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diff --git a/erts/doc/src/notes.xml b/erts/doc/src/notes.xml
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--- a/erts/doc/src/notes.xml
+++ b/erts/doc/src/notes.xml
@@ -4,7 +4,7 @@
<chapter>
<header>
<copyright>
- <year>2004</year><year>2016</year>
+ <year>2004</year><year>2018</year>
<holder>Ericsson AB. All Rights Reserved.</holder>
</copyright>
<legalnotice>
@@ -31,6 +31,3903 @@
</header>
<p>This document describes the changes made to the ERTS application.</p>
+<section><title>Erts 10.2</title>
+
+ <section><title>Fixed Bugs and Malfunctions</title>
+ <list>
+ <item>
+ <p>
+ When a process was waiting for a TCP socket send
+ operation to complete, and another process closed the
+ socket during that send, the sending process could hang.
+ This bug has now been corrected.</p>
+ <p>
+ Own Id: OTP-12242 Aux Id: ERL-561 </p>
+ </item>
+ <item>
+ <p>
+ Document <c>bit_size</c> in match specifications and
+ allow it in <c>ets:fun2ms</c>.</p>
+ <p>
+ Own Id: OTP-15343 Aux Id: PR-1962 </p>
+ </item>
+ <item>
+ <p>
+ Fixed bug in <c>ets:select_replace</c> when called with a
+ fully bound key could cause a following call to
+ <c>ets:next</c> or <c>ets:prev</c> to crash the emulator
+ or return invalid result.</p>
+ <p>
+ Own Id: OTP-15346</p>
+ </item>
+ <item>
+ <p>When a module has been purged from memory, any
+ literals belonging to that module will be copied to all
+ processes that hold references to them. The max heap size
+ limit would be ignored in the garbage collection
+ initiated when copying literals to a process. If the max
+ heap size was exceeded, the process would typically be
+ terminated in the following garbage collection. Corrected
+ to terminate the process directly if copying a literal
+ would exceed the max heap size.</p>
+ <p>
+ Own Id: OTP-15360</p>
+ </item>
+ <item>
+ <p>
+ Fix compilation of run_erl on Solaris 11.4 and later.</p>
+ <p>
+ Own Id: OTP-15389</p>
+ </item>
+ <item>
+ <p>Fixed a bug where <c>lists:reverse/1-2</c> could use
+ far too many reductions. This bug was introduced in
+ <c>OTP 21.1</c>.</p>
+ <p>
+ Own Id: OTP-15436</p>
+ </item>
+ <item>
+ <p>Fixed a bug where a dirty scheduler could stay awake
+ forever if a distribution entry was removed as part of a
+ dirty GC.</p>
+ <p>
+ Own Id: OTP-15446 Aux Id: PR-2024 </p>
+ </item>
+ <item>
+ <p>
+ Fix microstate accounting handing in various places. Most
+ importantly the GC states when the GC is run on a dirty
+ scheduler are now managed correctly.</p>
+ <p>
+ Own Id: OTP-15450 Aux Id: ERIERL-229 </p>
+ </item>
+ <item>
+ <p>
+ Fixed bug in <c>file:sendfile</c> when the send operation
+ failed. For sockets in <c>active</c> modes it could cause
+ emulator crash or a hanging call. For sockets with
+ <c>{active,false}</c> an unexpected <c>{inet_reply, _,
+ _}</c> message could be sent to the calling process. The
+ bug exists since OTP-21.0.</p>
+ <p>
+ Own Id: OTP-15461 Aux Id: ERL-784 </p>
+ </item>
+ <item>
+ <p>
+ The erts configure script has been updated to reject any
+ CFLAGS that does not have <c>-O</c>. This in order to
+ prevent the common mistake of forgetting to add
+ <c>-O2</c> to custom CFLAGS.</p>
+ <p>
+ Own Id: OTP-15465</p>
+ </item>
+ <item>
+ <p>
+ Fix reduction count in lists:member/2</p>
+ <p>
+ Own Id: OTP-15474 Aux Id: ERIERL-229 </p>
+ </item>
+ </list>
+ </section>
+
+
+ <section><title>Improvements and New Features</title>
+ <list>
+ <item>
+ <p>
+ New <c>counters</c> and <c>atomics</c> modules supplies
+ access to highly efficient operations on mutable fixed
+ word sized variables.</p>
+ <p>
+ Own Id: OTP-13468</p>
+ </item>
+ <item>
+ <p>There is a new module <c>persistent_term</c> that
+ implements a term storage suitable for terms that are
+ frequently used but never or infrequently updated.
+ Lookups are done in constant time without copying the
+ terms.</p>
+ <p>
+ Own Id: OTP-14669 Aux Id: PR-1989 </p>
+ </item>
+ <item>
+ <p>
+ A function <c>inet:getifaddrs/1</c> that takes a list
+ with a namespace option has been added, for platforms
+ that support that feature, for example Linux (only?).</p>
+ <p>
+ Own Id: OTP-15121 Aux Id: ERIERL-189, PR-1974 </p>
+ </item>
+ <item>
+ <p>Added the <c>nopush</c> option for TCP sockets, which
+ corresponds to <c>TCP_NOPUSH</c> on *BSD and
+ <c>TCP_CORK</c> on Linux.</p>
+ <p>This is also used internally in <c>file:sendfile</c>
+ to reduce latency on subsequent send operations.</p>
+ <p>
+ Own Id: OTP-15357 Aux Id: ERL-698 </p>
+ </item>
+ <item>
+ <p>List subtraction (The <c>--</c> operator) will now
+ yield properly on large inputs.</p>
+ <p>
+ Own Id: OTP-15371</p>
+ </item>
+ <item>
+ <p>
+ Optimize handling of send_delay for tcp sockes to better
+ work with the new pollthread implementation introduced in
+ OTP-21.</p>
+ <p>
+ Own Id: OTP-15471 Aux Id: ERIERL-229 </p>
+ </item>
+ <item>
+ <p>
+ Optimize driver_set_timer with a zero timeout to
+ short-circuit and not create any timer structure, but
+ instead schedule the timer immediately.</p>
+ <p>
+ Own Id: OTP-15472 Aux Id: ERIERL-229 </p>
+ </item>
+ <item>
+ <p>
+ Add <c>erl_xcomp_code_model_small</c> as a cross
+ configure variable in order to let the emulator be build
+ with the assumption that a small code model will be used
+ on the target machine.</p>
+ <p>
+ Own Id: OTP-15473 Aux Id: ERIERL-229 </p>
+ </item>
+ <item>
+ <p>
+ Add a new pollset that is made to handle sockets that use
+ <c>{active, true}</c> or <c>{active, N}</c>. The new
+ pollset will not be polled by a pollthread, but instead
+ polled by a normal scheduler.</p>
+ <p>
+ This change was made because of the overhead associated
+ with constantly having to re-apply the ONESHOT mechanism
+ on fds that all input events were interesting.</p>
+ <p>
+ The new pollset is only active on platforms that support
+ concurrent kernel poll updates, i.e. Linux and BSD.</p>
+ <p>
+ Own Id: OTP-15475 Aux Id: ERIERL-229 </p>
+ </item>
+ <item>
+ <p>
+ Fix bug where emulator would segfault if a literal
+ message was sent when sequence tracing was enabled.</p>
+ <p>
+ Own Id: OTP-15478 Aux Id: ERL-741 </p>
+ </item>
+ </list>
+ </section>
+
+</section>
+
+<section><title>Erts 10.1.3</title>
+
+ <section><title>Improvements and New Features</title>
+ <list>
+ <item>
+ <p>Added an optional <c>./configure</c> flag to compile
+ the emulator with spectre mitigation:
+ <c>--with-spectre-mitigation</c></p>
+ <p>Note that this requires a recent version of GCC with
+ support for spectre mitigation and the
+ <c>--mindirect-branch=thunk</c> flag, such as
+ <c>8.1</c>.</p>
+ <p>
+ Own Id: OTP-15430 Aux Id: ERIERL-237 </p>
+ </item>
+ </list>
+ </section>
+
+</section>
+
+<section><title>Erts 10.1.2</title>
+
+ <section><title>Fixed Bugs and Malfunctions</title>
+ <list>
+ <item>
+ <p>Fixed a rare bug where files could be closed on a
+ normal instead of an IO scheduler, resulting in system
+ instability if the operation blocked.</p>
+ <p>
+ Own Id: OTP-15421</p>
+ </item>
+ </list>
+ </section>
+
+</section>
+
+<section><title>Erts 10.1.1</title>
+
+ <section><title>Fixed Bugs and Malfunctions</title>
+ <list>
+ <item>
+ <p>
+ A bug where the socket option 'pktoptions' caused a read
+ of uninitialized memory has been fixed. Would cause
+ malfunction on FreeBSD.</p>
+ <p>
+ Own Id: OTP-14297 Aux Id: OTP-15141 </p>
+ </item>
+ <item>
+ <p>Fixed a memory leak on errors when reading files.</p>
+ <p>
+ Own Id: OTP-15318</p>
+ </item>
+ <item>
+ <p>File access through UNC paths works again on Windows.
+ This regression was introduced in OTP 21.</p>
+ <p>
+ Own Id: OTP-15333 Aux Id: ERL-737 </p>
+ </item>
+ </list>
+ </section>
+
+</section>
+
+<section><title>Erts 10.1</title>
+
+ <section><title>Fixed Bugs and Malfunctions</title>
+ <list>
+ <item>
+ <p>
+ Fix the seq_trace token to not be cleared when a process
+ receives messages sent by erts. Some examples of when
+ this could happen is all port BIFs, i.e.
+ <c>open_port</c>, <c>port_command</c> etc etc.</p>
+ <p>
+ Fix so that messages sent by nifs can be traced using
+ normal and <c>seq_trace</c> tracing.</p>
+ <p>
+ Own Id: OTP-15038 Aux Id: ERL-602 </p>
+ </item>
+ <item>
+ <p>
+ Fixed specs and documentation for <c>process_info</c>
+ item <c>monitored_by</c> to include port identifiers and
+ nif resources as possible types.</p>
+ <p>
+ Own Id: OTP-15180 Aux Id: ERL-648 </p>
+ </item>
+ <item>
+ <p>
+ Fix bug in generation of erl_crash.dump, which could
+ cause VM to crash.</p>
+ <p>
+ Bug exist since erts-9.2 (OTP-20.2).</p>
+ <p>
+ Own Id: OTP-15181</p>
+ </item>
+ <item>
+ <p>
+ Fix bug where ctrl-break or ctrl-c would not trigger the
+ break mode properly on Windows. This bug was introduced
+ in erts-10.0 (OTP-21).</p>
+ <p>
+ Own Id: OTP-15205</p>
+ </item>
+ <item>
+ <p>
+ Fix a performance bug for reception of UDP packages,
+ where a memory buffer would be reallocated when it should
+ not have been.</p>
+ <p>
+ Introduce a limit on the maximum automatic increase of
+ the UDP user-space buffer to the theoretical max of the
+ network PATH, i.e. 65535.</p>
+ <p>
+ Own Id: OTP-15206</p>
+ </item>
+ <item>
+ <p>
+ Fix alignment of erts allocator state internally in erts.
+ With the improper alignment the emulator would refuse to
+ start when compiled with clang on 32-bit systems.</p>
+ <p>
+ Own Id: OTP-15208 Aux Id: PR-1897 ERL-677 </p>
+ </item>
+ <item>
+ <p>
+ Fix bug where too many concurrent calls to
+ <c>erlang:open_port({spawn,"cmd"},...)</c> would result
+ in the emulator terminating with the reason "Failed to
+ write to erl_child_setup: ". After this fix the
+ <c>open_port</c> call will throw an <c>emfile</c>
+ exception instead.</p>
+ <p>
+ Own Id: OTP-15210</p>
+ </item>
+ <item>
+ <p>
+ Upgraded the ERTS internal PCRE library from version 8.41
+ to version 8.42. See <url
+ href="http://pcre.org/original/changelog.txt">http://pcre.org/original/changelog.txt</url>
+ for information about changes made to PCRE. This library
+ implements major parts of the <seealso
+ marker="stdlib:re"><c>re</c></seealso> regular
+ expressions module.</p>
+ <p>
+ Own Id: OTP-15217</p>
+ </item>
+ <item>
+ <p>
+ Fix <c>open_port({fd,X,Y}, ...)</c> to release the file
+ descriptors from the pollset when closing the port.
+ Without this fix the same file descriptor number could
+ not be reused when doing multiple open_port and
+ port_close sequences.</p>
+ <p>
+ Own Id: OTP-15236 Aux Id: ERL-692 </p>
+ </item>
+ <item>
+ <p>
+ Fixed bug in <c>float_to_list/2</c> and
+ <c>float_to_binary/2</c> with options
+ <c>[{decimals,0},compact]</c> causing totally wrong
+ results. Bug exists since OTP-21.0.</p>
+ <p>
+ Own Id: OTP-15276 Aux Id: PR-1920 </p>
+ </item>
+ <item>
+ <p>
+ Fixed bug in <c>erlang:memory</c> causing <c>ets</c> to
+ report too much. This small false memory leak (16 bytes
+ each time) can only happen when a specific race condition
+ occurs between scheduler threads on a table with option
+ <c>write_concurrency</c>.</p>
+ <p>
+ Own Id: OTP-15278</p>
+ </item>
+ <item>
+ <p>
+ Minor <c>configure</c> test fixes</p>
+ <p>
+ Own Id: OTP-15282</p>
+ </item>
+ <item>
+ <p>
+ Improved robustness of distribution connection setup. In
+ OTP-21.0 a truly asynchronous connection setup was
+ introduced. This is further improvement on that work to
+ make the emulator more robust and also be able to recover
+ in cases when involved Erlang processes misbehave.</p>
+ <p>
+ Own Id: OTP-15297 Aux Id: OTP-15279, OTP-15280 </p>
+ </item>
+ </list>
+ </section>
+
+
+ <section><title>Improvements and New Features</title>
+ <list>
+ <item>
+ <p>
+ The socket options <c>recvtos</c>, <c>recvttl</c>,
+ <c>recvtclass</c> and <c>pktoptions</c> have been
+ implemented in the socket modules. See the documentation
+ for the <c>gen_tcp</c>, <c>gen_udp</c> and <c>inet</c>
+ modules. Note that support for these in the runtime
+ system is platform dependent. Especially for
+ <c>pktoptions</c> which is very Linux specific and
+ obsoleted by the RFCs that defined it.</p>
+ <p>
+ Own Id: OTP-15145 Aux Id: ERIERL-187 </p>
+ </item>
+ </list>
+ </section>
+
+</section>
+
+<section><title>Erts 10.0.8</title>
+
+ <section><title>Fixed Bugs and Malfunctions</title>
+ <list>
+ <item>
+ <p>
+ As of ERTS version 10.0 (OTP 21.0) the
+ <c>erl_child_setup</c> program, which creates port
+ programs, ignores <c>TERM</c> signals. This setting was
+ unintentionally inherited by port programs. Handling of
+ <c>TERM</c> signals in port programs has now been
+ restored to the default behavior. That is, terminate the
+ process.</p>
+ <p>
+ Own Id: OTP-15289 Aux Id: ERIERL-235, OTP-14943, ERL-576 </p>
+ </item>
+ <item>
+ <p>
+ The fix made for OTP-15279 in erts-10.07 (OTP-21.0.8) was
+ not complete. It could cause a new connection attempt to
+ be incorrectly aborted in certain cases. This fix will
+ amend that flaw.</p>
+ <p>
+ Own Id: OTP-15296 Aux Id: OTP-15279, ERIERL-226 </p>
+ </item>
+ </list>
+ </section>
+
+</section>
+
+<section><title>Erts 10.0.7</title>
+
+ <section><title>Fixed Bugs and Malfunctions</title>
+ <list>
+ <item>
+ <p>
+ A process could get stuck in an infinite rescheduling
+ loop between normal and dirty schedulers. This bug was
+ introduced in ERTS version 10.0.</p>
+ <p>
+ Thanks to Maxim Fedorov for finding and fixing this
+ issue.</p>
+ <p>
+ Own Id: OTP-15275 Aux Id: PR-1943 </p>
+ </item>
+ <item>
+ <p>
+ Garbage collection of a distribution entry could cause an
+ emulator crash if <c>net_kernel</c> had not brought
+ previous connection attempts on it down properly.</p>
+ <p>
+ Own Id: OTP-15279 Aux Id: ERIERL-226 </p>
+ </item>
+ </list>
+ </section>
+
+</section>
+
+<section><title>Erts 10.0.6</title>
+
+ <section><title>Fixed Bugs and Malfunctions</title>
+ <list>
+ <item>
+ <p>
+ A race between termination of a process and resume of the
+ same process via <c>erlang:resume_process/1</c> could
+ cause the VM to crash. This bug was introduced in erts
+ version 10.0 (OTP 21.0).</p>
+ <p>
+ Own Id: OTP-15237</p>
+ </item>
+ <item>
+ <p>
+ When tracing on <c>running</c>, <c>in</c> trace events
+ could be lost when a process was rescheduled between a
+ dirty and a normal scheduler.</p>
+ <p>
+ Own Id: OTP-15269 Aux Id: ERL-713 </p>
+ </item>
+ </list>
+ </section>
+
+</section>
+
+<section><title>Erts 10.0.5</title>
+
+ <section><title>Fixed Bugs and Malfunctions</title>
+ <list>
+ <item>
+ <p>
+ Fixed a bug which caused an emulator crash when
+ <c>enif_send()</c> was called by a NIF that executed on a
+ dirty scheduler. The bug was either triggered when the
+ NIF called <c>enif_send()</c> without a message
+ environment, or when the process executing the NIF was
+ <c>send</c> traced.</p>
+ <p>
+ Own Id: OTP-15223</p>
+ </item>
+ <item>
+ <p>
+ Fixed a bug causing some Erlang references to be
+ inconsistently ordered. This could for example cause
+ failure to look up certain elements with references as
+ keys in search data structures. This bug was introduced
+ in R13B02.</p>
+ <p>
+ Thanks to Simon Cornish for finding the bug and supplying
+ a fix.</p>
+ <p>
+ *** POTENTIAL INCOMPATIBILITY ***</p>
+ <p>
+ Own Id: OTP-15225</p>
+ </item>
+ </list>
+ </section>
+
+</section>
+
+<section><title>Erts 10.0.4</title>
+
+ <section><title>Fixed Bugs and Malfunctions</title>
+ <list>
+ <item>
+ <p>Fixed a bug that prevented the <c>noshell</c> option
+ from working correctly on Mac OS X and BSD.</p>
+ <p>
+ Own Id: OTP-15169</p>
+ </item>
+ <item>
+ <p>Fixed a crash when matching directly against a literal
+ map using a single key that had been saved on the
+ stack.</p>
+ <p>
+ Own Id: OTP-15184</p>
+ </item>
+ <item>
+ <p>Fix node crash when passing a bad time option to
+ <c>file:read_file_info/2</c>.</p>
+ <p>
+ Own Id: OTP-15196</p>
+ </item>
+ </list>
+ </section>
+
+</section>
+
+<section><title>Erts 10.0.3</title>
+
+ <section><title>Fixed Bugs and Malfunctions</title>
+ <list>
+ <item>
+ <p>Fixed a scheduler bug that caused normal schedulers to
+ run dirty code.</p>
+ <p>
+ Own Id: OTP-15154</p>
+ </item>
+ <item>
+ <p>
+ Fixed a bug in <c>erlang:trace_info/2</c> which caused
+ the emulator to crash when a bad argument was passed. The
+ bug was introduced in ERTS version 10.0.</p>
+ <p>
+ Own Id: OTP-15183 Aux Id: ERL-670 </p>
+ </item>
+ </list>
+ </section>
+
+</section>
+
+<section><title>Erts 10.0.2</title>
+
+ <section><title>Fixed Bugs and Malfunctions</title>
+ <list>
+ <item>
+ <p>Fixed a rare bug that could cause processes to be
+ scheduled after they had been freed.</p>
+ <p>
+ Own Id: OTP-15067 Aux Id: ERL-573 </p>
+ </item>
+ <item>
+ <p>Fixed a race condition in the inet driver that could
+ cause receive to hang when the emulator was compiled with
+ gcc 8.</p>
+ <p>
+ Own Id: OTP-15158 Aux Id: ERL-654 </p>
+ </item>
+ </list>
+ </section>
+
+</section>
+
+<section><title>Erts 10.0.1</title>
+
+ <section><title>Fixed Bugs and Malfunctions</title>
+ <list>
+ <item>
+ <p>The keys used in <c>os:getenv</c> and <c>os:putenv</c>
+ are case-insensitive again on Windows.</p>
+ <p>
+ Own Id: OTP-15147 Aux Id: ERL-644 </p>
+ </item>
+ </list>
+ </section>
+
+</section>
+
+<section><title>Erts 10.0</title>
+
+ <section><title>Fixed Bugs and Malfunctions</title>
+ <list>
+ <item>
+ <p>
+ The type specifications for <c>file:posix/0</c> and
+ <c>inet:posix/0</c> have been updated according to which
+ errors file and socket operations should be able to
+ return.</p>
+ <p>
+ Own Id: OTP-14019 Aux Id: ERL-550 </p>
+ </item>
+ <item>
+ <p>
+ Fix error printout from run_erl and a bug that could
+ cause unintended fds to be leaked into the started
+ program.</p>
+ <p>
+ Own Id: OTP-14537 Aux Id: PR1529 </p>
+ </item>
+ <item>
+ <p> File operations used to accept <seealso
+ marker="kernel:file#type-name_all">filenames</seealso>
+ containing null characters (integer value zero). This
+ caused the name to be truncated and in some cases
+ arguments to primitive operations to be mixed up.
