlp4 option

Shedding weight:
* Removed the obsolete native-code generators for Alpha, HPPA, IA64 and MIPS.
* The "DBM" library (interface with Unix DBM key-value stores) is no
  longer part of this distribution.  It now lives its own life at
  https://forge.ocamlcore.org/projects/camldbm/
* The "OCamlWin" toplevel user interface for MS Windows is no longer
  part of this distribution.  It now lives its own life at
  https://forge.ocamlcore.org/projects/ocamltopwin/

Other changes:
- Copy VERSION file to library directory when installing.