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Name	Modified	Size	InfoDownloads / Week
Parent folder
OTP-27.0.README.md	2024-08-13	105.9 kB	0
README.md	2024-05-17	7.8 kB	0
Totals: 2 Items		113.8 kB	0

Inital Release:          OTP 27.0
Git Tag:                 OTP-27.0
Date:                    2024-05-20
Trouble Report Id:       OTP-16607, OTP-18568, OTP-18577, OTP-18589,
                         OTP-18590, OTP-18594, OTP-18606, OTP-18608,
                         OTP-18609, OTP-18622, OTP-18639, OTP-18641,
                         OTP-18642, OTP-18648, OTP-18658, OTP-18665,
                         OTP-18667, OTP-18668, OTP-18671, OTP-18673,
                         OTP-18680, OTP-18682, OTP-18684, OTP-18699,
                         OTP-18703, OTP-18709, OTP-18713, OTP-18714,
                         OTP-18715, OTP-18716, OTP-18717, OTP-18727,
                         OTP-18741, OTP-18742, OTP-18743, OTP-18744,
                         OTP-18750, OTP-18756, OTP-18761, OTP-18766,
                         OTP-18774, OTP-18778, OTP-18779, OTP-18781,
                         OTP-18783, OTP-18784, OTP-18785, OTP-18786,
                         OTP-18787, OTP-18788, OTP-18789, OTP-18793,
                         OTP-18794, OTP-18795, OTP-18796, OTP-18801,
                         OTP-18804, OTP-18805, OTP-18806, OTP-18807,
                         OTP-18808, OTP-18809, OTP-18813, OTP-18816,
                         OTP-18819, OTP-18820, OTP-18825, OTP-18831,
                         OTP-18834, OTP-18835, OTP-18845, OTP-18846,
                         OTP-18847, OTP-18848, OTP-18849, OTP-18852,
                         OTP-18856, OTP-18859, OTP-18860, OTP-18865,
                         OTP-18870, OTP-18874, OTP-18875, OTP-18876,
                         OTP-18878, OTP-18879, OTP-18881, OTP-18884,
                         OTP-18887, OTP-18892, OTP-18894, OTP-18898,
                         OTP-18904, OTP-18908, OTP-18912, OTP-18913,
                         OTP-18914, OTP-18916, OTP-18918, OTP-18920,
                         OTP-18922, OTP-18923, OTP-18927, OTP-18928,
                         OTP-18929, OTP-18930, OTP-18934, OTP-18938,
                         OTP-18941, OTP-18942, OTP-18943, OTP-18944,
                         OTP-18945, OTP-18946, OTP-18947, OTP-18950,
                         OTP-18951, OTP-18954, OTP-18955, OTP-18959,
                         OTP-18961, OTP-18963, OTP-18965, OTP-18966,
                         OTP-18967, OTP-18968, OTP-18969, OTP-18972,
                         OTP-18973, OTP-18975, OTP-18976, OTP-18977,
                         OTP-18978, OTP-18980, OTP-18981, OTP-18984,
                         OTP-18987, OTP-18989, OTP-18992, OTP-18993,
                         OTP-18994, OTP-18995, OTP-18998, OTP-19001,
                         OTP-19004, OTP-19005, OTP-19010, OTP-19016,
                         OTP-19017, OTP-19018, OTP-19020, OTP-19022,
                         OTP-19025, OTP-19026, OTP-19027, OTP-19029,
                         OTP-19030, OTP-19033, OTP-19042, OTP-19052,
                         OTP-19053, OTP-19054, OTP-19057, OTP-19063,
                         OTP-19073, OTP-19074, OTP-19075, OTP-19077,
                         OTP-19079, OTP-19080, OTP-19081, OTP-19082,
                         OTP-19086, OTP-19087, OTP-19088, OTP-19089,
                         OTP-19090
Seq num:                 #6724, BL-312, BL-322, ERIERL-43, ERIERL-964,
                         ERIERL-967, ERIERL-985, GH-4992, GH-6152,
                         GH-6692, GH-6979, GH-6985, GH-7266, GH-7295,
                         GH-7397, GH-7432, GH-7438, GH-7483, GH-7493,
                         GH-7494, GH-7539, GH-7617, GH-7706, GH-7718,
                         GH-7972, GH-8058, GH-8061, GH-8066, GH-8159,
                         GH-8166, GH-8244, GH-8360, GH-8364, GH-8365,
                         GH-8366, GH-8452, OTP-16448, OTP-16608,
                         OTP-16875, OTP-17734, OTP-18746, OTP-18750,
                         OTP-18835, PR-6510, PR-6639, PR-6658,
                         PR-6791, PR-6985, PR-7110, PR-7125, PR-7174,
                         PR-7183, PR-7220, PR-7232, PR-7236, PR-7243,
                         PR-7267, PR-7274, PR-7299, PR-7302, PR-7313,
                         PR-7316, PR-7348, PR-7380, PR-7383, PR-7388,
                         PR-7398, PR-7419, PR-7428, PR-7441, PR-7443,
                         PR-7447, PR-7451, PR-7465, PR-7470, PR-7474,
                         PR-7475, PR-7481, PR-7491, PR-7496, PR-7528,
                         PR-7534, PR-7535, PR-7538, PR-7556, PR-7585,
                         PR-7590, PR-7592, PR-7607, PR-7628, PR-7639,
                         PR-7649, PR-7651, PR-7675, PR-7678, PR-7684,
                         PR-7697, PR-7699, PR-7700, PR-7701, PR-7702,
                         PR-7703, PR-7711, PR-7720, PR-7726, PR-7728,
                         PR-7732, PR-7738, PR-7739, PR-7740, PR-7745,
                         PR-7779, PR-7781, PR-7782, PR-7790, PR-7809,
                         PR-7816, PR-7824, PR-7844, PR-7845, PR-7846,
                         PR-7847, PR-7856, PR-7857, PR-7869, PR-7879,
                         PR-7891, PR-7898, PR-7917, PR-7918, PR-7936,
                         PR-7942, PR-7952, PR-7957, PR-7960, PR-7963,
                         PR-7973, PR-7977, PR-7981, PR-7993, PR-8003,
                         PR-8004, PR-8006, PR-8026, PR-8029, PR-8035,
                         PR-8042, PR-8048, PR-8056, PR-8063, PR-8067,
                         PR-8069, PR-8076, PR-8086, PR-8090, PR-8091,
                         PR-8092, PR-8093, PR-8095, PR-8103, PR-8111,
                         PR-8112, PR-8155, PR-8156, PR-8164, PR-8168,
                         PR-8177, PR-8182, PR-8205, PR-8230, PR-8233,
                         PR-8241, PR-8249, PR-8250, PR-8255, PR-8256,
                         PR-8258, PR-8288, PR-8308, PR-8324, PR-8345,
                         PR-8363, PR-8375, PR-8382, PR-8389, PR-8396,
                         PR-8399
System:                  OTP
Release:                 27
Application:             asn1-5.3, common_test-1.27, compiler-8.5,
                         crypto-5.5, debugger-5.4, dialyzer-5.2,
                         diameter-2.4, edoc-1.3, eldap-1.2.13,
                         erl_interface-5.5.2, erts-15.0, et-1.7.1,
                         eunit-2.9.1, ftp-1.2.2, inets-9.2,
                         jinterface-1.14.1, kernel-10.0, megaco-4.6,
                         mnesia-4.23.2, observer-2.16, odbc-2.14.3,
                         os_mon-2.10, parsetools-2.6, public_key-1.16,
                         reltool-1.0.1, runtime_tools-2.1, sasl-4.2.2,
                         snmp-5.16, ssh-5.2, ssl-11.2, stdlib-6.0,
                         syntax_tools-3.2, tftp-1.2, tools-4.0,
                         wx-2.4.2, xmerl-2.0
Predecessor:             OTP

Check out the git tag OTP-27.0, and build a full OTP system including documentation.

HIGHLIGHTS

The ssl client can negotiate and handle certificate status request (OCSP stapling support on the client side).

Thanks to voltone for interop testing and related discussions.

Own Id: OTP-18606
Application(s): public_key, ssl
Related Id(s): OTP-16448, OTP-16875

The functions is_equal/2, map/2, and filtermap/2 have been added to the modules [sets], [ordsets], and [gb_sets].

Own Id: OTP-18622
Application(s): stdlib
Related Id(s): PR-7183, PR-7232

The compiler now emits nicer error message for function head mismatches. For example, given:

erlang a() -> ok; a(_) -> error.

Erlang/OTP 26 and earlier would emit a diagnostic similar to:

text t.erl:6:1: head mismatch % 6| a(_) -> error. % | ^

while in Erlang/OTP 27 the diagnostic is similar to:

text t.erl:6:1: head mismatch: function a with arities 0 and 1 is regarded as two distinct functions. Is the number of arguments incorrect or is the semicolon in a/0 unwanted? % 6| a(_) -> error. % | ^

Own Id: OTP-18648
Application(s): compiler, stdlib
Related Id(s): PR-7383

The compiler will now merge consecutive updates of the same record.

As an example, the body of the following function will be combined into a single tuple creation instruction:

```erlang -record(r, {a,b,c,d}).

update(Value) -> R0 = #r{}, R1 = R0#r{a=Value}, R2 = R1#r{b=2}, R2#r{c=3}. ```

Own Id: OTP-18680
Application(s): compiler
Related Id(s): ERIERL-967, PR-7491, PR-8086

As announced in OTP 26.1, 0.0 is no longer considered equivalent to -0.0 when using the term equivalence operators (=:= and =/=).

The arithmetic equality operators (== and /=) and all relative comparison operations still consider 0.0 equal to -0.0.

Own Id: OTP-18717
Application(s): otp
Related Id(s): PR-7728

*** POTENTIAL INCOMPATIBILITY ***

The erl command now supports the -S flag, which is similar to the -run flag, except that it will pass all arguments up to end of the command line to the called function. (The -run flag will not pass arguments beginning with a hyphen.) Another difference is that -S will always call a function with one argument, passing an empty list if no arguments were given.

Own Id: OTP-18744
Application(s): erts
Related Id(s): PR-7470

Triple-Quoted Strings has been implemented as per EEP 64. See String in the Reference Manual.

Example:

erlang 1> """ a b c """. "a\nb\nc"

Adjacent string literals without intervening white space is now a syntax error, to avoid possible confusion with triple-quoted strings. For example:

```erlang 1> "abc""xyz". "xyz".

1:6: adjacent string literals without intervening white space ```

Own Id: OTP-18750
Application(s): stdlib, tools
Related Id(s): PR-7313, PR-7451, OTP-18746

*** POTENTIAL INCOMPATIBILITY ***

There is a new tool [tprof], which combines the functionality of [eprof] and [cprof] under one interface and adds heap profiling. It also has functionality to help with profiling process hierarchies.