+ Filenames containing null characters inside the filename
+ are now <em>rejected</em> and will cause primitive file
+ operations to fail. </p> <p> Also environment variable
+ operations used to accept <seealso
+ marker="kernel:os#type-env_var_name">names</seealso> and
+ <seealso
+ marker="kernel:os#type-env_var_value">values</seealso> of
+ environment variables containing null characters (integer
+ value zero). This caused operations to silently produce
+ erroneous results. Environment variable names and values
+ containing null characters inside the name or value are
+ now <em>rejected</em> and will cause environment variable
+ operations to fail. </p> <p>Primitive environment
+ variable operations also used to accept the <c>$=</c>
+ character in environment variable names causing various
+ problems. <c>$=</c> characters in environment variable
+ names are now also <em>rejected</em>. </p> <p>Also
+ <seealso
+ marker="kernel:os#cmd/1"><c>os:cmd/1</c></seealso> now
+ reject null characters inside its <seealso
+ marker="kernel:os#type-os_command">command</seealso>.
+ </p> <p><seealso
+ marker="erts:erlang#open_port/2"><c>erlang:open_port/2</c></seealso>
+ will also reject null characters inside the port name
+ from now on.</p>
+ <p>
+ *** POTENTIAL INCOMPATIBILITY ***</p>
+ <p>
+ Own Id: OTP-14543 Aux Id: ERL-370 </p>
+ </item>
+ <item>
+ <p>
+ Fix bugs related to the bookkeeping of microstate
+ accounting states.</p>
+ <p>
+ Own Id: OTP-14652</p>
+ </item>
+ <item>
+ <p><c>os:putenv</c> and <c>os:getenv</c> no longer access
+ the process environment directly and instead work on a
+ thread-safe emulation. The only observable difference is
+ that it's <em>not</em> kept in sync with libc
+ <c>getenv(3)</c> / <c>putenv(3)</c>, so those who relied
+ on that behavior in drivers or NIFs will need to add
+ manual synchronization.</p> <p>On Windows this means that
+ you can no longer resolve DLL dependencies by modifying
+ the <c>PATH</c> just before loading the driver/NIF. To
+ make this less of a problem, the emulator now adds the
+ target DLL's folder to the DLL search path.</p>
+ <p>
+ *** POTENTIAL INCOMPATIBILITY ***</p>
+ <p>
+ Own Id: OTP-14666</p>
+ </item>
+ <item>
+ <p>Corrected <c>erlang:is_builtin(erlang, M, F)</c> to
+ return <c>true</c> for <c>apply/2</c> and
+ <c>yield/0</c>.</p>
+ <p>
+ Own Id: OTP-14713 Aux Id: ERL-500 </p>
+ </item>
+ <item>
+ <p>Fixed a bug where the PATH environment variable wasn't
+ updated correctly on a release downgrade, effectively
+ keeping the PATH of the new release.</p>
+ <p>
+ Own Id: OTP-14719</p>
+ </item>
+ <item>
+ <p>A receive optimization that avoids scanning the entire
+ message queue when receiving a message containing a
+ freshly created reference could in rare circumstances
+ (involving recursive calls to the functions that does the
+ receive) cause the receive to hang. This has been
+ corrected.</p>
+ <p>
+ Own Id: OTP-14782 Aux Id: ERL-511 </p>
+ </item>
+ <item>
+ <p>
+ Fix building of Erlang/OTP on platforms which have small
+ data area with short addressing. For example the
+ PowerPC/RTEMS platform.</p>
+ <p>
+ Own Id: OTP-14909 Aux Id: PR-1692 </p>
+ </item>
+ <item>
+ <p>Fixed a crash when <c>enif_make_binary</c> is called
+ with a binary produced by <c>enif_inspect_binary</c> in a
+ different environment.</p>
+ <p>
+ Own Id: OTP-14931</p>
+ </item>
+ <item>
+ <p>Fixed a crash when <c>enif_make_binary</c> is called
+ more than once with a binary that had previously been
+ added to an <c>enif_ioq</c>.</p>
+ <p>
+ Own Id: OTP-14932</p>
+ </item>
+ <item>
+ <p>
+ The erl_child_setup program now ignores SIGTERM signals.</p>
+ <p>
+ Own Id: OTP-14943 Aux Id: ERL-576 </p>
+ </item>
+ <item>
+ <p>
+ Force 64-bit alignment on pre-allocators on architectures
+ which needs it.</p>
+ <p>
+ Own Id: OTP-14977</p>
+ </item>
+ <item>
+ <p>
+ Fixed a bug where dirty scheduler picked up non-dirty
+ work.</p>
+ <p>
+ Own Id: OTP-14978</p>
+ </item>
+ <item>
+ <p>
+ Calls to <c>gen_tcp:send/2</c> on closed sockets now
+ returns <c>{error, closed}</c> instead of
+ <c>{error,enotconn}</c>.</p>
+ <p>
+ Own Id: OTP-15001</p>
+ </item>
+ <item>
+ <p>
+ <c>erlang:monotonic_time/1</c> failed with <c>badarg</c>
+ when passing the <c>perf_counter</c> time unit as
+ argument.</p>
+ <p>
+ Own Id: OTP-15008</p>
+ </item>
+ <item>
+ <p>
+ Fix bug where rapid <c>init:restart()</c> calls would
+ sometimes crash because a code load request leaked in
+ between the restarts.</p>
+ <p>
+ Own Id: OTP-15013</p>
+ </item>
+ <item>
+ <p>
+ Improve <c>float_to_list(F, [{decimals,D}])</c> to closer
+ conform with <c>io_lib:format("~.*f", [D,F])</c>.</p>
+ <p>
+ There are however, still cases when <c>float_to_list</c>
+ does not produce the exact same result as
+ <c>io_lib:format</c>, especially for large values
+ <c>F</c> and/or many decimals <c>D</c>.</p>
+ <p>
+ Own Id: OTP-15015 Aux Id: OTP-14890 </p>
+ </item>
+ <item>
+ <p>Fixed a deadlock that would occur on certain
+ allocators when a reallocation failed with <c>+ramv</c>
+ enabled.</p>
+ <p>
+ Own Id: OTP-15024</p>
+ </item>
+ <item>
+ <p>
+ Fix bug that made it impossible to use an erl_tracer as
+ the seq_trace trace receiver.</p>
+ <p>
+ Own Id: OTP-15029</p>
+ </item>
+ <item>
+ <p>
+ Fix bug where a large (> 1 GB) emulator generated error
+ logger message would cause the emulator to crash.</p>
+ <p>
+ Own Id: OTP-15032</p>
+ </item>
+ <item>
+ <p>The emulator will no longer crash when reading the
+ file information of an ordinary file that has an NTFS
+ reparse point, such as files stored in a OneDrive-mapped
+ folder.</p>
+ <p>
+ Own Id: OTP-15062 Aux Id: ERL-615 </p>
+ </item>
+ <item>
+ <p>
+ Fixed bug in <c>enif_binary_to_term</c> which could cause
+ memory corruption for immediate terms (atoms, small
+ integers, pids, ports, empty lists).</p>
+ <p>
+ Own Id: OTP-15080</p>
+ </item>
+ <item>
+ <p>
+ Fixed bug in <c>erlang:system_profile/2</c> that could
+ cause superfluous <c>{profile,_,active,_,_}</c> messages
+ for terminating processes.</p>
+ <p>
+ Own Id: OTP-15085</p>
+ </item>
+ <item>
+ <p>
+ On OSs with per thread CPU time support, change
+ <c>cpu_timestamp</c> in <seealso
+ marker="erlang#trace/3">erlang:trace/3</seealso> to use
+ it instead of per process CPU time. This makes this
+ option useable on such OSs when running multiple
+ schedulers.</p>
+ <p>
+ Own Id: OTP-15090</p>
+ </item>
+ <item>
+ <p>
+ Fix segfault in abort_signal_task which could happen if a
+ port terminated while there were outstanding port tasks
+ that were not signals, for example a
+ ready_input/ready_output event.</p>
+ <p>
+ Own Id: OTP-15108 Aux Id: ERL-621 </p>
+ </item>
+ <item>
+ <p>
+ Fixed bug in <c>ets</c> that could cause VM crash if
+ process A terminates after fixating a table and process B
+ deletes the table at "the same time". The table fixation
+ could be done with <c>ets:safe_fixtable</c> or if process
+ A terminates in the middle of a long running
+ <c>select</c> or <c>match</c> call.</p>
+ <p>
+ Own Id: OTP-15109</p>
+ </item>
+ <item>
+ <p>Owner and group changes through
+ <c>file:write_file_info</c>, <c>file:change_owner</c>,
+ and <c>file:change_group</c> will no longer report
+ success on permission errors.</p>
+ <p>
+ *** POTENTIAL INCOMPATIBILITY ***</p>
+ <p>
+ Own Id: OTP-15118</p>
+ </item>
+ <item>
+ <p>
+ Fix a bug error reporting from escripts on windows where
+ the error message would get garbled.</p>
+ <p>
+ Own Id: OTP-15119 Aux Id: PR-1826 </p>
+ </item>
+ <item>
+ <p>
+ Fix segfault when a process is interally re-scheduled
+ while being traced for in out events. This bug was
+ introduced in erts-8.0 (OTP-19.0).</p>
+ <p>
+ Own Id: OTP-15125</p>
+ </item>
+ </list>
+ </section>
+
+
+ <section><title>Improvements and New Features</title>
+ <list>
+ <item>
+ <p>It is now possible to open device files and FIFOs with
+ <c>file:open/2</c>.</p>
+ <p>
+ Own Id: OTP-11462</p>
+ </item>
+ <item>
+ <p>
+ The <c>erlang:system_flag(scheduler_wall_time,Bool)</c>
+ call is now reference counted and will be turned off if
+ the (last) process that started the performance
+ statistics dies. Thus it is no longer possible to start
+ the statistics with <c>rpc:call(Node, erlang,
+ system_flag, [scheduler_wall_time, true])</c> since it
+ will be turned off directly afterwards when the rpc
+ process dies.</p>
+ <p>
+ *** POTENTIAL INCOMPATIBILITY ***</p>
+ <p>
+ Own Id: OTP-11694</p>
+ </item>
+ <item>
+ <p>A new logging API is added to Erlang/OTP, see the
+ <seealso
+ marker="kernel:logger"><c>logger(3)</c></seealso> manual
+ page, and section <seealso
+ marker="kernel:logger_chapter">Logging</seealso> in the
+ Kernel User's Guide.</p>
+ <p>Calls to <c>error_logger</c> are automatically
+ redirected to the new API, and legacy error logger event
+ handlers can still be used. It is, however, recommended
+ to use the Logger API directly when writing new code.</p>
+ <p>Notice the following potential incompatibilities:</p>
+ <list> <item><p>Kernel configuration parameters
+ <c>error_logger</c> still works, but is overruled if the
+ default handler's output destination is configured with
+ Kernel configuration parameter <c>logger</c>.</p> <p>In
+ general, parameters for configuring error logger are
+ overwritten by new parameters for configuring
+ Logger.</p></item> <item><p>The concept of SASL error
+ logging is deprecated, meaning that by default the SASL
+ application does not affect which log events are
+ logged.</p> <p>By default, supervisor reports and crash
+ reports are logged by the default Logger handler started
+ by Kernel, and end up at the same destination (terminal
+ or file) as other standard log event from Erlang/OTP.</p>
+ <p>Progress reports are not logged by default, but can be
+ enabled by setting the primary log level to info, for
+ example with the Kernel configuration parameter
+ <c>logger_level</c>.</p> <p>To obtain backwards
+ compatibility with the SASL error logging functionality
+ from earlier releases, set Kernel configuration parameter
+ <c>logger_sasl_compatible</c> to <c>true</c>. This
+ prevents the default Logger handler from logging any
+ supervisor-, crash-, or progress reports. Instead, SASL
+ adds a separate Logger handler during application start,
+ which takes care of these log events. The SASL
+ configuration parameters <c>sasl_error_logger</c> and
+ <c>sasl_errlog_type</c> specify the destination (terminal
+ or file) and severity level to log for these
+ events.</p></item></list>
+ <p>
+ Since Logger is new in Erlang/OTP 21.0, we do reserve the
+ right to introduce changes to the Logger API and
+ functionality in patches following this release. These
+ changes might or might not be backwards compatible with
+ the initial version.</p>
+ <p>
+ *** POTENTIAL INCOMPATIBILITY ***</p>
+ <p>
+ Own Id: OTP-13295</p>
+ </item>
+ <item>
+ <p>
+ <c>gen_sctp:connect_init/4</c> or rather connect in
+ <c>inet_drv.c</c> for SCTP has been fixed to not check
+ the write file descriptor for writeability after a
+ connect, since for SCTP (SOCK_SEQPACKET) that property
+ does not seem to be any kind of indicator for when a
+ connect has finished. This fixes connects that the OS
+ returned as "in progress" that was misinterpreted by
+ <c>gen_sctp:connect_init</c> as failed.</p>
+ <p>
+ Own Id: OTP-13760 Aux Id: PR-1592 </p>
+ </item>
+ <item>
+ <p>The file driver has been rewritten as a NIF,
+ decreasing the latency of file operations. Notable
+ incompatibilities are:</p> <list> <item><p>The
+ <c>use_threads</c> option for <c>file:sendfile/5</c> no
+ longer has any effect; we either use non-blocking
+ <c>sendfile(2)</c> or fall back to <c>file:read</c> +
+ <c>gen_tcp:send</c>. </p></item> <item><p>The
+ file-specific DTrace probes have been removed. The same
+ effect can be achieved with normal tracing together with
+ the <c>nif__entry</c>/<c>nif__return</c> probes to track
+ scheduling.</p></item> </list>
+ <p>
+ *** POTENTIAL INCOMPATIBILITY ***</p>
+ <p>
+ Own Id: OTP-14256</p>
+ </item>
+ <item>
+ <p>The I/O polling functionality of erts has been
+ re-written to better make use of the OSs polling
+ mechanisms. This change means that erts will now always
+ prefer to use a kernel-polling mechanism if possible.
+ Also all of the I/O polling has been moved to dedicated
+ threads instead of being placed in the scheduler
+ loops.</p> <p>As a result of this, the <c>erl</c> options
+ <c>+K</c> and <c>+secio</c> have been removed. It is
+ still possible to disable kernel-poll, but it has to be
+ done at compile time through the configure option
+ <c>--disable-kernel-poll</c>.</p> <p>The new <c>erl</c>
+ options <seealso marker="erl#+IOt"><c>+IOt</c></seealso>
+ and <seealso marker="erl#+IOp"><c>+IOp</c></seealso> can
+ be used to change how many IO poll threads and poll sets
+ that erts should use. See their respective documentation
+ for more details.</p>
+ <p>
+ Own Id: OTP-14346</p>
+ </item>
+ <item>
+ <p>Truly asynchronous auto-connect. Earlier, when
+ <c>erlang:send</c> was aimed toward an unconnected node,
+ the function would not return until the connection setup
+ had completed (or failed). Now the function returns
+ directly after the message has been enqueued and the
+ connection setup started.</p>
+ <p>The same applies to all distributed operations that
+ may trigger auto-connect, i.e. <c>'!'</c>, <c>send</c>,
+ <c>link</c>, <c>monitor</c>, <c>monitor_node</c>,
+ <c>exit/2</c> and <c>group_leader</c>.</p>
+ <p>The interface for all these functions are unchanged as
+ they do not return connection failures. The only
+ exception is <c>erlang:monitor</c> where a <em>possible
+ incompatibility</em> is introduced: An attempt to monitor
+ a process on a primitive node (such as erl_interface or
+ jinterface), where remote process monitoring is not
+ implemented, will no longer fail with <c>badarg</c>
+ exception. Instead a monitor will be created, but it will
+ only supervise the connection to the node.</p>
+ <p>
+ *** POTENTIAL INCOMPATIBILITY ***</p>
+ <p>
+ Own Id: OTP-14370</p>
+ </item>
+ <item>
+ <p>Changed the default behaviour of <c>.erlang</c>
+ loading: <c>.erlang</c> is no longer loaded from the
+ current directory. <c>c:erlangrc(PathList)</c> can be
+ used to search and load an <c>.erlang</c> file from user
+ specified directories.</p> <p><c>escript</c>,
+ <c>erlc</c>, <c>dialyzer</c> and <c>typer</c> no longer
+ load an <c>.erlang</c> at all.</p>
+ <p>
+ *** POTENTIAL INCOMPATIBILITY ***</p>
+ <p>
+ Own Id: OTP-14439</p>
+ </item>
+ <item>
+ <p>
+ New functionality for implementation of alternative
+ carriers for the Erlang distribution has been introduced.
