diff options
Diffstat (limited to 'lib/compiler/doc/src/notes.xml')
| -rw-r--r-- | lib/compiler/doc/src/notes.xml | 481 |
1 files changed, 471 insertions, 10 deletions
diff --git a/lib/compiler/doc/src/notes.xml b/lib/compiler/doc/src/notes.xml index cb39b28d3d..6db8d19b5a 100644 --- a/lib/compiler/doc/src/notes.xml +++ b/lib/compiler/doc/src/notes.xml @@ -8,16 +8,17 @@ <holder>Ericsson AB. All Rights Reserved.</holder> </copyright> <legalnotice> - The contents of this file are subject to the Erlang Public License, - Version 1.1, (the "License"); you may not use this file except in - compliance with the License. You should have received a copy of the - Erlang Public License along with this software. If not, it can be - retrieved online at http://www.erlang.org/. - - Software distributed under the License is distributed on an "AS IS" - basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See - the License for the specific language governing rights and limitations - under the License. + Licensed under the Apache License, Version 2.0 (the "License"); + you may not use this file except in compliance with the License. + You may obtain a copy of the License at + + http://www.apache.org/licenses/LICENSE-2.0 + + Unless required by applicable law or agreed to in writing, software + distributed under the License is distributed on an "AS IS" BASIS, + WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + See the License for the specific language governing permissions and + limitations under the License. </legalnotice> @@ -31,6 +32,466 @@ <p>This document describes the changes made to the Compiler application.</p> +<section><title>Compiler 6.0</title> + + <section><title>Fixed Bugs and Malfunctions</title> + <list> + <item> + <p> + The compiler optimizes away building of terms that are + never actually used. As a result, the compiler in OTP 18 + may produce more warnings for terms that are built but + not used than the compiler in OTP 17.</p> + <p> + Own Id: OTP-12453</p> + </item> + <item> + <p> + Using a map could incorrectly suppress warnings for + unused variables.</p> + <p> + Own Id: OTP-12515</p> + </item> + <item> + <p> + The compiler now properly reports unknown parse + transforms. That is, <c>undef</c> exceptions coming from + the parse transform itself is reported differently from + the absence of the parse transform.</p> + <p> + Own Id: OTP-12723</p> + </item> + <item> + <p> + Allow for 'creation of sub binary delayed' optimization + if maps instructions are in a clause.</p> + <p> + Own Id: OTP-12758</p> + </item> + </list> + </section> + + + <section><title>Improvements and New Features</title> + <list> + <item> + <p> + The <c>cerl</c> and <c>cerl_trees</c> modules in the + <c>compiler</c> application are now documented.</p> + <p> + Own Id: OTP-11978</p> + </item> + <item> + <p> + The deprecated '<c>asm</c>' option has been removed.</p> + <p> + *** POTENTIAL INCOMPATIBILITY ***</p> + <p> + Own Id: OTP-12100</p> + </item> + <item> + <p> + Support variables as Map keys in expressions and patterns</p> + <p>Erlang will accept any expression as keys in Map + expressions and it will accept literals or bound + variables as keys in Map patterns.</p> + <p> + Own Id: OTP-12218</p> + </item> + <item> + <p> + Infer Map type information in beam_type compiler + optimization pass.</p> + <p> + Own Id: OTP-12253</p> + </item> + <item> + <p> + Compiler optimizations have been improved.</p> + <p> + Own Id: OTP-12393</p> + </item> + <item> + <p> + Five undocumented functions in the module <c>core_lib</c> + have been deprecated and will be removed in the next + major release. The functions are: <c>get_anno/{1,2}</c>, + <c>is_literal/1</c>, <c>is_literal_list/1</c>, and + <c>literal_value</c>. Use the appropriate functions in + the <c>cerl</c> module instead.</p> + <p> + Own Id: OTP-12497</p> + </item> + <item> + <p> + Change some internal data structures to Maps in order to + speed up compilation time. Measured speed up is around + 10%-15%.</p> + <p> + Own Id: OTP-12774</p> + </item> + <item> + <p> + Fix beam_bool pass for Maps instruction get_map_elements</p> + <p> + Before beam_split the get_map_elements instruction is + still in blocks and the helper function in beam_jump did + not reflect this.</p> + <p> + Own Id: OTP-12844 Aux Id: 17 </p> + </item> + </list> + </section> + +</section> + +<section><title>Compiler 5.0.4</title> + + <section><title>Fixed Bugs and Malfunctions</title> + <list> + <item> + <p> + Matching out a map from a record and then updating the + record could cause a 'badarg' exception at run-time. + (Thanks to Dmitry Aleksandrov for reporting this bug.)