Example:

```erlang 1> tprof:profile(lists, seq, [1, 16], #{type => call_memory}).

** Process <0.92.0> -- 100.00% of total *** FUNCTION CALLS WORDS PER CALL [ %] lists:seq_loop/3 5 32 6.40 [100.00] 32 [ 100.0] ok ```

Own Id: OTP-18756
Application(s): tools
Related Id(s): PR-6639

Several new functions that accept funs have been added to module [timer].

Functions apply_after/2, apply_interval/2, and apply_repeatedly/2 accept a nullary fun as the second argument, while functions apply_after/3, apply_interval/3, and apply_repeatedly/3 accept an n-ary fun as the second and a list of n arguments for the fun as the third argument.

Own Id: OTP-18808
Application(s): stdlib
Related Id(s): PR-7649

Sigils on string literals have been implemented as per EEP 66, that is: binary and string sigils in verbatim and escape characters variants, as well as a default (vanilla) Sigil. All for ordinary strings and for triple-quoted strings (EEP 64). See Sigils in the Reference Manual.

Examples:

erlang 1> ~"Björn". <<"Björn"/utf8>> 2> ~b"Björn". <<"Björn"/utf8>> 3> ~S"\s*(\w+)". "\\s*(\\w+)" 4> ~B"\s*(\w+)". <<"\\s*(\\w+)">>

Own Id: OTP-18825
Application(s): stdlib
Related Id(s): PR-7684, OTP-18750

Native coverage support has been implemented in the JIT. It will automatically be used by the [cover] tool to reduce the execution overhead when running cover-compiled code.

There are also new APIs to support native coverage without using the cover tool.

To instrument code for native coverage it must be compiled with the [line_coverage] option.

To enable native coverage in the runtime system, start it like so:

text $ erl +JPcover true

There are also the following new functions for supporting native coverage:

code:coverage_support/0
code:get_coverage/2
code:reset_coverage/1
code:get_coverage_mode/0
code:get_coverage_mode/1
code:set_coverage_mode/1

Own Id: OTP-18856
Application(s): compiler, erts, kernel, tools
Related Id(s): PR-7856

EEP-59 - Documentation Attributes has been implemented.

Documentation attributes can be used to document functions, types, callbacks, and modules. The keyword -moduledoc "Documentation here". is used to document modules, while -doc "Documentation here". can be used on top of functions, types, and callbacks to document them, respectively.

Types, callbacks, and function documentation can be set to hidden either via -doc false or -doc hidden. When documentation attributes mark a type as hidden, they will not be part of the documentation.
The documentation from moduledoc and doc gets added by default to the binary beam file, following the format of EEP-48.
Using the compiler flag warn_missing_doc will raise a warning when -doc attributes are missing in exported functions, types, and callbacks.
Using the compiler flag warn_missing_spec_documented will raise a warning when spec attributes are missing in documented functions, types, and callbacks.
moduledocs and docs may refer to external files to be embedded, such as -doc {file, "README.md"}., which refers to the file README.md found in the current working directory.
The compiler warns about exported functions whose specs refer to hidden types. Thus, there will be warnings when a hidden type (meaning, the type is not part of the documentation) gets used in an exported function.

Own Id: OTP-18916
Application(s): compiler, stdlib
Related Id(s): PR-7936

New [ets] functions ets:first_lookup/1, ets:next_lookup/2, ets:prev_lookup/2 and ets:last_lookup/1. Example: ets:next_lookup/1 is equivalent to ets:next/2 followed by ets:lookup/2 with the next key. The new combined functions are more efficient and with guaranteed atomicity.

Own Id: OTP-18923
Application(s): stdlib
Related Id(s): PR-6791

The maybe expression is now enabled by default.

To use maybe as an atom, it needs to be single-quoted. Alternatively, the maybe expression can be disabled by disabling the maybe_expr feature. That can be done by placing the following the line at the beginning of an Erlang source file:

erlang -feature(maybe_expr, disable).

Another way to disable the maybe_expr feature is by passing the -disable-feature option to erlc:

text erlc -disable-feature maybe_expr some_file.erl

Own Id: OTP-18944
Application(s): otp, stdlib
Related Id(s): PR-8067

The documentation has been migrated to use Markdown and ExDoc.

Own Id: OTP-18955
Application(s): asn1, common_test, compiler, crypto, debugger, dialyzer, diameter, edoc, eldap, erl_interface, erts, et, eunit, ftp, inets, jinterface, kernel, megaco, mnesia, observer, odbc, os_mon, parsetools, public_key, reltool, runtime_tools, sasl, snmp, ssh, ssl, stdlib, syntax_tools, tftp, tools, wx, xmerl
Related Id(s): PR-8026

Safe destructive update of tuples has been implemented in the compiler and runtime system. This allows the VM to update tuples in-place when it is safe to do so, thus improving performance by doing less copying but also by producing less garbage.

Example:

```erlang -record(rec, {a,b,c}).

update(#rec{a=needs_update,b=N}=R0) -> R = R0#rec{a=up_to_date}, if N < 0 -> R#rec{c=negative}; N == 0 -> R#rec{c=zero}; N > 0 -> R#rec{c=positive} end. ```

The record updates in each of the three clauses of the if can safely be done in-place, because variable R is not used again.

Own Id: OTP-18972
Application(s): compiler, erts
Related Id(s): PR-8090

There is a new module [trace] in Kernel providing the same trace functionality as erlang:trace/3 and erlang:trace_pattern/3, but with the addition of dynamic isolated trace sessions.

Own Id: OTP-18980
Application(s): erts, kernel

The jer (JSON Encoding Rules) for ASN.1 now use the new [json] module for encoding and decoding JSON. Thus, there is no longer any need for an external JSON library.

Own Id: OTP-19018
Application(s): asn1
Related Id(s): PR-8241

There is a new module [json] for encoding and decoding JSON.

Both encoding and decoding can be customized. Decoding can be done in a SAX-like fashion and handle multiple documents and streams of data.

Own Id: OTP-19020
Application(s): stdlib
Related Id(s): PR-8111

For security reasons, the CBC ciphers are now longer included in the list of default ciphers for TLS-1.2.

Own Id: OTP-19025
Application(s): ssl
Related Id(s): PR-8250

*** POTENTIAL INCOMPATIBILITY ***

POTENTIAL INCOMPATIBILITIES

The pid field returned from erlang:fun_info/1,2 is now always the pid for the init process of the local node, not the pid for the actual process that created the fun.

Own Id: OTP-18594
Application(s): erts
Related Id(s): PR-7274

By default, escripts will now be compiled instead of interpreted. That means that the compiler application must be installed.

Own Id: OTP-18639
Application(s): erts
Related Id(s): PR-7348

Introduced a default value for httpd_server name configuration to improve ease of use.

Own Id: OTP-18641
Application(s): inets
Related Id(s): PR-7316

As announced in OTP 26.1, 0.0 is no longer considered equivalent to -0.0 when using the term equivalence operators (=:= and =/=).

The arithmetic equality operators (== and /=) and all relative comparison operations still consider 0.0 equal to -0.0.

Own Id: OTP-18717
Application(s): otp
Related Id(s): PR-7728

*** HIGHLIGHT ***

Triple-Quoted Strings has been implemented as per EEP 64. See String in the Reference Manual.

Example:

erlang 1> """ a b c """. "a\nb\nc"