+ This mainly consists of support for usage of distribution
+ controller processes (previously only ports could be used
+ as distribution controllers). For more information see
+ <seealso marker="erts:alt_dist#distribution_module">ERTS
+ User's Guide ➜ How to implement an Alternative Carrier
+ for the Erlang Distribution ➜ Distribution
+ Module</seealso>.</p>
+ <p>
+ Own Id: OTP-14459</p>
+ </item>
+ <item>
+ <p>
+ Add support for the lcc compiler and in extension the
+ Elbrus 2000 platform.</p>
+ <p>
+ Own Id: OTP-14492</p>
+ </item>
+ <item>
+ <p>Support for "tuple calls" have been removed from the
+ run-time system. Tuple calls was an undocumented and
+ unsupported feature which allowed the module argument for
+ an apply operation to be a tuple: <c>Var = dict:new(),
+ Var:size()</c>. This "feature" frequently caused
+ confusion, especially when such call failed. The
+ stacktrace would point out functions that don't exist in
+ the source code.</p>
+ <p>For legacy code that need to use parameterized modules
+ or tuple calls for some other reason, there is a new
+ compiler option called <c>tuple_calls</c>. When this
+ option is given, the compiler will generate extra code
+ that emulates the old behavior for calls where the module
+ is a variable.</p>
+ <p>
+ *** POTENTIAL INCOMPATIBILITY ***</p>
+ <p>
+ Own Id: OTP-14497</p>
+ </item>
+ <item>
+ <p>Creation of small maps with literal keys has been
+ optimized to be faster and potentially use less memory.
+ The keys are combined into a literal key tuple which is
+ put into the literal pool. The key tuple can be shared
+ between many instances of maps having the same keys.</p>
+ <p>
+ Own Id: OTP-14502</p>
+ </item>
+ <item>
+ <p>
+ When an exception is thrown, include the arguments of the
+ call in the stacktrace for BIFs <c>band</c>, <c>bor</c>,
+ <c>bsl</c>, <c>bsr</c>, <c>bxor</c>, <c>div</c>,
+ <c>rem</c> and the operators <c>+</c>, <c>-</c>, <c>*</c>
+ and <c>/</c>.</p>
+ <p>
+ *** POTENTIAL INCOMPATIBILITY ***</p>
+ <p>
+ Own Id: OTP-14508</p>
+ </item>
+ <item>
+ <p>
+ The non-smp emulators have been removed. This means that
+ the configure options <c>--disable-threads</c> and
+ <c>--enable-plain-emulator</c> have been removed and
+ configure will now refuse to build Erlang/OTP on
+ platforms without thread support.</p>
+ <p>
+ In order to achieve a similar setup as the non-smp
+ emulator, it is possible to start Erlang/OTP with the
+ <c>+S 1</c> option.</p>
+ <p>
+ *** POTENTIAL INCOMPATIBILITY ***</p>
+ <p>
+ Own Id: OTP-14518</p>
+ </item>
+ <item>
+ <p>Modules that use floating point constants compiled
+ with R15 or earlier will need to be re-compiled before
+ they can be loaded.</p>
+ <p>
+ Own Id: OTP-14575</p>
+ </item>
+ <item>
+ <p>
+ Implementation of true asynchronous signaling between
+ processes in order to improve scalability. Signals
+ affected include exit, monitor, demonitor, monitor
+ triggered, link, unlink, and group leader.</p>
+ <p>
+ Own Id: OTP-14589</p>
+ </item>
+ <item>
+ <p>
+ Added a PGO (profile guided optimization) pass to the
+ build step of erts. This can be disabled by passing
+ --disable-pgo to configure.</p>
+ <p>
+ Own Id: OTP-14604</p>
+ </item>
+ <item>
+ <p>
+ Improved the performance of <c>binary:split</c> and
+ <c>binary:match</c>.</p>
+ <p>
+ Own Id: OTP-14610 Aux Id: PR-1480 </p>
+ </item>
+ <item>
+ <p>
+ It is not longer possible to disable dirty schedulers
+ when building erlang.</p>
+ <p>
+ Own Id: OTP-14613</p>
+ </item>
+ <item>
+ <p>Loaded BEAM code in a 64-bit system requires less
+ memory because of better packing of operands for
+ instructions.</p>
+ <p>These memory savings were achieved by major
+ improvements to the <c>beam_makeops</c> scripts used when
+ building the run time system and BEAM compiler. There is
+ also new for documentation for <c>beam_makeops</c> that
+ describes how new BEAM instructions and loader
+ transformations can be implemented. The documentation is
+ found in here in a source directory or git repository:
+ erts/emulator/internal_doc/beam_makeops.md. An online
+ version can be found here:
+ https://github.com/erlang/otp/blob/master/erts/emulator/internal_doc/beam_makeops.md</p>
+ <p>
+ Own Id: OTP-14626</p>
+ </item>
+ <item>
+ <p><c>file:read_file</c> has been changed to read the
+ content of files that report a size of 0 even when data
+ can be read from them. An example of such a file is
+ <c>/proc/cpuinfo</c> on Linux.</p>
+ <p>
+ Own Id: OTP-14637 Aux Id: ERL-327 PR-1524 </p>
+ </item>
+ <item>
+ <p>
+ It is no longer possible to disable the <c>temp_alloc</c>
+ allocator. Disabling it caused serious performance
+ degradations and was never what was wanted.</p>
+ <p>
+ Own Id: OTP-14651</p>
+ </item>
+ <item>
+ <p>The reduction cost of sending messages is now
+ constant. It will no longer scale according to the length
+ of the receiving process' message queue.</p>
+ <p>
+ Own Id: OTP-14667</p>
+ </item>
+ <item>
+ <p>
+ Improved loading of modules with <c>-on_load</c>
+ directive, to no longer block all schedulers when the
+ load operation is completed.</p>
+ <p>
+ Own Id: OTP-14680</p>
+ </item>
+ <item>
+ <p>
+ On platforms with real-time signals available, SIGRTMIN+1
+ is now used as the internal scheduler suspend signal
+ instead of SIGUSR2.</p>
+ <p>
+ Own Id: OTP-14682</p>
+ </item>
+ <item>
+ <p>When the value returned from a '<c>catch</c>'
+ expression is ignored, no stacktrace will be built if an
+ exception is caught. That will save time and produce less
+ garbage. There are also some minor optimizations of
+ '<c>try</c>/<c>catch</c>' both in the compiler and
+ run-time system.</p>
+ <p>
+ Own Id: OTP-14683</p>
+ </item>
+ <item>
+ <p>The guarantees and non-guarantees of
+ <c>erlang:get_stacktrace/0</c> are now documented.</p>
+ <p>
+ Own Id: OTP-14687</p>
+ </item>
+ <item>
+ <p>There is a new syntax in '<c>try/catch</c>' for
+ retrieving the stacktrace without calling
+ '<c>erlang:get_stacktrace/0</c>'. See the reference
+ manual for a description of the new syntax. The
+ '<c>erlang:get_stacktrace/0</c>' BIF is now
+ deprecated.</p>
+ <p>
+ Own Id: OTP-14692</p>
+ </item>
+ <item>
+ <p>
+ New 'used' option for <c>binary_to_term/2</c> that will
+ also return number of bytes actually read from the
+ binary. This enables easy access to any extra data in the
+ binary located directly after the returned term.</p>
+ <p>
+ Own Id: OTP-14780</p>
+ </item>
+ <item>
+ <p>
+ Added more statistics for
+ <c>erlang:system_info({allocator,A})</c> in the
+ <c>mbcs_pool</c> section.</p>
+ <p>
+ Own Id: OTP-14795 Aux Id: ERL-88 </p>
+ </item>
+ <item>
+ <p>Added <c>enif_ioq_peek_head</c> to retrieve Erlang
+ terms from NIF IO queues without having to resort to
+ copying.</p>
+ <p>
+ Own Id: OTP-14797</p>
+ </item>
+ <item>
+ <p>There is a new option '<c>makedep_side_effect</c>' for
+ the compiler and <c>-MMD</c> for '<c>erlc</c>' that
+ generates dependencies and continues to compile as
+ normal.</p>
+ <p>
+ Own Id: OTP-14830</p>
+ </item>
+ <item>
+ <p>Added <c>ets:whereis/1</c> for retrieving the table
+ identifier of a named table.</p>
+ <p>
+ Own Id: OTP-14884</p>
+ </item>
+ <item>
+ <p><c>seq_trace</c> labels may now be any erlang
+ term.</p>
+ <p>
+ Own Id: OTP-14899</p>
+ </item>
+ <item>
+ <p>
+ Optimized the common case of <c>monitor</c> followed by
+ <c>send</c> to the same local process. The monitor signal
+ is now delayed in order to be piggybacked with the sent
+ message and thereby only get one lock operation on the
+ message queue of the receiver. A delayed monitor signal
+ is flushed if no <c>send</c> has been done at the latest
+ when the process is scheduled out.</p>
+ <p>
+ Own Id: OTP-14901</p>
+ </item>
+ <item>
+ <p>
+ Make hipe compiled code work on x86_64 (amd64) with OS
+ security feature PIE, where executable code can be loaded
+ into a random location. Old behavior, if hipe was
+ enabled, was to disable PIE build options for the VM.</p>
+ <p>
+ Own Id: OTP-14903</p>
+ </item>
+ <item>
+ <p>The number of driver async threads will now default to
+ 1 as the standard drivers do not use them anymore. Users
+ that changed this value to tweak the file driver should
+ replace <c>+A</c> with <c>+SDio</c> since it now uses
+ dirty IO schedulers instead of async threads.</p>
+ <p>
+ *** POTENTIAL INCOMPATIBILITY ***</p>
+ <p>
+ Own Id: OTP-14928</p>
+ </item>
+ <item>
+ <p>
+ Optimize <c>==</c> and <c>/=</c> for binaries with
+ different sizes to be constant in time instead of
+ proportional to the size of their common prefix.</p>
+ <p>
+ Own Id: OTP-14934 Aux Id: PR-1708 </p>
+ </item>
+ <item>
+ <p>
+ Refactorings making some internal process flags available
+ for other usage.</p>
+ <p>
+ Own Id: OTP-14948</p>
+ </item>
+ <item>
+ <p>
+ Removed need for HiPE to allocate native executable
+ memory in low 2GB address space on x86_64. Command line
+ option <c>+MXscs</c> is thereby obsolete and ignored.</p>
+ <p>
+ Own Id: OTP-14951</p>
+ </item>
+ <item>
+ <p>Added <c>enif_make_map_from_arrays</c> for creating a
+ populated map, analogous to
+ <c>enif_make_list_from_array</c>.</p>
+ <p>
+ Own Id: OTP-14954</p>
+ </item>
+ <item>
+ <p>Added configuration switches for busy-wait and wake up
+ thresholds for dirty schedulers, and changing these
+ settings for normal schedulers will no longer affect
+ dirty schedulers. </p> <p>Refer to the documentation for
+ details. The new switches are <seealso
+ marker="erl#+sbwtdcpu">+sbwtdcpu</seealso>, <seealso
+ marker="erl#+sbwtdio">+sbwtdio</seealso>, <seealso
+ marker="erl#+swtdcpu">+swtdcpu</seealso>, and <seealso
+ marker="erl#+swtdio">+swtdio</seealso>.</p> <p>The
+ default busy wait threshold for dirty scheduler threads
+ has also been lowered to <c>short</c>.</p>
+ <p>
+ Own Id: OTP-14959</p>
+ </item>
+ <item>
+ <p>
+ The list of "taints" now also includes dynamic loaded
+ drivers in addition to NIF libraries. Statically linked
+ drivers and NIF libraries that are part of erts are not
+ included. The "taints" are returned by
+ <c>system_info(taints)</c> and printed in the header of
+ <c>erl_crash.dump</c> files.</p>
+ <p>
+ Own Id: OTP-14960</p>
+ </item>
+ <item>
+ <p>Added <c>instrument:allocations</c> and
+ <c>instrument:carriers</c> for retrieving information
+ about memory utilization and fragmentation.</p>
+ <p>The old <c>instrument</c> interface has been removed,
+ as have the related options <c>+Mim</c> and
+ <c>+Mis</c>.</p>
+ <p>
+ *** POTENTIAL INCOMPATIBILITY ***</p>
+ <p>
+ Own Id: OTP-14961</p>
+ </item>
+ <item>
+ <p>The process suspend functionality used by the <seealso
+ marker="erlang#suspend_process/2">erlang:suspend_process/2</seealso>
+ BIF has been reimplemented using the newly introduced
+ true asynchronous signaling between processes. This
+ mainly to reduce memory usage in the process control
+ block of all processes, but also in order to simplify the
+ implementation.</p> <warning> <p>You can easily create
+ deadlocks if processes suspends each other (directly or
+ in circles). In ERTS versions prior to ERTS version 10.0,
+ the runtime system prevented such deadlocks, but this
+ prevention has now been removed due to performance
+ reasons.</p> </warning> <p>Other ERTS internal
+ functionality that used the previous process suspend
+ functionality have also been reimplemented to use
+ asynchronous signaling instead.</p>
+ <p>
+ *** POTENTIAL INCOMPATIBILITY ***</p>
+ <p>
+ Own Id: OTP-14964 Aux Id: OTP-14589 </p>
+ </item>
+ <item>
+ <p>Added the <c>nifs</c> option to
+ <c>?MODULE:module_info/1</c> for listing a module's
+ installed NIF functions.</p>
+ <p>
+ Own Id: OTP-14965</p>
+ </item>
+ <item>
+ <p>
+ New implementation of <c>erlang:process_info/[1,2]</c>.</p>
+ <p>
+ In the general case when inspecting another process, the
+ new implementation sends an asynchronous process-info
+ request signal to the other process and waits for the
+ result instead of locking the other process and reading
+ the result directly. In some special cases where no
+ conflicts occur, signal order wont be violated, and the
+ amount of data requested is guaranteed to be small, the
+ inspected process may be inspected directly.</p>
+ <p>
+ Appropriate amount of reductions are now also bumped when
+ inspecting a process.</p>
+ <p>
+ Own Id: OTP-14966</p>
+ </item>
+ <item>
+ <p>
+ Removed process start time from crash dump in order to
+ save memory in process control block.</p>
+ <p>
+ Own Id: OTP-14975 Aux Id: PR-1597 </p>
+ </item>
+ <item>
+ <p>
+ Optimize <c>erlang:put/2</c> when updating existing key
+ with a new immediate value (atom, small integer, pid,
+ port).</p>
+ <p>
+ Own Id: OTP-14976</p>
+ </item>
+ <item>
+ <p>
+ <c>erlang:process_info/1</c> has been changed to no
+ longer include <c>messages</c> by default. Instead
+ <c>erlang:process_info/2</c> should be used.</p>
+ <p>
+ *** POTENTIAL INCOMPATIBILITY ***</p>
+ <p>
+ Own Id: OTP-14986 Aux Id: PR-1745 </p>
+ </item>
+ <item>
+ <p>
+ New <c>erlang:system_info(ets_count)</c> to get total
+ number of ets tables existing at the local node.</p>
+ <p>
+ Own Id: OTP-14987</p>
+ </item>
+ <item>
+ <p>
+ New NIF functions: <c>enif_mutex_name</c>,
+ <c>enif_cond_name</c>, <c>enif_rwlock_name</c>,
+ <c>enif_thread_name</c>, <c>enif_vfprintf</c>,
+ <c>enif_vsnprintf</c>.</p>
+ <p>
+ Own Id: OTP-14994</p>
+ </item>
+ <item>
+ <p>When <c>erlang:system_flag(backtrace_depth, 0)</c> has
+ been called, all exceptions will now contain the entry
+ for <em>one</em> function (despite the zero). It used to
+ be that a hand-made stack backtrace passed to
+ <c>erlang:raise/3</c> would be be truncated to an empty
+ list.</p>
+ <p>
+ Own Id: OTP-15026</p>
+ </item>
+ <item>
+ <p>
+ Fixed bug for named <c>ets</c> tables which could cause
+ unexpected results from matchspec iteration functions
+ (<c>ets:select*</c> and <c>ets:match*</c>) if the table
+ was deleted and recreated with the same name during the
+ iteration. The iteration could incorrectly continue
+ through the recreated table. The expected correct
+ behavior is now for the iteration call to fail with a
+ <c>badarg</c> exception if the table is deleted before
+ the iteration has completed.</p>
+ <p>
+ Own Id: OTP-15031</p>
+ </item>
+ <item>
+ <p>Two new guards BIFs operating on maps have been added:
+ <c>map_get/2</c> and <c>is_map_key/2</c>. They do the
+ same as <c>maps:get/2</c> and <c>maps:is_key/2</c>,
+ respectively, except that they are allowed to be used in
+ guards.</p>
+ <p>
+ Own Id: OTP-15037 Aux Id: PR-1784, PR-1802 </p>
+ </item>
+ <item>
+ <p>
+ Release run-queue lock while cleaning up terminated dirty
+ process.</p>
+ <p>
+ Own Id: OTP-15081</p>
+ </item>
+ <item>
+ <p>The callback module passed as <c>-epmd_module</c> to
+ erl has been expanded to be able to do name and port
+ resolving.</p> <p>Documentation has also been added in
+ the <seealso
+ marker="kernel:erl_epmd"><c>erl_epmd</c></seealso>
+ reference manual and ERTS User's Guide <seealso
+ marker="erts:alt_disco">How to Implement an Alternative
+ Service Discovery for Erlang Distribution</seealso>.</p>
+ <p>
+ Own Id: OTP-15086 Aux Id: PR-1694 </p>
+ </item>
+ </list>
+ </section>
+
+</section>
+
+<section><title>Erts 9.3.3.6</title>
+
+ <section><title>Improvements and New Features</title>
+ <list>
+ <item>
+ <p>List subtraction (The <c>--</c> operator) will now
+ yield properly on large inputs.</p>
+ <p>
+ Own Id: OTP-15371</p>
+ </item>
+ </list>
+ </section>
+
+</section>
+
+<section><title>Erts 9.3.3.5</title>
+
+ <section><title>Fixed Bugs and Malfunctions</title>
+ <list>
+ <item>
+ <p>
+ ERTS internal trees of monitor structures could get into
+ an inconsistent state. This could cause <c>'DOWN'</c>
+ messages not to be delivered when they should, as well as
