also upstream changelog):
Language features:
- Attributes and extension nodes
- Generative functors
- Module aliases
* Alternative syntax for string literals {id|...|id} (can break comments)
- Separation between read-only strings (type string) and read-write byte
sequences (type bytes). Activated by command-line option -safe-string.
Build system for the OCaml distribution:
- Use -bin-annot when building.
- Use GNU make instead of portable makefiles.
- Updated build instructions for 32-bit Mac OS X on Intel hardware.
Shedding weight:
* Removed Camlp4 from the distribution, now available as third-party software.
* Removed Labltk from the distribution, now available as a third-party library.
Type system:
* Keep typing of pattern cases independent in principal mode
- Allow opening a first-class module or applying a generative functor
in the body of a generative functor. Allow it also in the body of
an applicative functor if no types are created
* Module aliases are now typed in a specific way, which remembers their
identity. In particular this changes the signature inferred by
"module type of"
- Slight change in the criterion to distinguish private
abbreviations and private row types: create a private abbreviation for
closed objects and fixed polymorphic variants.
* Compare first class module types structurally rather than
nominally. Value subtyping allows module subtyping as long as the internal
representation is unchanged.
Compilers:
- More aggressive constant propagation, including float and
int32/int64/nativeint arithmetic. Constant propagation for floats
can be turned off with option -no-float-const-prop, for codes that
change FP rounding modes at run-time.
- New back-end optimization pass: common subexpression elimination (CSE).
(Reuses results of previous computations instead of recomputing them.)
- New back-end optimization pass: dead code elimination.
(Removes arithmetic and load instructions whose results are unused.)
- Optimization of sequences of string patterns
- Experimental native code generator for AArch64 (ARM 64 bits)
- Optimization of integer division and modulus by constant divisors
- Add "-open" command line flag for opening a single module before typing
* "-o" now sets module name to the output file name up to the first "."
(it also applies when "-o" is not given, i.e. the module name is then
the input file name up to the first ".")
* better sharing of structured constants
- new flag to keep locations in cmi files
- issue warning 3 when referring to a value marked with
the [@@ocaml.deprecated] attribute
- a new format implementation based on GADTs
* Constant exception constructors no longer allocate
- avoid unnecessary boxing in let
- Better compilation of optional arguments with default values
- ocamlopt -opaque option for incremental native compilation
Toplevel interactive system:
- New "#show_*" directives
Runtime system:
- New configure option "-no-naked-pointers" to improve performance by
avoiding page table tests during block darkening and the marking phase
of the major GC. In this mode, all out-of-heap pointers must point at
things that look like OCaml values: in particular they must have a valid
header. The colour of said headers should be black.
- Fixed bug in native code version of [caml_raise_with_string] that could
potentially lead to heap corruption.
- Blocks initialized by [CAMLlocal*] and [caml_alloc] are now filled with
[Val_unit] rather than zero.
- Fixed a major performance problem on large heaps (~1GB) by making heap
increments proportional to heap size by default
- Structural equality treats exception specifically
- efficient comparison/indexing of exceptions
- avoid using unsafe C library functions (strcpy, strcat, sprintf)
- An ISO C99-compliant C compiler and standard library is now assumed.
(Plus special exceptions for MSVC.) In particular, emulation code for
64-bit integer arithmetic was removed, the C compiler must support a
64-bit integer type.
Standard library:
* Add new modules Bytes and BytesLabels for mutable byte sequences.
- add List.sort_uniq and Set.of_list
- a faster version of "raise" which does not maintain the backtrace
- support "Unix.kill pid Sys.sigkill" under Windows
- speed improvement for Buffer
- efficient creation of uninitialized float arrays
- Improve documentation regarding finalisers and multithreading
- Trigger warning 3 for all values marked as deprecated in the documentation.
comments.
Updated buildlink3.mk to default to a full dependency (more pertinent in most
cases; usually the standard library needs to be installed for an ocaml
program to run)
Changes from 3.12 to 4.00.1 include:
OCaml 4.00.1:
-------------
Various bug fixes.
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 Algebraic 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
camltoplevel.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.
and various bug fixes.
jaapb