Adjacent string literals without intervening white space is now a syntax error, to avoid possible confusion with triple-quoted strings. For example:

```erlang 1> "abc""xyz". "xyz".

1:6: adjacent string literals without intervening white space ```

Own Id: OTP-18750
Application(s): stdlib, tools
Related Id(s): PR-7313, PR-7451, OTP-18746

*** HIGHLIGHT ***

The documentation for the preprocessor now mentions that defined(Name) can be called in the condition for an -if or -elif directive to test whether Name is the name of a defined macro. (This feature was implemented in OTP 21.)

If a function call in an -if or -elif with a name that is not the name of a guard BIF, there would not be a compilation error, but would instead cause the lines following the directive to be skipped. This has now been changed to be a compilation error.

Own Id: OTP-18784
Application(s): compiler, otp, stdlib
Related Id(s): GH-7706, PR-7726

The existing experimental support for archive files will be changed in a future release. The support for having an archive in an escript will remain, but the support for using archives in a release will either become more limited or completely removed.

As of Erlang/OTP 27, the function code:lib_dir/2, the -code_path_choice flag, and using [erl_prim_loader] for reading members of an archive are deprecated.

To remain compatible with future version of Erlang/OTP escript scripts that need to retrieve data files from its archive should use escript:extract/2 instead of erl_prim_loader and code:lib_dir/2.

Own Id: OTP-18966
Application(s): kernel, otp
Related Id(s): PR-8091

The order in which the compiler looks up options has changed.

When there is a conflict in the compiler options given in the -compile() attribute and options given to the compiler, the options given in the -compile() attribute overrides the option given to the compiler, which in turn overrides options given in the ERL_COMPILER_OPTIONS environment variable.

Example:

If some_module.erl has the following attribute:

erlang -compile([nowarn_missing_spec]).

and the compiler is invoked like so:

text % erlc +warn_missing_spec some_module.erl

no warnings will be issued for functions that do not have any specs.

Own Id: OTP-18968
Application(s): compiler
Related Id(s): GH-6979, PR-8093

The existing function ssl:key_exporter_materials/4 is now documented and supported.

Own Id: OTP-19016
Application(s): crypto, public_key
Related Id(s): PR-8233

The implementations of http_uri:encode/1 and http_uri:decode/1 are now replaced with their equivalent, but bug free versions from module [uri_string], namely uri_string:quote/1 and uri_string:unquote/1.

Own Id: OTP-19022
Application(s): inets

For security reasons, the CBC ciphers are now longer included in the list of default ciphers for TLS-1.2.

Own Id: OTP-19025
Application(s): ssl
Related Id(s): PR-8250

*** HIGHLIGHT ***

The error handling the simple_one_for_one supervisor has been enhanced. A transient child returning ignore will no longer cause a crash.

Also, automatic shutdown has been disabled because it does not make sense for this supervisor type. That is was allowed is considered a bug. Therefore, we don't consider this an incompatible change.

Own Id: OTP-19029
Application(s): stdlib
Related Id(s): PR-8230

Due to another attack on PKCS #1 v1.5 padding, known as the Marvin attack, about which we were alerted by Hubert Kario from Red Hat. You can find more details about the attack at https://people.redhat.com/~hkario/marvin/ Functions that may be vulnerable are now deprecated.

Note that you might mitigate the problem by using appropriate versions of OpenSSL together with our software, but we recommend not using them at all.

Also avoid using TLS versions prior to TLS-1.2 (not supported by default) and do not enable RSA-key exchange cipher suites (not supported by default).

Own Id: OTP-19075
Application(s): crypto, public_key

Some default values in Xmerl has been changed to avoid XML External Entity (XXE) vulnerabilities if you're parsing untrusted XML.

xmerl_scan: the default value for allow_entities has changed to false. xmerl_sax_parser: the default value for external_entities has changed to none.

Own Id: OTP-19079
Application(s): xmerl
Related Id(s): GH-7539

OTP-27.0

Fixed Bugs and Malfunctions

As announced in OTP 26.1, 0.0 is no longer considered equivalent to -0.0 when using the term equivalence operators (=:= and =/=).

The arithmetic equality operators (== and /=) and all relative comparison operations still consider 0.0 equal to -0.0.

Own Id: OTP-18717
Related Id(s): PR-7728

*** HIGHLIGHT ***

*** POTENTIAL INCOMPATIBILITY ***

The documentation for the preprocessor now mentions that defined(Name) can be called in the condition for an -if or -elif directive to test whether Name is the name of a defined macro. (This feature was implemented in OTP 21.)

Own Id: OTP-18784
Related Id(s): GH-7706, PR-7726

*** POTENTIAL INCOMPATIBILITY ***

Improvements and New Features

configure scripts of the OTP build system are now generated using Autoconf 2.72.

Own Id: OTP-18943

The maybe expression is now enabled by default.

erlang -feature(maybe_expr, disable).

Another way to disable the maybe_expr feature is by passing the -disable-feature option to erlc:

text erlc -disable-feature maybe_expr some_file.erl

Own Id: OTP-18944
Related Id(s): PR-8067

*** HIGHLIGHT ***

By default configure scripts used when building OTP will now try to enable support for timestamps that will work after mid-January 2038. This has typically only been an issue on 32-bit platforms.

If configure cannot figure out how to enable such timestamps, it will abort with an error message. If you want to build the system anyway, knowing that the system will not function properly after mid-January 2038, you can pass the --disable-year2038 option to configure, which will enable configure to continue without support for timestamps after mid-January 2038.

Own Id: OTP-18965
Related Id(s): PR-8095

The existing experimental support for archive files will be changed in a future release. The support for having an archive in an escript will remain, but the support for using archives in a release will either become more limited or completely removed.

As of Erlang/OTP 27, the function code:lib_dir/2, the -code_path_choice flag, and using [erl_prim_loader] for reading members of an archive are deprecated.

Own Id: OTP-18966
Related Id(s): PR-8091

*** POTENTIAL INCOMPATIBILITY ***

The restriction for the expression that gives a default value for a record field is now documented.

Own Id: OTP-18995
Related Id(s): GH-8166, PR-8177

asn1-5.3

Fixed Bugs and Malfunctions

Multiple bugs has been eliminated in the specialized decode feature.

Own Id: OTP-18813
Related Id(s): PR-7790

Improvements and New Features

Specs have been added to all asn1ct API functions.

Own Id: OTP-18804
Related Id(s): PR-7738

The documentation has been migrated to use Markdown and ExDoc.

Own Id: OTP-18955
Related Id(s): PR-8026

*** HIGHLIGHT ***

The jer (JSON Encoding Rules) for ASN.1 now use the new [json] module for encoding and decoding JSON. Thus, there is no longer any need for an external JSON library.

Own Id: OTP-19018
Related Id(s): PR-8241

*** HIGHLIGHT ***

Full runtime dependencies of asn1-5.3

erts-14.0, kernel-9.0, stdlib-5.0

common_test-1.27

Improvements and New Features

Calls to ct:capture_start/0 and ct:capture_stop/0 are now synchronous to ensure that all output is captured.

Own Id: OTP-18658
Related Id(s): PR-7380

The order in which multiple hooks are executed can now be reversed after each config function. See CTH Execution Order.

Own Id: OTP-18682
Related Id(s): ERIERL-43, GH-7397, PR-7496

The default CSS will now include a basic dark mode handling if it is preferred by the browser.

Own Id: OTP-18761
Related Id(s): PR-7428

-callback attributes have been added to [ct_suite] and [ct_hooks].

Own Id: OTP-18781
Related Id(s): PR-7701

The built-in cth_log_redirect hook can now be configured to replace default logger reports in terminal with HTML logs.

Own Id: OTP-18875
Related Id(s): PR-7891

Error handling for the [ct_property_test] framework has been enhanced.

Own Id: OTP-18881
Related Id(s): PR-7824

Enhance test case documentation, making it clear how a test case can be failed.

Own Id: OTP-18892
Related Id(s): PR-7869

The failing line in the test source code is now colored to make it easier to find on the screen.

Own Id: OTP-18898
Related Id(s): PR-7917

Function specifications and types have been added to all public API functions.

Own Id: OTP-18913

The documentation has been migrated to use Markdown and ExDoc.

Own Id: OTP-18955
Related Id(s): PR-8026

*** HIGHLIGHT ***

The suite execution elapsed time is now included in the index page.

Own Id: OTP-18981
Related Id(s): GH-7972, PR-8112

Full runtime dependencies of common_test-1.27

compiler-6.0, crypto-4.5, debugger-4.1, erts-7.0, ftp-1.0, inets-6.0, kernel-8.4, observer-2.1, runtime_tools-1.8.16, sasl-2.5, snmp-5.1.2, ssh-4.0, stdlib-4.0, syntax_tools-1.7, tools-3.2, xmerl-1.3.8

compiler-8.5

Fixed Bugs and Malfunctions

Generators for binary comprehensions could be evaluated before it was known that they would be needed. That could result in a binary comprehensions failing if a generator that should not be evaluated until later failed.

As an example, consider this module:

```erlang -module(t). -export([f/0]).

f() -> <<0 || _ <- [], _ <- ok, false>>. ```

In Erlang/OTP 26 it would fail like so:

erlang 1> t:f(). ** exception error: bad generator ok in function t:f/0 (t.erl, line 6)

In Erlang/OTP 27 it returns an empty binary:

erlang 1> t:f(). <<>>

Own Id: OTP-18703
Related Id(s): GH-7494, PR-7538

The documentation for the preprocessor now mentions that defined(Name) can be called in the condition for an -if or -elif directive to test whether Name is the name of a defined macro. (This feature was implemented in OTP 21.)

Own Id: OTP-18784
Related Id(s): GH-7706, PR-7726

*** POTENTIAL INCOMPATIBILITY ***

Improvements and New Features

The compiler now emits nicer error message for function head mismatches. For example, given:

erlang a() -> ok; a(_) -> error.

Erlang/OTP 26 and earlier would emit a diagnostic similar to:

text t.erl:6:1: head mismatch % 6| a(_) -> error. % | ^

while in Erlang/OTP 27 the diagnostic is similar to:

Own Id: OTP-18648
Related Id(s): PR-7383

*** HIGHLIGHT ***

The compiler now optimizes creation of binaries that are known to be constant.

Consider this example:

```erlang bin() -> C = char(), <<C>>.

char() -> $*. ```

Essentially, the compiler rewrites the example to the slightly more efficient:

```erlang bin() -> _ = char(), <<$*>>.

char() -> $*. ```

Own Id: OTP-18673
Related Id(s): ERIERL-964, PR-7474

The compiler will now merge consecutive updates of the same record.

As an example, the body of the following function will be combined into a single tuple creation instruction:

```erlang -record(r, {a,b,c,d}).

update(Value) -> R0 = #r{}, R1 = R0#r{a=Value}, R2 = R1#r{b=2}, R2#r{c=3}. ```

Own Id: OTP-18680
Related Id(s): ERIERL-967, PR-7491, PR-8086

*** HIGHLIGHT ***

Improved the performance of the alias analysis pass.

Own Id: OTP-18714
Related Id(s): GH-7432, PR-7528

-spec attributes are now used for documentation.

Own Id: OTP-18801
Related Id(s): PR-7739

Native coverage support has been implemented in the JIT. It will automatically be used by the [cover] tool to reduce the execution overhead when running cover-compiled code.

There are also new APIs to support native coverage without using the cover tool.

To instrument code for native coverage it must be compiled with the [line_coverage] option.

To enable native coverage in the runtime system, start it like so:

text $ erl +JPcover true

There are also the following new functions for supporting native coverage:

code:coverage_support/0
code:get_coverage/2
code:reset_coverage/1
code:get_coverage_mode/0
code:get_coverage_mode/1
code:set_coverage_mode/1

Own Id: OTP-18856
Related Id(s): PR-7856

*** HIGHLIGHT ***

EEP-59 - Documentation Attributes has been implemented.

Types, callbacks, and function documentation can be set to hidden either via -doc false or -doc hidden. When documentation attributes mark a type as hidden, they will not be part of the documentation.
The documentation from moduledoc and doc gets added by default to the binary beam file, following the format of EEP-48.
Using the compiler flag warn_missing_doc will raise a warning when -doc attributes are missing in exported functions, types, and callbacks.
Using the compiler flag warn_missing_spec_documented will raise a warning when spec attributes are missing in documented functions, types, and callbacks.
moduledocs and docs may refer to external files to be embedded, such as -doc {file, "README.md"}., which refers to the file README.md found in the current working directory.
The compiler warns about exported functions whose specs refer to hidden types. Thus, there will be warnings when a hidden type (meaning, the type is not part of the documentation) gets used in an exported function.

Own Id: OTP-18916
Related Id(s): PR-7936

*** HIGHLIGHT ***

The documentation has been migrated to use Markdown and ExDoc.

Own Id: OTP-18955
Related Id(s): PR-8026

*** HIGHLIGHT ***

The order in which the compiler looks up options has changed.

Example:

If some_module.erl has the following attribute:

erlang -compile([nowarn_missing_spec]).

and the compiler is invoked like so:

text % erlc +warn_missing_spec some_module.erl

no warnings will be issued for functions that do not have any specs.

Own Id: OTP-18968
Related Id(s): GH-6979, PR-8093

*** POTENTIAL INCOMPATIBILITY ***

Safe destructive update of tuples has been implemented in the compiler and runtime system. This allows the VM to update tuples in-place when it is safe to do so, thus improving performance by doing less copying but also by producing less garbage.

Example:

```erlang -record(rec, {a,b,c}).

update(#rec{a=needs_update,b=N}=R0) -> R = R0#rec{a=up_to_date}, if N < 0 -> R#rec{c=negative}; N == 0 -> R#rec{c=zero}; N > 0 -> R#rec{c=positive} end. ```

The record updates in each of the three clauses of the if can safely be done in-place, because variable R is not used again.

Own Id: OTP-18972
Related Id(s): PR-8090

*** HIGHLIGHT ***

Improved the match context reuse optimization slightly, allowing match contexts to be passed as-is to bit_size/1 and byte_size/1.

Own Id: OTP-18987

m:erl_lint (and by extension the [compiler]) will now warn for code using deprecated callbacks.

The only callback currenly deprecated is format_status/2 in gen_server, gen_event and gen_statem.

You can use nowarn_deprecated_callback to silence the warning.

Own Id: OTP-19010
Related Id(s): PR-8205

Full runtime dependencies of compiler-8.5

crypto-5.1, erts-13.0, kernel-8.4, stdlib-6.0

crypto-5.5

Improvements and New Features

The documentation has been migrated to use Markdown and ExDoc.

