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OCaml 4.07.0

This page describes OCaml version 4.07.0, released on 2018-07-10.

Opam Switches

This release is available as multiple OPAM switches:

  • 4.07.0 — Official 4.07.0 release
  • 4.07.0+afl — Official 4.07.0 release with afl-fuzz instrumentation
  • 4.07.0+default-unsafe-string — Official 4.07.0 release without safe strings by default
  • 4.07.0+flambda — Official 4.07.0 release with flambda activated
  • 4.07.0+force-safe-string — Official 4.07.0 release with -safe-string enabled.
  • 4.07.0+fp — Official 4.07.0 release with frame-pointers
  • 4.07.0+fp+flambda — Official 4.07.0 release with frame-pointers and flambda activated

What's new

Some of the highlights in release 4.07 are:

  • The standard library is now packed into a module called Stdlib, which is open by default. This makes it easier to add new modules to the standard library without clashing with user-defined modules.

  • The Bigarray module is now part of the standard library.

  • The modules Seq, Float were added to the standard library.

  • Improvements to several error and warning messages printed by the compiler make them much easier to understand.

  • Many improvements to flambda.

  • Removed the dependency on curses/terminfo/termcap.

  • The SpaceTime profiler now works under Windows.

For a comprehensive list of changes and details on all new features, bug fixes, optimizations, etc., please consult the changelog.

Source distribution

  • Source tarball (.tar.gz) for compilation under Unix (including Linux and MacOS X) and Microsoft Windows (including Cygwin).
  • Also available in .zip format.
  • OPAM is a source-based distribution of OCaml and many companion libraries and tools. Compilation and installation are automated by powerful package managers.
  • The official development repo is hosted on GitHub.

The INSTALL file of the distribution provides detailed compilation and installation instructions -- see also the Windows release notes for instructions on how to build under Windows.

Alternative Compilers

Additionally, the following projects allow you to compile OCaml code to targets traditionally associated with other languages:

  • Js_of_ocaml is a stable OCaml to JavaScript compiler.
  • BuckleScript is a newer OCaml to JavaScript compiler. See its wiki for an explanation of how it differs from js_of_ocaml.
  • OCaml-java is a stable OCaml to Java compiler.

User's manual

The user's manual for OCaml can be:


This is the changelog.

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

Language features:

  • MPR#6023, GPR#1648: Allow type-based selection of GADT constructors (Thomas Refis and Leo White, review by Jacques Garrigue and Gabriel Scherer)

  • GPR#1546: Allow empty variants (Runhang Li, review by Gabriel Radanne and Jacques Garrigue)

Standard library:

  • MPR#4170, GPR#1674: add the constant Float.pi. (Christophe Troestler, review by Damien Doligez)

  • MPR#6139, GPR#1685: Move the Bigarray module to the standard library. Keep the bigarray library as on overlay adding the deprecated map_file functions (Jérémie Dimino, review by Mark Shinwell)

  • MPR#7690, GPR#1528: fix the float_of_string function for hexadecimal floats with very large values of the exponent. (Olivier Andrieu)

  • GPR#1002: add a new Seq module defining a list-of-thunks style iterator. Also add {to,of}_seq to several standard modules. (Simon Cruanes, review by Alain Frisch and François Bobot)

  • GPR#1010: pack all standard library modules into a single module Stdlib which is the default opened module (Stdlib itself includes Pervasives) to free up the global namespace for other standard libraries, while still allowing any OCaml standard library module to be referred to as Stdlib.Module). This is implemented efficiently using module aliases (prefixing all modules with Stdlib__, e.g. Stdlib__string). (Jérémie Dimino, David Allsopp and Florian Angeletti, review by David Allsopp and Gabriel Radanne)
  • GPR#1637: String.escaped is faster and does not allocate when called with a string that does not contain any characters needing to be escaped. (Alain Frisch, review by Xavier Leroy and Gabriel Scherer)

  • GPR#1638: add a Float module. (Nicolás Ojeda Bär, review by Alain Frisch and Jeremy Yallop)

  • GPR#1697: Tune List.init tailrec threshold so that it does not stack overflow when compiled with the Js_of_ocaml backend. (Hugo Heuzard, reviewed by Gabriel Scherer)

Other libraries:

