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diff --git a/lib/compiler/doc/src/notes.xml b/lib/compiler/doc/src/notes.xml index 7addadf82c..f11444137d 100644 --- a/lib/compiler/doc/src/notes.xml +++ b/lib/compiler/doc/src/notes.xml @@ -32,6 +32,272 @@ <p>This document describes the changes made to the Compiler application.</p> +<section><title>Compiler 7.4.4</title> + + <section><title>Fixed Bugs and Malfunctions</title> + <list> + <item> + <p>Fixed a compiler crash introduced in <c>22.0.6</c> + (OTP-15952).</p> + <p> + Own Id: OTP-15953 Aux Id: ERL-999 </p> + </item> + </list> + </section> + +</section> + +<section><title>Compiler 7.4.3</title> + + <section><title>Fixed Bugs and Malfunctions</title> + <list> + <item> + <p>Fixed an unsafe optimization when matching + <c>tuple_size/1</c> outside of guards, which could crash + the emulator if the argument was not a tuple.</p> + <p> + Own Id: OTP-15945</p> + </item> + <item> + <p>Fixed a rare bug that could cause the wrong kind of + exception to be thrown when a BIF failed in a function + that matched bitstrings.</p> + <p> + Own Id: OTP-15946</p> + </item> + <item> + <p>Fixed a bug where receive statements inside try/catch + blocks could return incorrect results.</p> + <p> + Own Id: OTP-15952</p> + </item> + </list> + </section> + +</section> + +<section><title>Compiler 7.4.2</title> + + <section><title>Fixed Bugs and Malfunctions</title> + <list> + <item> + <p>Fixed an incorrect type determination for constructed + binaries, which could cause <c>is_binary</c> checks to + succeed when they shouldn't have.</p> + <p> + Own Id: OTP-15872</p> + </item> + </list> + </section> + +</section> + +<section><title>Compiler 7.4.1</title> + + <section><title>Fixed Bugs and Malfunctions</title> + <list> + <item> + <p>The type optimization pass of the compiler could hang + or loop for a long time when analyzing a + <c>setelement/3</c> call with a varible position.</p> + <p> + Own Id: OTP-15828 Aux Id: ERL-948 </p> + </item> + <item> + <p>Certain complex receive statements would result in an + internal compiler failure.</p> + <p> + Own Id: OTP-15832 Aux Id: ERL-950 </p> + </item> + <item> + <p>Fixed an unsafe type optimization.</p> + <p> + Own Id: OTP-15838</p> + </item> + <item> + <p>Fixed a crash when optimizing compiler-generated + exceptions (like badmatch) whose offending term was a + constructed binary.</p> + <p> + Own Id: OTP-15839 Aux Id: ERL-954 </p> + </item> + <item> + <p>Fixed a bad optimization related to the <c>++/2</c> + operator, where the compiler assumed that it always + produced a list (<c>[] ++ RHS</c> returns <c>RHS</c> + verbatim, even if it's not a list).</p> + <p> + Own Id: OTP-15841</p> + </item> + <item> + <p>An <c>is_binary/1</c> test followed by + <c>is_bitstring/1</c> (or vice versa) could fail because + of an usafe optimization.</p> + <p> + Own Id: OTP-15845</p> + </item> + <item> + <p>A Core Erlang module where the last clause in a + <c>case</c> matched a map would fail to load.</p> + <p> + Own Id: OTP-15846 Aux Id: ERL-955 </p> + </item> + <item> + <p>Fixed a bug that could cause the compiler to crash + when compiling complex nested case expressions.</p> + <p> + Own Id: OTP-15848 Aux Id: ERL-956 </p> + </item> + </list> + </section> + +</section> + +<section><title>Compiler 7.4</title> + + <section><title>Fixed Bugs and Malfunctions</title> + <list> + <item> + <p><c>record_info/2</c> is a pseudo-function that + requires literal arguments known at compile time. + Therefore, the following usage is illegal: <c>fun + record/info/2</c>. The compiler would crash when during + compilation of that kind of code. Corrected to issue a + compilation error.</p> + <p> + Own Id: OTP-15760 Aux Id: ERL-907 </p> + </item> + </list> + </section> + + + <section><title>Improvements and New Features</title> + <list> + <item> + <p> + The compiler has been rewritten to internally use an + intermediate representation based on Static Single + Assignment (SSA). The new intermediate representation + makes more optimizations possible.