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</header>
<p>This document describes the changes made to the ERTS application.</p>
+<section><title>Erts 6.1.2</title>
+
+ <section><title>Fixed Bugs and Malfunctions</title>
+ <list>
+ <item>
+ <p>
+ OTP-11850 fixed filelib:wildcard/1 to work with broken
+ symlinks. This correction, however, introduced problems
+ since symlinks were no longer followed for functions like
+ filelib:ensure_dir/1, filelib:is_dir/1,
+ filelib:file_size/1, etc. This is now corrected.</p>
+ <p>
+ Own Id: OTP-12054 Aux Id: seq12660 </p>
+ </item>
+ </list>
+ </section>
+
+</section>
+
+<section><title>Erts 6.1.1</title>
+
+ <section><title>Fixed Bugs and Malfunctions</title>
+ <list>
+ <item>
+ <p>
+ Fixed ETHR_FORCE_INLINE which caused the build to break
+ on some platforms without adequate thread support
+ (VxWorks).</p>
+ <p>
+ Own Id: OTP-12010</p>
+ </item>
+ </list>
+ </section>
+
+</section>
+
+<section><title>Erts 6.1</title>
+
+ <section><title>Fixed Bugs and Malfunctions</title>
+ <list>
+ <item>
+ <p>The documentation for <c>spawn_opt/5</c> now has a
+ note mentioning that the <c>monitor</c> option is not
+ supported.</p>
+ <p>
+ Own Id: OTP-11849</p>
+ </item>
+ <item>
+ <p>
+ Fix broken system monitoring of <c>large_heap</c> for
+ non-smp VM. No message for <c>large_heap</c> was ever
+ sent on non-smp VM. Bug exist since R16B.</p>
+ <p>
+ Own Id: OTP-11852</p>
+ </item>
+ <item>
+ <p>
+ The emulator without SMP support crashed when passing a
+ message to a process without enough heap space for the
+ message. This bug was introduced in <c>erts-6.0</c>.</p>
+ <p>
+ Own Id: OTP-11887 Aux Id: OTP-11388 </p>
+ </item>
+ <item>
+ <p>
+ Fix race between ETS table deletion and unfixation that
+ could cause VM crash. The race could happen between a
+ terminating process that does not own the table but has a
+ fixation on it and another process that deletes the table
+ (maybe the owner terminating) at the same time. Bug
+ existed since R15B02.</p>
+ <p>
+ Own Id: OTP-11892</p>
+ </item>
+ <item>
+ <p>The string following the <c>-eval</c> option when
+ invoking <c>erl</c> would not be properly translated from
+ UTF-8 to a list of Unicode characters (as would the
+ arguments for <c>-run</c>).</p>
+ <p>That bug would cause the build of Erlang/OTP to fail
+ when building in a directory whose pathname contained
+ non-US ASCII characters encoded in UTF-8. (Thanks to Eric
+ Pailleau for reporting this bug.)</p>
+ <p>
+ Own Id: OTP-11916</p>
+ </item>
+ <item>
+ <p>
+ Fix erts_debug:size/1 to handle Map sizes</p>
+ <p>
+ Own Id: OTP-11923</p>
+ </item>
+ <item>
+ <p>
+ Removed <c>erlang:bitstr_to_list/1</c> and
+ <c>erlang:list_to_bitstr/1</c>. They were added by
+ mistake, and have always raised an <c>undefined</c>
+ exception when called.</p>
+ <p>
+ Own Id: OTP-11942</p>
+ </item>
+ <item>
+ <p>
+ Fixed compilation using mingw-w64 on Windows.</p>
+ <p>
+ Thanks to Jani Hakala.</p>
+ <p>
+ Own Id: OTP-11945</p>
+ </item>
+ <item>
+ <p>
+ The git sha is no longer printed in the shell start
+ header when erlang is built from a tagged git release.</p>
+ <p>
+ Own Id: OTP-11961</p>
+ </item>
+ <item>
+ <p>
+ Fixed a bug where <c>send</c> trace events were
+ erroneously dropped when the send was done to a
+ registered process. This bug was introduced in R16B.</p>
+ <p>
+ Own Id: OTP-11968</p>
+ </item>
+ </list>
+ </section>
+
+
+ <section><title>Improvements and New Features</title>
+ <list>
+ <item>
+ <p>The following native functions now bump an appropriate
+ amount of reductions and yield when out of
+ reductions:</p> <list>
+ <item><c>erlang:binary_to_list/1</c></item>
+ <item><c>erlang:binary_to_list/3</c></item>
+ <item><c>erlang:bitstring_to_list/1</c></item>
+ <item><c>erlang:list_to_binary/1</c></item>
+ <item><c>erlang:iolist_to_binary/1</c></item>
+ <item><c>erlang:list_to_bitstring/1</c></item>
+ <item><c>binary:list_to_bin/1</c></item> </list>
+ <p>Characteristics impact:</p> <taglist>
+ <tag>Performance</tag> <item>The functions converting
+ from lists got a performance loss for very small lists,
+ and a performance gain for very large lists.</item>
+ <tag>Priority</tag> <item>Previously a process executing
+ one of these functions effectively got an unfair priority
+ boost. This priority boost depended on the input size.
