When I updated those URLs in June 2015, I must have missed these references in libstdc++ land.
Fixed thusly (via revision 244001), and I plan on backporting to GCC 6 and possibly GCC 5 later. Gerald 2017-01-01 Gerald Pfeifer <ger...@pfeifer.com> * doc/xml/faq.xml: Update address of C++ ABI link. * doc/xml/manual/abi.xml: Ditto. Index: doc/xml/faq.xml =================================================================== --- doc/xml/faq.xml (revision 243528) +++ doc/xml/faq.xml (working copy) @@ -1230,7 +1230,7 @@ details than for C, and most CPU designers (for good reasons elaborated below) have not stepped up to publish C++ ABIs. Such an ABI has been defined for the Itanium architecture (see - <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://www.codesourcery.com/cxx-abi/">C++ + <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://mentorembedded.github.io/cxx-abi/">C++ ABI for Itanium</link>) and that is used by G++ and other compilers as the de facto standard ABI on many common architectures (including x86). G++ can also use the ARM architecture's EABI, for embedded Index: doc/xml/manual/abi.xml =================================================================== --- doc/xml/manual/abi.xml (revision 243528) +++ doc/xml/manual/abi.xml (working copy) @@ -42,7 +42,7 @@ virtual functions, etc. These details are defined as the compiler Application Binary Interface, or ABI. The GNU C++ compiler uses an industry-standard C++ ABI starting with version 3. Details can be - found in the <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://mentorembedded.github.com/cxx-abi/abi.html">ABI + found in the <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://mentorembedded.github.io/cxx-abi/abi.html">ABI specification</link>. </para> @@ -736,7 +736,7 @@ the way the compiler deals with this class in by-value return statements or parameters: instead of passing instances of this class in registers, the compiler will be forced to use memory. See the -section on <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://mentorembedded.github.com/cxx-abi/abi.html#calls">Function +section on <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://mentorembedded.github.io/cxx-abi/abi.html#calls">Function Calling Conventions and APIs</link> of the C++ ABI documentation for further details. </para></listitem> @@ -1094,7 +1094,7 @@ <biblioentry xml:id="biblio.cxxabi"> <title> <link xmlns:xlink="http://www.w3.org/1999/xlink" - xlink:href="http://www.codesourcery.com/cxx-abi/"> + xlink:href="http://mentorembedded.github.io/cxx-abi/"> C++ ABI Summary </link> </title>