http://gcc.gnu.org/bugzilla/show_bug.cgi?id=46724
--- Comment #1 from Andreas Krebbel <krebbel at gcc dot gnu.org> 2010-11-30 14:37:39 UTC --- Compiling with GCC 4.5.2 (gcc version 4.5.2 20101108 (prerelease) [gcc-4_5-branch revision 166433] (GCC)) GDB returns "<value optimized out>" for 'a2' everywhere in function 'f'.