+ The larger the input was, the larger the priority boost
+ got. This unfair priority boost is now lost. </item>
+ </taglist>
+ <p>
+ Own Id: OTP-11888</p>
+ </item>
+ <item>
+ <p>
+ The systemd features of epmd have been removed from epmd
+ by default. To enable them you have to build erlang with
+ the configure option --enable-systemd.</p>
+ <p>
+ Own Id: OTP-11921</p>
+ </item>
+ <item>
+ <p>
+ Removed Erlang wrapper code used when calling
+ <c>binary_to_term/1</c>, and <c>binary_to_term/2</c>.
+ This improves the performance of these BIFs especially
+ when they are called with small binaries as input.</p>
+ <p>
+ Own Id: OTP-11931</p>
+ </item>
+ <item>
+ <p>
+ Add erlang:system_info(tolerant_timeofday), an API to
+ check whether compensation for sudden changes of system
+ time is enabled or not.</p>
+ <p>
+ Own Id: OTP-11970</p>
+ </item>
+ </list>
+ </section>
+
+</section>
+
+<section><title>Erts 6.0.1</title>
+
+ <section><title>Fixed Bugs and Malfunctions</title>
+ <list>
+ <item>
+ <p>
+ Fix broken system monitoring of <c>large_heap</c> for
+ non-smp VM. No message for <c>large_heap</c> was ever
+ sent on non-smp VM. Bug exist since R16B.</p>
+ <p>
+ Own Id: OTP-11852</p>
+ </item>
+ <item>
+ <p>
+ Fixed type spec of <c>erlang:system_info/1</c>.</p>
+ <p>
+ Own Id: OTP-11859 Aux Id: OTP-11615 </p>
+ </item>
+ </list>
+ </section>
+
+</section>
+
+<section><title>Erts 6.0</title>
+
+ <section><title>Fixed Bugs and Malfunctions</title>
+ <list>
+ <item>
+ <p>
+ The option dupnames did not work as intended in re. When
+ looking for names with {capture, [Name, ...]}, re:run
+ returned a random instance of the match for that name,
+ instead of the leftmost matching instance, which was what
+ the documentation stated. This is now corrected to adhere
+ to the documentation. The option {capture,all_names}
+ along with a re:inspect/2 function is also added to
+ further help in using named subpatterns.</p>
+ <p>
+ Own Id: OTP-11205</p>
+ </item>
+ <item>
+ <p>
+ Allow loading of NIF library with unicode path name</p>
+ <p>
+ Own Id: OTP-11408</p>
+ </item>
+ <item>
+ <p>
+ Allow loading of driver with unicode path name</p>
+ <p>
+ Own Id: OTP-11549</p>
+ </item>
+ <item>
+ <p>
+ Fixed a bug where starting Erlang without having an open
+ stdin on fd 0 would sometimes deadlock the emulator when
+ terminating.</p>
+ <p>
+ Own Id: OTP-11558</p>
+ </item>
+ <item>
+ <p>
+ The option '-names' in epmd now works on Windows (Thanks
+ to Johannes Weißl)</p>
+ <p>
+ Own Id: OTP-11565</p>
+ </item>
+ <item>
+ <p>
+ Correction of the examples in escript documentation.