  • MPR#7745, GPR#1629: Graphics.open_graph displays the correct window title on Windows again (fault introduced by 4.06 Unicode changes). (David Allsopp)
  • GPR#1406: Unix.isatty now returns true in the native Windows ports when passed a file descriptor connected to a Cygwin PTY. In particular, compiler colors for the native Windows ports now work under Cygwin/MSYS2. (Nicolás Ojeda Bär, review by Gabriel Scherer, David Allsopp, Xavier Leroy)
  • GPR#1451: getpwuid, getgrgid, getpwnam, getgrnam now raise Unix.error instead of returning Not_found when interrupted by a signal. (Arseniy Alekseyev, review by Mark Shinwell and Xavier Leroy)

  • GPR#1477: raw_spacetime_lib can now be used in bytecode. (Nicolás Ojeda Bär, review by Mark Shinwell)

  • GPR#1533: (a) The implementation of Thread.yield for system thread now uses nanosleep(1) for enabling better preemption. (b) Thread.delay is now an alias for Unix.sleepf. (Jacques-Henri Jourdan, review by Xavier Leroy and David Allsopp)

Compiler user-interface and warnings:

  • MPR#7663, GPR#1694: print the whole cycle and add a reference to the manual in the unsafe recursive module evaluation error message. (Florian Angeletti, report by Matej Košík, review by Gabriel Scherer)

  • GPR#1166: In OCAMLPARAM, an alternative separator can be specified as first character (instead of comma) in the set ":|; ," (Fabrice Le Fessant)

  • GPR#1358: Fix usage warnings with no mli file (Leo White, review by Alain Frisch)

  • GPR#1428: give a non dummy location for warning 49 (no cmi found) (Valentin Gatien-Baron)

  • GPR#1491: Improve error reporting for ill-typed applicative functor types, F(M).t. (Valentin Gatien-Baron, review by Florian Angeletti and Gabriel Radanne)

  • GPR#1496: Refactor the code printing explanation for unification type errors, in order to avoid duplicating pattern matches (Armaël Guéneau, review by Florian Angeletti and Gabriel Scherer)

  • GPR#1505: Add specific error messages for unification errors involving functions of type unit -> _ (Arthur Charguéraud and Armaël Guéneau, with help from Leo White, review by Florian Angeletti and Gabriel Radanne)

  • GPR#1510: Add specific explanation for unification errors caused by type constraints propagated by keywords (such as if, while, for...) (Armaël Guéneau and Gabriel Scherer, original design by Arthur Charguéraud, review by Frédéric Bour, Gabriel Radanne and Alain Frisch)

  • GPR#1515: honor the BUILD_PATH_PREFIX_MAP environment variable to enable reproducible builds (Gabriel Scherer, with help from Ximin Luo, review by Damien Doligez)

  • GPR#1534: Extend the warning printed when (*) is used, adding a hint to suggest using ( * ) instead (Armaël Guéneau, with help and review from Florian Angeletti and Gabriel Scherer)

  • GPR#1552, GPR#1577: do not warn about ambiguous variables in guards (warning 57) when the ambiguous values have been filtered by a previous clause (Gabriel Scherer and Thomas Refis, review by Luc Maranget)

  • GPR#1554: warnings 52 and 57: fix reference to manual detailed explanation (Florian Angeletti, review by Thomas Refis and Gabriel Scherer)

  • GPR#1618: add the -dno-unique-ids and -dunique-ids compiler flags (Sébastien Hinderer, review by Leo White and Damien Doligez)

  • GPR#1649 change compilation order of toplevel definitions, so that some warnings emitted by the bytecode compiler appear more in-order than before. (Luc Maranget, advice and review by Damien Doligez)

  • GPR#1806: add linscan to OCAMLPARAM options (Raja Boujbel)

Code generation and optimizations:

  • MPR#7630, GPR#1401: Faster compilation of large modules with Flambda. (Pierre Chambart, report by Emilio Jesús Gallego Arias, Pierre-Marie Pédrot and Paul Steckler, review by Gabriel Scherer and Leo White)

  • MPR#7630, GPR#1455: Disable CSE for the initialization function (Pierre Chambart, report by Emilio Jesús Gallego Arias, review by Gabriel Scherer and Xavier Leroy)

  • GPR#1370: Fix code duplication in Cmmgen (Vincent Laviron, with help from Pierre Chambart, reviews by Gabriel Scherer and Luc Maranget)

  • GPR#1486: ARM 32-bit port: add support for ARMv8 in 32-bit mode, a.k.a. AArch32. For this platform, avoid ITE conditional instruction blocks and use simpler IT blocks instead (Xavier Leroy, review by Mark Shinwell)

  • GPR#1487: Treat negated float comparisons more directly (Leo White, review by Xavier Leroy)