</p> + <p> + Own Id: OTP-12402</p> + </item> + <item> + <p>The compiler would crash when compiling some complex, + nonsensical guards such as:</p> + <p> ... <c>when {{X}}, -X</c>...</p> + <p> + Own Id: OTP-12410</p> + </item> + <item> + <p> + In rare circumstances, using binary pattern in the value + part of a map pattern would cause the compiler to crash.</p> + <p> + Own Id: OTP-12414</p> + </item> + <item> + <p>Case expressions where a map was wrapped in a tuple or + list such as:</p> + <p><c>case {a,Map} of</c><br/> <c>{a,#{k:=_}}=Tuple -> + Tuple</c><br/> <c>end.</c></p> + <p>would be unsafely "optimized" to either cause an + exception at run-time or would return an empty map.</p> + <p> + Own Id: OTP-12451</p> + </item> + <item> + <p>When a variable was compared to a literal map using + the '<c>==</c>' operator, the compiler would change the + operator to '<c>=:=</c>' since it is more efficient. + However, this optimization is not safe if the map literal + has numeric keys or values. The compiler will now only do + the optimization if all keys and values are + non-numeric.</p> + <p> + Own Id: OTP-12456</p> + </item> + </list> + </section> + +</section> + +<section><title>Compiler 5.0.3</title> + + <section><title>Fixed Bugs and Malfunctions</title> + <list> + <item> + <p> + Named funs with the same name and arity could get mixed + up with each other.</p> + <p> + Own Id: OTP-12262</p> + </item> + <item> + <p> + Coalesce map keys in dialyzer mode</p> + <p> + This fixes a regression introduced in commit + 805f9c89fc01220bc1bb0f27e1b68fd4eca688ba The problem + occurred with compounded map keys compiled with dialyzer + option turned on, '+dialyzer'.</p> + <p> + Reported by: Ivan Uemlianin</p> + <p> + Own Id: OTP-12347</p> + </item> + </list> + </section> + +</section> + +<section><title>Compiler 5.0.2</title> + + <section><title>Fixed Bugs and Malfunctions</title> + <list> + <item> + <p> + Corrected a bug with incorrect code generation when + inlining was turned on.</p> + <p> + Own Id: OTP-12132</p> + </item> + </list> + </section> + +</section> + +<section><title>Compiler 5.0.1</title> + + <section><title>Fixed Bugs and Malfunctions</title> + <list> + <item> + <p> + A Dialyzer crash involving analysis of Map types has now + been fixed.</p> + <p> + Own Id: OTP-11947</p> + </item> + <item> + <p>The compiler would fail to compile a file with a + latin-1 character in the false branch of an <c>-ifdef</c> + or <c>-indef</c>.</p> + <p> + Own Id: OTP-11987</p> + </item> + </list> + </section> + +</section> + +<section><title>Compiler 5.0</title> + + <section><title>Fixed Bugs and Malfunctions</title> + <list> + <item> + <p> + Line numbers would not be correct when a binary + construction such as + '<c><<Bin/binary,...>></c>' fails. (Thanks to + Stanislav Seletskiy for reporting this bug.)</p> + <p> + Own Id: OTP-11572</p> + </item> + <item> + <p> + The compiler now properly annotates the code in value in + the '<c>after</c>' clause for a '<c>try</c>' so that + Dialyzer no longer generates a false warning for an + unmatched return.</p> + <p> + Own Id: OTP-11580</p> + </item> + <item> + <p> + Some case statements where no clause would match could + cause an internal error in the compiler. (Thanks to Erik + Soe Sorensen for reporting this bug.)</p> + <p> + Own Id: OTP-11610</p> + </item> + <item> + <p> + With <c>--Wunmatched_returns</c>, dialyzer will no longer + warn when the value of a list comprehension is ignored, + provided that the each value in the list would be an + atomic value (such as integer or atoms, as opposed to + tuples and lists). Example: ignoring '<c>[io:format(...) + || ...]</c>' will not cause a warning, while ignoring + '<c>[file:close(Fd) || ...]</c>' will.</p> + <p> + Own Id: OTP-11626</p> + </item> + <item> + <p> + Matching out a binary and applying the binary as if it + were a fun would crash the run-time system. (Thanks to + Loïc Hoguin.)</p> + <p> + Own Id: OTP-11672</p> + </item> + <item> + <p> + Some local implementations of removing the last element + from a list are replaced by <c>lists:droplast/1</c>. Note + that this requires at least <c>stdlib-2.0</c>, which is + the stdlib version delivered in OTP 17.0. (Thanks to Hans + Svensson)</p> + <p> + Own Id: OTP-11678</p> + </item> + <item> + <p> + Allow all auto imports to be suppressed at once. + Introducing the no_auto_import attribute: + -compile(no_auto_import). Useful for code generation + tools that always use the qualified function names and + want to avoid the auto imported functions clashing with + local ones. (Thanks to José Valim.)