+ (Thanks to Pierre Fenoll).</p>
+ <p>
+ Own Id: OTP-11577</p>
+ </item>
+ <item>
+ <p>
+ Fix bs_get_integer instruction</p>
+ <p>
+ The instruction bs_get_integer could unnecessarily
+ trigger a garbage collection in failure cases which is
+ unwanted or outright dangerous.</p>
+ <p>
+ Ex:</p>
+ <p>
+ &lt;&lt;X:Sz,_/bits&gt;&gt; = &lt;&lt;"some
+ binary"&gt;&gt;</p>
+ <p>
+ Previously, if Sz induced X to a bignum it would reserved
+ memory size this on the heap via a garbage collection
+ before checking if the size could actually match.</p>
+ <p>
+ It will now check the binary size before triggering a
+ collection.</p>
+ <p>
+ Own Id: OTP-11581</p>
+ </item>
+ <item>
+ <p>
+ Remove heap space overestimation in <c>binary_to_term</c>
+ (and remote message reception) for integers in the
+ intervals [-2147483648,-1] and [256,2147483647] on 64-bit
+ emulators.</p>
+ <p>
+ Own Id: OTP-11585</p>
+ </item>
+ <item>
+ <p>
+ Add support for detecting the separate tinfo library from
+ ncurses (Thanks to Dirkjan Ochtman)</p>
+ <p>
+ Own Id: OTP-11590</p>
+ </item>
+ <item>
+ <p>
+ Deprecation warning for system_flag(cpu_topology) has
+ been extended for removal in OTP 18 (Thanks to Steve
+ Vinoski for the update)</p>
+ <p>
+ Own Id: OTP-11602</p>
+ </item>
+ <item>
+ <p>
+ Documentation improvement regarding some awkward wording
+ around the +spp flag. (Thanks to Brian L. Troutwine )</p>
+ <p>
+ Own Id: OTP-11607</p>
+ </item>
+ <item>
+ <p>
+ Fixed bug where sendfile would return the wrong error
+ code for a remotely closed socket if the socket was in
+ passive mode. (Thanks to Vincent Siliakus for reporting
+ the bug.)</p>
+ <p>
+ Own Id: OTP-11614</p>
+ </item>
+ <item>
+ <p>
+ Increase garbage collection tenure rate</p>
+ <p>The garbage collector tries to maintain the previous
+ heap block size during a minor gc, i.e. 'need' is not
+ utilized in determining the size of the new heap, instead
+ it relies on tenure and garbage to be sufficiently
+ large.</p>
+ <p>In instances during intense growing with exclusively
+ live data on the heap coupled with delayed tenure,
+ fullsweeps would be triggered directly after a minor gc
+ to make room for 'need' since the new heap would be
+ full.</p>
+ <p>To remedy this, the tenure of terms on the minor heap
+ will always happen (if it is below the high watermark)
+ instead of every other minor gc.</p>
+ <p>Characteristics Impact: Reduced CPU-time spent in
+ garbage collection but may infer delays in collecting
+ garbage from the heap. Tweak 'fullsweep_after' options to
+ increase gc pressure if needed.</p>
+ <p>
+ Own Id: OTP-11617</p>
+ </item>
+ <item>
+ <p>
+ Fix bug when comparing integers with floats larger than
+ 2^992. The bug could potentially cause memory corruption
+ on 32-bit emulators.</p>
+ <p>
+ Own Id: OTP-11618</p>
+ </item>
+ <item>
+ <p>
+ Cross-compilation fixes for TileraMDE-3.0.1.125620</p>
+ <p>
+ Own Id: OTP-11635</p>
+ </item>
+ <item>
+ <p>
+ sendfile no longer uses async threads by default</p>
+ <p>
+ This has been done because a slow client attack is
+ possible if the async thread pool is used. The scenario
+ is:</p>
+ <p>
+ Client does a request for a file and then slowly receives
+ the file one byte at a time. This will eventually fill
+ the async thread pool with blocking sendfile operations
+ and thus starving the vm of all file operations.</p>
+ <p>
+ If you still want to use the async threads pool for
+ sendfile an option to enable it has been introduced.</p>
+ <p>
+ Thanks to Christopher Faulet for identifying this
+ vulnerability.</p>
+ <p>
+ *** POTENTIAL INCOMPATIBILITY ***</p>
+ <p>
+ Own Id: OTP-11639</p>
+ </item>
+ <item>
+ <p>
+ Do proper rollback of calls to
