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| author | Craig Jennings <c@cjennings.net> | 2025-08-14 22:58:58 -0500 |
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| committer | Craig Jennings <c@cjennings.net> | 2025-08-14 22:58:58 -0500 |
| commit | 82ba818ff456bcd6d56a06226e3f27e98fbb55c3 (patch) | |
| tree | 158cfc17b2f644a10f063cb546752cfaae12c97f /devdocs/c/language%2Fattributes%2Freproducible.html | |
| parent | 9278ddd4ea1a8b1a4c1edaa8894516e3f48d245b (diff) | |
| download | dotemacs-82ba818ff456bcd6d56a06226e3f27e98fbb55c3.tar.gz dotemacs-82ba818ff456bcd6d56a06226e3f27e98fbb55c3.zip | |
removing all downloaded devdocs files
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| -rw-r--r-- | devdocs/c/language%2Fattributes%2Freproducible.html | 22 |
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diff --git a/devdocs/c/language%2Fattributes%2Freproducible.html b/devdocs/c/language%2Fattributes%2Freproducible.html deleted file mode 100644 index fa0bc584..00000000 --- a/devdocs/c/language%2Fattributes%2Freproducible.html +++ /dev/null @@ -1,22 +0,0 @@ - <h1 id="firstHeading" class="firstHeading">C attribute: unsequenced, reproducible <span class="t-mark-rev t-since-c23">(since C23)</span> -</h1> <p>Provides the compiler with information about the access of objects by a function such that certain properties of function calls can be deduced.</p> -<h3 id="Syntax"> Syntax</h3> <table class="t-sdsc-begin"> <tr class="t-sdsc"> <td> <code>[[</code> <code>unsequenced</code> <code>]]</code><br><code>[[</code> <code>__unsequenced__</code> <code>]]</code> </td> <td> (1) </td> <td class="t-sdsc-nopad"> </td> -</tr> <tr class="t-sdsc"> <td> <code>[[</code> <code>reproducible</code> <code>]]</code><br><code>[[</code> <code>__reproducible__</code> <code>]]</code> </td> <td> (2) </td> <td class="t-sdsc-nopad"> </td> -</tr> -</table> <div class="t-li1"> -<span class="t-li">1)</span> Indicates that a function is effectless, idempotent, stateless, and independent</div> <div class="t-li1"> -<span class="t-li">2)</span> Indicates that a function is effectless and idempotent</div> <h3 id="Explanation"> Explanation</h3> <p>These attributes apply to a function declarator or to a type specifier that has a function type. The corresponding attribute is a property of the function type.</p> -<h4 id="Effectless"> Effectless</h4> <p>An evaluation of a function call is effectless if any store operation that is sequenced during the call is the modification of an object that synchronizes with the call; if additionally the operation is observable, all access to the object must be based on a unique pointer parameter of the function.</p> -<h4 id="Idempotent"> Idempotent</h4> <p>An evaluation <span class="t-spar">E</span> is idempotent if a second evaluation of <span class="t-spar">E</span> can be sequenced immediately after the original one without changing the resulting value, if any, or the observable state of the execution.</p> -<h4 id="Stateless"> Stateless</h4> <p>A function <span class="t-spar">F</span> is stateless if any definition of an object of static or thread <a href="../storage_duration" title="c/language/storage duration">storage duration</a> in <span class="t-spar">F</span> or in a function that is called by <span class="t-spar">F</span> is <code>const</code> but not <code>volatile</code> qualified.</p> -<h4 id="Independent"> Independent</h4> <p>A function <span class="t-spar">F</span> is independent if for any object <span class="t-spar">X</span> that is observed by a call to <span class="t-spar">F</span> through an lvalue that is not based on a parameter of the call, all accesses to <span class="t-spar">X</span> in all calls to <span class="t-spar">F</span> during the same program execution observe the same value; otherwise if the access is based on a pointer parameter, there shall be a unique such pointer parameter <span class="t-spar">P</span> such that any access to <span class="t-spar">X</span> shall be to an lvalue that is based on <span class="t-spar">P</span>.</p> -<p>An object <span class="t-spar">X</span> is observed by a function call if both synchronize, if <span class="t-spar">X</span> is not local to the call, if <span class="t-spar">X</span> has a lifetime that starts before the function call, and if an access of <span class="t-spar">X</span> is sequenced during the call; the last value of <span class="t-spar">X</span>, if any, that is stored before the call is said to be the value of <span class="t-spar">X</span> that is observed by the call.</p> -<h3 id="Notes"> Notes</h3> <p>These attributes exist for the purpose of compiler optimization.</p> -<p>If a function is reproducible, multiple subsequent calls can be treated as a single call.</p> -<p>If a function is unsequenced, multiple subsequent calls can be treated as a single call, and the calls can be parallelized and reordered arbitrarily.</p> -<div class="_attribution"> - <p class="_attribution-p"> - © cppreference.com<br>Licensed under the Creative Commons Attribution-ShareAlike Unported License v3.0.<br> - <a href="https://en.cppreference.com/w/c/language/attributes/reproducible" class="_attribution-link">https://en.cppreference.com/w/c/language/attributes/reproducible</a> - </p> -</div> |
