https://gcc.gnu.org/g:6a8b3a63089745b945bebe7ba21104060a2edbb1
commit r16-6337-g6a8b3a63089745b945bebe7ba21104060a2edbb1 Author: Tomasz Kamiński <[email protected]> Date: Mon Dec 22 11:53:45 2025 +0100 libstdc++/doc: Document generate_canonical and variant compat macros. The _GLIBCXX_USE_OLD_GENERATE_CANONICAL was introduced by r16-6177-g866bc8a9214b1d that implemented P0952R2 [1] resolution for LWG2524 as DR against C++20. The _GLIBCXX_USE_VARIANT_CXX17_OLD_ABI was introduced by r16-6301-gb3c167b61fd75f that resovled PR112591. [1] https://www.open-std.org/jtc1/sc22/wg21/docs/papers/2023/p0952r2.html libstdc++-v3/ChangeLog: * doc/html/manual/using_macros.html: Regenerate. * doc/xml/manual/using.xml: Add entries for _GLIBCXX_USE_OLD_GENERATE_CANONICAL and _GLIBCXX_USE_VARIANT_CXX17_OLD_ABI. Reviewed-by: Jonathan Wakely <[email protected]> Signed-off-by: Tomasz Kamiński <[email protected]> Diff: --- libstdc++-v3/doc/html/manual/using_macros.html | 10 ++++++++++ libstdc++-v3/doc/xml/manual/using.xml | 20 ++++++++++++++++++++ 2 files changed, 30 insertions(+) diff --git a/libstdc++-v3/doc/html/manual/using_macros.html b/libstdc++-v3/doc/html/manual/using_macros.html index c1406ec76f77..b1d05d99d760 100644 --- a/libstdc++-v3/doc/html/manual/using_macros.html +++ b/libstdc++-v3/doc/html/manual/using_macros.html @@ -137,4 +137,14 @@ When not defined, durations, time points, and calendar types are available for freestanding, but the standard clocks and the time zone database are not (because they require OS support). + </p></dd><dt><span class="term"><code class="code">_GLIBCXX_USE_OLD_GENERATE_CANONICAL</code></span></dt><dd><p> + Undefined by default. When defined <code class="code">generate_canonical</code> + reverts to the algorithm used prior to the implementation of + <a class="link" href="https://www.open-std.org/jtc1/sc22/wg21/docs/papers/2023/p0952r2.html"; target="_top"> + P0952: A new specification for std::generate_canonical</a> in GCC-16. + </p></dd><dt><span class="term"><code class="code">_GLIBCXX_USE_VARIANT_CXX17_OLD_ABI</code></span></dt><dd><p> + Undefined by default. When defined <code class="code">variant</code> in C++17 + mode will revert to the non-conforming implementation used prior to the + <a class="link" href="https://gcc.gnu.org/bugzilla/show_bug.cgi?id=112591"; target="_top">PR112591</a> + in GCC-16. Has no impact for C++20 or later modes. </p></dd></dl></div></div><div class="navfooter"><hr /><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="using_headers.html">Prev</a> </td><td width="20%" align="center"><a accesskey="u" href="using.html">Up</a></td><td width="40%" align="right"> <a accesskey="n" href="using_dual_abi.html">Next</a></td></tr><tr><td width="40%" align="left" valign="top">Headers </td><td width="20%" align="center"><a accesskey="h" href="../index.html">Home</a></td><td width="40%" align="right" valign="top"> Dual ABI</td></tr></table></div></body></html> \ No newline at end of file diff --git a/libstdc++-v3/doc/xml/manual/using.xml b/libstdc++-v3/doc/xml/manual/using.xml index bec5419d587a..8adfecfe54ba 100644 --- a/libstdc++-v3/doc/xml/manual/using.xml +++ b/libstdc++-v3/doc/xml/manual/using.xml @@ -1343,6 +1343,26 @@ g++ -Winvalid-pch -I. -include stdc++.h -H -g -O2 hello.cc -o test.exe database are not (because they require OS support). </para> </listitem></varlistentry> + <varlistentry><term><code>_GLIBCXX_USE_OLD_GENERATE_CANONICAL</code></term> + <listitem> + <para> + Undefined by default. When defined <code>generate_canonical</code> + reverts to the algorithm used prior to the implementation of + <link xmlns:xlink="http://www.w3.org/1999/xlink"; + xlink:href="https://www.open-std.org/jtc1/sc22/wg21/docs/papers/2023/p0952r2.html";> + P0952: A new specification for std::generate_canonical</link> in GCC-16. + </para> + </listitem></varlistentry> + <varlistentry><term><code>_GLIBCXX_USE_VARIANT_CXX17_OLD_ABI</code></term> + <listitem> + <para> + Undefined by default. When defined <code>variant</code> in C++17 + mode will revert to the non-conforming implementation used prior to the + <link xmlns:xlink="http://www.w3.org/1999/xlink"; + xlink:href="https://gcc.gnu.org/bugzilla/show_bug.cgi?id=112591";>PR112591</link> + in GCC-16. Has no impact for C++20 or later modes. + </para> + </listitem></varlistentry> </variablelist> </section>