+ <c>enif_open_resource_type</c> when load/upgrade
+ callbacks of NIF library return failure.</p>
+ <p>
+ Own Id: OTP-11722</p>
+ </item>
+ <item>
+ <p>
+ Changed the default configuration when configuring with
+ <c>$ERL_TOP/configure</c> to be the same as when
+ configuring with <c>$ERL_TOP/otp_build configure</c>.</p>
+ <p>
+ Previously floating point exceptions got enabled by
+ default on Linux when HiPE was enabled when configuring
+ with <c>$ERL_TOP/configure</c>, but not when configuring
+ with <c>$ERL_TOP/otp_build configure</c>. The default is
+ now in both cases not to use floating point exceptions
+ since there still exist unresolved issues with floating
+ point exceptions on Linux.</p>
+ <p>
+ For more information see <seealso
+ marker="doc/installation_guide:INSTALL"><c>$ERL_TOP/HOWTO/INSTALL.md</c></seealso>.</p>
+ <p>
+ *** POTENTIAL INCOMPATIBILITY ***</p>
+ <p>
+ Own Id: OTP-11723</p>
+ </item>
+ <item>
+ <p>
+ A comment in erl_db_tree.c no longer differ from the
+ code. (Thanks to Cobus Carstens)</p>
+ <p>
+ Own Id: OTP-11793</p>
+ </item>
+ <item>
+ <p>
+ Fix epmd debug functionality for VxWorks (Thanks to Jay
+ True)</p>
+ <p>
+ Own Id: OTP-11808</p>
+ </item>
+ <item>
+ <p>
+ Use closefrom/2 when available in child_setup (Thanks to
+ Rick Reed and Anthony Ramine)</p>
+ <p>
+ Own Id: OTP-11809</p>
+ </item>
+ <item>
+ <p>
+ Fix dtrace/systemtap bug where the probe arguments would
+ be concatenated due to faulty length calculation. </p>
+ <p>
+ Thanks to Michal Ptaszek and Scott Lystig Fritchie</p>
+ <p>
+ Own Id: OTP-11816</p>
+ </item>
+ <item>
+ <p>
+ It is now better documented that the <c>+fn*</c> flags to
+ <c>erl</c> also affect how command line parameters and
+ environment variables are read. (Thanks to Vlad
+ Dumitrescu)</p>
+ <p>
+ Own Id: OTP-11818</p>
+ </item>
+ </list>
+ </section>
+
+
+ <section><title>Improvements and New Features</title>
+ <list>
+ <item>
+ <p>
+ Options to set match_limit and match_limit_recursion are
+ added to re:run. The option report_errors is also added
+ to get more information when re:run fails due to limits
+ or compilation errors.</p>
+ <p>
+ Own Id: OTP-10285</p>
+ </item>
+ <item>
+ <p> Dialyzer's <c>unmatched_return</c> warnings have been
+ corrected. </p>
+ <p>
+ Own Id: OTP-10908</p>
+ </item>
+ <item>
+ <p>
+ A common case is to wrap an argument to
+ <c>list_to_binary/1</c> in a list to ensure conversion
+ can happen even though the argument may already be a
+ binary. Take special care of this case and do not copy
+ binary.</p>
+ <p>
+ Impact: May cause incompatibility since a single binary
+ is no longer copied. Use <c>binary:copy/1,2</c> instead.</p>
+ <p>
+ *** POTENTIAL INCOMPATIBILITY ***</p>
+ <p>
+ Own Id: OTP-11082</p>
+ </item>
+ <item>
+ <p>
+ Make erlang:open_port/2 spawn and spawn_executable handle
+ unicode.</p>
+ <p>
+ Own Id: OTP-11105</p>
+ </item>
+ <item>
+ <p>
+ Handle unicode (widestring) in erl, erlc, heart, etc on
+ windows.</p>
+ <p>
+ Own Id: OTP-11135</p>
+ </item>
+ <item>
+ <p>
+ The version of the PCRE library Used by Erlang's re
+ module is raised to 8.33 from 7.6. This means, among
+ other things, better Unicode and Unicode Character
+ Properties support. New options connected to PCRE 8.33
+ are also added to the re module (ucd, notempty_atstart,
+ no_start_optimize). PCRE has extended the regular
+ expression syntax between 7.6 and 8.33, why this imposes
+ a potential incompatibility. Only very complicated
+ regular expressions may be affected, but if you know you
+ are using obscure features, please test run your regular
+ expressions and verify that their behavior has not
+ changed.</p>
+ <p>