+ delivery of <c>'DOWN'</c> messages that should not be
+ delivered.</p>
+ <p>
+ This bug was introduced in ERTS version 9.0 (OTP 20.0)
+ and was fixed in ERTS version 10.0 (OTP 21.0) due to a
+ rewrite of the monitor code. That is, this bug only exist
+ in the OTP 20 release.</p>
+ <p>
+ Own Id: OTP-15399 Aux Id: ERL-751, ERIERL-262, OTP-14205 </p>
+ </item>
+ </list>
+ </section>
+
+</section>
+
+<section><title>Erts 9.3.3.4</title>
+
+ <section><title>Fixed Bugs and Malfunctions</title>
+ <list>
+ <item>
+ <p>
+ Fixed bug in <c>ets:select_replace</c> when called with a
+ fully bound key could cause a following call to
+ <c>ets:next</c> or <c>ets:prev</c> to crash the emulator
+ or return invalid result.</p>
+ <p>
+ Own Id: OTP-15346</p>
+ </item>
+ </list>
+ </section>
+
+</section>
+
+<section><title>Erts 9.3.3.3</title>
+
+ <section><title>Fixed Bugs and Malfunctions</title>
+ <list>
+ <item>
+ <p>
+ Fixed a bug which caused an emulator crash when
+ <c>enif_send()</c> was called by a NIF that executed on a
+ dirty scheduler. The bug was either triggered when the
+ NIF called <c>enif_send()</c> without a message
+ environment, or when the process executing the NIF was
+ <c>send</c> traced.</p>
+ <p>
+ Own Id: OTP-15223</p>
+ </item>
+ <item>
+ <p>
+ Fixed a bug causing some Erlang references to be
+ inconsistently ordered. This could for example cause
+ failure to look up certain elements with references as
+ keys in search data structures. This bug was introduced
+ in R13B02.</p>
+ <p>
+ Thanks to Simon Cornish for finding the bug and supplying
+ a fix.</p>
+ <p>
+ *** POTENTIAL INCOMPATIBILITY ***</p>
+ <p>
+ Own Id: OTP-15225</p>
+ </item>
+ </list>
+ </section>
+
+</section>
+
+<section><title>Erts 9.3.3.2</title>
+
+ <section><title>Fixed Bugs and Malfunctions</title>
+ <list>
+ <item>
+ <p>Fixed a race condition in the inet driver that could
+ cause receive to hang when the emulator was compiled with
+ gcc 8.</p>
+ <p>
+ Own Id: OTP-15158 Aux Id: ERL-654 </p>
+ </item>
+ <item>
+ <p>
+ Fix bug in generation of erl_crash.dump, which could
+ cause VM to crash.</p>
+ <p>
+ Bug exist since erts-9.2 (OTP-20.2).</p>
+ <p>
+ Own Id: OTP-15181</p>
+ </item>
+ </list>
+ </section>
+
+</section>
+
+<section><title>Erts 9.3.3.1</title>
+
+ <section><title>Fixed Bugs and Malfunctions</title>
+ <list>
+ <item>
+ <p>Fixed a rare bug that could cause processes to be
+ scheduled after they had been freed.</p>
+ <p>
+ Own Id: OTP-15067 Aux Id: ERL-573 </p>
+ </item>
+ </list>
+ </section>
+
+</section>
+
+<section><title>Erts 9.3.3</title>
+
+ <section><title>Fixed Bugs and Malfunctions</title>
+ <list>
+ <item>
+ <p>
+ Fixed bug in <c>ets</c> that could cause VM crash if
+ process A terminates after fixating a table and process B
+ deletes the table at "the same time". The table fixation
+ could be done with <c>ets:safe_fixtable</c> or if process
+ A terminates in the middle of a long running
+ <c>select</c> or <c>match</c> call.</p>
+ <p>
+ Own Id: OTP-15109</p>
+ </item>
+ </list>
+ </section>
+
+</section>
+
+<section><title>Erts 9.3.2</title>
+
+ <section><title>Fixed Bugs and Malfunctions</title>
+ <list>
+ <item>
+ <p>
+ Fixed bug in <c>enif_binary_to_term</c> which could cause
+ memory corruption for immediate terms (atoms, small
+ integers, pids, ports, empty lists).</p>
+ <p>
+ Own Id: OTP-15080</p>
+ </item>
+ <item>
+ <p>
+ Fixed bug in <c>erlang:system_profile/2</c> that could
+ cause superfluous <c>{profile,_,active,_,_}</c> messages
+ for terminating processes.</p>
+ <p>
+ Own Id: OTP-15085</p>
+ </item>
+ </list>
+ </section>
+
+</section>
+
+<section><title>Erts 9.3.1</title>
+
+ <section><title>Fixed Bugs and Malfunctions</title>
+ <list>
+ <item>
+ <p>Fixed a crash in <c>heart:get_cmd/0</c> when the
+ stored command was too long.</p>
+ <p>
+ Own Id: OTP-15034</p>
+ </item>
+ </list>
+ </section>
+
+</section>
+
+<section><title>Erts 9.3</title>
+
+ <section><title>Fixed Bugs and Malfunctions</title>
+ <list>
+ <item>
+ <p>
+ Fixed a <c>configure</c> test for <c>libz</c> internals
+ that unintentionally caused various native code in OTP to
+ link against <c>libz</c>. Under certain circumstances
+ this caused the build of OTP to fail.</p>
+ <p>
+ Own Id: OTP-14840 Aux Id: ERL-529 </p>
+ </item>
+ <item>
+ <p>
+ File names containing unicode codepoints larger than 255
+ were not correctly encoded in stack traces.</p>
+ <p>
+ Own Id: OTP-14847 Aux Id: ERL-544 </p>
+ </item>
+ <item>
+ <p>
+ Fix HiPE bug for binary constructs like
+ <c>&lt;&lt;X/utf8&gt;&gt;</c> which could in rare cases
+ cause faulty results or VM crash.</p>
+ <p>
+ This fix affects both the <c>hipe</c> compiler and
+ <c>erts</c> runtime in an <em>incompatible</em> way. Old
+ hipe compiled files need to be recompiled to load and run
+ properly as native.</p>
+ <p>
+ *** POTENTIAL INCOMPATIBILITY ***</p>
+ <p>
+ Own Id: OTP-14850 Aux Id: PR-1664 </p>
+ </item>
+ <item>
+ <p>
+ Fix <c>term_to_binary/2</c> spec for
+ <c>minor_version</c>.</p>
+ <p>
+ Own Id: OTP-14876 Aux Id: ERL-548 </p>
+ </item>
+ <item>
+ <p>
+ Fix bug in erlang:binary_to_integer/2 where invalid
+ characters were not detected for bases larger then 10.
+ e.g. <c>binary_to_integer(&lt;&lt;":"&gt;&gt;, 16)</c>
+ would return 3 and not badarg as it should.</p>
+ <p>
+ Own Id: OTP-14879</p>
+ </item>
+ <item>
+ <p>Fixed bug in <c>float_to_list/2</c> and
+ <c>float_to_binary/2</c> with option <c>decimals</c> that
+ caused a faulty rounding up of the last decimal digit for
+ about 6% of floats with a fraction part.</p>
+ <p>For example, <c>float_to_list(0.145,
+ [{decimals,1}])</c> returned <c>"0.2"</c> instead of
+ <c>"0.1"</c>.</p>
+ <p>
+ Own Id: OTP-14890</p>
+ </item>
+ <item>
+ <p>
+ Fix bug causing slow hipe execution in modules loaded
+ early during boot or loaded by <c>code:atomic_load</c> or
+ <c>code:finish_loading</c>.</p>
+ <p>
+ Own Id: OTP-14891</p>
+ </item>
+ <item>
+ <p>Fixed a buffer overflow in an internal string
+ formatting function that could be hit if specifying a
+ long floating-point format specifier to
+ <c>erts_sprintf</c> or similar.</p>
+ <p>
+ Own Id: OTP-14920</p>
+ </item>
+ <item>
+ <p><c>erlang:iolist_to_iovec/1</c> and
+ <c>enif_inspect_iovec</c> will no longer fail when
+ provided with binaries that have been matched-out on a
+ non-byte boundary.</p>
+ <p>
+ Own Id: OTP-14921</p>
+ </item>
+ <item>
+ <p><c>iolist_to_binary/1</c> and
+ <c>erlang:iolist_to_iovec/1</c> will now badarg if
+ supplied with a bitstring (without a list).</p>
+ <p>
+ Own Id: OTP-14926</p>
+ </item>
+ <item>
+ <p>
+ Reject loading modules with names containing directory
+ separators ('/' or '\' on Windows).</p>
+ <p>
+ Own Id: OTP-14933 Aux Id: ERL-564, PR-1716 </p>
+ </item>
+ <item>
+ <p>
+ Fix potential dead-lock when the tracer process dies
+ while a the traced process is running on a dirty
+ scheduler.</p>
+ <p>
+ Own Id: OTP-14938</p>
+ </item>
+ </list>
+ </section>
+
+
+ <section><title>Improvements and New Features</title>
+ <list>
+ <item>
+ <p>
+ More crash dump info such as: process binary virtual heap
+ stats, full info for process causing out-of-mem during
+ GC, more port related info, and dirty scheduler info.</p>
+ <p>
+ Own Id: OTP-14820</p>
+ </item>
+ </list>
+ </section>
+
+</section>
+
+<section><title>Erts 9.2.1</title>
+
+ <section><title>Improvements and New Features</title>
+ <list>
+ <item>
+ <p>
+ Improve search algorithm of abandoned memory carriers.
+ Instead of limited linear search, each allocator instance
+ maintain a balanced search tree of all its abandoned
+ carriers for faster and more exhaustive search.</p>
+ <p>
+ Own Id: OTP-14915 Aux Id: ERIERL-88 </p>
+ </item>
+ <item>
+ <p>
+ New erts_alloc command line options <c>+M_acnl</c> and
+ <c>+M_acfml</c> to limit carrier abandonment.</p>
+ <p>
+ Own Id: OTP-14916 Aux Id: ERIERL-88 </p>
+ </item>
+ <item>
+ <p>
+ New family of <c>erts_alloc</c> strategies: Age Order
+ First Fit. Similar to "address order", but instead the
+ oldest possible carrier is always chosen for allocation.</p>
+ <p>
+ Own Id: OTP-14917 Aux Id: ERIERL-88 </p>
+ </item>
+ <item>
+ <p>
+ Add possibility to change allocator options at runtime
+ with <c>system_info(erts_alloc, ...)</c>. Only option
+ <c>sbct</c> (single block carrier threshold) is currently
+ supported via this interface.</p>
+ <p>
+ Own Id: OTP-14918 Aux Id: ERIERL-88 </p>
+ </item>
+ </list>
+ </section>
+
+</section>
+
+<section><title>Erts 9.2</title>
+
+ <section><title>Fixed Bugs and Malfunctions</title>
+ <list>
+ <item>
+ <p>
+ Fix a bug in tracing where the {caller} match spec
+ function would be set to undefined incorrectly when used
+ in conjunction with return_to or return_trace on some
+ functions.</p>
+ <p>
+ The functions effected are: erlang:put/2, erlang:erase/1,
+ erlang:process_info/1,2, erlang:nif_load/2,
+ erts_internal:garbage_collection/1 and
+ erts_internal:check_process_code/1.</p>
+ <p>
+ Because of this bug, the analysis done by fprof could
+ become incorrect when the functions above are the
+ tail-call in a function.</p>
+ <p>
+ Own Id: OTP-14677</p>
+ </item>
+ <item>
+ <p>
+ Fix emulator deadlock that would happen if
+ <c>trap_exit</c> was set to true and a process sends an
+ exit signal to itself using <c>exit(self(), Reason)</c>
+ while receive tracing was enabled for that process.</p>
+ <p>
+ Own Id: OTP-14678 Aux Id: ERL-495 </p>
+ </item>
+ <item>
+ <p>Writing of crash dumps is significantly faster.</p>
+ <p>Maps are now included in crash dumps.</p>
+ <p>Constants terms would only be shown in one process,
+ while other processes referencing the same constant term
+ would show a marker for incomplete heap. </p>
+ <p>
+ Own Id: OTP-14685 Aux Id: OTP-14611, OTP-14603, OTP-14595 </p>
+ </item>
+ <item>
+ <p>
+ The fallback home directory for windows has been changed
+ to be the PROFILE directory instead of the WINDOWS
+ directory. The fallback is used when the environment
+ variables HOMEDRIVE and HOMEPATH have not been set.</p>
+ <p>
+ Own Id: OTP-14691</p>
+ </item>
+ <item>
+ <p>
+ Fix bug for hipe compiled code using
+ <c>&lt;&lt;X/utf32&gt;&gt;</c> binary construction that
+ could cause faulty result or even VM crash.</p>
+ <p>
+ On architectures other than x86_64, code need to be
+ recompiled to benefit from this fix.</p>
+ <p>
+ Own Id: OTP-14740</p>
+ </item>
+ <item>
+ <p>
+ Fixed bug in <c>erlang:garbage_collect/2</c> and
+ <c>erlang:check_process_code/3</c>, when called with
+ option <c>{async,ReqestId}</c>. Could cause VM crash or
+ heap corruption if <c>RequestId</c> was an immediate term
+ (like a pid, atom or small integer). Bug exists since
+ OTP-17.0.</p>
+ <p>
+ Own Id: OTP-14752</p>
+ </item>
+ <item>
+ <p>ERL_NIF_MINOR_VERSION wasn't bumped with the addition
+ of <c>enif_ioq_*</c>.</p>
+ <p>
+ Own Id: OTP-14779</p>
+ </item>
+ <item>
+ <p>Purging of loaded code that contained "fake literals"
+ (for example the magic reference obtained from
+ '<c>ets:new/2</c>') would crash the runtime system.
+ Corrected.</p>
+ <p>
+ Own Id: OTP-14791</p>
+ </item>
+ <item>
+ <p>Setting the size of the atom table to a number near
+ 2147483647 (using the '<c>+t</c>' option) would cause the
+ emulator to exit with a failure to allocate a huge amount
+ of memory. This has been corrected. Also the usage
+ message for the '<c>+t</c>' option has been corrected to
+ show the correct upper limit 2147483647 instead of 0.</p>
+ <p>
+ Own Id: OTP-14796</p>
+ </item>
+ <item>
+ <p>Fixed a bug that prevented registered process names
+ from being resolved in lcnt results.</p>
+ <p>
+ Own Id: OTP-14803</p>
+ </item>
+ <item>
+ <p>Formatting bugs were fixed in several HiPE debug
+ BIFs.</p>
+ <p>
+ Own Id: OTP-14804</p>
+ </item>
+ </list>
+ </section>
+
+
+ <section><title>Improvements and New Features</title>
+ <list>
+ <item>
+ <p>Binaries and some other data in crash dumps are now
+ encoded in base64 (instead of in hex), which will reduce
+ the size of crash dumps.</p>
+ <p>A few bugs in the handling of sub binaries in
+ <c>crashdump_viewer</c> have been fixed.</p>
+ <p>
+ Own Id: OTP-14686</p>
+ </item>
+ <item>
+ <p>
+ Micro optimization for send operations of messages to
+ other nodes. The local ack-message, which is otherwise
+ sent back from TPC/IP port driver to sending client
+ process, is now ignored earlier for distributed send
+ operations.</p>
+ <p>
+ Own Id: OTP-14689</p>
+ </item>
+ </list>
+ </section>
+
+</section>
+
+<section><title>Erts 9.1.5</title>
+
+ <section><title>Fixed Bugs and Malfunctions</title>
+ <list>
+ <item>
+ <p>Fixed a bug in file closure on Unix; close(2) was
+ retried on EINTR which could cause a different (recently
+ opened) file to be closed as well.</p>
+ <p>
+ Own Id: OTP-14775</p>
+ </item>
+ <item>
+ <p>
+ A race-condition when tearing down a connection with
+ active node monitors could cause the runtime system to
+ crash.</p>
+ <p>
+ This bug was introduced in ERTS version 8.0 (OTP 19.0).</p>
+ <p>
+ Own Id: OTP-14781 Aux Id: OTP-13047 </p>
+ </item>
+ </list>
+ </section>
+
+</section>
+
+<section><title>Erts 9.1.4</title>
+
+ <section><title>Fixed Bugs and Malfunctions</title>
+ <list>
+ <item>
+ <p>Microstate accounting sometimes produced incorrect
+ results for dirty schedulers.</p>
+ <p>
+ Own Id: OTP-14707</p>
+ </item>
+ <item>
+ <p>Fixed a regression in <c>zlib:gunzip/1</c> that
+ prevented it from working when the decompressed size was
+ a perfect multiple of 16384. This regression was
+ introduced in 20.1.1</p>
+ <p>
+ Own Id: OTP-14730 Aux Id: ERL-507 </p>
+ </item>
+ <item>
+ <p>Fixed a memory corruption bug in
+ <c>enif_inspect_iovec</c>; writable binaries stayed
+ writable after entering the iovec.</p>
+ <p>
+ Own Id: OTP-14745</p>
+ </item>
+ <item>
+ <p>Fixed a crash in <c>enif_inspect_iovec</c> on
+ encountering empty binaries.</p>
+ <p>
+ Own Id: OTP-14750</p>
+ </item>
+ <item>
+ <p><c>zlib:deflateParams/3</c> will no longer return
+ <c>buf_error</c> when called after <c>zlib:deflate/2</c>
+ with zlib <c>1.2.11</c>.</p>
+ <p>
+ Own Id: OTP-14751</p>
+ </item>
+ </list>
+ </section>
+
+</section>
+
+<section><title>Erts 9.1.3</title>
+
+ <section><title>Fixed Bugs and Malfunctions</title>
+ <list>
+ <item>
+ <p>Added zlib:set_controlling_process/2 to move a
+ zstream() between processes.</p>
+ <p>
+ Own Id: OTP-14672 Aux Id: ERL-494 </p>
+ </item>
+ <item>
+ <p>
+ Fix so that schedulers are bound correctly when the first
+ available cpu is not the first detected cpu. e.g. when
+ using "taskset -c X..Y" when X is not equal to 0.</p>
+ <p>
+ Own Id: OTP-14694</p>
+ </item>
+ </list>
+ </section>
+
+</section>
+
+<section><title>Erts 9.1.2</title>
+
+ <section><title>Fixed Bugs and Malfunctions</title>
+ <list>
+ <item>
+ <p>
+ Fixed bug that could cause a VM crash when a corrupt
+ message is received on distribution channel from other
+ node.</p>
+ <p>
+ Own Id: OTP-14661 Aux Id: ERIERL-80 </p>
+ </item>
+ </list>
+ </section>
+
+</section>
+
+<section><title>Erts 9.1.1</title>
+
+ <section><title>Fixed Bugs and Malfunctions</title>
+ <list>
+ <item>
+ <p>The new zlib module returned a data_error when
+ inflating concatenated streams, which was incompatible
+ with the old module's behavior of returning the
+ uncompressed data up to the end of the first stream.</p>
+ <p>
+ Own Id: OTP-14648</p>
+ </item>
+ <item>
+ <p>zlib:gunzip/1 will no longer stop at the end of the
+ first stream when decompressing concatenated gzip
+ files.</p>
+ <p>
+ Own Id: OTP-14649</p>
+ </item>
+ </list>
+ </section>
+
+</section>
+
+<section><title>Erts 9.1</title>
+
+ <section><title>Fixed Bugs and Malfunctions</title>
+ <list>
+ <item>
+ <p>
+ Changed <c>erlang:apply/2</c> to raise a <c>badarg</c>
+ exception if the second argument is not a proper list.
