Committed to CVS.
Index: htdocs/gcc-9/changes.html =================================================================== RCS file: /cvs/gcc/wwwdocs/htdocs/gcc-9/changes.html,v retrieving revision 1.71 diff -u -r1.71 changes.html --- htdocs/gcc-9/changes.html 10 Jul 2019 13:03:55 -0000 1.71 +++ htdocs/gcc-9/changes.html 12 Jul 2019 15:55:47 -0000 @@ -58,6 +58,18 @@ </ul> </li> <li> + A change to the C++ <code>std::rotate</code> algorithm in GCC 9.1.0 can + cause ABI incompatibilities with object files compiled with other versions + of GCC. If the <code>std::rotate</code> algorithm is called with + an empty range then it might cause a divide-by-zero error + (as a <code>SIGFPE</code> signal) and crash. The change has been reverted + for GCC 9.2.0 and future releases. For more details see + <a href="https://gcc.gnu.org/bugzilla/show_bug.cgi?id=90920">Bug 90920</a>. + The problem can be avoided by recompiling any objects that might call + <code>std::rotate</code> with an empty range, so that the GCC 9.1.0 + definition of <code>std::rotate</code> is not used. + </li> + <li> The automatic template instantiation at link time (<a href="https://gcc.gnu.org/onlinedocs/gcc-9.1.0/gcc/C_002b_002b-Dialect-Options.html#index-frepo"><code>-frepo</code></a>) has been deprecated and will be removed in a future release. </li>