  • GPR#1573: emitcode: merge events after instructions reordering (Thomas Refis and Leo White, with help from David Allsopp, review by Frédéric Bour)

  • GPR#1606: Simplify the semantics of Lambda.free_variables and Lambda.subst, including some API changes in bytecomp/lambda.mli (Pierre Chambart, review by Gabriel Scherer)

  • GPR#1613: ensure that set-of-closures are processed first so that other entries in the let-rec symbol do not get dummy approximations (Leo White and Xavier Clerc, review by Pierre Chambart)

  • GPR#1617: Make string/bytes distinguishable in the bytecode. (Hugo Heuzard, reviewed by Nicolás Ojeda Bär)
  • GPR#1627: Reduce cmx sizes by sharing variable names (Flambda only) (Fuyong Quah, Leo White, review by Xavier Clerc)

  • GPR#1665: reduce the size of cmx files in classic mode by dropping the bodies of functions that will not be inlined (Fuyong Quah, review by Leo White and Pierre Chambart)

  • GPR#1666: reduce the size of cmx files in classic mode by dropping the bodies of functions that cannot be reached from the module block (Fuyong Quah, review by Leo White and Pierre Chambart)

  • GPR#1686: Turn off by default flambda invariants checks. (Pierre Chambart)

  • GPR#1707: Add Closure_origin.t to trace inlined functions to prevent infinite loops from repeatedly inlining copies of the same function. (Fu Yong Quah)

  • GPR#1740: make sure startup.o is always linked in when using -output-complete-obj. Previously, it was always linked in only on some platforms, making this option unusable on platforms where it wasn't (Jérémie Dimino, review by Sébastien Hinderer and Xavier Leroy)

Runtime system:

  • MPR#6411, GPR#1535: don't compile everything with -static-libgcc on mingw32, only dllbigarray.dll and libbigarray.a. Allows the use of C++ libraries which raise exceptions. (David Allsopp)

  • MPR#7100, GPR#1476: trigger a minor GC when custom blocks accumulate in minor heap (Alain Frisch, report by talex, review by Damien Doligez, Leo White, Gabriel Scherer)

  • GPR#1431: remove ocamlrun dependencies on curses/terminfo/termcap C library (Xavier Leroy, review by Daniel Bünzli)

  • GPR#1478: The Spacetime profiler now works under Windows (but it is not yet able to collect profiling information from C stubs). (Nicolás Ojeda Bär, review by Xavier Leroy, Mark Shinwell)

  • GPR#1483: fix GC freelist accounting for chunks larger than the maximum block size. (David Allsopp and Damien Doligez)

  • GPR#1526: install the debug and instrumented runtimes (lib{caml,asm}run{d,i}.a) (Gabriel Scherer, reminded by Julia Lawall)

  • GPR#1563: simplify implementation of LSRINT and ASRINT (Max Mouratov, review by Frédéric Bour)

  • GPR#1644: remove caml_alloc_float_array from the bytecode primitives list (it's a native code primitive) (David Allsopp)

  • GPR#1701: fix missing root bug in GPR#1476 (Mark Shinwell)

  • GPR#1752: do not alias function arguments to sigprocmask (Anil Madhavapeddy)

  • GPR#1753: avoid potential off-by-one overflow in debugger socket path length (Anil Madhavapeddy)


  • MPR#7643, GPR#1377: ocamldep, fix an exponential blowup in presence of nested structures and signatures (e.g. include struct … include(struct … end) … end) (Florian Angeletti, review by Gabriel Scherer, report by Christophe Raffalli)

  • MPR#7687, GPR#1653: deprecate -thread option, which is equivalent to -I +threads. (Nicolás Ojeda Bär, report by Daniel Bünzli)

  • MPR#7710: ocamldep -sort should exit with nonzero code in case of cyclic dependencies (Xavier Leroy, report by Mantis user baileyparker)

  • GPR#1537: boot/ocamldep is no longer included in the source distribution; boot/ocamlc -depend can be used in its place. (Nicolás Ojeda Bär, review by Xavier Leroy and Damien Doligez)

  • GPR#1585: optimize output of ocamllex -ml (Alain Frisch, review by Frédéric Bour and Gabriel Scherer)

  • GPR#1667: add command-line options -no-propt, -no-version, -no-time, -no-breakpoint and -topdirs-path to ocamldebug (Sébastien Hinderer, review by Damien Doligez)

  • GPR#1695: add the -null-crc command-line option to ocamlobjinfo. (Sébastien Hinderer, review by David Allsopp and Gabriel Scherer)