Own Id: OTP-18955
Related Id(s): PR-8026

*** HIGHLIGHT ***

Removed functions crypto_dyn_iv_init/3 and crypto_dyn_iv_update/3 which were marked as deprecated since OTP 25.

Own Id: OTP-18973

Add support for sm3 hash and hmac.

Own Id: OTP-18975
Related Id(s): PR-6658

OPENSSL_thread_stop is called when crypto is purged to not leak thread specific data.

Own Id: OTP-18978
Related Id(s): PR-7809

Add SM4 block cipher implemented according to GB/T 32907-2016.

Own Id: OTP-19005
Related Id(s): PR-8168

The existing function ssl:key_exporter_materials/4 is now documented and supported.

Own Id: OTP-19016
Related Id(s): PR-8233

*** POTENTIAL INCOMPATIBILITY ***

Due to another attack on PKCS #1 v1.5 padding, known as the Marvin attack, about which we were alerted by Hubert Kario from Red Hat. You can find more details about the attack at https://people.redhat.com/~hkario/marvin/ Functions that may be vulnerable are now deprecated.

Note that you might mitigate the problem by using appropriate versions of OpenSSL together with our software, but we recommend not using them at all.

Also avoid using TLS versions prior to TLS-1.2 (not supported by default) and do not enable RSA-key exchange cipher suites (not supported by default).

Own Id: OTP-19075
*** POTENTIAL INCOMPATIBILITY ***

Full runtime dependencies of crypto-5.5

erts-9.0, kernel-5.3, stdlib-3.9

debugger-5.4

Fixed Bugs and Malfunctions

The dependencies for this application are now listed in the app file.

Own Id: OTP-18831
Related Id(s): PR-7441

Improvements and New Features

Type specs have been added to all API functions.

Own Id: OTP-18819
Related Id(s): PR-7781

The documentation has been migrated to use Markdown and ExDoc.

Own Id: OTP-18955
Related Id(s): PR-8026

*** HIGHLIGHT ***

The Debugger now use a trace session for its internal use of tracing to avoid interfering with the user's use of tracing.

Own Id: OTP-19074
Related Id(s): PR-8389

Full runtime dependencies of debugger-5.4

compiler-8.0, erts-15.0, kernel-10.0, stdlib-3.15, wx-2.0

dialyzer-5.2

Improvements and New Features

The --gui option for Dialyzer has been removed.

Own Id: OTP-18667
Related Id(s): PR-7443

The documentation has been migrated to use Markdown and ExDoc.

Own Id: OTP-18955
Related Id(s): PR-8026

*** HIGHLIGHT ***

Full runtime dependencies of dialyzer-5.2

compiler-8.0, erts-12.0, kernel-8.0, stdlib-5.0, syntax_tools-2.0

diameter-2.4

Improvements and New Features

-callback attributes have been added to [diameter_app] and [diameter_transport].

Own Id: OTP-18783
Related Id(s): PR-7699

The documentation has been migrated to use Markdown and ExDoc.

Own Id: OTP-18955
Related Id(s): PR-8026

*** HIGHLIGHT ***

Pick peer can now also handle request of type #diameter_packet{}.

Own Id: OTP-19090
Related Id(s): PR-8399

Full runtime dependencies of diameter-2.4

erts-10.0, kernel-3.2, ssl-9.0, stdlib-5.0

edoc-1.3

Fixed Bugs and Malfunctions

EEP 48 doc chunks now properly include links within {@type } macros.

Own Id: OTP-18945
Related Id(s): PR-8063

@hidden now means hidden in EEP 48 doc chunks instead of none.

Own Id: OTP-18946
Related Id(s): PR-8063

Improvements and New Features

There is a new edoc_html_to_markdown module that can be used to convert EEP-48 application/html+erlang to Markdown.

Own Id: OTP-18947
Related Id(s): PR-8063

The documentation has been migrated to use Markdown and ExDoc.

Own Id: OTP-18955
Related Id(s): PR-8026

*** HIGHLIGHT ***

Added module [edoc_doclet_markdown] that can be used to convert EDoc style documentation to Markdown documentation attributes.

Own Id: OTP-19052
Related Id(s): PR-8308

Full runtime dependencies of edoc-1.3

erts-11.0, inets-5.10, kernel-7.0, stdlib-4.0, syntax_tools-2.0, xmerl-1.3.7

eldap-1.2.13

Improvements and New Features

The documentation has been migrated to use Markdown and ExDoc.

Own Id: OTP-18955
Related Id(s): PR-8026

*** HIGHLIGHT ***

Full runtime dependencies of eldap-1.2.13

asn1-3.0, erts-6.0, kernel-3.0, ssl-5.3.4, stdlib-3.4

erl_interface-5.5.2

Improvements and New Features

The documentation has been migrated to use Markdown and ExDoc.

Own Id: OTP-18955
Related Id(s): PR-8026

*** HIGHLIGHT ***

Known Bugs and Problems

The ei API for decoding/encoding terms is not fully 64-bit compatible since terms that have a representation on the external term format larger than 2 GB cannot be handled.

Own Id: OTP-16607
Related Id(s): OTP-16608

erts-15.0

Fixed Bugs and Malfunctions

Bugs in how erl -extra interacts with passing flags via ERL_*FLAGS or -args_file have been fixed.

Own Id: OTP-18766
Related Id(s): PR-7639

Fixed a bug that prevented the emulator from building on recent versions of Yocto Linux.

Own Id: OTP-18918
Related Id(s): PR-7952

Fixed spectre mitigation configure test to work with GCC patches to always add -fcf-protection=full.

Own Id: OTP-18928
Related Id(s): PR-8006

A call to socket:[recv|recvfrom|recvmsg]/* with Timeout = 0 on Windows could cause a (case clause) crash if data is immediately available.

Own Id: OTP-19063
Related Id(s): OTP-18835

Fix bug on Windows where exit_status would not be sent when a port exits after the stdin/stdout handles have been closed.

Own Id: OTP-19077
Related Id(s): PR-8324

Improvements and New Features

Refactored how the JIT handles POSIX signals and how they affect thread stacks, allowing us to use the native stack register for Erlang stacks on more platforms.

Notably, containers built on 64-bit x86 Alpine Linux images will now perform much better in sequential code. As an example, running dialyzer over the OTP code base finishes about 15% quicker.

Own Id: OTP-18568
Related Id(s): PR-7174

The [instrument] module can now track allocations on a per-process or per-port basis.

Own Id: OTP-18577
Related Id(s): PR-7236

The pid field returned from erlang:fun_info/1,2 is now always the pid for the init process of the local node, not the pid for the actual process that created the fun.

Own Id: OTP-18594
Related Id(s): PR-7274

*** POTENTIAL INCOMPATIBILITY ***

By default, escripts will now be compiled instead of interpreted. That means that the compiler application must be installed.

Own Id: OTP-18639
Related Id(s): PR-7348

*** POTENTIAL INCOMPATIBILITY ***

A binary returned from the [socket] receive functions is no longer created as a sub binary of an often large receive buffer binary (socket option {otp,rcvbuf}). This avoids space waste, trusting the allocators to implement reallocation efficiently.

Own Id: OTP-18642
Related Id(s): GH-6152, PR-7465

The default process limit has been raised to 1048576 processes.

Own Id: OTP-18699
Related Id(s): PR-7388

The erlang:system_monitor/2 functionality is now able to monitor long message queues in the system.

Own Id: OTP-18709
Related Id(s): PR-7651

The erl command now supports the -S flag, which is similar to the -run flag, except that it will pass all arguments up to end of the command line to the called function. (The -run flag will not pass arguments beginning with a hyphen.) Another difference is that -S will always call a function with one argument, passing an empty list if no arguments were given.

Own Id: OTP-18744
Related Id(s): PR-7470

*** HIGHLIGHT ***

When implementing an alternative carrier for the Erlang distribution, a separate input handler process may now be registered, using erlang:dist_ctrl_input_handler/2, also in the case when the distribution controller is a port.

Own Id: OTP-18774
Related Id(s): PR-7110

The call stack trace has now been added to the error reported by erlang:process_flag/2 when max_heap_size limit has been exceeded.

Own Id: OTP-18779
Related Id(s): PR-7592

-callback attributes have been added to [erl_tracer].

Own Id: OTP-18794
Related Id(s): PR-7703

For inet_backend = socket, setting the active socket option alone, to once, true or N has been optimized, as well as the corresponding data delivery.

Own Id: OTP-18835

New functions socket:sendv/* for sending I/O vectors have been added.

Own Id: OTP-18845

Socket options that take string now also accept binaries.

Own Id: OTP-18849
Related Id(s): PR-6510

Native coverage support has been implemented in the JIT. It will automatically be used by the [cover] tool to reduce the execution overhead when running cover-compiled code.

There are also new APIs to support native coverage without using the cover tool.

To instrument code for native coverage it must be compiled with the [line_coverage] option.

To enable native coverage in the runtime system, start it like so:

text $ erl +JPcover true

There are also the following new functions for supporting native coverage:

code:coverage_support/0
code:get_coverage/2
code:reset_coverage/1
code:get_coverage_mode/0
code:get_coverage_mode/1
code:set_coverage_mode/1

Own Id: OTP-18856
Related Id(s): PR-7856

*** HIGHLIGHT ***

Changed the default value of the command line flag -code_path_choice to strict.

Note that for application systems using archives, it is necessary to add the code_path_choice relaxed to the command line that invokes erl.

Own Id: OTP-18894
Related Id(s): PR-7243

Added module loading to erl -init_debug printouts.

Own Id: OTP-18929
Related Id(s): PR-8004

When the runtime system halts, it performs various flush operations before terminating. By default there is no limit on how much time the flush operations are allowed to take. A new halt flush timeout functionality has been introduced which can be used for limiting the amount of time that the flushing operations are allowed to take. For more information see the documentation of the [flush_timeout] option of the erlang:halt/2 BIF and the documentation of the erl [+zhft <Timeout>] command line flag.

Own Id: OTP-18938
Related Id(s): GH-7438, PR-8035

Optimized code loading by moving certain operations from the code server to the caller.

Own Id: OTP-18941
Related Id(s): PR-7981

Updated asmjit to version a465fe71ab3d0e224b2b4bd0fac69ae68ab9239d

Own Id: OTP-18942

The deprecated functions in [zlib] have been removed. That includes inflateChunk/{1,2}, getBufSize/1, setBufSize/2, the CRC32 functions, and the Adler checksum functions.

Own Id: OTP-18950

The documentation has been migrated to use Markdown and ExDoc.

Own Id: OTP-18955
Related Id(s): PR-8026

*** HIGHLIGHT ***

Safe destructive update of tuples has been implemented in the compiler and runtime system. This allows the VM to update tuples in-place when it is safe to do so, thus improving performance by doing less copying but also by producing less garbage.

