diff options
Diffstat (limited to 'lib/compiler/doc/src')
| -rw-r--r-- | lib/compiler/doc/src/compile.xml | 61 | ||||
| -rw-r--r-- | lib/compiler/doc/src/notes.xml | 115 |
2 files changed, 156 insertions, 20 deletions
diff --git a/lib/compiler/doc/src/compile.xml b/lib/compiler/doc/src/compile.xml index bbd3f1043d..e1f24b602d 100644 --- a/lib/compiler/doc/src/compile.xml +++ b/lib/compiler/doc/src/compile.xml @@ -310,6 +310,23 @@ (there will not even be a warning if there is a mismatch).</p> </item> + <tag><c>{no_auto_import,[F/A, ...]}</c></tag> + <item> + <p>Makes the function <c>F/A</c> no longer beeing + auto-imported from the module <c>erlang</c>, which resolves + BIF name clashes. This option has to be used to resolve name + clashes with BIFs auto-imported before R14A, if one wants to + call the local function with the same name as an + auto-imported BIF without module prefix.</p> + <note> + <p>From R14A and forward, the compiler resolves calls + without module prefix to local or imported functions before + trying auto-imported BIFs. If the BIF is to be + called, use the <c>erlang</c> module prefix in the call, not + <c>{ no_auto_import,[F/A, ...]}</c></p> + </note> + </item> + </taglist> <p>If warnings are turned on (the <c>report_warnings</c> option @@ -338,31 +355,35 @@ <tag><c>nowarn_bif_clash</c></tag> <item> - <p>By default, there will be a compilation error if a - module contains an exported function with the same name - as an auto-imported BIF (such as <c>size/1</c>) AND - there is a call to it without a qualifying module name. - The reason is that the BIF will be called, not - the function in the same module. The recommended way to - eliminate that warning is to use a call with a module - name - either <c>erlang</c> to call the BIF or - <c>?MODULE</c> to call the function in the same module. - The warning can also be turned off using this option, - but that is not recommended.</p> + <p>This option is removed, it will generate a fatal error if used.</p> + + <warning> + <p>Beginning with R14A, the compiler no longer calls the + auto-imported BIF if the name clashes with a local or + explicitly imported function and a call without explicit + module name is issued. Instead the local or imported + function is called. Still accepting <c>nowarn_bif_clash</c> would makes a + module calling functions clashing with autoimported BIFs + compile with both the old and new compilers, but with + completely different semantics, why the option was removed.</p> - <p><em>The use of this option is strongly discouraged, - as code that uses it will probably break in a future - major release (R14 or R15).</em></p> + <p>The use of this option has always been strongly discouraged. + From OTP R14A and forward it's an error to use it.</p> + <p>To resolve BIF clashes, use explicit module names or the + <c>{no_auto_import,[F/A]}</c> compiler directive.</p> + </warning> </item> <tag><c>{nowarn_bif_clash, FAs}</c></tag> <item> - <p>Turns off warnings as <c>nowarn_bif_clash</c> but only - for the mentioned local functions. <c>FAs</c> is a tuple - <c>{Name,Arity}</c> or a list of such tuples.</p> - <p><em>The use of this option is strongly discouraged, - as code that uses it will probably break in a future - major release (R14 or R15).</em></p> + <p>This option is removed, it will generate a fatal error if used.</p> + + <warning> + <p>The use of this option has always been strongly discouraged. + From OTP R14A and forward it's an error to use it.</p> + <p>To resolve BIF clashes, use explicit module names or the + <c>{no_auto_import,[F/A]}</c> compiler directive.</p> + </warning> </item> <tag><c>warn_export_all</c></tag> diff --git a/lib/compiler/doc/src/notes.xml b/lib/compiler/doc/src/notes.xml index 7ea000a895..00ea0da55c 100644 --- a/lib/compiler/doc/src/notes.xml +++ b/lib/compiler/doc/src/notes.xml @@ -31,6 +31,121 @@ <p>This document describes the changes made to the Compiler application.</p> +<section><title>Compiler 4.7.1</title> + + <section><title>Improvements and New Features</title> + <list> + <item> + <p> + Eliminated warnings for auto-imported BIF clashes.</p> + <p> + Own Id: OTP-8840</p> + </item> + </list> + </section> + +</section> + +<section><title>Compiler 4.7</title> + + <section><title>Fixed Bugs and Malfunctions</title> + <list> + <item> + <p> + Several problems in the inliner have been fixed.</p> + <p> + Own Id: OTP-8552</p> + </item> + </list> + </section> + + + <section><title>Improvements and New Features</title> + <list> + <item> + <p> + The module binary from EEP31 (and EEP9) is implemented.</p> + <p> + Own Id: OTP-8217</p> + </item> + <item> + <p>Local and imported functions now override the + auto-imported BIFs when the names clash. The pre R14 + behaviour was that auto-imported BIFs would override + local functions. To avoid that old programs change + behaviour, the following will generate an error:</p> + <list><item><p>Doing a call without explicit module name + to a local function having a name clashing with the name + of an auto-imported BIF that was present (and + auto-imported) before OTP R14A</p></item> + <item><p>Explicitly importing a function having a name + clashing with the name of an autoimported BIF that was + present (and autoimported) before OTP R14A</p></item> + <item><p>Using any form of the old compiler directive + <c>nowarn_bif_clash</c></p></item> </list> <p>If the BIF + was added or auto-imported in OTP R14A or later, + overriding it with an import or a local function will + only result in a warning,</p> <p>To resolve clashes, you + can either use the explicit module name <c>erlang</c> to + call the BIF, or you can remove the auto-import of that + specific BIF by using the new compiler directive + <c>-compile({no_auto_import,[F/A]}).</c>, which makes all + calls to the local or imported function without explicit + module name pass without warnings or errors.</p> <p>The + change makes it possible to add auto-imported BIFs + without breaking or silently changing old code in the + future. However some current code ingeniously utilizing + the old behaviour or the <c>nowarn_bif_clash</c> compiler + directive, might need changing to be accepted by the + compiler.</p> + <p> + *** POTENTIAL INCOMPATIBILITY ***</p> + <p> + Own Id: OTP-8579</p> + </item> + <item> + <p>The undocumented, unsupport, and deprecated function + <c>lists:flat_length/1</c> has been removed.</p> + <p> + Own Id: OTP-8584</p> + </item> + <item> + <p>Nested records can now be accessed without + parenthesis. See the Reference Manual for examples. + (Thanks to YAMASHINA Hio and Tuncer Ayaz.)</p> + <p> + Own Id: OTP-8597</p> + </item> + <item> + <p>It is now possible to suppress the warning in code + such as "<c>list_to_integer(S), ok</c>" by assigning the + ignored value "_" like this: "<c>_ = list_to_integer(S), + ok</c>".</p> + <p> + Own Id: OTP-8602</p> + </item> + <item> + <p><c>receive</c> statements that can only read out a + newly created reference are now specially optimized so + that it will execute in constant time regardless of the + number of messages in the receive queue for the process. + That optimization will benefit calls to + <c>gen_server:call()</c>. (See <c>gen:do_call/4</c> for + an example of a receive statement that will be + optimized.)</p> + <p> + Own Id: OTP-8623</p> + </item> + <item> + <p>The compiler optimizes record operations better.</p> + <p> + Own Id: OTP-8668</p> + </item> + </list> + </section> + +</section> + <section><title>Compiler 4.6.5</title> <section><title>Fixed Bugs and Malfunctions</title> |