  • GPR#1710: ocamldoc, improve the 'man' rendering of subscripts and superscripts. (Gabriel Scherer)

  • GPR#1771: ocamdebug, avoid out of bound access (Thomas Refis)

Manual and documentation:

  • MPR#7613: minor reword of the "refutation cases" paragraph (Florian Angeletti, review by Jacques Garrigue)

  • PR#7647, GPR#1384: emphasize website and forum in README (Yawar Amin, review by Gabriel Scherer)

  • PR#7698, GPR#1545: improve wording in OCaml manual in several places, mostly in Chapter 1. This addresses the easier changes suggested in the PR. (Jim Fehrle, review by Florian Angeletti and David Allsopp)

  • GPR#1540: manual, decouple verbatim and toplevel style in code examples (Florian Angeletti, review by Gabriel Scherer)

  • GPR#1556: manual, add a consistency test for manual references inside the compiler source code. (Florian Angeletti, review by Gabriel Scherer)

  • GPR#1647: manual, subsection on record and variant disambiguation (Florian Angeletti, review by Alain Frisch and Gabriel Scherer)

  • GPR#1702: manual, add a signature mode for code examples (Florian Angeletti, review by Gabriel Scherer)

  • GPR#1741: manual, improve typesetting and legibility in HTML output (steinuil, review by Gabriel Scherer)

  • GPR#1757: style the html manual, changing type and layout (Charles Chamberlain, review by Florian Angeletti, Xavier Leroy, Gabriel Radanne, Perry E. Metzger, and Gabriel Scherer)

  • GPR#1765: manual, ellipsis in code examples (Florian Angeletti, review and suggestion by Gabriel Scherer)

  • GPR#1767: change html manual to use relative font sizes (Charles Chamberlain, review by Daniel Bünzli, Perry E. Metzger, Josh Berdine, and Gabriel Scherer)

  • GPR#1779: integrate the Bigarray documentation into the main manual. (Perry E. Metzger, review by Florian Angeletti and Xavier Clerc)

Type system:

  • MPR#7611, GPR#1491: reject the use of generative functors as applicative (Valentin Gatien-Baron)

  • MPR#7706, GPR#1565: in recursive value declarations, track static size of locally-defined variables (Gabriel Scherer, review by Jeremy Yallop and Leo White, report by Leo White)

  • MPR#7717, GPR#1593: in recursive value declarations, don't treat unboxed constructor size as statically known (Jeremy Yallop, report by Pierre Chambart, review by Gabriel Scherer)

  • MPR#7767, GPR#1712: restore legacy treatment of partially-applied labeled functions in let rec bindings. (Jeremy Yallop, report by Ivan Gotovchits, review by Gabriel Scherer)

  • MPR#7787, GPR#1652, GPR#1743: Don't remove module aliases in module type of and with module. The old behaviour can be obtained using the [@remove_aliases] attribute. (Leo White and Thomas Refis, review by Jacques Garrigue)
  • GPR#1468: Do not enrich type_decls with incoherent manifests (Thomas Refis and Leo White, review by Jacques Garrigue)

  • GPR#1469: Use the information from [@@immediate] annotations when computing whether a type can be [@@unboxed] (Damien Doligez, report by Stephan Muenzel, review by Alain Frisch)

  • GPR#1513: Allow compilation units to shadow sub-modules of Pervasives. For instance users can now use a file in their project. (Jérémie Dimino, review by Nicolas Ojeda Bar, Alain Frisch and Gabriel Radanne)

  • GPR#1516: Allow float array construction in recursive bindings when configured with -no-flat-float-array (Jeremy Yallop, report by Gabriel Scherer)

  • GPR#1583: propagate refined ty_arg to Parmatch checks (Thomas Refis, review by Jacques Garrigue)

  • GPR#1609: Changes to ambivalence scope tracking (Thomas Refis and Leo White, review by Jacques Garrigue)

  • GPR#1628: Treat reraise and raise_notrace as nonexpansive. (Leo White, review by Alain Frisch)

  • GPR#1778: Fix Soundness bug with non-generalized type variable and local modules. This is the same bug as MPR#7414, but using local modules instead of non-local ones. (Leo White, review by Jacques Garrigue)

Compiler distribution build system

  • MPR#5219, GPR#1680, GPR#1877: use install instead of cp in install scripts. (Gabriel Scherer, review by Sébastien Hinderer and Valentin Gatien-Baron)

