The 4.4.2 documentation states that the -fno-common option "specifies that the compiler should place uninitialized global variables in the __data__ section of the object file".
This is different from action, where -fno-common forces gcc to place uninitialized global variables in the BSS section of the object file. -- Summary: -fno-common documentation inaccuracy Product: gcc Version: 4.4.2 Status: UNCONFIRMED Severity: minor Priority: P3 Component: c AssignedTo: unassigned at gcc dot gnu dot org ReportedBy: darwish dot 07 at gmail dot com http://gcc.gnu.org/bugzilla/show_bug.cgi?id=42726