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gcc
Fedora 15 comes with GCC 4.6.0 as primary compiler. Users will be able to experience compiled code improvements and use the newly added features, such as improved C++0x support, support for the Go language, REAL*16 support in Fortran, etc. Refer to http://gcc.gnu.org/gcc-4.6/changes.html and https://fedoraproject.org/wiki/Features/GCC46 for all user changes in it.