</p> + <p> + Own Id: OTP-11682</p> + </item> + <item> + <p> + Application upgrade (appup) files are corrected for the + following applications: </p> + <p> + <c>asn1, common_test, compiler, crypto, debugger, + dialyzer, edoc, eldap, erl_docgen, et, eunit, gs, hipe, + inets, observer, odbc, os_mon, otp_mibs, parsetools, + percept, public_key, reltool, runtime_tools, ssh, + syntax_tools, test_server, tools, typer, webtool, wx, + xmerl</c></p> + <p> + A new test utility for testing appup files is added to + test_server. This is now used by most applications in + OTP.</p> + <p> + (Thanks to Tobias Schlager)</p> + <p> + Own Id: OTP-11744</p> + </item> + <item> + <p> + Adapt 'asm' deprecation message to new version scheme. + (Thanks to Tuncer Ayaz)</p> + <p> + Own Id: OTP-11751</p> + </item> + <item> + <p> + A number of compiler errors where unusual or nonsensical + code would crash the compiler have been reported by Ulf + Norell and corrected by Anthony Ramine.</p> + <p> + Own Id: OTP-11770</p> + </item> + </list> + </section> + + + <section><title>Improvements and New Features</title> + <list> + <item> + <p> + Compilation times for modules with a huge number for + record accesses using the dot operator has been improved.</p> + <p> + Own Id: OTP-10652</p> + </item> + <item> + <p> + The compiler can generate somewhat better code by moving + let expressions into sequences. (Thanks to Anthony + Ramine.)</p> + <p> + Own Id: OTP-11056</p> + </item> + <item> + <p> + Forbid unsized fields in patterns of binary generators + and simplified v3_core's translation of bit string + generators. (Thanks to Anthony Ramine.)</p> + <p> + Own Id: OTP-11186</p> + </item> + <item> + <p> + Funs can now be a given a name. Thanks to to Richard + O'Keefe for the idea (EEP37) and to Anthony Ramine for + the implementation.</p> + <p> + Own Id: OTP-11537</p> + </item> + <item> + <p> + Using the <c>from_asm</c> option to produce a BEAM file + starting from BEAM assembly code would often fail because + early optimization passes would not understand + instructions that later optimization passes would + introduce. (Thanks to Anthony Ramine.)</p> + <p> + Own Id: OTP-11544</p> + </item> + <item> + <p> + The <c>.core</c> and <c>.S</c> extensions are now + documented in the <c>erlc</c> documentation, and the + '<c>from_core</c>' and '<c>from_asm</c>' options are now + documented in the compiler documentation. (Thanks to + Tuncer Ayaz.)</p> + <p> + Own Id: OTP-11547</p> + </item> + <item> + <p>Optimization of case expressions that build tuples or + lists have been improved.</p> + <p> + Own Id: OTP-11584</p> + </item> + <item> + <p> + EEP43: New data type - Maps</p> + <p> + With Maps you may for instance: <taglist> <item><c>M0 = + #{ a => 1, b => 2}, % create + associations</c></item> <item><c>M1 = M0#{ a := 10 }, % + update values</c></item> <item><c>M2 = M1#{ "hi" => + "hello"}, % add new associations</c></item> <item><c>#{ + "hi" := V1, a := V2, b := V3} = M2. % match keys with + values</c></item> </taglist></p> + <p> + For information on how to use Maps please see Map Expressions in the + <seealso marker="doc/reference_manual:expressions#map_expressions"> + Reference Manual</seealso>.</p> + <p> + The current implementation is without the following + features: <taglist> <item>No variable keys</item> + <item>No single value access</item> <item>No map + comprehensions</item> </taglist></p> + <p> + Note that Maps is <em>experimental</em> during OTP 17.0.</p> + <p> + Own Id: OTP-11616</p> + </item> + <item> + <p> + Some function specs are corrected or moved and some edoc + comments are corrected in order to allow use of edoc. + (Thanks to Pierre Fenoll)</p> + <p> + Own Id: OTP-11702</p> + </item> + <item> + <p> + Thanks to Anthony Ramine for several improvements to the + optimizations in the BEAM compiler and for cleaning up + the code the code that transforms list and binary + comprehensions to Core Erlang.</p> + <p> + Own Id: OTP-11720</p> + </item> + <item> + <p> + The default encoding for Erlang source files is now + UTF-8. As a temporary measure to ease the transition from + the old default of latin-1, if the compiler encounters + byte sequences that are not valid UTF-8 sequences, the + compiler will re-try the compilation in latin-1 mode. + This workaround will be removed in a future release.</p> + <p> + Own Id: OTP-11791</p> + </item> + </list> + </section> + +</section> + <section><title>Compiler 4.9.4</title> <section><title>Fixed Bugs and Malfunctions</title> |