  • MPR#7679: make sure .a files are erased before calling ar rc, otherwise leftover .a files from an earlier compilation may contain unwanted modules (Xavier Leroy)

  • GPR#1571: do not perform architecture tests on 32-bit platforms, allowing 64-bit back-ends to use 64-bit specific constructs (Xavier Clerc, review by Damien Doligez)

Internal/compiler-libs changes:

  • MPR#7738, GPR#1624: Asmlink.reset also resets lib_ccobjs/ccopts (Cedric Cellier, review by Gabriel Scherer)

  • GPR#1488, GPR#1560: Refreshing parmatch (Gabriel Scherer and Thomas Refis, review by Luc Maranget)

  • GPR#1502: more command line options for expect tests (Florian Angeletti, review by Gabriel Scherer)

  • GPR#1511: show code at error location in expect-style tests, using new Location.show_code_at_location function (Gabriel Scherer and Armaël Guéneau, review by Valentin Gatien-Baron and Damien Doligez)

  • GPR#1519, GPR#1532, GRP#1570: migrate tests to ocamltest (Sébastien Hinderer, review by Gabriel Scherer, Valentin Gatien-Baron and Nicolás Ojeda Bär)

  • GPR#1520: more robust implementation of Misc.no_overflow_mul (Max Mouratov, review by Xavier Leroy)

  • GPR#1557: Organise and simplify translation of primitives (Leo White, review by François Bobot and Nicolás Ojeda Bär)

  • GPR#1567: register all idents relevant for reraise (Thomas Refis, review by Alain Frisch and Frédéric Bour)

  • GPR#1586: testsuite: make promote for ocamltest tests (The new -promote option for ocamltest is experimental and subject to change/removal). (Gabriel Scherer)

  • GPR#1619: expect_test: print all the exceptions, even the unexpected ones (Thomas Refis, review by Jérémie Dimino)

  • GPR#1621: expect_test: make sure to not use the installed stdlib (Jérémie Dimino, review by Thomas Refis)

  • GPR#1646: add ocamldoc test to ocamltest and migrate ocamldoc tests to ocamltest (Florian Angeletti, review by Sébastien Hinderer)

  • GPR#1663: refactor flambda specialise/inlining handling (Leo White and Xavier Clerc, review by Pierre Chambart)

  • GPR#1679: remove Pbittest from primitives in lambda (Hugo Heuzard, review by Mark Shinwell)

  • GPR#1704: Make Ident.t abstract and immutable. (Gabriel Radanne, review by Mark Shinwell)

Bug fixes

  • MPR#4499, GPR#1479: Use native Windows API to implement Sys.getenv, Unix.getenv and Unix.environment under Windows. (Nicolás Ojeda Bär, report by Alain Frisch, review by David Allsopp, Xavier Leroy)

  • MPR#5250, GPR#1435: on Cygwin, when ocamlrun searches the path for a bytecode executable file, skip directories and other non-regular files, like other Unix variants do. (Xavier Leroy)

  • MPR#6394, GPR#1425: fix fatal_error from Parmatch.get_type_path (Virgile Prevosto, review by David Allsopp, Thomas Refis and Jacques Garrigue)

  • MPR#6604, GPR#931: Only allow directives with filename and at the beginning of the line (Tadeu Zagallo, report by Roberto Di Cosmo, review by Hongbo Zhang, David Allsopp, Gabriel Scherer, Xavier Leroy)
  • MPR#7138, MPR#7701, GPR#1693: Keep documentation comments even in empty structures and signatures (Leo White, Florian Angeletti, report by Anton Bachin)

  • MPR#7178, MPR#7253, MPR#7796, GPR#1790: Make sure a function registered with at_exit is executed only once when the program exits (Nicolás Ojeda Bär and Xavier Leroy, review by Max Mouratov)

  • MPR#7391, GPR#1620: Do not put a dummy method in object types (Thomas Refis, review by Jacques Garrigue)

  • PR#7660, GPR#1445: Use native Windows API to implement Unix.utimes in order to avoid unintended shifts of the argument timestamp depending on DST setting. (Nicolás Ojeda Bär, review by David Allsopp, Xavier Leroy)

  • MPR#7668: -principal is broken with polymorphic variants (Jacques Garrigue, report by Jun Furuse)

  • MPR#7680, GPR#1497: Incorrect interaction between Matching.for_let and Simplif.simplify_exits (Alain Frisch, report and review by Vincent Laviron)

  • MPR#7682, GPR#1495: fix [@@unboxed] for records with 1 polymorphic field (Alain Frisch, report by Stéphane Graham-Lengrand, review by Gabriel Scherer)

