4.5.8. __attribute__((unused))

Normally, the compiler warns if a variable is declared but is never referenced. This attribute informs the compiler that you expect a variable to be unused and tells it not issue a warning if it is not used.


This variable attribute is a GNU compiler extension that is supported by the ARM compiler.


void Variable_Attributes_unused_0()
    static int aStatic =0;
    int aUnused __attribute__ ((unused));
    int bUnused;

In this example, the compiler warns that bUnused is declared but never referenced, but does not warn about aUnused.


The GNU compiler does not give any warning.

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