+ Previous behavior was a misleading <c>undef</c>
+ exception.</p>
+ <p>
+ Own Id: OTP-14490 Aux Id: ERL-432 </p>
+ </item>
+ <item>
+ <p>On macOS, <c>crypto</c> would crash if <c>observer</c>
+ had been started before <c>crypto</c>. On the beta for
+ macOS 10.13 (High Sierra), <c>crypto</c> would crash.
+ Both of those bugs have been fixed.</p>
+ <p>
+ Own Id: OTP-14499 Aux Id: ERL-251 ERL-439 </p>
+ </item>
+ <item>
+ <p>
+ Fixed bug in enif_whereis_pid/port that could cause heap
+ corruption in rare cases.</p>
+ <p>
+ Own Id: OTP-14523</p>
+ </item>
+ <item>
+ <p>
+ Fix so that trace messages generated when in a dirty nif
+ are flushed correctly when the dirty nif is done
+ executing.</p>
+ <p>
+ Own Id: OTP-14538</p>
+ </item>
+ <item>
+ <p>
+ Fix escape code handling when using ANSI color codes in
+ the shell.</p>
+ <p>
+ Own Id: OTP-14549 Aux Id: PR1536 </p>
+ </item>
+ <item>
+ <p>
+ Upgraded the ERTS internal PCRE library from version 8.40
+ to version 8.41. See <url
+ href="http://pcre.org/original/changelog.txt">http://pcre.org/original/changelog.txt</url>
+ for information about changes made to PCRE. This library
+ implements major parts of the <seealso
+ marker="stdlib:re"><c>re</c></seealso> regular
+ expressions module.</p>
+ <p>
+ Own Id: OTP-14574</p>
+ </item>
+ <item>
+ <p>
+ Fixed a bug causing <c>statistics(runtime)</c> to produce
+ negative values and a bug in
+ <c>statistics(wall_clock)</c> causing it to produce
+ values one second too long.</p>
+ <p>
+ <c>statistics(runtime)</c> now also use
+ <c>getrusage()</c> as source when available preventing
+ the returned value from wrapping as frequent as before.</p>
+ <p>
+ Own Id: OTP-14597 Aux Id: ERL-465 </p>
+ </item>
+ <item>
+ <p>
+ Fixed small memory leak that could occur when sending to
+ a terminating port.</p>
+ <p>
+ Own Id: OTP-14609</p>
+ </item>
+ <item>
+ <p>
+ Fix bug causing VM crash when a module with
+ <c>-on_load</c> directive is loaded while
+ <c>erlang:trace(on_load, ...)</c> is enabled.</p>
+ <p>
+ Own Id: OTP-14612</p>
+ </item>
+ <item>
+ <p>A warning that the compiler may optimize away atoms
+ have been added to the documentation of
+ <c>list_to_existing_atom/1</c> and
+ <c>binary_to_existing_atom/2</c>.</p>
+ <p>
+ Own Id: OTP-14614 Aux Id: ERL-453 </p>
+ </item>
+ </list>
+ </section>
+
+
+ <section><title>Improvements and New Features</title>
+ <list>
+ <item>
+ <p>Lock counting can now be fully toggled at runtime in
+ the lock counting emulator (<c>-emu_type lcnt</c>).
+ Everything is enabled by default to match the old
+ behavior, but specific categories can be toggled at will
+ with minimal runtime overhead when disabled. Refer to the
+ documentation on <c>lcnt:rt_mask/1</c> for details.</p>
+ <p>
+ Own Id: OTP-13170</p>
+ </item>
+ <item>
+ <p>The <c>zlib</c> module has been refactored and all its
+ operations will now yield appropriately, allowing them to
+ be used freely in concurrent applications.</p> <p>The
+ following functions have been deprecated, but will not
+ produce compiler warnings until OTP 21:
+ <c>zlib:adler32</c>, <c>zlib:crc32</c>,
+ <c>zlib:inflateChunk</c>, <c>zlib:getBufSize</c>,
+ <c>zlib:setBufSize</c>.</p> <p>The behavior of throwing
+ an error when a dictionary is required for decompression
+ has also been deprecated. Refer to the documentation on
+ <c>inflateSetDictionary/2</c> for details.</p>
+ <p>
+ Own Id: OTP-14185</p>
+ </item>
+ <item>
+ <p><c>lcnt:collect</c> and <c>lcnt:clear</c> will no
+ longer block all other threads in the runtime system.</p>
+ <p>
+ Own Id: OTP-14412</p>
+ </item>
+ <item>
+ <p>Add <c>erlang:iolist_to_iovec/1</c>, which converts an
+ iolist() to an erlang:iovec(), which suitable for use
+ with <c>enif_inspect_iovec</c>.</p>
+ <p>
+ Own Id: OTP-14520</p>
+ </item>
+ <item>
+ <p>When provided with bad arguments, the <c>zlib</c>
+ module will now raise named exceptions instead of just
+ <c>badarg</c>. For example, <c>not_initialized</c> when
+ using <c>zlib:inflate/2</c> with an uninitialized
+ stream.</p>
+ <p>
+ Own Id: OTP-14527</p>
+ </item>
+ <item>
+ <p>
+ <c>erlang:halt/2</c> allows any Unicode string as slogan
+ for the crash dump.</p>
+ <p>
+ Own Id: OTP-14553</p>
+ </item>
+ <item>
+ <p>Add new nif API functions for managing an I/O Queue.
+ The added functions are:</p> <list type="bulleted">
+ <item><seealso marker="erl_nif#enif_ioq_create">
+ <c>enif_ioq_create()</c></seealso></item> <item><seealso
+ marker="erl_nif#enif_ioq_destroy">
+ <c>enif_ioq_destroy()</c></seealso></item> <item><seealso
+ marker="erl_nif#enif_ioq_enq_binary">
+ <c>enif_ioq_enq_binary()</c></seealso></item>
+ <item><seealso marker="erl_nif#enif_ioq_enqv">
+ <c>enif_ioq_enqv()</c></seealso></item> <item><seealso
+ marker="erl_nif#enif_ioq_deq">
+ <c>enif_ioq_deq()</c></seealso></item> <item><seealso
+ marker="erl_nif#enif_ioq_peek">
+ <c>enif_ioq_peek()</c></seealso></item> <item><seealso
+ marker="erl_nif#enif_inspect_iovec">
+ <c>enif_inspect_iovec()</c></seealso></item>
+ <item><seealso marker="erl_nif#enif_free_iovec">
+ <c>enif_free_iovec()</c></seealso></item> </list>
+ <p>
+ Own Id: OTP-14598</p>
+ </item>
+ </list>
+ </section>
+
+</section>
+
+<section><title>Erts 9.0.5</title>
+
+ <section><title>Fixed Bugs and Malfunctions</title>
+ <list>
+ <item>
+ <p>
+ Fixed bug in <c>binary_to_term</c> and
+ <c>binary_to_atom</c> that could cause VM crash.
+ Typically happens when the last character of an UTF8
+ string is in the range 128 to 255, but truncated to only
+ one byte. Bug exists in <c>binary_to_term</c> since ERTS
+ version 5.10.2 (OTP_R16B01) and <c>binary_to_atom</c>
+ since ERTS version 9.0 (OTP-20.0).</p>
+ <p>
+ Own Id: OTP-14590 Aux Id: ERL-474 </p>
+ </item>
+ </list>
+ </section>
+
+</section>
+
+<section><title>Erts 9.0.4</title>
+
+ <section><title>Fixed Bugs and Malfunctions</title>
+ <list>
+ <item>
+ <p>
+ A timer internal bit-field used for storing scheduler id
+ was too small. As a result, VM internal timer data
+ structures could become inconsistent when using 1024
+ schedulers on the system. Note that systems with less
+ than 1024 schedulers are not effected by this bug.</p>
+ <p>
+ This bug was introduced in ERTS version 7.0 (OTP 18.0).</p>
+ <p>
+ Own Id: OTP-14548 Aux Id: OTP-11997, ERL-468 </p>
+ </item>
+ <item>
+ <p>
+ Automatic cleanup of a BIF timer, when the owner process
+ terminated, could race with the timeout of the timer.
+ This could cause the VM internal data structures to
+ become inconsistent which very likely caused a VM crash.</p>
+ <p>
+ This bug was introduced in ERTS version 9.0 (OTP 20.0).</p>
+ <p>
+ Own Id: OTP-14554 Aux Id: OTP-14356, ERL-468 </p>
+ </item>
+ </list>
+ </section>
+
+</section>
+
+<section><title>Erts 9.0.3</title>
+
+ <section><title>Fixed Bugs and Malfunctions</title>
+ <list>
+ <item>
+ <p>Binary append operations did not check for overflow,
+ resulting in nonsensical results when huge binaries were
+ appended.</p>
+ <p>
+ Own Id: OTP-14524</p>
+ </item>
+ </list>
+ </section>
+
+</section>
+
+<section><title>Erts 9.0.2</title>
+
+ <section><title>Fixed Bugs and Malfunctions</title>
+ <list>
+ <item>
+ <p>
+ Added missing release notes for OTP-14491 ("performance
+ bug in pre-allocators") which was included in erts-9.0.1
+ (OTP-20.0.1).</p>
+ <p>
+ Own Id: OTP-14494</p>
+ </item>
+ <item>
+ <p>Fixed a bug that prevented TCP sockets from being
+ closed properly on send timeouts.</p>
+ <p>
+ Own Id: OTP-14509</p>
+ </item>
+ <item>
+ <p>
+ Fixed bug in operator <c>bxor</c> causing erroneuos
+ result when one operand is a big <em>negative</em>
+ integer with the lowest <c>N*W</c> bits as zero and the
+ other operand not larger than <c>N*W</c> bits. <c>N</c>
+ is an integer of 1 or larger and <c>W</c> is 32 or 64
+ depending on word size.</p>
+ <p>
+ Own Id: OTP-14514</p>
+ </item>
+ </list>
+ </section>
+
+</section>
+
+<section><title>Erts 9.0.1</title>
+
+ <section><title>Fixed Bugs and Malfunctions</title>
+ <list>
+ <item>
+ <p>
+ Fixed a bug in gen_tcp:send where it never returned when
+ repeatedly called on a remotely closed TCP socket.</p>
+ <p>
+ Own Id: OTP-13939 Aux Id: ERL-193 </p>
+ </item>
+ <item>
+ <p>
+ Fixed segfault that could happen during cleanup of
+ aborted erlang:port_command/3 calls. A port_command is
+ aborted if the port is closed at the same time as the
+ port_command was issued. This bug was introduced in
+ erts-8.0.</p>
+ <p>
+ Own Id: OTP-14481</p>
+ </item>
+ <item>
+ <p>
+ Fixed implementation of <c>statistics(wall_clock)</c> and
+ <c>statistics(runtime)</c> so that values do not
+ unnecessarily wrap due to the emulator. Note that the
+ values returned by <c>statistics(runtime)</c> may still
+ wrap due to limitations in the underlying functionality
+ provided by the operating system.</p>
+ <p>
+ Own Id: OTP-14484</p>
+ </item>
+ <item>
+ <p>
+ Fix performance bug in pre-allocators that could cause
+ them to permanently fall back on normal more expensive memory
+ allocation. Pre-allocators are used for quick allocation
+ of short lived meta data used by messages and other
+ scheduled tasks. Bug exists since OTP_R15B02.
+ [this release note was missing in erts-9.0.1]</p>
+ <p>
+ Own Id: OTP-14491</p>
+ </item>
+ </list>
+ </section>
+
+</section>
+
+<section><title>Erts 9.0</title>
+ <section><title>Fixed Bugs and Malfunctions</title>
+ <list>
+ <item>
+ <p>Fix various bugs regarding loading, upgrade and purge
+ of HiPE compiled code:</p> <list> <item>The native code
+ memory for a purged module was never deallocated.</item>
+ <item>Wrong functions could in some cases be called after
+ a module upgrade.</item>
+ <item><c>erlang:check_process_code</c> did not check for
+ recursive calls made from native code.</item> </list>
+ <p>
+ Own Id: OTP-13968</p>
+ </item>
+ <item>
+ <p>
+ Hipe optional LLVM backend does require LLVM version 3.9
+ or later as older versions forced strong dependencies on
+ erts internals structures.</p>
+ <p>
+ Own Id: OTP-14238</p>
+ </item>
+ <item>
+ <p>When an exception such as '<c>throw(HugeTerm)</c>' was
+ caught, <c>HugeTerm</c> term would be kept in the process
+ until the next exception occurred, potentially increasing
+ the heap size for the process. That has been
+ corrected.</p>
+ <p>
+ Own Id: OTP-14255 Aux Id: OTP-14400, OTP-14401 </p>
+ </item>
+ <item>
+ <p>
+ Slogans in crash dumps have been extended to print more
+ complex terms.</p>
+ <p>
+ Own Id: OTP-14303</p>
+ </item>
+ <item>
+ <p>
+ Fixed bug when using <c>enif_inspect_binary</c> in
+ combination with <c>enif_copy</c>. In some circumstances
+ the inspected binary could be reallocated by the
+ <c>enif_copy</c> call when it shouldn't have been.</p>
+ <p>
+ Own Id: OTP-14304</p>
+ </item>
+ <item>
+ <p>
+ The address family <c>local</c> (AF_UNIX / AF_LOCAL) now
+ does not ensure zero termination of Linux Abstract
+ Addresses so they can use all bytes.</p>
+ <p>
+ Own Id: OTP-14305</p>
+ </item>
+ <item>
+ <p>
+ Use <c>-fno-PIE</c> for Gentoo Hardened and others that
+ don't accept linker flag <c>-no-pie</c>.</p>
+ <p>
+ Own Id: OTP-14307 Aux Id: PR-1379 </p>
+ </item>
+ <item>
+ <p>
+ Disable hipe for <c>ppc64le</c> architecture (little
+ endian) as it is not, and has never been, supported. It
+ was earlier equated with <c>ppc64</c> (big endian) which
+ lead to broken build without <c>--disable-hipe</c>.</p>
+ <p>
+ Own Id: OTP-14314 Aux Id: ERL-369, PR-1394 </p>
+ </item>
+ <item>
+ <p>
+ Fix 'epmd -kill' to return a failure exit status code if
+ epmd was not killed because of some error.</p>
+ <p>
+ Own Id: OTP-14324</p>
+ </item>
+ <item>
+ <p>Fixed the following dirty scheduler related bugs:</p>
+ <list> <item><p>the <c>+SDPcpu</c> command line argument
+ could cause the amount of dirty CPU schedulers to be set
+ to zero</p></item>
+ <item><p><c>erlang:system_flag(multi_scheduling, _)</c>
+ failed when only one normal scheduler was used together
+ with dirty scheduler support</p></item> </list>
+ <p>
+ Own Id: OTP-14335</p>
+ </item>
+ <item>
+ <p>
+ Fix erlexec to handle mismatch in sysconf and proc fs
+ when figuring out the cpu topology. This behaviour has
+ been seen when using docker together with
+ <c>--cpuset-cpus</c>.</p>
+ <p>
+ Own Id: OTP-14352</p>
+ </item>
+ <item>
+ <p>
+ Fixed memory segment cache used for multiblock carriers.
+ Huge (> 2GB) memory segments could cause a VM crash.
+ Creation of such huge memory segments used for multiblock
+ carriers is however very uncommon.</p>
+ <p>
+ Own Id: OTP-14360 Aux Id: ERL-401, PR-1417 </p>
+ </item>
+ <item>
+ <p>
+ Fix bug causing <c>code:is_module_native</c> to falsely
+ return true when <c>local</c> call trace is enabled for
+ the module.</p>
+ <p>
+ Own Id: OTP-14390</p>
+ </item>
+ <item>
+ <p>
+ Fix emulator crash when receive tracing on a
+ <c>trace_delivered</c> message.</p>
+ <p>
+ Own Id: OTP-14411</p>
+ </item>
+ <item>
+ <p>
+ Fix file:sendfile error handling on SunOS when a
+ connection is closed during transmission.</p>
+ <p>
+ Own Id: OTP-14424</p>
+ </item>
+ <item>
+ <p>
+ <c>escript</c> did not handle paths with spaces correct.</p>
+ <p>
+ Own Id: OTP-14433</p>
+ </item>
+ <item>
+ <p>
+ Fix erroneous lock check assertion when <c>wx</c> is run
+ on MacOS X.</p>
+ <p>
+ Own Id: OTP-14437 Aux Id: ERL-360 </p>
+ </item>
+ <item>
+ <p>Active-mode TCP sockets are now cleaned up properly on
+ send/shutdown errors.</p>
+ <p>
+ Own Id: OTP-14441 Aux Id: ERL-430 </p>
+ </item>
+ <item>
+ <p>
+ Fix compilation of hipe_mkliterals when the LIBS
+ configure variable had to be set.</p>
+ <p>
+ Own Id: OTP-14447</p>
+ </item>
+ </list>
+ </section>
+
+
+ <section><title>Improvements and New Features</title>
+ <list>
+ <item>
+ <p>
+ Added <c>erlang:garbage_collect/2</c> that takes an
+ option list as the last argument that can be used to
+ control whether a minor or a major garbage collection is
+ to be done. Doing a minor collection only collects terms
+ that have recently died, but is cheaper than a major
+ collection.</p>
+ <p>
+ Own Id: OTP-11695</p>
+ </item>
+ <item>
+ <p>
+ Optimized test for tuples with an atom as first element.</p>
+ <p>
+ Own Id: OTP-12148</p>
+ </item>
+ <item>
+ <p>
+ Erlang literals are no longer copied during process to
+ process messaging.</p>
+ <p>
+ Own Id: OTP-13529</p>
+ </item>
+ <item>
+ <p>Add support in the <c>erl_nif</c> API for asynchronous
+ message notifications when sockets or other file
+ descriptors are ready to accept read or write operations.