  • MPR#7695, GPR#1541: Fatal error: exception Ctype.Unify(_) with field override (Jacques Garrigue, report by Nicolás Ojeda Bär)

  • MPR#7704, GPR#1564: use proper variant tag in non-exhaustiveness warning (Jacques Garrigue, report by Thomas Refis)

  • MPR#7711, GPR#1581: Internal typechecker error triggered by a constraint on self type in a class type (Jacques Garrigue, report and review by Florian Angeletti)

  • MPR#7712, GPR#1576: assertion failure with type abbreviations (Thomas Refis, report by Michael O'Connor, review by Jacques Garrigue)

  • MPR#7747: Type checker can loop infinitly and consumes all computer memory (Jacques Garrigue, report by kantian)

  • MPR#7751, GPR#1657: The toplevel prints some concrete types as abstract (Jacques Garrigue, report by Matej Kosik)

  • MPR#7765, GPR#1718: When unmarshaling bigarrays, protect against integer overflows in size computations (Xavier Leroy, report by Maximilian Tschirschnitz, review by Gabriel Scherer)

  • MPR#7760, GPR#1713: Exact selection of lexing engine, that is correct "Segfault in ocamllex-generated code using 'shortest'" (Luc Maranget, Frédéric Bour, report by Stephen Dolan, review by Gabriel Scherer)

  • MPR#7769, GPR#1714: calls to Stream.junk could, under some conditions, be ignored when used on streams based on input channels. (Nicolás Ojeda Bär, report by Michael Perin, review by Gabriel Scherer)

  • MPR#7793, GPR#1766: the toplevel #use directive now accepts sequences of ;; tokens. This fixes a bug in which certain files accepted by the compiler were rejected by ocamldep. (Nicolás Ojeda Bär, report by Hugo Heuzard, review by Hugo Heuzard)

  • GPR#1517: More robust handling of type variables in mcomp (Leo White and Thomas Refis, review by Jacques Garrigue)

  • GPR#1530, GPR#1574: testsuite, fix make parallel and make one DIR=... to work on ocamltest-based tests. (Runhang Li and Sébastien Hinderer, review by Gabriel Scherer)

  • GPR#1550, GPR#1555: Make pattern matching warnings more robust to ill-typed columns (Thomas Refis, with help from Gabriel Scherer and Luc Maranget)

  • GPR#1614: consider all bound variables when inlining, fixing a compiler fatal error. (Xavier Clerc, review by Pierre Chambart, Leo White)

  • GPR#1622: fix bug in the expansion of command-line arguments under Windows which could result in some elements of Sys.argv being truncated in some cases. (Nicolás Ojeda Bär, review by Sébastien Hinderer)

  • GPR#1623: Segfault on Windows 64 bits when expanding wildcards in arguments. (Marc Lasson, review by David Allsopp, Alain Frisch, Sébastien Hinderer, Xavier Leroy, Nicolas Ojeda Bar)

  • GPR#1661: more precise principality warning regarding record fields disambiguation (Thomas Refis, review by Leo White)

  • GPR#1687: fix bug in the printing of short functor types (S1 -> S2) -> S3 (Pieter Goetschalckx, review by Gabriel Scherer)

  • GPR#1722: Scrape types in Typeopt.maybe_pointer (Leo White, review by Thomas Refis)

  • GPR#1755: ensure that a bigarray is never collected while reading complex values (Xavier Clerc, Mark Shinwell and Leo White, report by Chris Hardin, reviews by Stephen Dolan and Xavier Leroy)

  • GPR#1764: in byterun/memory.c, struct pool_block, use C99 flexible arrays if available (Xavier Leroy, review by Max Mouratov)

  • GPR#1774: ocamlopt for ARM could generate VFP loads and stores with bad offsets, rejected by the assembler. (Xavier Leroy, review by Mark Shinwell)

  • GPR#1808: handle [@inlined] attributes under a module constraint (Xavier Clerc, review by Leo White)

  • GPR#1810: use bit-pattern comparison when meeting float approximations (Xavier Clerc, report by Christophe Troestler, review by Nicolás Ojeda Bär and Gabriel Scherer)

  • GPR#1835: Fix off-by-one errors in Weak.get_copy and Weak.blit (KC Sivaramakrishnan)

  • GPR#1849: bug in runtime function generic_final_minor_update() that could lead to crashes when Gc.finalise_last is used (report and fix by Yuriy Vostrikov, review by François Bobot)