Not sure why they made this change, but the main address now redirects to an MPC-specific page.
Committed. Gerald Index: gcc-4.5/changes.html =================================================================== RCS file: /cvs/gcc/wwwdocs/htdocs/gcc-4.5/changes.html,v retrieving revision 1.116 diff -u -r1.116 changes.html --- gcc-4.5/changes.html 28 Feb 2017 10:09:46 -0000 1.116 +++ gcc-4.5/changes.html 4 Mar 2018 12:03:03 -0000 @@ -15,7 +15,7 @@ <ul> <li id="mpccaveat">GCC now requires the <a - href="http://www.multiprecision.org/">MPC</a> library in order to + href="http://www.multiprecision.org/mpc/">MPC</a> library in order to build. See the <a href="https://gcc.gnu.org/install/prerequisites.html">prerequisites page</a> for version requirements.</li>