+ *** POTENTIAL INCOMPATIBILITY ***</p>
+ <p>
+ Own Id: OTP-11204</p>
+ </item>
+ <item>
+ <p>Filenames containing UTF-8 encoded characters can now
+ be handled by erlc.</p>
+ <p>If you have set the <c>ERLC_EMULATOR</c> environment
+ variable, note that <c>erlc</c> in OTP 17 will only work
+ with <c>erl</c> in OTP 17 since the protocol between the
+ <c>erlc</c> program and the <c>erl_compile</c> module has
+ changed.</p>
+ <p>
+ Own Id: OTP-11248</p>
+ </item>
+ <item>
+ <p>
+ By giving --enable-static-{nifs,drivers} to configure it
+ is now possible to statically linking of nifs and drivers
+ to the main Erlang VM binary. At the moment only the asn1
+ and crypto nifs of the Erlang/OTP nifs and drivers have
+ been prepared to be statically linked. For more details
+ see the Installation Guide in the System documentation.</p>
+ <p>
+ Own Id: OTP-11258</p>
+ </item>
+ <item>
+ <p>
+ Erlang/OTP has been ported to the realtime operating
+ system OSE. The port supports both smp and non-smp
+ emulator. For details around the port and how to started
+ see the User's Guide in the <seealso
+ marker="ose:ose_intro">ose</seealso> application. </p>
+ <p>
+ Note that not all parts of Erlang/OTP has been ported. </p>
+ <p>
+ Notable things that work are: non-smp and smp emulators,
+ OSE signal interaction, crypto, asn1, run_erl/to_erl,
+ tcp, epmd, distribution and most if not all non-os
+ specific functionality of Erlang.</p>
+ <p>
+ Notable things that does not work are: udp/sctp, os_mon,
+ erl_interface, binding of schedulers.</p>
+ <p>
+ Own Id: OTP-11334</p>
+ </item>
+ <item>
+ <p>
+ Add the {active,N} socket option for TCP, UDP, and SCTP,
+ where N is an integer in the range -32768..32767, to
+ allow a caller to specify the number of data messages to
+ be delivered to the controlling process. Once the
+ socket's delivered message count either reaches 0 or is
+ explicitly set to 0 with inet:setopts/2 or by including
+ {active,0} as an option when the socket is created, the
+ socket transitions to passive ({active, false}) mode and
+ the socket's controlling process receives a message to
+ inform it of the transition. TCP sockets receive
+ {tcp_passive,Socket}, UDP sockets receive
+ {udp_passive,Socket} and SCTP sockets receive
+ {sctp_passive,Socket}. </p>
+ <p>
+ The socket's delivered message counter defaults to 0, but
+ it can be set using {active,N} via any gen_tcp, gen_udp,
+ or gen_sctp function that takes socket options as
+ arguments, or via inet:setopts/2. New N values are added
+ to the socket's current counter value, and negative
+ numbers can be used to reduce the counter value.
+ Specifying a number that would cause the socket's counter
+ value to go above 32767 causes an einval error. If a
+ negative number is specified such that the counter value
+ would become negative, the socket's counter value is set
+ to 0 and the socket transitions to passive mode. If the
+ counter value is already 0 and inet:setopts(Socket,
+ [{active,0}]) is specified, the counter value remains at
+ 0 but the appropriate passive mode transition message is
+ generated for the socket.</p>
+ <p>
+ Thanks to Steve Vinoski</p>
+ <p>
+ Own Id: OTP-11368</p>
+ </item>
+ <item>
+ <p>
+ A new optional scheduler utilization balancing mechanism
+ has been introduced. For more information see the
+ <seealso marker="erl#+sub"><c>+sub</c></seealso> command
+ line argument.</p>
+ <p>
+ Characteristics impact: None, when not enabled. When
+ enabled, changed timing in the system, normally a small
+ overhead due to measuring of utilization and calculating
+ balancing information. On some systems, such as old
+ Windows systems, the overhead can be quite substantial.