+ The following functions have been added:</p> <list>
+ <item><p>enif_select</p></item>
+ <item><p>enif_monitor_process</p></item>
+ <item><p>enif_demonitor_process</p></item>
+ <item><p>enif_compare_monitors</p></item>
+ <item><p>enif_open_resource_type_x</p></item> </list>
+ <p>
+ Own Id: OTP-13684</p>
+ </item>
+ <item>
+ <p>There are two new guard BIFs '<c>floor/1</c>' and
+ '<c>ceil/1</c>'. They both return integers. In the
+ '<c>math</c>' module, there are two new BIFs with the
+ same names that return floating point values.</p>
+ <p>
+ Own Id: OTP-13692</p>
+ </item>
+ <item>
+ <p>
+ Remove deprecated <c>erlang:hash/2</c>.</p>
+ <p>
+ *** POTENTIAL INCOMPATIBILITY ***</p>
+ <p>
+ Own Id: OTP-13827</p>
+ </item>
+ <item>
+ <p>Replaced usage of deprecated symbolic <seealso
+ marker="erts:erlang#type-time_unit"><c>time
+ unit</c></seealso> representations.</p>
+ <p>
+ Own Id: OTP-13831 Aux Id: OTP-13735 </p>
+ </item>
+ <item>
+ <p>
+ Added support in zlib for extraction of the inflation
+ dictionary.</p>
+ <p>
+ Own Id: OTP-13842</p>
+ </item>
+ <item>
+ <p>
+ The previously used purge strategy has been removed. The
+ optional purge strategy introduced in ERTS version 8.1 is
+ now the only strategy available.</p>
+ <p>
+ The new purge strategy is slightly incompatible with the
+ old strategy. Previously processes holding <c>fun</c>s
+ that referred to the module being purged either failed a
+ soft purge, or was killed during a hard purge. The new
+ strategy completely ignores <c>fun</c>s. If <c>fun</c>s
+ referring to the code being purged exist, and are used
+ after a purge, an exception will be raised upon usage.
+ That is, the behavior will be exactly the same as the
+ case when a <c>fun</c> is received by a process after the
+ purge.</p>
+ <p>
+ For more information see the documentation of <seealso
+ marker="erts:erlang#check_process_code/3"><c>erlang:check_process_code/3</c></seealso>.</p>
+ <p>
+ *** POTENTIAL INCOMPATIBILITY ***</p>
+ <p>
+ Own Id: OTP-13844 Aux Id: OTP-13833 </p>
+ </item>
+ <item>
+ <p>
+ Dirty schedulers are now enabled by default when the
+ runtime system is built with SMP support.</p>
+ <p>
+ Own Id: OTP-13860</p>
+ </item>
+ <item>
+ <p>
+ Improved ETS lookup/insert/delete speed for large
+ <c>set</c>, <c>bag</c> and <c>duplicate_bag</c> by a
+ significant reduction of the hash load factor. This speed
+ improvement comes at the expense of less than one word
+ per table entry. Tables with less than 256 entries are
+ not affected at all.</p>
+ <p>
+ Own Id: OTP-13903</p>
+ </item>
+ <item>
+ <p>
+ The NIF library <c>reload</c> feature is not supported
+ anymore. It has been marked as deprecated since OTP R15B.
+ This means that you are only allowed to do one successful
+ call to <c>erlang:load_nif/2</c> for each module
+ instance. A second call to <c>erlang:load_nif/2</c> will
+ return <c>{error, {reload, _}}</c> even if the NIF
+ library implements the <c>reload</c> callback.</p>
+ <p>
+ Runtime upgrade of a NIF library is still supported by
+ using the Erlang module upgrade mechanics with a current
+ and an old module instance existing at the same time with
+ their corresponding NIF libraries.</p>
+ <p>
+ *** POTENTIAL INCOMPATIBILITY ***</p>
+ <p>
+ Own Id: OTP-13908</p>
+ </item>
+ <item>
+ <p>
+ Add <c>erlang:system_info(atom_count)</c> and
+ <c>erlang:system_info(atom_limit)</c> to provide a way to
+ retrieve the current and maximum number of atoms.</p>
+ <p>
+ Own Id: OTP-13976</p>
+ </item>
+ <item>
+ <p>The function <c>fmod/2</c> has been added to the
+ <c>math</c> module.</p>
+ <p>
+ Own Id: OTP-14000</p>
+ </item>
+ <item>
+ <p>
+ <c>erlang:load_nif/2</c> returns new error type
+ <c>notsup</c> when called for a HiPE compiled module,
+ which is not supported.</p>
+ <p>
+ Own Id: OTP-14002</p>
+ </item>
+ <item>
+ <p>
+ Add driver and nif lock instrumentation to lcnt</p>
+ <p>
+ Own Id: OTP-14069</p>
+ </item>
+ <item>
+ <p>
+ Reduce memory pressure by converting sub-binaries to
+ heap-binaries when possible. This is done during garbage
+ collection.</p>
+ <p>
+ Own Id: OTP-14149</p>
+ </item>
+ <item>
+ <p>
+ Dirty schedulers are now enabled and supported on Erlang
+ runtime systems with SMP support.</p>
+ <p>
+ Besides support for dirty NIFs also support for dirty
+ BIFs and dirty garbage collection have been introduced.
+ All garbage collections that potentially will take a long
+ time to complete are now performed on dirty schedulers if
+ enabled.</p>
+ <p>
+ <seealso
+ marker="erts:erlang#statistics/1"><c>erlang:statistics/1</c></seealso>
+ with arguments inspecting scheduler and run queue states
+ have been changed due to the dirty scheduler support.
+ Code using this functionality may have to be rewritten
+ taking these incompatibilities into consideration.
+ Examples of such uses are calls to <seealso
+ marker="erts:erlang#statistics_scheduler_wall_time"><c>erlang:statistics(scheduler_wall_time)</c></seealso>,
+ <seealso
+ marker="erts:erlang#statistics_total_run_queue_lengths"><c>statistics(total_run_queue_lengths)</c></seealso>,
+ <seealso
+ marker="erts:erlang#statistics_total_active_tasks"><c>statistics(total_active_tasks)</c></seealso>,
+ etc.</p>
+ <p>
+ *** POTENTIAL INCOMPATIBILITY ***</p>
+ <p>
+ Own Id: OTP-14152</p>
+ </item>
+ <item>
+ <p>Atoms may now contain arbitrary Unicode
+ characters.</p>
+ <p>
+ Own Id: OTP-14178</p>
+ </item>
+ <item>
+ <p>
+ Introduce an event manager in Erlang to handle OS
+ signals. A subset of OS signals may be subscribed to and
+ those are described in the Kernel application.</p>
+ <p>
+ Own Id: OTP-14186</p>
+ </item>
+ <item>
+ <p>
+ The <c>escript</c> program now handles symbolic links to
+ escripts.</p>
+ <p>
+ This is useful for standalone systems with
+ <c>escript</c>s residing on a bin directory not included
+ in the execution path (as it may cause their <c>erl</c>
+ program(s) to override the desired one). Instead the
+ <c>escript</c>s can be referred to via symbolic links
+ from a bin directory in the path.</p>
+ <p>
+ Own Id: OTP-14201 Aux Id: PR-1293 </p>
+ </item>
+ <item>
+ <p>
+ All uses of the magic binary kludge has been replaced by
+ uses of erlang references.</p>
+ <p>
+ A magic binary was presented as an empty binary, but
+ actually referred other data internally in the Erlang VM.
+ Since they were presented as empty binaries, different
+ magic binaries compared as equal, and also lost their
+ internal data when passed out of an erlang node.</p>
+ <p>
+ The new usage of references has not got any of these
+ strange semantic issues, and the usage of these
+ references has been optimized to give the same
+ performance benefits as well as memory usage benefits as
+ magic binaries had.</p>
+ <p>
+ A couple of examples of previous uses of magic binaries
+ are match specifications and NIF resources.</p>
+ <p>
+ Own Id: OTP-14205</p>
+ </item>
+ <item>
+ <p>
+ The non-smp emulators have been deprecated and are
+ scheduled for removal in OTP-21.</p>
+ <p>
+ In preparation for this, the threaded non-smp emulator is
+ no longer built by default and has to be enabled using
+ the --enable-plain-emulator to configure.</p>
+ <p>
+ *** POTENTIAL INCOMPATIBILITY ***</p>
+ <p>
+ Own Id: OTP-14272</p>
+ </item>
+ <item>
+ <p>
+ Allow HiPE to run on VM built with
+ <c>--enable-m32-build</c>.</p>
+ <p>
+ Own Id: OTP-14330 Aux Id: PR-1397 </p>
+ </item>
+ <item>
+ <p>
+ Upgraded the OTP internal PCRE library from version 8.33
+ to version 8.40. This library is used for implementation
+ of the <seealso marker="stdlib:re"><c>re</c></seealso>
+ regular expressions module.</p>
+ <p>
+ Besides various bug fixes, the new version allows for
+ better stack protection. In order to utilize this
+ feature, the stack size of normal scheduler threads is
+ now by default set to 128 kilo words on all platforms.
+ The stack size of normal scheduler threads can be set
+ upon system start by passing the <seealso
+ marker="erts:erl#sched_thread_stack_size"><c>+sss</c></seealso>
+ command line argument to the <seealso
+ marker="erts:erl"><c>erl</c></seealso> command.</p>
+ <p>
+ See <url
+ href="http://pcre.org/original/changelog.txt">http://pcre.org/original/changelog.txt</url>
+ for information about changes made to PCRE between the
+ versions 8.33 and 8.40.</p>
+ <p>
+ *** POTENTIAL INCOMPATIBILITY ***</p>
+ <p>
+ Own Id: OTP-14331 Aux Id: ERL-208 </p>
+ </item>
+ <item>
+ <p>
+ Remove generation of atoms in old latin1 external format
+ in the distribution between erlang nodes,
+ <c>erl_interface</c>, and <c>jinterface</c>. The new utf8
+ format for atoms was introduced in OTP R16. An OTP 20
+ node can therefore not connect to nodes older than R16.</p>
+ <p>
+ Atoms that can be encoded using latin1 are still encoded
+ by <c>term_to_binary()</c> using latin1 encoding. Note
+ that all atoms will by default be encoded using utf8 in a
+ future Erlang/OTP release. For more information see the
+ documentation of <seealso
+ marker="erts:erlang#term_to_binary/2"><c>erlang:term_to_binary/2</c></seealso>.</p>
+ <p>
+ Own Id: OTP-14337</p>
+ </item>
+ <item>
+ <p>
+ Added function <c>re:version/0</c> which returns
+ information about the OTP internal PCRE version used for
+ implementation of the <c>re</c> module.</p>
+ <p>
+ Own Id: OTP-14347 Aux Id: PR-1412 </p>
+ </item>
+ <item>
+ <p>
+ Added new debug bif <c>erlang:list_to_port/1</c>.</p>
+ <p>
+ Own Id: OTP-14348</p>
+ </item>
+ <item>
+ <p>
+ Various improvements of timer management internally in
+ the VM. These improvements both reduced memory
+ consumption of timer wheels as well as reduce the amount
+ of work that has to be performed in order to handle
+ timers.</p>
+ <p>
+ Own Id: OTP-14356</p>
+ </item>
+ <item>
+ <p> Sockets can now be bound to device (SO_BINDTODEVICE)
+ on platforms where it is supported. </p> <p> This has
+ been implemented e.g to support VRF-Lite under Linux; see
+ <url
+ href="https://www.kernel.org/doc/Documentation/networking/vrf.txt">
+ VRF </url>, and GitHub pull request <url
+ href="https://github.com/erlang/otp/pull/1326">#1326</url>.
+ </p>
+ <p>
+ Own Id: OTP-14357 Aux Id: PR-1326 </p>
+ </item>
+ <item>
+ <p>Added the following <seealso
+ marker="erl"><c>erl</c></seealso> command line arguments
+ with which you can set suggested stack for dirty
+ schedulers:</p> <taglist> <tag><seealso
+ marker="erl#dcpu_sched_thread_stack_size"><c>+sssdcpu</c></seealso></tag>
+ <item><p>for dirty CPU schedulers</p></item>
+ <tag><seealso
+ marker="erl#dio_sched_thread_stack_size"><c>+sssdio</c></seealso></tag>
+ <item><p>for dirty IO schedulers</p></item> </taglist>
+ <p>The default suggested stack size for dirty schedulers
+ is 40 kilo words.</p>
+ <p>
+ Own Id: OTP-14380</p>
+ </item>
+ <item>
+ <p>
+ Changed erts startup program name, argv 0, to use the
+ environment variable <c>ESCRIPT_NAME</c> so that
+ <c>erlc</c>, <c>dialyzer</c>, <c>typer</c>,
+ <c>ct_run</c>, or the escript name can be seen with
+ external programs, such as ps and htop (depending on
+ options), on unix.</p>
+ <p>
+ Own Id: OTP-14381</p>
+ </item>
+ <item>
+ <p>
+ Improvements of <c>escript</c> documentation.</p>
+ <p>
+ Own Id: OTP-14384 Aux Id: OTP-14201 </p>
+ </item>
+ <item>
+ <p>
+ Add function <c>enif_hash</c> for NIFs to calculate hash
+ values of arbitrary terms.</p>
+ <p>
+ Own Id: OTP-14385 Aux Id: PR-1413 </p>
+ </item>
+ <item>
+ <p>'<c>./configure --enable-lock-counter</c>' will
+ enabling building of an additional emulator that has
+ support for lock counting. (The option previously
+ existed, but would turn on lock counting in the default
+ emulator being built.) To start the lock-counting
+ emulator, use '<c>erl -emu_type lcnt</c>'.</p>
+ <p>On Windows, <c>erl</c> recognized the undocumented
+ option <c>-debug</c> for starting a debug-compiled
+ emulator. That option has been removed. Use '<c>erl
+ -emu_type debug</c>' instead.</p>
+ <p>
+ Own Id: OTP-14407</p>
+ </item>
+ <item>
+ <p>
+ Warnings have been added to the relevant documentation
+ about not using un-secure distributed nodes in exposed
+ environments.</p>
+ <p>
+ Own Id: OTP-14425</p>
+ </item>
+ <item>
+ <p>
+ Improvement of the documentation of the environment
+ variable <c>ERL_CRASH_DUMP_SECONDS</c> as well as the
+ default behavior when it is not set.</p>
+ <p>
+ Own Id: OTP-14434</p>
+ </item>
+ <item>
+ <p>
+ Enabled off-heap message queue for some system processes
+ that might receive large amounts of messages.</p>
+ <p>
+ Own Id: OTP-14438</p>
+ </item>
+ <item>
+ <p>ETS lock indexes have been replaced with the table
+ name in LCNT results.</p>
+ <p>
+ Own Id: OTP-14442 Aux Id: ERIERL-22 </p>
+ </item>
+ <item>
+ <p>
+ Introduced the new functions <seealso
+ marker="erl_nif#enif_whereis_pid"><c>enif_whereis_pid()</c></seealso>
+ and <seealso
+ marker="erl_nif#enif_whereis_port"><c>enif_whereis_port()</c></seealso>.</p>
+ <p>
+ Own Id: OTP-14453 Aux Id: PR-1400 </p>
+ </item>
+ </list>
+ </section>
+
+</section>
+
+<section><title>Erts 8.3.5.6</title>
+
+ <section><title>Fixed Bugs and Malfunctions</title>
+ <list>
+ <item>
+ <p>
+ Fixed small memory leak that could occur when sending to
+ a terminating port.</p>
+ <p>
+ Own Id: OTP-14609 Aux Id: ERIERL-238 </p>
+ </item>
+ </list>
+ </section>
+
+</section>
+
+<section><title>Erts 8.3.5.5</title>
+
+ <section><title>Fixed Bugs and Malfunctions</title>
+ <list>
+ <item>
+ <p>Fixed a race condition in the inet driver that could
+ cause receive to hang when the emulator was compiled with
+ gcc 8.</p>
+ <p>
+ Own Id: OTP-15158 Aux Id: ERL-654 </p>
+ </item>
+ <item>
+ <p>
+ Fixed a bug causing some Erlang references to be
+ inconsistently ordered. This could for example cause
+ failure to look up certain elements with references as
+ keys in search data structures. This bug was introduced
+ in R13B02.</p>
+ <p>
+ Thanks to Simon Cornish for finding the bug and supplying
+ a fix.</p>
+ <p>
+ *** POTENTIAL INCOMPATIBILITY ***</p>
+ <p>
+ Own Id: OTP-15225</p>
+ </item>
+ </list>
+ </section>
+
+</section>
+
+<section><title>Erts 8.3.5.4</title>
+
+ <section><title>Fixed Bugs and Malfunctions</title>
+ <list>
+ <item>
+ <p>Fixed a bug in file closure on Unix; close(2) was
+ retried on EINTR which could cause a different (recently
+ opened) file to be closed as well.</p>
+ <p>
+ Own Id: OTP-14775</p>
+ </item>
+ <item>
+ <p>
+ A race-condition when tearing down a connection with
+ active node monitors could cause the runtime system to
+ crash.</p>
+ <p>
+ This bug was introduced in ERTS version 8.0 (OTP 19.0).</p>
+ <p>
+ Own Id: OTP-14781 Aux Id: OTP-13047 </p>
+ </item>
+ </list>
+ </section>
+
+</section>
+
+<section><title>Erts 8.3.5.3</title>
+
+ <section><title>Fixed Bugs and Malfunctions</title>
+ <list>
+ <item>
+ <p>
+ A timer internal bit-field used for storing scheduler id
+ was too small. As a result, VM internal timer data
+ structures could become inconsistent when using 1024
+ schedulers on the system. Note that systems with less
+ than 1024 schedulers are not effected by this bug.</p>
+ <p>
+ This bug was introduced in ERTS version 7.0 (OTP 18.0).</p>
+ <p>
+ Own Id: OTP-14548 Aux Id: OTP-11997, ERL-468 </p>
+ </item>
+ <item>
+ <p>
+ Fixed bug in <c>binary_to_term</c> and
+ <c>binary_to_atom</c> that could cause VM crash.