Example:

```erlang -record(rec, {a,b,c}).

update(#rec{a=needs_update,b=N}=R0) -> R = R0#rec{a=up_to_date}, if N < 0 -> R#rec{c=negative}; N == 0 -> R#rec{c=zero}; N > 0 -> R#rec{c=positive} end. ```

The record updates in each of the three clauses of the if can safely be done in-place, because variable R is not used again.

Own Id: OTP-18972
Related Id(s): PR-8090

*** HIGHLIGHT ***

The obsolete and undocumented support for opening a port to an external resource by passing an atom (or a string) as first argument to open_port(), implemented by the vanilla driver, has been removed. This feature has been scheduled for removal in OTP 27 since the release of OTP 26.

Own Id: OTP-18976
Related Id(s): PR-7125

An optional NIF callback ERL_NIF_OPT_ON_UNLOAD_THREAD to be called by all scheduler threads when a NIF library is unloaded. Used for releasing thread specific data. Can be set with function enif_set_option.

Own Id: OTP-18977
Related Id(s): PR-7809

There is a new module [trace] in Kernel providing the same trace functionality as erlang:trace/3 and erlang:trace_pattern/3, but with the addition of dynamic isolated trace sessions.

Own Id: OTP-18980
*** HIGHLIGHT ***

Added the +MMlp on|off emulator option to let the mseg allocator use "large pages" (sometimes known as "huge pages" or "super pages"). This currently only affects super-carrier allocations, but may be extended in the future.

Own Id: OTP-18984
Related Id(s): PR-7977

inet_backend = socket has been optimized and reworked to be more compatible with the original inet_backend = inet.

Own Id: OTP-19004
Related Id(s): OTP-18835

The socket documentation has been reworked, and due to that a few details were fixed:
socket:is_supported/1 now returns true for example for protocols that is a "category", not an item.
socket:cancel_monitor/1 no longer badargs for a monitor that was set by another process, instead it returns false as for other unknown reference()s.

Own Id: OTP-19054

Full runtime dependencies of erts-15.0

kernel-9.0, sasl-3.3, stdlib-4.1

et-1.7.1

Fixed Bugs and Malfunctions

The dependencies for this application are now listed in the app file.

Own Id: OTP-18831
Related Id(s): PR-7441

Dialyzer warnings due to type specs added in [dbg] have been eliminated.

Own Id: OTP-18860

Improvements and New Features

The documentation has been migrated to use Markdown and ExDoc.

Own Id: OTP-18955
Related Id(s): PR-8026

*** HIGHLIGHT ***

Full runtime dependencies of et-1.7.1

erts-9.0, kernel-5.3, runtime_tools-1.10, stdlib-3.4, wx-1.2

eunit-2.9.1

Improvements and New Features

The documentation has been migrated to use Markdown and ExDoc.

Own Id: OTP-18955
Related Id(s): PR-8026

*** HIGHLIGHT ***

Full runtime dependencies of eunit-2.9.1

erts-9.0, kernel-5.3, stdlib-3.4

ftp-1.2.2

Fixed Bugs and Malfunctions

Dialyzer warnings due to type specs added in [dbg] have been eliminated.

Own Id: OTP-18860

Improvements and New Features

The documentation has been migrated to use Markdown and ExDoc.

Own Id: OTP-18955
Related Id(s): PR-8026

*** HIGHLIGHT ***

Full runtime dependencies of ftp-1.2.2

erts-7.0, kernel-6.0, runtime_tools-1.15.1, ssl-10.2, stdlib-3.5

inets-9.2

Improvements and New Features

Introduced a default value for httpd_server name configuration to improve ease of use.

Own Id: OTP-18641
Related Id(s): PR-7316

*** POTENTIAL INCOMPATIBILITY ***

The httpd module has been extended with an API for simple serving directory content over HTTP. With this change, the current working directory can be served like this:

text erl -S httpd

An arbitrary directory can be served like this:

text erl -S httpd serve path/to/dir

Own Id: OTP-18727
Related Id(s): PR-7299

Added -callback attributes to [httpd], [mod_esi], and [mod_security].

Own Id: OTP-18786
Related Id(s): PR-7700

Inets now uses a relative redirect with an absolute path to prevent whoever is running Inets from having to configure the ServerName to match the network-reachable host name of the server.

Own Id: OTP-18809
Related Id(s): GH-7617, PR-7678

inets processes now use proc_lib:set_label/1 to improve observeability.

Own Id: OTP-18927
Related Id(s): PR-8029

The documentation has been migrated to use Markdown and ExDoc.

Own Id: OTP-18955
Related Id(s): PR-8026

*** HIGHLIGHT ***

The implementations of http_uri:encode/1 and http_uri:decode/1 are now replaced with their equivalent, but bug free versions from module [uri_string], namely uri_string:quote/1 and uri_string:unquote/1.

Own Id: OTP-19022
*** POTENTIAL INCOMPATIBILITY ***

With this change, the API specs are updated.

Own Id: OTP-19033

Full runtime dependencies of inets-9.2

erts-14.0, kernel-9.0, mnesia-4.12, public_key-1.13, runtime_tools-1.8.14, ssl-9.0, stdlib-5.0, stdlib-6.0

jinterface-1.14.1

Improvements and New Features

The documentation has been migrated to use Markdown and ExDoc.

Own Id: OTP-18955
Related Id(s): PR-8026

*** HIGHLIGHT ***

kernel-10.0

Fixed Bugs and Malfunctions

Fixed a crash when calling file:delete/2 with an empty option list.

Own Id: OTP-18590
Related Id(s): PR-7220

New functions have been added to the undocumented module [inet_dns] that take a flag to specify if encode/decode is for mDNS. This affects how CLASS values in the private range, with the top bit set, are handled.

Own Id: OTP-18878
Related Id(s): GH-7718, OTP-17734

The error information for erlang:phash/2 has been corrected.

Own Id: OTP-18904
Related Id(s): PR-7960

get_until requests using the I/O protocol now correctly return a binary or list when eof is the last item returned by the callback.

Own Id: OTP-18930
Related Id(s): GH-4992, PR-7993

Calling logger:add_handlers/1 with config option now works.

Own Id: OTP-18954
Related Id(s): GH-8061, PR-8076

The code:del_path/1 function now also works on paths added through -pa, -pz , -path and the boot script.

Own Id: OTP-18959
Related Id(s): GH-6692, PR-7697

A call to socket:[recv|recvfrom|recvmsg]/* with Timeout = 0 on Windows could cause a (case clause) crash if data is immediately available.

Own Id: OTP-19063
Related Id(s): OTP-18835

Improve heuristic for when a characters is wide in the shell for systems with old libc versions.

Own Id: OTP-19087
Related Id(s): PR-8382

Fix reading a line when reading from io:user/0 to not consider \r without \n to be a new line when erl is started with -noshell.

Own Id: OTP-19088
Related Id(s): GH-8360, PR-8396

Improvements and New Features

Added file:read_file/2 with a raw option for reading files without going through the file server.

Own Id: OTP-18589
Related Id(s): PR-7220

The undocumented Erlang DNS resolver library (inet_dns and inet_res) has been augmented to handle IXFR, NOTIFY, UPDATE and TSIG records. With this some bug fixes and code cleanup has been done, and the resolver used in the test suite has been changed to Knot DNS. See the source code.

Kudos to Alexander Clouter that did almost all the work!

Own Id: OTP-18713
Related Id(s): GH-6985, PR-6985

The ebin directories for escripts are now cached.

Own Id: OTP-18778
Related Id(s): PR-7556

-callback attributes haven been added to [application], [logger_handler], and [logger_formatter].

Own Id: OTP-18795
Related Id(s): PR-7703

Progress reports from before logger is started are now logged when log level is set to debug.

Own Id: OTP-18807
Related Id(s): ERIERL-985, PR-7732

The code:where_is_file/2 and code:which/1 functions now check for existence of the file directly instead of listing the content of each directory in the code path.

Own Id: OTP-18816
Related Id(s): PR-7711

Type specs has been added to the [logger:Level/1,2,3] functions.

Own Id: OTP-18820
Related Id(s): PR-7779

For inet_backend = socket, setting the active socket option alone, to once, true or N has been optimized, as well as the corresponding data delivery.

Own Id: OTP-18835

New functions socket:sendv/* for sending I/O vectors have been added.

Own Id: OTP-18845

The shell now pages long output from the documentation help command (h(Module)), auto completions and the search command.

Own Id: OTP-18846
Related Id(s): PR-7845

Native coverage support has been implemented in the JIT. It will automatically be used by the [cover] tool to reduce the execution overhead when running cover-compiled code.

There are also new APIs to support native coverage without using the cover tool.

To instrument code for native coverage it must be compiled with the [line_coverage] option.

To enable native coverage in the runtime system, start it like so:

text $ erl +JPcover true

There are also the following new functions for supporting native coverage:

code:coverage_support/0
code:get_coverage/2
code:reset_coverage/1
code:get_coverage_mode/0
code:get_coverage_mode/1
code:set_coverage_mode/1

Own Id: OTP-18856
Related Id(s): PR-7856

*** HIGHLIGHT ***

Optimized code loading by moving certain operations from the code server to the caller.

Own Id: OTP-18941
Related Id(s): PR-7981

The documentation has been migrated to use Markdown and ExDoc.

Own Id: OTP-18955
Related Id(s): PR-8026

*** HIGHLIGHT ***

Application startup has been optimized by removing an intermediary process.

Own Id: OTP-18963
Related Id(s): PR-8042

The existing experimental support for archive files will be changed in a future release. The support for having an archive in an escript will remain, but the support for using archives in a release will either become more limited or completely removed.

As of Erlang/OTP 27, the function code:lib_dir/2, the -code_path_choice flag, and using [erl_prim_loader] for reading members of an archive are deprecated.

Own Id: OTP-18966
Related Id(s): PR-8091

*** POTENTIAL INCOMPATIBILITY ***

The undocumented and deprecated file:pid2name function has been removed.

Own Id: OTP-18967
Related Id(s): PR-8092

There is a new module [trace] in Kernel providing the same trace functionality as erlang:trace/3 and erlang:trace_pattern/3, but with the addition of dynamic isolated trace sessions.

Own Id: OTP-18980
*** HIGHLIGHT ***

Error logging has been improved when the io:standard_io/0 reader and/or writer terminates with an error.

Own Id: OTP-18989
Related Id(s): PR-8103

inet_backend = socket has been optimized and reworked to be more compatible with the original inet_backend = inet.

Own Id: OTP-19004
Related Id(s): OTP-18835

Add an simple example (echo server) )to the socket users guide.

Own Id: OTP-19042

inet:i/0,1,2 has been improved to allow port numbers to be shown explicitly.

Own Id: OTP-19053
Related Id(s): #6724

The socket documentation has been reworked, and due to that a few details were fixed:
socket:is_supported/1 now returns true for example for protocols that is a "category", not an item.
socket:cancel_monitor/1 no longer badargs for a monitor that was set by another process, instead it returns false as for other unknown reference()s.

Own Id: OTP-19054

Add stdin, stdout and stderr keys to io:getopts/1 on io:standard_io/0 to indicate if the respective I/O device is backed by a terminal.

Own Id: OTP-19089
Related Id(s): PR-8396

Full runtime dependencies of kernel-10.0

crypto-5.0, erts-15.0, sasl-3.0, stdlib-6.0

megaco-4.6

Improvements and New Features

-callback attributes have been added to [megaco_transport].

Own Id: OTP-18806
Related Id(s): PR-7740

Updated types and specs for all API modules.

Own Id: OTP-18920
Related Id(s): BL-322

The documentation has been migrated to use Markdown and ExDoc.

Own Id: OTP-18955
Related Id(s): PR-8026

*** HIGHLIGHT ***

Full runtime dependencies of megaco-4.6

asn1-3.0, debugger-4.0, erts-12.0, et-1.5, kernel-8.0, runtime_tools-1.8.14, stdlib-2.5

mnesia-4.23.2

Fixed Bugs and Malfunctions

The mnesia_registry module have been deprecated.

Own Id: OTP-18994

Improvements and New Features

The documentation has been migrated to use Markdown and ExDoc.

Own Id: OTP-18955
Related Id(s): PR-8026

*** HIGHLIGHT ***

Full runtime dependencies of mnesia-4.23.2

erts-9.0, kernel-5.3, stdlib-5.0

observer-2.16

Fixed Bugs and Malfunctions

The dependencies for this application are now listed in the app file.

Own Id: OTP-18831
Related Id(s): PR-7441

Improvements and New Features

The new function proc_lib:set_label/1 can be used to add a descriptive term to any process that does not have a registered name. The name will be shown by tools such as \c:i/0, [observer], and it will be included in crash reports produced by processes using [gen_server], [gen_statem], [gen_event], and [gen_fsm].

The label for a process can be retrieved by calling proc_lib:get_label/1.

Note that those functions work on any process, not only processes that use [proc_lib].

Example:

text 1> self(). <0.90.0> 2> proc_lib:set_label(my_label). ok 3> i(). . . . <0.90.0> erlang:apply/2 2586 75011 0 my_label c:pinfo/2 51 4> proc_lib:get_label(self()). my_label

