I saw once a usage of the macro __unused which is explained here, but for some reason I can't find now where it is defined. Will appreciate help. I need it for an ansi C project. Thanks.
is GCC specific 6.32.1 Common Variable Attributes
This attribute, attached to a variable, means that the variable is meant to be possibly unused. GCC does not produce a warning for this variable.
NTERNATIONAL STANDARD ©ISO/IEC ISO/IEC 9899:201x does not even mention unused.