+ Typically happens when the last character of an UTF8
+ string is in the range 128 to 255, but truncated to only
+ one byte. Bug exists in <c>binary_to_term</c> since ERTS
+ version 5.10.2 (OTP_R16B01) and <c>binary_to_atom</c>
+ since ERTS version 9.0 (OTP-20.0).</p>
+ <p>
+ Own Id: OTP-14590 Aux Id: ERL-474 </p>
+ </item>
+ <item>
+ <p>
+ Fix bug causing VM crash when a module with
+ <c>-on_load</c> directive is loaded while
+ <c>erlang:trace(on_load, ...)</c> is enabled.</p>
+ <p>
+ Own Id: OTP-14612</p>
+ </item>
+ <item>
+ <p>
+ Fixed bug that could cause a VM crash when a corrupt
+ message is received on distribution channel from other
+ node.</p>
+ <p>
+ Own Id: OTP-14661 Aux Id: ERIERL-80 </p>
+ </item>
+ </list>
+ </section>
+
+</section>
+
+<section><title>Erts 8.3.5.2</title>
+
+ <section><title>Fixed Bugs and Malfunctions</title>
+ <list>
+ <item>
+ <p>
+ Fix performance bug in pre-allocators that could cause
+ them to permanently fall back on normal more expensive
+ memory allocation. Pre-allocators are used for quick
+ allocation of short lived meta data used by messages and
+ other scheduled tasks. Bug exists since OTP_R15B02.</p>
+ <p>
+ Own Id: OTP-14491</p>
+ </item>
+ <item>
+ <p>Fixed a bug that prevented TCP sockets from being
+ closed properly on send timeouts.</p>
+ <p>
+ Own Id: OTP-14509</p>
+ </item>
+ <item>
+ <p>
+ Fixed bug in operator <c>bxor</c> causing erroneuos
+ result when one operand is a big <em>negative</em>
+ integer with the lowest <c>N*W</c> bits as zero and the
+ other operand not larger than <c>N*W</c> bits. <c>N</c>
+ is an integer of 1 or larger and <c>W</c> is 32 or 64
+ depending on word size.</p>
+ <p>
+ Own Id: OTP-14514</p>
+ </item>
+ </list>
+ </section>
+
+</section>
+
+<section><title>Erts 8.3.5.1</title>
+ <section><title>Fixed Bugs and Malfunctions</title>
+ <list>
+ <item>
+ <p>
+ Fixed a bug in gen_tcp:send where it never returned when
+ repeatedly called on a remotely closed TCP socket.</p>
+ <p>
+ Own Id: OTP-13939 Aux Id: ERL-193 </p>
+ </item>
+ <item>
+ <p>
+ Fixed segfault that could happen during cleanup of
+ aborted erlang:port_command/3 calls. A port_command is
+ aborted if the port is closed at the same time as the
+ port_command was issued. This bug was introduced in
+ erts-8.0.</p>
+ <p>
+ Own Id: OTP-14481</p>
+ </item>
+ <item>
+ <p>
+ Fixed implementation of <c>statistics(wall_clock)</c> and
+ <c>statistics(runtime)</c> so that values do not
+ unnecessarily wrap due to the emulator. Note that the
+ values returned by <c>statistics(runtime)</c> may still
+ wrap due to limitations in the underlying functionality
+ provided by the operating system.</p>
+ <p>
+ Own Id: OTP-14484</p>
+ </item>
+ </list>
+ </section>
+
+</section>
+
+<section><title>Erts 8.3.5</title>
+
+ <section><title>Fixed Bugs and Malfunctions</title>
+ <list>
+ <item>
+ <p>Active-mode TCP sockets are now cleaned up properly on
+ send/shutdown errors.</p>
+ <p>
+ Own Id: OTP-14441 Aux Id: ERL-430 </p>
+ </item>
+ <item>
+ <p>
+ A code purge operation could under certain circumstances
+ expand the size of hibernated processes.</p>
+ <p>
+ Own Id: OTP-14444 Aux Id: ERIERL-24 </p>
+ </item>
+ <item>
+ <p>
+ Fix so that the ERL_ZZ_SIGTERM_KILL introduced in
+ erts-8.3.4 works.</p>
+ <p>
+ Own Id: OTP-14451</p>
+ </item>
+ </list>
+ </section>
+
+</section>
+
+<section><title>Erts 8.3.4</title>
+
+ <section><title>Fixed Bugs and Malfunctions</title>
+ <list>
+ <item>
+ <p>
+ Add option to make SIGTERM trigger the OS default
+ behaviour instead of doing a gracefull shutdown. To
+ activate this bahviour the environment variable
+ ERL_ZZ_SIGTERM_KILL should be set to "true". This option
+ only works in OTP 19 as OTP 20 will have a different way
+ to deal with SIGTERM.</p>
+ <p>
+ Own Id: OTP-14418 Aux Id: ERIERL-15 </p>
+ </item>
+ </list>
+ </section>
+
+</section>
+
+<section><title>Erts 8.3.3</title>
+
+ <section><title>Fixed Bugs and Malfunctions</title>
+ <list>
+ <item>
+ <p>
+ Fixed memory segment cache used for multiblock carriers.
+ Huge (> 2GB) memory segments could cause a VM crash.
+ Creation of such huge memory segments used for multiblock
+ carriers is however very uncommon.</p>
+ <p>
+ Own Id: OTP-14360 Aux Id: ERL-401, PR-1417 </p>
+ </item>
+ <item>
+ <p>
+ Fix release note for OTP-14290 in ERTS version 8.3.1. It
+ was erroneously placed under "Known Bugs and Problems".</p>
+ <p>
+ Own Id: OTP-14363 Aux Id: OTP-14290 </p>
+ </item>
+ </list>
+ </section>
+
+</section>
+
+<section><title>Erts 8.3.2</title>
+
+ <section><title>Fixed Bugs and Malfunctions</title>
+ <list>
+ <item>
+ <p>
+ The <c>+Bi</c> command line argument of <c>erl</c>
+ erroneously caused <c>SIGTERM</c> to be ignored by the VM
+ as well as of all its child processes. This bug was
+ introduced in erts version 8.3.</p>
+ <p>
+ Own Id: OTP-14358 Aux Id: OTP-14085 </p>
+ </item>
+ </list>
+ </section>
+
+</section>
+
+<section><title>Erts 8.3.1</title>
+
+ <section><title>Fixed Bugs and Malfunctions</title>
+ <list>
+ <item>
+ <p>
+ Invoking <c>init:stop/0</c> via the SIGTERM signal, in a
+ non-SMP BEAM, could cause BEAM to terminate with fatal
+ error. This has now been fixed and the BEAM will
+ terminate normally when SIGTERM is received.</p>
+ <p>
+ Own Id: OTP-14290</p>
+ </item>
+ <item>
+ <p>
+ Trying to open a directory with file:read_file/1 on Unix
+ leaked a file descriptor. This bug has now been fixed.</p>
+ <p>
+ Own Id: OTP-14308 Aux Id: ERL-383 </p>
+ </item>
+ </list>
+ </section>
+
+</section>
+
+<section><title>Erts 8.3</title>
+
+ <section><title>Fixed Bugs and Malfunctions</title>
+ <list>
+ <item>
+ <p>Fixed a number of bugs that caused faulty stack-traces
+ to be generated. The faulty stack traces were generated
+ either when applying the following functions or tracing
+ the following functions:</p> <list>
+ <item><c>erlang:error/1</c></item>
+ <item><c>erlang:error/2</c></item>
+ <item><c>erlang:exit/1</c></item>
+ <item><c>erlang:throw/1</c></item> </list>
+ <p>
+ Own Id: OTP-14055</p>
+ </item>
+ <item>
+ <p>
+ Corrected documentation about memory footprint for maps.</p>
+ <p>
+ Own Id: OTP-14118</p>
+ </item>
+ <item>
+ <p>
+ Fix <c>process_info(Pid, current_stacktrace)</c> to use
+ stack depth limit set by
+ <c>system_flag(backtrace_depth)</c>. The old behavior was
+ a hard coded depth limit of 8.</p>
+ <p>
+ Own Id: OTP-14119 Aux Id: PR-1263 </p>
+ </item>
+ <item>
+ <p>
+ A process calling <seealso
+ marker="erlang#system_flag_multi_scheduling"><c>erlang:system_flag(multi_scheduling,
+ block)</c></seealso> could end up hanging forever in the
+ call.</p>
+ <p>
+ Own Id: OTP-14121</p>
+ </item>
+ <item>
+ <p>Dirty scheduler bug fixes:</p> <list> <item><p>Fixed
+ call time tracing of process being scheduled on dirty
+ scheduler.</p></item> <item><p>GC info from dirty
+ schedulers.</p></item> <item><p>Multi scheduling block
+ with dirty schedulers could crash the runtime
+ system.</p></item> <item><p>Process structures could be
+ removed prematurely.</p></item> <item><p>GC on dirty
+ scheduler could crash the runtime system.</p></item>
+ <item><p>Termination of a process executing on a dirty
+ scheduler could cause a runtime system crash.</p></item>
+ </list>
+ <p>
+ Own Id: OTP-14122</p>
+ </item>
+ <item>
+ <p>
+ Fixed crash that occurred when writing timer data to a
+ crash dump.</p>
+ <p>
+ Own Id: OTP-14133</p>
+ </item>
+ <item>
+ <p>
+ A literal area could be removed while still referred from
+ processes.</p>
+ <p>
+ Own Id: OTP-14134</p>
+ </item>
+ <item>
+ <p>
+ Fixed a bug in the garbage collector that could crash the
+ runtime system.</p>
+ <p>
+ Own Id: OTP-14135</p>
+ </item>
+ <item>
+ <p>
+ Fixed a bug in call-time trace for NIFs which caused
+ tracing to erroneously be started multiple times for one
+ call.</p>
+ <p>
+ Own Id: OTP-14136</p>
+ </item>
+ <item>
+ <p>
+ Remove a debug printout and an unnecessary garbage
+ collection when handling exceptions in hipe compiled
+ code.</p>
+ <p>
+ Own Id: OTP-14153</p>
+ </item>
+ <item>
+ <p>
+ Fix bug in tracing of garbage collection that could cause
+ VM crash. Bug exists since OTP 19.0.</p>
+ <p>
+ Own Id: OTP-14154</p>
+ </item>
+ <item>
+ <p>
+ Fix bug in <c>binary_to_term</c> for binaries created by
+ <c>term_to_binary </c> with option <c>compressed</c>. The
+ bug can cause <c>badarg</c> exception for a valid binary
+ when Erlang VM is linked against a <c>zlib</c> library of
+ version 1.2.9 or newer. Bug exists since OTP 17.0.</p>
+ <p>
+ Own Id: OTP-14159 Aux Id: ERL-340 </p>
+ </item>
+ <item>
+ <p>
+ Fix suspension of schedulers when generating a crashdump.</p>
+ <p>
+ Own Id: OTP-14164</p>
+ </item>
+ <item>
+ <p>NIF resources was not handled in a thread-safe manner
+ in the runtime system without SMP support.</p>
+ <p>As a consequence of this fix, the following driver
+ functions are now thread-safe also in the runtime system
+ without SMP support:</p> <list>
+ <item><p><c>driver_free_binary()</c></p></item>
+ <item><p><c>driver_realloc_binary()</c></p></item>
+ <item><p><c>driver_binary_get_refc()</c></p></item>
+ <item><p><c>driver_binary_inc_refc()</c></p></item>
+ <item><p><c>driver_binary_dec_refc()</c></p></item>
+ </list>
+ <p>
+ Own Id: OTP-14202</p>
+ </item>
+ <item>
+ <p>
+ Fix <c>erlang:round/1</c> for large floating point
+ numbers with an odd absolute value between <c>(1 bsl
+ 52)</c> and <c>(1 bsl 53)</c>. The result was falsely
+ calculated as the next higher even number even though all
+ integer values up to <c>(1 bsl 53)</c> can be represented
+ as floats with full precision.</p>
+ <p>
+ Own Id: OTP-14227</p>
+ </item>
+ <item>
+ <p>
+ Add size of literals to module code size in crash dump
+ and <c>(l)oaded</c> command in break menu like it used to
+ be before OTP-19.0.</p>
+ <p>
+ Own Id: OTP-14228</p>
+ </item>
+ <item>
+ <p>
+ Fix potential bug in <c>enif_send</c> when called without
+ a process context and with argument <c>msg_env</c> as
+ <c>NULL</c>.</p>
+ <p>
+ Own Id: OTP-14229</p>
+ </item>
+ <item>
+ <p>
+ Fix bug where passing an appendable binary to
+ <c>erlang:port_control()</c> could crash the emulator.</p>
+ <p>
+ Own Id: OTP-14231</p>
+ </item>
+ <item>
+ <p>
+ Receive expressions with timeout in the Erlang shell
+ could cause a VM crash.</p>
+ <p>
+ Own Id: OTP-14241 Aux Id: ERL-365 </p>
+ </item>
+ </list>
+ </section>
+
+
+ <section><title>Improvements and New Features</title>
+ <list>
+ <item>
+ <p>
+ A received SIGTERM signal to beam will generate a
+ <c>'stop'</c> message to the <c>init</c> process and
+ terminate the Erlang VM nicely. This is equivalent to
+ calling <c>init:stop/0</c>.</p>
+ <p>
+ Own Id: OTP-14085</p>
+ </item>
+ <item>
+ <p>
+ Workaround for buggy Android implementation of
+ <c>PTHREAD_STACK_MIN</c> causing build of runtime system
+ to crash on undeclared <c>PAGE_SIZE</c>.</p>
+ <p>
+ Own Id: OTP-14165 Aux Id: ERL-319 </p>
+ </item>
+ <item>
+ <p>
+ Add configure option --without-thread-names that removes
+ the naming of individual emulator threads.</p>
+ <p>
+ Own Id: OTP-14234</p>
+ </item>
+ <item>
+ <p>
+ Add warning in documentation of <c>zlib:deflateInit/6</c>
+ about option <c>WindowsBits</c> values 8 and -8.</p>
+ <p>
+ Own Id: OTP-14254 Aux Id: ERL-362 </p>
+ </item>
+ </list>
+ </section>
+
+</section>
+
+<section><title>Erts 8.2.2</title>
+
+ <section><title>Fixed Bugs and Malfunctions</title>
+ <list>
+ <item>
+ <p>
+ Fix bug in <c>binary_to_term</c> for binaries created by
+ <c>term_to_binary </c> with option <c>compressed</c>. The
+ bug can cause <c>badarg</c> exception for a valid binary
+ when Erlang VM is linked against a <c>zlib</c> library of
+ version 1.2.9 or newer. Bug exists since OTP 17.0.</p>
+ <p>
+ Own Id: OTP-14159 Aux Id: ERL-340 </p>
+ </item>
+ <item>
+ <p>
+ The driver efile_drv when opening a file now use fstat()
+ on the open file instead of stat() before opening, if
+ fstat() exists. This avoids a race when the file happens
+ to change between stat() and open().</p>
+ <p>
+ Own Id: OTP-14184 Aux Id: seq-13266 </p>
+ </item>
+ </list>
+ </section>
+
+</section>
+
+<section><title>Erts 8.2.1</title>
+ <section><title>Fixed Bugs and Malfunctions</title>
+ <list>
+ <item>
+ <p>
+ Fix a quite rare bug causing VM crash during code loading
+ and the use of export funs (fun M:F/A) of not yet loaded
+ modules. Requires a very specfic timing of concurrent
+ scheduler threads. Has been seen on ARM but can probably
+ also occure on other architectures. Bug has existed since
+ OTP R16.</p>
+ <p>
+ Own Id: OTP-14144 Aux Id: seq13242 </p>
+ </item>
+ </list>
+ </section>
+
+</section>
+
+<section><title>Erts 8.2</title>
+
+ <section><title>Fixed Bugs and Malfunctions</title>
+ <list>
+ <item>
+ <p>
+ Fixed <c>configure</c> failures on MacOSX. Most important
+ <c>clock_gettime()</c> was detected when building for
+ MacOSX - El Capitan using XCode 8 despite it is not
+ available until MacOSX - Sierra.</p>
+ <p>
+ Own Id: OTP-13904 Aux Id: ERL-256 </p>
+ </item>
+ <item>
+ <p>
+ <c>code:add_pathsa/1</c> and command line option
+ <c>-pa</c> both revert the given list of directories when
+ adding it at the beginning of the code path. This is now
+ documented.</p>
+ <p>
+ Own Id: OTP-13920 Aux Id: ERL-267 </p>
+ </item>
+ <item>
+ <p>
+ Fix a compilation error of erts in OpenBSD related to the
+ usage of the __errno variable.</p>
+ <p>
+ Own Id: OTP-13927</p>
+ </item>
+ <item>
+ <p>
+ Fixed so that when enabling tracing on a process that had
+ an invalid tracer associated with it, the new tracer
+ overwrites the old tracer. Before this fix, calling
+ erlang:trace/3 would behave as if the tracer was still
+ alive and not apply the new trace.</p>
+ <p>
+ This fault was introduced in ERTS 8.0.</p>
+ <p>
+ Own Id: OTP-13928</p>
+ </item>
+ <item>
+ <p>
+ Fix parsing of <c>-profile_boot 'true' | 'false'</c></p>
+ <p>
+ Own Id: OTP-13955 Aux Id: ERL-280 </p>
+ </item>
+ <item>
+ <p>
+ A slight improvement of <c>erlang:get_stacktrace/0</c>
+ for exceptions raised in hipe compiled code. Beam
+ compiled functions in such stack trace was earlier
+ replaced by some unrelated function. They are now instead
+ omitted. This is an attempt to reduce the confusion in
+ the absence of a complete and correct stack trace for
+ mixed beam and hipe functions.</p>
+ <p>
+ Own Id: OTP-13992</p>
+ </item>
+ <item>
+ <p> Correct type declaration of match specification head.