Own Id: OTP-18789
Related Id(s): PR-7720, PR-8003

The documentation has been migrated to use Markdown and ExDoc.

Own Id: OTP-18955
Related Id(s): PR-8026

*** HIGHLIGHT ***

m:etop has been updated to use dbg:session/2 in order to not interfere with any other tracing.

Own Id: OTP-19082
Related Id(s): PR-8363

Full runtime dependencies of observer-2.16

erts-15.0, et-1.5, kernel-10.0, runtime_tools-2.1, stdlib-5.0, wx-2.3

odbc-2.14.3

Fixed Bugs and Malfunctions

The order of libs in the Makefile has been changed to avoid finding the system's libei instead of Erlang's libei.

Own Id: OTP-19030
Related Id(s): GH-8244, PR-8258

Improvements and New Features

The documentation has been migrated to use Markdown and ExDoc.

Own Id: OTP-18955
Related Id(s): PR-8026

*** HIGHLIGHT ***

Full runtime dependencies of odbc-2.14.3

erts-6.0, kernel-3.0, stdlib-2.0

os_mon-2.10

Improvements and New Features

Function specifications and types have been added to all public API functions.

Own Id: OTP-18913

The documentation has been migrated to use Markdown and ExDoc.

Own Id: OTP-18955
Related Id(s): PR-8026

*** HIGHLIGHT ***

Full runtime dependencies of os_mon-2.10

erts-14.0, kernel-9.0, sasl-4.2.1, stdlib-5.0

parsetools-2.6

Improvements and New Features

The leex documentation has been updated to use specs for documenting the generated interface.

Own Id: OTP-18796
Related Id(s): PR-7703

yecc now wraps the -module attribute with -file to indicate the .yrl source file.

Own Id: OTP-18912
Related Id(s): PR-7963

The documentation has been migrated to use Markdown and ExDoc.

Own Id: OTP-18955
Related Id(s): PR-8026

*** HIGHLIGHT ***

Full runtime dependencies of parsetools-2.6

erts-6.0, kernel-3.0, stdlib-3.4

public_key-1.16

Improvements and New Features

The ssl client can negotiate and handle certificate status request (OCSP stapling support on the client side).

Thanks to voltone for interop testing and related discussions.

Own Id: OTP-18606
Related Id(s): OTP-16448, OTP-16875

*** HIGHLIGHT ***

The exception reason when public_key:cacerts_get/0 failed has been improved.

Own Id: OTP-18609
Related Id(s): GH-7295, PR-7302

Key customization support has been extended to allow flexibility for implementers of for instance hardware security modules (HSM) or trusted platform modules (TPM).

Own Id: OTP-18876
Related Id(s): PR-7475, PR-7898

The documentation has been migrated to use Markdown and ExDoc.

Own Id: OTP-18955
Related Id(s): PR-8026

*** HIGHLIGHT ***

The existing function ssl:key_exporter_materials/4 is now documented and supported.

Own Id: OTP-19016
Related Id(s): PR-8233

*** POTENTIAL INCOMPATIBILITY ***

Due to another attack on PKCS #1 v1.5 padding, known as the Marvin attack, about which we were alerted by Hubert Kario from Red Hat. You can find more details about the attack at https://people.redhat.com/~hkario/marvin/ Functions that may be vulnerable are now deprecated.

Note that you might mitigate the problem by using appropriate versions of OpenSSL together with our software, but we recommend not using them at all.

Also avoid using TLS versions prior to TLS-1.2 (not supported by default) and do not enable RSA-key exchange cipher suites (not supported by default).

Own Id: OTP-19075
*** POTENTIAL INCOMPATIBILITY ***

Full runtime dependencies of public_key-1.16

asn1-3.0, crypto-4.6, erts-6.0, kernel-3.0, stdlib-3.5

reltool-1.0.1

Fixed Bugs and Malfunctions

The dependencies for this application are now listed in the app file.

Own Id: OTP-18831
Related Id(s): PR-7441

Improvements and New Features

The documentation has been migrated to use Markdown and ExDoc.

Own Id: OTP-18955
Related Id(s): PR-8026

*** HIGHLIGHT ***

Full runtime dependencies of reltool-1.0.1

erts-15.0, kernel-9.0, sasl-4.2.1, stdlib-5.0, tools-2.6.14, wx-2.3

runtime_tools-2.1

Improvements and New Features

The [instrument] module can now track allocations on a per-process or per-port basis.

Own Id: OTP-18577
Related Id(s): PR-7236

The new function proc_lib:set_label/1 can be used to add a descriptive term to any process that does not have a registered name. The name will be shown by tools such as \c:i/0, [observer], and it will be included in crash reports produced by processes using [gen_server], [gen_statem], [gen_event], and [gen_fsm].

The label for a process can be retrieved by calling proc_lib:get_label/1.

Note that those functions work on any process, not only processes that use [proc_lib].

Example:

text 1> self(). <0.90.0> 2> proc_lib:set_label(my_label). ok 3> i(). . . . <0.90.0> erlang:apply/2 2586 75011 0 my_label c:pinfo/2 51 4> proc_lib:get_label(self()). my_label

Own Id: OTP-18789
Related Id(s): PR-7720, PR-8003

Type specs had been added to all [dbg] functions.

Own Id: OTP-18859
Related Id(s): PR-7782

The documentation has been migrated to use Markdown and ExDoc.

Own Id: OTP-18955
Related Id(s): PR-8026

*** HIGHLIGHT ***

m:dbg have been updated to use trace sessions.

dbg:session_create/1, dbg:session/2, and dbg:session_destroy/1 have been added to work sessions. See the documentation for details.

Own Id: OTP-19081
Related Id(s): PR-8363

Full runtime dependencies of runtime_tools-2.1

erts-15.0, kernel-10.0, mnesia-4.12, stdlib-6.0

sasl-4.2.2

Improvements and New Features

The documentation has been migrated to use Markdown and ExDoc.

Own Id: OTP-18955
Related Id(s): PR-8026

*** HIGHLIGHT ***

Full runtime dependencies of sasl-4.2.2

erts-15.0, kernel-6.0, stdlib-4.0, tools-2.6.14

snmp-5.16

Improvements and New Features

-callback attributes have been added to modules [snmpa_network_interface_filter], [snmpa_notification_filter], [snmpm_network_interface_filter], [snmpm_user], and [snmpa_notification_delivery_info_receiver].

New -type attributes have also been added to modules [snmp], [snmpa], [snmpm], and [snmpa_conf] to support the previously mentioned callbacks.

Own Id: OTP-18785
Related Id(s): PR-7702

Updated types and specs for all API modules.

Own Id: OTP-18934
Related Id(s): BL-312

The documentation has been migrated to use Markdown and ExDoc.

Own Id: OTP-18955
Related Id(s): PR-8026

*** HIGHLIGHT ***

Full runtime dependencies of snmp-5.16

crypto-4.6, erts-12.0, kernel-8.0, mnesia-4.12, runtime_tools-1.8.14, stdlib-5.0

ssh-5.2

Fixed Bugs and Malfunctions

SSH processes are now assigned labels for troubleshooting purposes.

Own Id: OTP-19017
Related Id(s): PR-8249

With this change, ssh client will automatically adjust transfer window size for commands executed remotely over SSH.

Own Id: OTP-19057
Related Id(s): GH-7483, PR-8345

Improvements and New Features

The shell now pages long output from the documentation help command (h(Module)), auto completions and the search command.

Own Id: OTP-18846
Related Id(s): PR-7845

The documentation has been migrated to use Markdown and ExDoc.

Own Id: OTP-18955
Related Id(s): PR-8026

*** HIGHLIGHT ***

Updated types and specs for all API modules.

Own Id: OTP-18961

Full runtime dependencies of ssh-5.2

crypto-5.0, erts-14.0, kernel-9.0, public_key-1.6.1, runtime_tools-1.15.1, stdlib-5.0, stdlib-6.0

ssl-11.2

Fixed Bugs and Malfunctions

Starting a TLS server without sufficient credentials (certificate or anonymous cipher) would work, but it was impossible to connect to it.

This has been corrected to return an error instead of starting the server.

Own Id: OTP-18887
Related Id(s): GH-7493, PR-7918

ASN.1 decoding errors are handled in more places to ensure that errors are returned instead of cause a crash.

Own Id: OTP-18969
Related Id(s): GH-8058, PR-8256

Improved error checking on the API functions.

Own Id: OTP-18992
Related Id(s): GH-8066, PR-8156

Improvements and New Features

The ssl client can negotiate and handle certificate status request (OCSP stapling support on the client side).

Thanks to voltone for interop testing and related discussions.

Own Id: OTP-18606
Related Id(s): OTP-16448, OTP-16875

*** HIGHLIGHT ***

Memory consumption has been reduced and performance increased by refactoring internal data structures and their usage.

Own Id: OTP-18665
Related Id(s): PR-7447

Added ssl_crl_cache_api:lookup/2 as an optional -callback attribute.

Own Id: OTP-18788
Related Id(s): PR-7700

Key customization support has been extended to allow flexibility for implementers of for instance hardware security modules (HSM) or trusted platform modules (TPM).

Own Id: OTP-18876
Related Id(s): PR-7475, PR-7898

The proc_lib:set_label/1 function is now used to increase observability of ssl processes.

Own Id: OTP-18879

Brainpool elliptic curves are now supported in TLS-1.3.

Own Id: OTP-18884
Related Id(s): PR-8056

The documentation has been migrated to use Markdown and ExDoc.

Own Id: OTP-18955
Related Id(s): PR-8026

*** HIGHLIGHT ***

For security reasons, the CBC ciphers are now longer included in the list of default ciphers for TLS-1.2.

Own Id: OTP-19025
Related Id(s): PR-8250

*** HIGHLIGHT ***

*** POTENTIAL INCOMPATIBILITY ***

There is a new cert_policy_opts option to configure certificate policy options for the certificate path validation.

Own Id: OTP-19027
Related Id(s): PR-8255

Full runtime dependencies of ssl-11.2

crypto-5.0, erts-15.0, inets-5.10.7, kernel-9.0, public_key-1.15, runtime_tools-1.15.1, stdlib-6.0

stdlib-6.0

Fixed Bugs and Malfunctions

The specs in module [binary] has been updated to reflect what is allowed by the documentation.

Own Id: OTP-18684
Related Id(s): PR-7481

Several functions in the [binary] module would accept arguments of the wrong type under certain circumstances. In this release, they now raise an exception when incorrect types are given.

The following functions would accept an invalid pattern if the subject binary was empty or if the {scope,{0,0}} option was given: binary:match/2,3, binary:matches/2,3, binary:replace/3,4, and binary:split/2,3

The call binary:copy(<<1:1>>, 0) would return an empty binary instead of raising an exception. Similarly, calls to binary:part/2,3 attempting to extract 0 bytes at position 0 of a bitstring would return an empty binary instead of raising an exception.

Own Id: OTP-18743
Related Id(s): PR-7607, PR-7628

The documentation for the preprocessor now mentions that defined(Name) can be called in the condition for an -if or -elif directive to test whether Name is the name of a defined macro. (This feature was implemented in OTP 21.)

Own Id: OTP-18784
Related Id(s): GH-7706, PR-7726

*** POTENTIAL INCOMPATIBILITY ***

get_until requests using the I/O protocol now correctly return a binary or list when eof is the last item returned by the callback.

Own Id: OTP-18930
Related Id(s): GH-4992, PR-7993

The error handling the simple_one_for_one supervisor has been enhanced. A transient child returning ignore will no longer cause a crash.

Also, automatic shutdown has been disabled because it does not make sense for this supervisor type. That is was allowed is considered a bug. Therefore, we don't consider this an incompatible change.

Own Id: OTP-19029
Related Id(s): PR-8230

*** POTENTIAL INCOMPATIBILITY ***

Fix shell expansion to not crash when expanding a map with non-atom keys and to not list zero arity functions when an argument has been given.

Own Id: OTP-19073
Related Id(s): GH-8364, GH-8365, GH-8366, PR-8375

Improvements and New Features

The functions is_equal/2, map/2, and filtermap/2 have been added to the modules [sets], [ordsets], and [gb_sets].

Own Id: OTP-18622
Related Id(s): PR-7183, PR-7232

*** HIGHLIGHT ***

The compiler now emits nicer error message for function head mismatches. For example, given:

erlang a() -> ok; a(_) -> error.

Erlang/OTP 26 and earlier would emit a diagnostic similar to:

text t.erl:6:1: head mismatch % 6| a(_) -> error. % | ^

while in Erlang/OTP 27 the diagnostic is similar to:

Own Id: OTP-18648
Related Id(s): PR-7383

*** HIGHLIGHT ***

zip:create/2,3 will now tolerate POSIX timestamps in the provided file_info records.

Own Id: OTP-18668

The callback function gen_statem:handle_event/4 has been cached in the gen_statem engine to optimize callback call speed.

Own Id: OTP-18671
Related Id(s): PR-7419

The type beam_lib:beam/0 is now exported.

Own Id: OTP-18716
Related Id(s): PR-7534

The documentation for the [binary] module has been improved.

Own Id: OTP-18741
Related Id(s): PR-7585

binary:replace/3,4 now supports using a fun for supplying the replacement binary.

Own Id: OTP-18742
Related Id(s): PR-7590

Triple-Quoted Strings has been implemented as per EEP 64. See String in the Reference Manual.

Example:

erlang 1> """ a b c """. "a\nb\nc"

Adjacent string literals without intervening white space is now a syntax error, to avoid possible confusion with triple-quoted strings. For example:

