Generates common zero-initialized definitions for tentative definitions.
Tentative definitions are declarations of variables with no storage class and no initializer.
-fno-common option generates individual zero-initialized definitions for
tentative definitions. These zero-initialized definitions are
placed in a ZI section in the generated object. Multiple
definitions in different files cause a
L6200E: Symbol multiply defined linker error because the individual
definitions clash with each other.
-fcommon option places the zero-initialized
definitions in a common block. This common definition is not
associated with any particular section or object, so multiple
definitions resolve to a single definition at link time.
The default is