+ </p>
+ <p>
+ Own Id: OTP-13996</p>
+ </item>
+ <item>
+ <p>
+ HiPE code loading failed for x86_64 if gcc was configured
+ with <c>--enable-default-pie</c>. Fixed by disabling PIE,
+ if needed for HiPE, when building the VM.</p>
+ <p>
+ Own Id: OTP-14031 Aux Id: ERL-294, PR-1239 </p>
+ </item>
+ <item>
+ <p>
+ Faulty arguments could be presented on exception from a
+ NIF that had rescheduled itself using
+ <c>enif_schedule_nif()</c>.</p>
+ <p>
+ Own Id: OTP-14048</p>
+ </item>
+ <item>
+ <p>
+ The runtime system could crash if a garbage collection on
+ a process was performed immediately after a NIF had been
+ rescheduled using <c>enif_schedule_nif()</c>.</p>
+ <p>
+ Own Id: OTP-14049</p>
+ </item>
+ <item>
+ <p>
+ A reference to purged code could be left undetected by
+ the purge operation if a process just had rescheduled a
+ NIF call using <c>enif_schedule_nif()</c> when the
+ process was checked. This could cause a runtime system
+ crash.</p>
+ <p>
+ Own Id: OTP-14050</p>
+ </item>
+ <item>
+ <p>Fixed a number of dirty scheduler related bugs:</p>
+ <list> <item><p>Process priority was not handled correct
+ when scheduling on a dirty scheduler.</p></item>
+ <item><p>The runtime system could crash when an exit
+ signal with a compound exit reason was sent to a process
+ executing on a dirty scheduler.</p></item> <item><p>The
+ runtime system crashed when call tracing a process
+ executing on a dirty scheduler.</p></item> <item><p>A
+ code purge operation could end up hanging forever when a
+ process executed on a dirty scheduler</p></item> </list>
+ <p>
+ Own Id: OTP-14051</p>
+ </item>
+ </list>
+ </section>
+
+
+ <section><title>Improvements and New Features</title>
+ <list>
+ <item>
+ <p>
+ Fix minor soft purge race bug that could incorrectly
+ trigger code_server to load new code for the module if
+ the soft purge failed and no current version of the
+ module existed.</p>
+ <p>
+ Own Id: OTP-13925</p>
+ </item>
+ <item>
+ <p>
+ To ease troubleshooting, <c>erlang:load_nif/2</c> now
+ includes the return value from a failed call to
+ load/reload/upgrade in the text part of the error tuple.
+ The <c>crypto</c> NIF makes use of this feature by
+ returning the source line where/if the initialization
+ fails.</p>
+ <p>
+ Own Id: OTP-13951</p>
+ </item>
+ <item>
+ <p>
+ New environment variable <c>ERL_CRASH_DUMP_BYTES</c> can
+ be used to limit the size of crash dumps. If the limit is
+ reached, crash dump generation is aborted and the
+ generated file will be truncated.</p>
+ <p>
+ Own Id: OTP-14046</p>
+ </item>
+ </list>
+ </section>
+
+</section>
+
+<section><title>Erts 8.1.1.1</title>
+
+ <section><title>Fixed Bugs and Malfunctions</title>
+ <list>
+ <item>
+ <p>
+ A code purge operation could under certain circumstances
+ expand the size of hibernated processes.</p>
+ <p>
+ Own Id: OTP-14444 Aux Id: ERIERL-24 </p>
+ </item>
+ </list>
+ </section>
+
+</section>
+
+<section><title>Erts 8.1.1</title>
+
+ <section><title>Fixed Bugs and Malfunctions</title>
+ <list>
+ <item>
+ <p>
+ The emulator got a dynamic library dependency towards
+ libsctp, which on Linux was not intended since the
+ emulator there loads and resolves the needed sctp
+ functions in runtime. This has been fixed and a configure
+ switch --enable-sctp=lib has been added for those who
+ want such a library dependency.</p>
+ <p>
+ Own Id: OTP-13956 Aux Id: ERL-262, ERL-133 </p>
+ </item>
+ <item>
+ <p>
+ Fix SIGUSR1 crashdump generation</p>
+ <p>
+ Do not generate a core when a crashdump is asked for.</p>
+ <p>
+ Own Id: OTP-13997</p>
+ </item>
+ <item>
+ <p>The new functions in <c>code</c> that allows loading
+ of many modules at once had a performance problem. While
+ executing a helper function in the <c>erl_prim_loader</c>
+ process, garbage messages were produced. The garbages
+ messages were ignored and ultimately discarded, but there
+ would be a negative impact on performance and memory
+ usage. The number of garbage message depended on both the
+ number of modules to be loaded and the length of the code
+ path.</p>
+ <p>The functions affected of this problem were:
+ <c>atomic_load/1</c>, <c>ensure_modules_loaded/1</c>, and
+ <c>prepare_loading/1</c>.</p>
+ <p>
+ Own Id: OTP-14009</p>
+ </item>
+ </list>
+ </section>
+
+</section>
<section><title>Erts 8.1</title>
@@ -320,7 +4217,7 @@
<list>
<item>
<p>
- Fixed a VM crash that occured in a garbage collection of
+ Fixed a VM crash that occurred in a garbage collection of
a process when it had received binaries. This bug was
introduced in ERTS version 8.0 (OTP 19.0).</p>
<p>
@@ -337,7 +4234,7 @@
<list>
<item>
<p>
- Fixed a VM crash that occured in garbage collection of a
+ Fixed a VM crash that occurred in garbage collection of a
process when it had received maps over the distribution.
This bug was introduced in ERTS version 8.0 (OTP 19.0).</p>
<p>
@@ -1148,6 +5045,179 @@
</section>
+<section><title>Erts 7.3.1.6</title>
+
+ <section><title>Improvements and New Features</title>
+ <list>
+ <item>
+ <p>List subtraction (The <c>--</c> operator) will now
+ yield properly on large inputs.</p>
+ <p>
+ Own Id: OTP-15371</p>
+ </item>
+ </list>
+ </section>
+
+</section>
+
+<section><title>Erts 7.3.1.5</title>
+
+ <section><title>Fixed Bugs and Malfunctions</title>
+ <list>
+ <item>
+ <p>
+ Fixed small memory leak that could occur when sending to
+ a terminating port.</p>
+ <p>
+ Own Id: OTP-14609 Aux Id: ERIERL-238 </p>
+ </item>
+ </list>
+ </section>
+
+</section>
+
+<section><title>Erts 7.3.1.4</title>
+ <section><title>Fixed Bugs and Malfunctions</title>
+ <list>
+ <item>
+ <p>
+ Fix performance bug in pre-allocators that could cause
+ them to permanently fall back on normal more expensive
+ memory allocation. Pre-allocators are used for quick
+ allocation of short lived meta data used by messages and
+ other scheduled tasks. Bug exists since OTP_R15B02.</p>
+ <p>
+ Own Id: OTP-14491</p>
+ </item>
+ <item>
+ <p>
+ Fixed bug in operator <c>bxor</c> causing erroneuos
+ result when one operand is a big <em>negative</em>
+ integer with the lowest <c>N*W</c> bits as zero and the
+ other operand not larger than <c>N*W</c> bits. <c>N</c>
+ is an integer of 1 or larger and <c>W</c> is 32 or 64
+ depending on word size.</p>
+ <p>
+ Own Id: OTP-14514</p>
+ </item>
+ <item>
+ <p>
+ A timer internal bit-field used for storing scheduler id
+ was too small. As a result, VM internal timer data
+ structures could become inconsistent when using 1024
+ schedulers on the system. Note that systems with less
+ than 1024 schedulers are not effected by this bug.</p>
+ <p>
+ This bug was introduced in ERTS version 7.0 (OTP 18.0).</p>
+ <p>
+ Own Id: OTP-14548 Aux Id: OTP-11997, ERL-468 </p>
+ </item>
+ <item>
+ <p>
+ Fixed bug in <c>binary_to_term</c> and
+ <c>binary_to_atom</c> that could cause VM crash.
+ Typically happens when the last character of an UTF8
+ string is in the range 128 to 255, but truncated to only
+ one byte. Bug exists in <c>binary_to_term</c> since ERTS
+ version 5.10.2 (OTP_R16B01) and <c>binary_to_atom</c>
+ since ERTS version 9.0 (OTP-20.0).</p>
+ <p>
+ Own Id: OTP-14590 Aux Id: ERL-474 </p>
+ </item>
+ </list>
+ </section>
+</section>
+
+<section><title>Erts 7.3.1.3</title>
+
+ <section><title>Fixed Bugs and Malfunctions</title>
+ <list>
+ <item>
+ <p>
+ A bug has been fixed where if erlang was started +B on a
+ unix platform it would be killed by a SIGUSR2 signal when
+ creating a crash dump.</p>
+ <p>
+ Own Id: OTP-13425 Aux Id: ERL-94 </p>
+ </item>
+ <item>
+ <p>
+ Calls to <c>erl_drv_send_term()</c> or
+ <c>erl_drv_output_term()</c> from a non-scheduler thread
+ while the corresponding port was invalid caused the
+ emulator to enter an inconsistent state which eventually
+ caused an emulator crash.</p>
+ <p>
+ Own Id: OTP-13866</p>
+ </item>
+ <item>
+ <p>Driver and NIF operations accessing processes or ports
+ could cause an emulator crash when used from
+ non-scheduler threads. Those operations are:</p> <list>
+ <item><c>erl_drv_send_term()</c></item>
+ <item><c>driver_send_term()</c></item>
+ <item><c>erl_drv_output_term()</c></item>
+ <item><c>driver_output_term()</c></item>
+ <item><c>enif_send()</c></item>
+ <item><c>enif_port_command()</c></item> </list>
+ <p>
+ Own Id: OTP-13869</p>
+ </item>
+ <item>
+ <p>
+ Fix bug in <c>binary_to_term</c> for binaries created by
+ <c>term_to_binary </c> with option <c>compressed</c>. The
+ bug can cause <c>badarg</c> exception for a valid binary
+ when Erlang VM is linked against a <c>zlib</c> library of
+ version 1.2.9 or newer. Bug exists since OTP 17.0.</p>
+ <p>
+ Own Id: OTP-14159 Aux Id: ERL-340 </p>
+ </item>
+ </list>
+ </section>
+
+</section>
+
+<section><title>Erts 7.3.1.2</title>
+
+ <section><title>Fixed Bugs and Malfunctions</title>
+ <list>
+ <item>
+ <p>
+ Fixed a race that could cause a lost wakeup of a process
+ that timed out in a <c>receive ... after</c>. This bug
+ was introduced in ERTS version 7.0.</p>
+ <p>
+ Own Id: OTP-13798 Aux Id: OTP-11997 </p>
+ </item>
+ <item>
+ <p>
+ Fixed segfault after writing an erl crash dump.</p>
+ <p>
+ Own Id: OTP-13799</p>
+ </item>
+ </list>
+ </section>
+
+</section>
+
+<section><title>Erts 7.3.1.1</title>
+
+ <section><title>Fixed Bugs and Malfunctions</title>
+ <list>
+ <item>
+ <p>
+ Fix scheduler deadlock bug in <c>ets:update_counter/4</c>
+ when key is not found and inserting the default object
+ causes the table to grow.</p>
+ <p>
+ Own Id: OTP-13731 Aux Id: ERL-188 </p>
+ </item>
+ </list>
+ </section>
+
+</section>
+
<section><title>Erts 7.3.1</title>
<section><title>Fixed Bugs and Malfunctions</title>
@@ -1399,6 +5469,31 @@
</section>
+<section><title>Erts 7.2.1.1</title>
+
+ <section><title>Improvements and New Features</title>
+ <list>
+ <item>
+ <p>Introduced new statistics functionality in order to
+ more efficiently retrieve information about run able and
+ active processes and ports. For more information see:</p>
+ <list> <item><seealso
+ marker="erlang#statistics_total_run_queue_lengths"><c>statistics(total_run_queue_lengths)</c></seealso></item>
+ <item><seealso
+ marker="erlang#statistics_run_queue_lengths"><c>statistics(run_queue_lengths)</c></seealso></item>
+ <item><seealso
+ marker="erlang#statistics_total_active_tasks"><c>statistics(total_active_tasks)</c></seealso></item>
+ <item><seealso
+ marker="erlang#statistics_active_tasks"><c>statistics(active_tasks)</c></seealso></item>
+ </list>
+ <p>
+ Own Id: OTP-13201</p>
+ </item>
+ </list>
+ </section>
+
+</section>
+
<section><title>Erts 7.2.1</title>
<section><title>Fixed Bugs and Malfunctions</title>
@@ -2072,8 +6167,7 @@
<p>The previously introduced "eager check I/O" feature is
now enabled by default.</p>
<p>Eager check I/O can be disabled using the <c>erl</c>
- command line argument: <seealso
- marker="erl#+secio"><c>+secio false</c></seealso></p>
+ command line argument: <c>+secio false</c></p>
<p>Characteristics impact compared to previous
default:</p> <list> <item>Lower latency and smoother
management of externally triggered I/O operations.</item>
@@ -2474,6 +6568,103 @@
</section>
+<section><title>Erts 6.4.1.7</title>
+
+ <section><title>Fixed Bugs and Malfunctions</title>
+ <list>
+ <item>
+ <p>
+ A process communicating with a port via one of the
+ <c>erlang:port_*</c> BIFs could potentially end up in an
+ inconsistent state if the port terminated during the
+ communication. When this occurred the process could later
+ block in a <c>receive</c> even though it had messages
+ matching in its message queue.</p>
+ <p>
+ This bug was introduced in erts version 5.10 (OTP R16A).</p>
+ <p>
+ Own Id: OTP-13424 Aux Id: OTP-10336 </p>
+ </item>
+ <item>
+ <p>
+ Calls to <c>erl_drv_send_term()</c> or
+ <c>erl_drv_output_term()</c> from a non-scheduler thread
+ while the corresponding port was invalid caused the
+ emulator to enter an inconsistent state which eventually
+ caused an emulator crash.</p>
+ <p>
+ Own Id: OTP-13866</p>
+ </item>
+ <item>
+ <p>Driver and NIF operations accessing processes or ports
+ could cause an emulator crash when used from
+ non-scheduler threads. Those operations are:</p> <list>
+ <item><c>erl_drv_send_term()</c></item>
+ <item><c>driver_send_term()</c></item>
+ <item><c>erl_drv_output_term()</c></item>
+ <item><c>driver_output_term()</c></item>
+ <item><c>enif_send()</c></item>
+ <item><c>enif_port_command()</c></item> </list>
+ <p>
+ Own Id: OTP-13869</p>
+ </item>
+ <item>
+ <p>
+ Fix bug in <c>binary_to_term</c> for binaries created by
+ <c>term_to_binary </c> with option <c>compressed</c>. The
+ bug can cause <c>badarg</c> exception for a valid binary
+ when Erlang VM is linked against a <c>zlib</c> library of
+ version 1.2.9 or newer. Bug exists since OTP 17.0.</p>
+ <p>
+ Own Id: OTP-14159 Aux Id: ERL-340 </p>
+ </item>
+ <item>
+ <p>
+ Fixed bug in operator <c>bxor</c> causing erroneuos
+ result when one operand is a big <em>negative</em>
+ integer with the lowest <c>N*W</c> bits as zero and the
+ other operand not larger than <c>N*W</c> bits. <c>N</c>
+ is an integer of 1 or larger and <c>W</c> is 32 or 64
+ depending on word size.</p>
+ <p>
+ Own Id: OTP-14514</p>
+ </item>
+ <item>
+ <p>
+ Fixed bug in <c>binary_to_term</c> and
+ <c>binary_to_atom</c> that could cause VM crash.
+ Typically happens when the last character of an UTF8
+ string is in the range 128 to 255, but truncated to only
+ one byte. Bug exists in <c>binary_to_term</c> since ERTS
+ version 5.10.2 (OTP_R16B01) and <c>binary_to_atom</c>
+ since ERTS version 9.0 (OTP-20.0).</p>
+ <p>
+ Own Id: OTP-14590 Aux Id: ERL-474 </p>
+ </item>
+ </list>
+ </section>
+
+</section>
+
+<section><title>Erts 6.4.1.6</title>
+
+ <section><title>Fixed Bugs and Malfunctions</title>
+ <list>
+ <item>
+ <p>
+ When calling <c>garbage_collect/[1,2]</c> or
+ <c>check_process_code/[2,3]</c> from a process with a
+ higher priority than the priority of the process operated
+ on, the run queues could end up in an inconsistent state.
+ This bug has now been fixed.</p>
+ <p>
+ Own Id: OTP-13298 Aux Id: OTP-11388 </p>
+ </item>
+ </list>
+ </section>
+
+</section>
+
<section><title>Erts 6.4.1.5</title>
<section><title>Fixed Bugs and Malfunctions</title>
@@ -2854,8 +7045,7 @@
prioritized to the same extent as when eager check I/O is
disabled.</p>
<p>Eager check I/O can be enabled using the <c>erl</c>
- command line argument: <seealso
- marker="erl#+secio"><c>+secio true</c></seealso></p>
+ command line argument: <c>+secio true</c></p>
<p>Characteristics impact when enabled:</p> <list>
<item>Lower latency and smoother management of externally
triggered I/O operations.</item> <item>A slightly reduced
@@ -5438,7 +9628,7 @@
dependent, so applications aiming to be portable should
consider using <c>{ipv6_v6only,true}</c> when creating an
<c>inet6</c> listening/destination socket, and if
- neccesary also create an <c>inet</c> socket on the same
+ necessary also create an <c>inet</c> socket on the same
port for IPv4 traffic. See the documentation.</p>
<p>
Own Id: OTP-8928 Aux Id: kunagi-193 [104] </p>
@@ -5819,7 +10009,7 @@
This change of default value will reduce lock contention
on ETS tables using the <c>read_concurrency</c> option at
the expense of memory consumption when the amount of
- schedulers and logical processors are beween 8 and 64.
+ schedulers and logical processors are between 8 and 64.
For more information, see documentation of the <c>+rg</c>
command line argument of <c>erl(1)</c>.</p>
<p>
@@ -6796,7 +10986,7 @@
<p>
For the subsection about process_flag(save_calls, N)
there's an unrelated paragraph about process priorities
- which was copied from the preceeding subsection regarding
+ which was copied from the preceding subsection regarding
process_flag(priority, Level). (Thanks to Filipe David
Manana)</p>
<p>
@@ -8011,7 +12201,7 @@
<item>
<p>
Wx on MacOS X generated complains on stderr about certain
- cocoa functions not beeing called from the "Main thread".
+ cocoa functions not being called from the "Main thread".
This is now corrected.</p>
<p>
Own Id: OTP-9081</p>
@@ -8849,7 +13039,7 @@
<c>update_cpu_info</c> will make the runtime system
reread and update the internally stored CPU information.
For more information see the documentation of <seealso
- marker="erlang#update_cpu_info">erlang:system_info(update_cpu_info)</seealso>.</p>
+ marker="erlang#system_info_update_cpu_info">erlang:system_info(update_cpu_info)</seealso>.</p>
<p>
The CPU topology is now automatically detected on Windows
systems with less than 33 logical processors. The runtime
@@ -9002,7 +13192,7 @@
</item>
<item>
<p>The <c>empd</c> program could loop and consume 100%
- CPU time if an unexpected error ocurred in
+ CPU time if an unexpected error occurred in
<c>listen()</c> or <c>accept()</c>. Now <c>epmd</c> will
terminate if a non-recoverable error occurs. (Thanks to
Michael Santos.)</p>
@@ -15301,4 +19491,3 @@
</section>
</section>
</chapter>
-