```erlang 1> "abc""xyz". "xyz".

1:6: adjacent string literals without intervening white space ```

Own Id: OTP-18750
Related Id(s): PR-7313, PR-7451, OTP-18746

*** HIGHLIGHT ***

*** POTENTIAL INCOMPATIBILITY ***

The new function proc_lib:set_label/1 can be used to add a descriptive term to any process that does not have a registered name. The name will be shown by tools such as \c:i/0, [observer], and it will be included in crash reports produced by processes using [gen_server], [gen_statem], [gen_event], and [gen_fsm].

The label for a process can be retrieved by calling proc_lib:get_label/1.

Note that those functions work on any process, not only processes that use [proc_lib].

Example:

text 1> self(). <0.90.0> 2> proc_lib:set_label(my_label). ok 3> i(). . . . <0.90.0> erlang:apply/2 2586 75011 0 my_label c:pinfo/2 51 4> proc_lib:get_label(self()). my_label

Own Id: OTP-18789
Related Id(s): PR-7720, PR-8003

-callback attributes has been added to modules [sys] and [erl_error].

Own Id: OTP-18793
Related Id(s): PR-7703

Several new functions that accept funs have been added to module [timer].

Own Id: OTP-18808
Related Id(s): PR-7649

*** HIGHLIGHT ***

Sigils on string literals have been implemented as per EEP 66, that is: binary and string sigils in verbatim and escape characters variants, as well as a default (vanilla) Sigil. All for ordinary strings and for triple-quoted strings (EEP 64). See Sigils in the Reference Manual.

Examples:

erlang 1> ~"Björn". <<"Björn"/utf8>> 2> ~b"Björn". <<"Björn"/utf8>> 3> ~S"\s*(\w+)". "\\s*(\\w+)" 4> ~B"\s*(\w+)". <<"\\s*(\\w+)">>

Own Id: OTP-18825
Related Id(s): PR-7684, OTP-18750

*** HIGHLIGHT ***

Functions shell:default_multiline_prompt/1, shell:inverted_space_prompt/1, and shell:prompt_width/1 have been exported to help with custom prompt implementations.

Own Id: OTP-18834
Related Id(s): PR-7675, PR-7816

The shell now pages long output from the documentation help command (h(Module)), auto completions and the search command.

Own Id: OTP-18846
Related Id(s): PR-7845

The M-h hotkey (Alt/Option-h) now outputs help for the module or function directly before the cursor.

Own Id: OTP-18847
Related Id(s): PR-7846

Added support for adding a custom code formatter that formats your multi-line shell commands in your preferred formatting on submission. See shell:format_shell_func/ and shell:erl_pp_format_func/1.

Own Id: OTP-18848
Related Id(s): PR-7847

Added shell functions for viewing, forgetting and saving locally defined functions, types and records.

Own Id: OTP-18852
Related Id(s): PR-7844

Added string:jaro_similarity/2, which can be used to calculate the similarity between two strings.

Own Id: OTP-18865
Related Id(s): PR-7879

The new function ets:update_element/4 is similar to ets:update_element/3, but takes a default tuple as the fourth argument, which will be inserted if no previous record with that key exists.

Own Id: OTP-18870
Related Id(s): PR-7857

Added functions to retrieve the next higher or lower key/element from [gb_trees] and [gb_sets], as well as returning iterators that start at given keys/elements.

Own Id: OTP-18874
Related Id(s): PR-7745

When the shell built-in function c/1,2 is used to re-compile a module, the current working directory of the original compilation is now added to the include path.

Own Id: OTP-18908
Related Id(s): PR-7957

The timer module now uses a private table for its internal state, slightly improving its performance.

Own Id: OTP-18914
Related Id(s): PR-7973

EEP-59 - Documentation Attributes has been implemented.

Types, callbacks, and function documentation can be set to hidden either via -doc false or -doc hidden. When documentation attributes mark a type as hidden, they will not be part of the documentation.
The documentation from moduledoc and doc gets added by default to the binary beam file, following the format of EEP-48.
Using the compiler flag warn_missing_doc will raise a warning when -doc attributes are missing in exported functions, types, and callbacks.
Using the compiler flag warn_missing_spec_documented will raise a warning when spec attributes are missing in documented functions, types, and callbacks.
moduledocs and docs may refer to external files to be embedded, such as -doc {file, "README.md"}., which refers to the file README.md found in the current working directory.
The compiler warns about exported functions whose specs refer to hidden types. Thus, there will be warnings when a hidden type (meaning, the type is not part of the documentation) gets used in an exported function.

Own Id: OTP-18916
Related Id(s): PR-7936

*** HIGHLIGHT ***

New [ets] functions ets:first_lookup/1, ets:next_lookup/2, ets:prev_lookup/2 and ets:last_lookup/1. Example: ets:next_lookup/1 is equivalent to ets:next/2 followed by ets:lookup/2 with the next key. The new combined functions are more efficient and with guaranteed atomicity.

Own Id: OTP-18923
Related Id(s): PR-6791

*** HIGHLIGHT ***

The maybe expression is now enabled by default.

erlang -feature(maybe_expr, disable).

