Hi! F14 now has gcc-4.5-RH compiler instead of 4.4-RH. For the changes (especially user visible ones), see http://gcc.gnu.org/gcc-4.5/changes.html (though the list contains even many features that have been backported to 4.4-RH. I had to backport even over 100 of changes that were backported to 4.4-RH from trunk already, but aren't on 4.5 branch). Unless using decimal float, the compiler should be ABI compatible with 4.4-RH, including the libraries (which ought to be backwards compatible). If you experience any internal compiler errors or other compiler bugs, please file them into bugzilla. Please don't rely on LTO in 4.5, it is not mature enough (especially -fwhopr is completely unusable, -flto only barely so), things will get better in GCC 4.6. Jakub -- devel mailing list devel@xxxxxxxxxxxxxxxxxxxxxxx https://admin.fedoraproject.org/mailman/listinfo/devel