+ This time measurement overhead highly depend on the
+ underlying primitives provided by the OS.</p>
+ <p>
+ Own Id: OTP-11385</p>
+ </item>
+ <item>
+ <p>
+ A call to either the <c>garbage_collect/1</c> BIF or the
+ <c>check_process_code/2</c> BIF may trigger garbage
+ collection of another processes than the process calling
+ the BIF. The previous implementations performed these
+ kinds of garbage collections without considering the
+ internal state of the process being garbage collected. In
+ order to be able to more easily and more efficiently
+ implement yielding native code, these types of garbage
+ collections have been rewritten. A garbage collection
+ like this is now triggered by an asynchronous request
+ signal, the actual garbage collection is performed by the
+ process being garbage collected itself, and finalized by
+ a reply signal to the process issuing the request. Using
+ this approach processes can disable garbage collection
+ and yield without having to set up the heap in a state
+ that can be garbage collected.</p>
+ <p>
+ The <seealso
+ marker="erts:erlang#garbage_collect/2"><c>garbage_collect/2</c></seealso>,
+ and <seealso
+ marker="erts:erlang#check_process_code/3"><c>check_process_code/3</c></seealso>
+ BIFs have been introduced. Both taking an option list as
+ last argument. Using these, one can issue asynchronous
+ requests.</p>
+ <p>
+ <c>code:purge/1</c> and <c>code:soft_purge/1</c> have
+ been rewritten to utilize asynchronous
+ <c>check_process_code</c> requests in order to
+ parallelize work.</p>
+ <p>
+ Characteristics impact: A call to the
+ <c>garbage_collect/1</c> BIF or the
+ <c>check_process_code/2</c> BIF will normally take longer
+ time to complete while the system as a whole wont be as
+ much negatively effected by the operation as before. A
+ call to <c>code:purge/1</c> and <c>code:soft_purge/1</c>
+ may complete faster or slower depending on the state of
+ the system while the system as a whole wont be as much
+ negatively effected by the operation as before.</p>
+ <p>
+ Own Id: OTP-11388 Aux Id: OTP-11535, OTP-11648 </p>
+ </item>
+ <item>
+ <p>
+ Cleanup 'Buckets' and 'Time left' fields in crashdump to
+ ease parsing.</p>
+ <p>
+ Own Id: OTP-11419</p>
+ </item>
+ <item>
+ <p>
+ Add sync option to file:open/2.</p>
+ <p>
+ The sync option adds the POSIX O_SYNC flag to the open
+ system call on platforms that support the flag or its
+ equivalent, e.g., FILE_FLAG_WRITE_THROUGH on Windows. For
+ platforms that don't support it, file:open/2 returns
+ {error, enotsup} if the sync option is passed in. Thank
+ to Steve Vinoski and Joseph Blomstedt</p>
+ <p>
+ Own Id: OTP-11498</p>
+ </item>
+ <item>
+ <p>
+ erlang:binary_to_term will now cost an appropriate amount
+ of reductions and will interrupt (yield) for reschedule
+ if the term is big. This avoids too long schedules when
+ binary_to_term is used. (Thanks to Svante Karlsson for
+ the original patch)</p>
+ <p>
+ Impact: Programs running binary_to_term on large binaries
+ will run more smoothly, but rescheduling will impact the
+ single process performance of the BIF. Single threaded
+ benchmarks might show degraded performance of the BIF,
+ while general system behaviour will be improved.</p>
+ <p>
+ Own Id: OTP-11535 Aux Id: OTP-11388 </p>
+ </item>
+ <item>
+ <p>
+ Added high resolution icon for windows. (Thanks to Daniel
+ Goertz for the inspiration.)</p>
+ <p>
+ Own Id: OTP-11560</p>
+ </item>
+ <item>
+ <p>
+ Migration of memory carriers has been enabled by default
+ on all ERTS internal memory allocators based on the
+ <seealso
+ marker="erts_alloc#alloc_util"><c>alloc_util</c></seealso>
+ framework except for <c>temp_alloc</c>. That is, <seealso
+ marker="erts_alloc#M_acul"><c>+M&lt;S&gt;acul
+ de</c></seealso> is default for these allocators. Note
+ that this also implies changed allocation strategies for
+ all of these allocators. They will all now use the
+ "address order first fit carrier best fit" strategy.</p>
+ <p>
+ By passing <c>+Muacul 0</c> on the command line, all
+ configuration changes made by this change will be
+ reverted.</p>
+ <p>
+ Characteristics impact: Improved memory characteristics
+ with a smaller memory footprint at the expense of a quite
+ small performance cost.</p>
+ <p>
+ Own Id: OTP-11604 Aux Id: OTP-10279 </p>
+ </item>
+ <item>
+ <p>A clarification has been added to the documentation of
+ <c>-on_load()</c> in the Reference Manual that it is only
+ recommended for loading NIF libraries.</p>
+ <p>
+ Own Id: OTP-11611</p>
+ </item>
+ <item>
+ <p><c>+fnaw</c> is now default when starting the
+ emulator; it used to be <c>+fnl</c>.</p>
+ <p>
+ *** POTENTIAL INCOMPATIBILITY ***</p>
