http://gcc.gnu.org/bugzilla/show_bug.cgi?id=58244
--- Comment #2 from Martin Konôpka <martin.konopka at stuba dot sk> --- It it is confirmed, it is a very serious performance issue. In my test the code with the global declaration executed about 60000 times slower than the code with the local declaration. For people doing HPC this is a bug because it turns the compiled binary being unusable for codes affected by the issue. (60000 times slower is simply no go.) Large C codes often use global variables, otherwise the lists of function parameters would become enormously long.