</p> + <p> + Most noticeable is that the binary matching optimizations + are now applicable in many more circumstances than + before.</p> + <p> + Another noticeable change is that type optimizations are + now applied across local function calls, and will remove + a lot more redundant type tests than before.</p> + <p> + Own Id: OTP-14894 Aux Id: ERL-714 </p> + </item> + <item> + <p>Funs are no longer created when they are only used + locally, greatly improving the performance of named funs + and "fun-wrapped" macros.</p> + <p> + Own Id: OTP-15273 Aux Id: ERL-639 </p> + </item> + <item> + <p>All compiler options that can be given in the source + file can now also be given in the option list or from the + command line for <c>erlc</c>.</p> + <p>Specifically, the option + <c>{nowarn_deprecated_function,MFAs}</c> was only + recognized when given in the file with the attribute + <c>-compile()</c>. The option + <c>{nowarn_unused_function,FAs}</c> was incorrectly + documented to only work in a file, but it also worked + when given in the option list.</p> + <p> + Own Id: OTP-15456</p> + </item> + <item> + <p> Do not allow function specifications for functions + residing in other modules. </p> + <p> + *** POTENTIAL INCOMPATIBILITY ***</p> + <p> + Own Id: OTP-15563 Aux Id: ERL-845, OTP-15562 </p> + </item> + <item> + <p>Internal documentation has now been added to the + <em>Erts</em> and <em>Compiler</em> applications.</p> + <p>The internal documents for <em>Erts</em> describe + miscellaneous interesting implementation details. Those + details can change at any time.</p> + <p>The internal documentation for <em>Compiler</em> + documents the API for the Core Erlang modules. While we + will not change those APIs without good reason, we don't + give the same guarantees about backward compatibility as + for the rest of the APIs in OTP.</p> + <p> + Own Id: OTP-15715</p> + </item> + <item> + <p> There are new compiler options <c>nowarn_removed</c> + and <c>{nowarn_removed,Items}</c> to suppress warnings + for functions and modules that have been removed from + OTP.</p> + <p> + Own Id: OTP-15749 Aux Id: ERL-904 </p> + </item> + </list> + </section> + +</section> + +<section><title>Compiler 7.3.2</title> + + <section><title>Fixed Bugs and Malfunctions</title> + <list> + <item> + <p>An expression such as <c>(A / B) band 16#ff</c> would + crash the compiler.</p> + <p> + Own Id: OTP-15518 Aux Id: ERL-829 </p> + </item> + <item> + <p>There could be an incorrect warning when the + <c>tuple_calls</c> option was given. The generated code + would be correct. Here is an example of code that would + trigger the warning:</p> + <p><c>(list_to_atom("prefix_" ++ + atom_to_list(suffix))):doit(X)</c>.</p> + <p> + Own Id: OTP-15552 Aux Id: ERL-838 </p> + </item> + <item> + <p>Optimize (again) Dialyzer's handling of + left-associative use of <c>andalso</c> and <c>orelse</c> + in guards.</p> + <p> + Own Id: OTP-15577 Aux Id: ERL-851, PR-2141, PR-1944 </p> + </item> + </list> + </section> + +</section> + +<section><title>Compiler 7.3.1</title> + + <section><title>Fixed Bugs and Malfunctions</title> + <list> + <item> + <p>An optimization that avoided allocation of a stack + frame for some <c>case</c> expressions was introduced in + OTP 21. (ERL-504/OTP-14808) It turns out that in rare + circumstances, this optimization is not safe. Therefore, + this optimization has been disabled.</p> + <p>A similar optimization will be included in OTP 22 in a + safe way.</p> + <p> + Own Id: OTP-15501 Aux Id: ERL-807, ERL-514, OTP-14808 </p> + </item> + </list> + </section> + +</section> + <section><title>Compiler 7.3</title> <section><title>Fixed Bugs and Malfunctions</title> |