+ <p>
+ Own Id: OTP-11612</p>
+ </item>
+ <item>
+ <p>
+ EEP43: New data type - Maps</p>
+ <p>
+ With Maps you may for instance: <taglist> <item><c>M0 =
+ #{ a =&gt; 1, b =&gt; 2}, % create
+ associations</c></item> <item><c>M1 = M0#{ a := 10 }, %
+ update values</c></item> <item><c>M2 = M1#{ "hi" =&gt;
+ "hello"}, % add new associations</c></item> <item><c>#{
+ "hi" := V1, a := V2, b := V3} = M2. % match keys with
+ values</c></item> </taglist></p>
+ <p>
+ For information on how to use Maps please see Map Expressions in the
+ <seealso marker="doc/reference_manual:expressions#map_expressions">
+ Reference Manual</seealso>.</p>
+ <p>
+ The current implementation is without the following
+ features: <taglist> <item>No variable keys</item>
+ <item>No single value access</item> <item>No map
+ comprehensions</item> </taglist></p>
+ <p>
+ Note that Maps is <em>experimental</em> during OTP 17.0.</p>
+ <p>
+ Own Id: OTP-11616</p>
+ </item>
+ <item>
+ <p>
+ The previously deprecated driver API function
+ <c>driver_async_cancel()</c> has been removed. Due to
+ this, the driver API version has been bumped to 3.0.</p>
+ <p>
+ Thanks to Steve Vinoski.</p>
+ <p>
+ *** POTENTIAL INCOMPATIBILITY ***</p>
+ <p>
+ Own Id: OTP-11628</p>
+ </item>
+ <item>
+ <p>
+ Experimental "dirty scheduler" functionality has been
+ introduced. In order to try the functionality out, you
+ need to pass the command line argument
+ <c>--enable-dirty-schedulers</c> to <c>configure</c> when
+ building the system.</p>
+ <p>
+ Dirty schedulers can currently only be used by NIFs on a
+ system with SMP support. More information can be found in
+ the <seealso
+ marker="erl_nif#dirty_nifs"><c>erl_nif(3)</c></seealso>
+ documentation, the <seealso
+ marker="erl"><c>erl(1)</c></seealso> documentation, and
+ in the git commit comment of commit
+ 'c1c03ae4ee50e58b7669ea88ec4d29c6b2b67c7b'.</p>
+ <p>
+ Note that the functionality is <em>experimental</em>, and
+ <em>not supported</em>. This functionality <em>will</em>
+ be subject to backward incompatible changes. You should
+ <em>not</em> enable the dirty scheduler functionality on
+ production systems. It is only provided for testing.</p>
+ <p>
+ Thanks to Steve Vinoski.</p>
+ <p>
+ Own Id: OTP-11629</p>
+ </item>
+ <item>
+ <p>
+ Improve reduction cost and yielding of
+ <c>term_to_binary</c>. The reduction cost is increased
+ and garbage collection is disabled during yield.</p>
+ <p>
+ Impact: Improves system responsiveness when
+ <c>term_to_binary</c> is called with large terms without
+ significant degradation of single threaded performance.</p>
+ <p>
+ Own Id: OTP-11648 Aux Id: OTP-11388 </p>
+ </item>
+ <item>
+ <p>
+ By default, the system's version of zlib will be used,
+ provided its version is 1.2.4 or higher; otherwise the
+ built-in zlib will be used. The built-in version of zlib
+ has been bumped to 1.2.8. (Use the
+ <c>--enable-builtin-zlib</c> option to <c>configure</c>
+ to force the use of the built-in zlib.)</p>
+ <p>
+ Own Id: OTP-11669</p>
+ </item>
+ <item>
+ <p>
+ The default float encoding in binary_to_term and
+ external_size has been changed to use minor_mode 1
+ instead of 0.</p>
+ <p>
+ *** POTENTIAL INCOMPATIBILITY ***</p>
+ <p>
+ Own Id: OTP-11738</p>
+ </item>
+ <item>
+ <p>
+ Introduced the <c>configure</c> option
+ <c>--with-assumed-cache-line-size=SIZE</c>. For more
+ information see <seealso
+ marker="doc/installation_guide:INSTALL"><c>$ERL_TOP/HOWTO/INSTALL.md</c></seealso>.</p>
+ <p>
+ Own Id: OTP-11742</p>
+ </item>
+ <item>
+ <p>
+ Halfword emulator is marked as deprecated. It still works
+ as before but is planned to be removed in a future major
+ release.</p>
+ <p>
+ Own Id: OTP-11777</p>
+ </item>
+ <item>
+ <p>
+ The external format for Maps has changed in a way that is
+ not compatible with the format used in OTP 17.0-rc1 and
+ OTP 17.0-rc2.</p>
+ <p>
+ *** POTENTIAL INCOMPATIBILITY ***</p>
+ <p>
+ Own Id: OTP-11782</p>
+ </item>
+ <item>
+ <p>
+ Fixed faulty make dependency that would make some make
+ versions fail while building gen_git_version.mk.</p>
+ <p>
+ Own Id: OTP-11784</p>
+ </item>
+ <item>
+ <p>
+ Introduced functionality for allowing old drivers and NIF
+ libraries to be loaded during a transition period. For
+ more information see <seealso
+ marker="erts:erl_driver#version_management">the version
+ management section in the <c>erl_driver(3)</c>
+ documentation</seealso> and <seealso
+ marker="erts:erl_nif#version_management">the version
+ management section in the <c>erl_nif(3)</c>
+ documentation</seealso>.</p>
+ <p>
+ Own Id: OTP-11799</p>
+ </item>
+ <item>
+ <p>
+ Support file paths longer than 259 characters on Windows.