Another way to disable the maybe_expr feature is by passing the -disable-feature option to erlc:

text erlc -disable-feature maybe_expr some_file.erl

Own Id: OTP-18944
Related Id(s): PR-8067

*** HIGHLIGHT ***

The compiler will now raise a warning when updating record/map literals. As an example, consider this module:

```erlang -module(t). -export([f/0]). -record(r, {a,b,c}).

f() -> #r{a=1}#r{b=2}. ```

The compiler raises the following warning:

text 1> c(t). t.erl:6:12: Warning: expression updates a literal % 6| #r{a=1}#r{b=2}. % | ^

Own Id: OTP-18951
Related Id(s): PR-8069

The documentation has been migrated to use Markdown and ExDoc.

Own Id: OTP-18955
Related Id(s): PR-8026

*** HIGHLIGHT ***

Optimized ets:foldl and ets:foldr to use new ets:next_lookup. Also made them immune against table renaming.

Own Id: OTP-18993
Related Id(s): PR-8048

Windows now supports all functions in [math].

Own Id: OTP-19001
Related Id(s): PR-8164

m:erl_lint (and by extension the [compiler]) will now warn for code using deprecated callbacks.

The only callback currenly deprecated is format_status/2 in gen_server, gen_event and gen_statem.

You can use nowarn_deprecated_callback to silence the warning.

Own Id: OTP-19010
Related Id(s): PR-8205

There is a new module [json] for encoding and decoding JSON.

Both encoding and decoding can be customized. Decoding can be done in a SAX-like fashion and handle multiple documents and streams of data.

Own Id: OTP-19020
Related Id(s): PR-8111

*** HIGHLIGHT ***

Full runtime dependencies of stdlib-6.0

compiler-5.0, crypto-4.5, erts-15.0, kernel-10.0, sasl-3.0

syntax_tools-3.2

Fixed Bugs and Malfunctions

The [epp_dodger] module can now handle the maybe and else keywords.

Own Id: OTP-18608
Related Id(s): GH-7266, PR-7267

Reverting a #wrapper will no longer throw away changes made to positions/annotations.

Own Id: OTP-18805
Related Id(s): PR-7398

Improvements and New Features

The type erl_syntax:annotation_or_location/0 is now exported.

Own Id: OTP-18715
Related Id(s): PR-7535

The documentation has been migrated to use Markdown and ExDoc.

Own Id: OTP-18955
Related Id(s): PR-8026

*** HIGHLIGHT ***

Full runtime dependencies of syntax_tools-3.2

compiler-7.0, erts-9.0, kernel-5.0, stdlib-4.0

tftp-1.2

Improvements and New Features

There is a new [tftp_logger] callback behavior module.

Own Id: OTP-18787
Related Id(s): PR-7700

The documentation has been migrated to use Markdown and ExDoc.

Own Id: OTP-18955
Related Id(s): PR-8026

*** HIGHLIGHT ***

Full runtime dependencies of tftp-1.2

erts-6.0, kernel-6.0, stdlib-5.0

tools-4.0

Fixed Bugs and Malfunctions

Dialyzer warnings due to type specs added in [dbg] have been eliminated.

Own Id: OTP-18860

In Erlang/OTP 26, doing a [cover] analysis on the line level would return multiple entries for lines on which multiple functions were defined.

For example, consider this module:

  -module(foo).
  -export([bar/0, baz/0]).

  bar() -> ok. baz() -> not_ok.

{% raw %}

In Erlang/OTP 26, analysing on the line level would return two entries for line 4:

  1> cover:compile_module(foo).
  {ok,foo}
  2> foo:bar().
  ok
  3> cover:analyse(foo, coverage, line).
  {ok,[{{foo,4},{1,0}},{{foo,4},{0,1}}]}
  4> cover:analyse(foo, calls, line).
  {ok,[{{foo,4},1},{{foo,4},0}]}

In Erlang/OTP 27, there will only be a single entry for line 4:

  1> cover:compile_module(foo).
  {ok,foo}
  2> foo:bar().
  ok
  3> cover:analyse(foo, coverage, line).
  {ok,[{{foo,4},{1,0}}]}
  4> cover:analyse(foo, calls, line).
  {ok,[{{foo,4},1}]}

{% endraw %}

Own Id: OTP-18998
Related Id(s): GH-8159, PR-8182

Fixed align command in emacs mode.

Own Id: OTP-19026
Related Id(s): PR-8155

Improvements and New Features

Triple-Quoted Strings has been implemented as per EEP 64. See String in the Reference Manual.

Example:

erlang 1> """ a b c """. "a\nb\nc"

Adjacent string literals without intervening white space is now a syntax error, to avoid possible confusion with triple-quoted strings. For example:

```erlang 1> "abc""xyz". "xyz".

1:6: adjacent string literals without intervening white space ```

Own Id: OTP-18750
Related Id(s): PR-7313, PR-7451, OTP-18746

*** HIGHLIGHT ***

*** POTENTIAL INCOMPATIBILITY ***

There is a new tool [tprof], which combines the functionality of [eprof] and [cprof] under one interface and adds heap profiling. It also has functionality to help with profiling process hierarchies.

Example:

```erlang 1> tprof:profile(lists, seq, [1, 16], #{type => call_memory}).

** Process <0.92.0> -- 100.00% of total *** FUNCTION CALLS WORDS PER CALL [ %] lists:seq_loop/3 5 32 6.40 [100.00] 32 [ 100.0] ok ```

Own Id: OTP-18756
Related Id(s): PR-6639

*** HIGHLIGHT ***

Native coverage support has been implemented in the JIT. It will automatically be used by the [cover] tool to reduce the execution overhead when running cover-compiled code.

There are also new APIs to support native coverage without using the cover tool.

To instrument code for native coverage it must be compiled with the [line_coverage] option.

To enable native coverage in the runtime system, start it like so:

text $ erl +JPcover true

There are also the following new functions for supporting native coverage:

code:coverage_support/0
code:get_coverage/2
code:reset_coverage/1
code:get_coverage_mode/0
code:get_coverage_mode/1
code:set_coverage_mode/1

Own Id: OTP-18856
Related Id(s): PR-7856

*** HIGHLIGHT ***

The documentation has been migrated to use Markdown and ExDoc.

Own Id: OTP-18955
Related Id(s): PR-8026

*** HIGHLIGHT ***

Improved the align command in emacs mode.

Own Id: OTP-19080
Related Id(s): PR-8288

Full runtime dependencies of tools-4.0

compiler-8.5, erts-15.0, erts-15.0, kernel-10.0, runtime_tools-2.1, stdlib-6.0

wx-2.4.2

Improvements and New Features

The documentation has been migrated to use Markdown and ExDoc.

Own Id: OTP-18955
Related Id(s): PR-8026

*** HIGHLIGHT ***

Full runtime dependencies of wx-2.4.2

erts-12.0, kernel-8.0, stdlib-5.0

xmerl-2.0

Fixed Bugs and Malfunctions

Some default values in Xmerl has been changed to avoid XML External Entity (XXE) vulnerabilities if you're parsing untrusted XML.

xmerl_scan: the default value for allow_entities has changed to false. xmerl_sax_parser: the default value for external_entities has changed to none.

Own Id: OTP-19079
Related Id(s): GH-7539

*** POTENTIAL INCOMPATIBILITY ***

An event state in xmerl_sax_parser which was updated in the event callback for a startEntity was not saved.

Own Id: OTP-19086
Related Id(s): GH-8452

Improvements and New Features

Function specifications and types have been added to all public API functions.

Own Id: OTP-18913

As an alternative to xmerl_xml, a new export module xmerl_xml_indent that provides out-of-the box indented output has been added.

Own Id: OTP-18922
Related Id(s): PR-7942

The documentation has been migrated to use Markdown and ExDoc.

Own Id: OTP-18955
Related Id(s): PR-8026

*** HIGHLIGHT ***

Full runtime dependencies of xmerl-2.0

erts-6.0, kernel-3.0, stdlib-2.5

Thanks to

Alexander Clouter, Andrea Leopardi, Angelo Lakra, Anshul Mittal (WhatsApp), Anupama Singh, Artem Solomatin, Benjamin Philip, chiroptical, Christian Flicker, Fabian N.C. van 't Hooft, Frej Drejhammar, Gilbert, Guilherme Andrade, Gustaw Lippa, Ildar Khizbulin, Ilya Klyuchnikov, Ivan Sokolov, Jakub Witczak, Jan Uhlig, jdamanalo, jianhui, João Henrique Ferreira de Freitas, Johannes Christ, Jonatan Männchen, Jonathan Arnett, José Valim, Jurek Michal-AMJ018, lexprfuncall, LJZN, Luca Succi, Łukasz Niemier, Marcelino Alberdi Pereira, Maria Scott, Marko Mindek, Matthew Pope, Maxim Fedorov, Max Nordlund kivra, M-I, Michael Davis, Michal Jurek, Michal Kuratczyk, Michał Muskała, Nelson Vides, neo, Nikolay Amiantov, Paul Guyot, Paulo F. Oliveira, Richard Carlsson, Roberto Aloi, Robin Morisset, Ryota Kinukawa, Sacha, Sergey Yelin, Takeru Ohta, Tomas Abrahamsson, William Fank Thomé, WLSF, yastanotheruser, zeyun chen, Zeyu Zhang

Source: OTP-27.0.README.md, updated 2024-08-13

Erlang/OTP Files

Build massively scalable soft real-time systems

Get an email when there's a new version of Erlang/OTP

HIGHLIGHTS

POTENTIAL INCOMPATIBILITIES

OTP-27.0

Fixed Bugs and Malfunctions

Improvements and New Features

asn1-5.3

Fixed Bugs and Malfunctions

Improvements and New Features

Full runtime dependencies of asn1-5.3

common_test-1.27

Improvements and New Features

Full runtime dependencies of common_test-1.27

compiler-8.5

Fixed Bugs and Malfunctions

Improvements and New Features

Full runtime dependencies of compiler-8.5

crypto-5.5

Improvements and New Features

Full runtime dependencies of crypto-5.5

debugger-5.4

Fixed Bugs and Malfunctions

Improvements and New Features

Full runtime dependencies of debugger-5.4

dialyzer-5.2

Improvements and New Features

Full runtime dependencies of dialyzer-5.2

diameter-2.4

Improvements and New Features

Full runtime dependencies of diameter-2.4

edoc-1.3

Fixed Bugs and Malfunctions

Improvements and New Features

Full runtime dependencies of edoc-1.3

eldap-1.2.13

Improvements and New Features

Full runtime dependencies of eldap-1.2.13

erl_interface-5.5.2

Improvements and New Features

Known Bugs and Problems

erts-15.0

Fixed Bugs and Malfunctions

Improvements and New Features

Full runtime dependencies of erts-15.0

et-1.7.1

Fixed Bugs and Malfunctions

Improvements and New Features

Full runtime dependencies of et-1.7.1

eunit-2.9.1

Improvements and New Features

Full runtime dependencies of eunit-2.9.1

ftp-1.2.2

Fixed Bugs and Malfunctions

Improvements and New Features

Full runtime dependencies of ftp-1.2.2

inets-9.2

Improvements and New Features

Full runtime dependencies of inets-9.2

jinterface-1.14.1

Improvements and New Features

kernel-10.0

Fixed Bugs and Malfunctions

Improvements and New Features

Full runtime dependencies of kernel-10.0

megaco-4.6

Improvements and New Features

Full runtime dependencies of megaco-4.6

mnesia-4.23.2

Fixed Bugs and Malfunctions

Improvements and New Features

Full runtime dependencies of mnesia-4.23.2

observer-2.16

Fixed Bugs and Malfunctions

Improvements and New Features

Full runtime dependencies of observer-2.16

odbc-2.14.3

Fixed Bugs and Malfunctions

Improvements and New Features