[committed] libstdc++: Document missing features for old std:string ABI [PR116777]
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Commit Message
Pushed to trunk.
-- >8 --
There are several features that are not supported when using the old
std::string ABI. It's possible that PR 81967 will get fixed, but the
missing C++20 features almost certainly won't be. Document this in the
manual.
libstdc++-v3/ChangeLog:
PR libstdc++/116777
* doc/xml/manual/using.xml: Document features that are not
supported for the gcc4-compatible ABI.
* doc/html/manual/using_dual_abi.html: Regenerate.
---
.../doc/html/manual/using_dual_abi.html | 18 ++++++++++++-
libstdc++-v3/doc/xml/manual/using.xml | 26 ++++++++++++++++++-
2 files changed, 42 insertions(+), 2 deletions(-)
@@ -22,7 +22,7 @@
of the macro is <code class="literal">1</code> which causes the new ABI to be active,
so to use the old ABI you must explicitly define the macro to
<code class="literal">0</code> before including any library headers.
- (Be aware that some GNU/Linux distributions configure GCC 5 differently so
+ (Be aware that some GNU/Linux distributions configured GCC 5 differently so
that the default value of the macro is <code class="literal">0</code> and users must
define it to <code class="literal">1</code> to enable the new ABI.)
</p><p> Although the changes were made for C++11 conformance, the choice of ABI
@@ -72,6 +72,22 @@
Handlers for <code class="classname">std::exception</code> will always catch
iostreams exceptions, because the old and new type both inherit from
<code class="classname">std::exception</code>.
+</p><p>
+ Some features are not supported when using the old ABI, including:
+ </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem">
+ Using <code class="classname">std::string::const_iterator</code> for
+ positional arguments to member functions such as
+ <code class="function">std::string::erase</code>.
+ </li><li class="listitem">
+ Allocator propagation in <code class="classname">std::string</code>.
+ </li><li class="listitem">
+ Using <code class="classname">std::string</code> at compile-time in
+ <code class="code">constexpr</code> functions.
+ </li><li class="listitem">
+ Class <code class="classname">std::chrono::time_zone</code> and all related APIs.
+ </li><li class="listitem">
+ The <code class="filename"><syncstream></code> header.
+ </li></ul></div><p>
</p><div class="section"><div class="titlepage"><div><div><h3 class="title"><a id="manual.intro.using.abi.trouble"></a>Troubleshooting</h3></div></div></div><p> If you get linker errors about undefined references to symbols
that involve types in the <code class="code">std::__cxx11</code> namespace or the tag
<code class="code">[abi:cxx11]</code> then it probably indicates that you are trying to
@@ -1368,7 +1368,7 @@ g++ -Winvalid-pch -I. -include stdc++.h -H -g -O2 hello.cc -o test.exe
of the macro is <literal>1</literal> which causes the new ABI to be active,
so to use the old ABI you must explicitly define the macro to
<literal>0</literal> before including any library headers.
- (Be aware that some GNU/Linux distributions configure GCC 5 differently so
+ (Be aware that some GNU/Linux distributions configured GCC 5 differently so
that the default value of the macro is <literal>0</literal> and users must
define it to <literal>1</literal> to enable the new ABI.)
</para>
@@ -1428,6 +1428,30 @@ g++ -Winvalid-pch -I. -include stdc++.h -H -g -O2 hello.cc -o test.exe
<classname>std::exception</classname>.
</para>
+<para>
+ Some features are not supported when using the old ABI, including:
+ <itemizedlist>
+ <listitem>
+ Using <classname>std::string::const_iterator</classname> for
+ positional arguments to member functions such as
+ <function>std::string::erase</function>.
+ </listitem>
+ <listitem>
+ Allocator propagation in <classname>std::string</classname>.
+ </listitem>
+ <listitem>
+ Using <classname>std::string</classname> at compile-time in
+ <code>constexpr</code> functions.
+ </listitem>
+ <listitem>
+ Class <classname>std::chrono::time_zone</classname> and all related APIs.
+ </listitem>
+ <listitem>
+ The <filename class="headerfile"><syncstream></filename> header.
+ </listitem>
+ </itemizedlist>
+</para>
+
<section xml:id="manual.intro.using.abi.trouble" xreflabel="Dual ABI Troubleshooting"><info><title>Troubleshooting</title></info>
<para> If you get linker errors about undefined references to symbols