+ Long absolute paths are automatically converted to UNC
+ format with a <c>\\?\</c> prefix which is the only way to
+ represent long paths. The 259 character limit still
+ applies for individual file names, relative paths and the
+ current working directory.</p>
+ <p>
+ Own Id: OTP-11813</p>
+ </item>
+ <item>
+ <p>
+ Document that escript:create/2 also accepts a 3-elements
+ tuple containing files and zip:create/3 options to build
+ a zip file.</p>
+ <p>
+ Thanks to Pierre Fenoll</p>
+ <p>
+ Own Id: OTP-11827</p>
+ </item>
+ <item>
+ <p>
+ Add systemd socket activation for epmd.</p>
+ <p>
+ Thanks to Matwey V. Kornilov</p>
+ <p>
+ Own Id: OTP-11829</p>
<section><title>Erts 5.10.4.1</title>
<section><title>Known Bugs and Problems</title>
@@ -278,7 +1188,7 @@
processes before the BIF returns, or fail with an
exception due to the port not being open. </p><p> The
synchronous port BIFs are: </p> <list> <item><seealso
- marker="erlang#port_close/1/"><c>port_close/1</c></seealso></item>
+ marker="erlang#port_close/1"><c>port_close/1</c></seealso></item>
<item><seealso
marker="erlang#port_command/2"><c>port_command/2</c></seealso></item>
<item><seealso
@@ -4143,7 +5053,7 @@
<item>
<p>
The <c>configure</c> command line argument <seealso
- marker="doc/installation_guide:INSTALL#How-to-Build-and-Install-ErlangOTP_A-Closer-Look-at-the-individual-Steps_Configuring">--enable-ethread-pre-pentium4-compatibility</seealso>
+ marker="doc/installation_guide:INSTALL#Advanced-configuration-and-build-of-ErlangOTP">--enable-ethread-pre-pentium4-compatibility</seealso>
had no effect. This option is now also automatically
enabled if required on the build machine.</p>
<p>
@@ -4722,7 +5632,7 @@
platforms than before. If <c>configure</c> warns about no
atomic implementation available, try using the
<c>libatomic_ops</c> library. Use the <seealso
- marker="doc/installation_guide:INSTALL#How-to-Build-and-Install-ErlangOTP_A-Closer-Look-at-the-individual-Steps_Configuring">--with-libatomic_ops=PATH</seealso>
+ marker="doc/installation_guide:INSTALL#Advanced-configuration-and-build-of-ErlangOTP">--with-libatomic_ops=PATH</seealso>
<c>configure</c> command line argument when specifying
where the <c>libatomic_ops</c> installation is located.
The <c>libatomic_ops</c> library can be downloaded from:
@@ -4740,7 +5650,7 @@
the pentium 4 processor. If you want the runtime system
to be compatible with older processors (back to 486) you
need to pass the <seealso
- marker="doc/installation_guide:INSTALL#How-to-Build-and-Install-ErlangOTP_A-Closer-Look-at-the-individual-Steps_Configuring">--enable-ethread-pre-pentium4-compatibility</seealso>
+ marker="doc/installation_guide:INSTALL#Advanced-configuration-and-build-of-ErlangOTP">--enable-ethread-pre-pentium4-compatibility</seealso>
<c>configure</c> command line argument when configuring
the system.</p>
<p>