Message        An initializer list without an expression is not
                valid.  The compiler will replace the empty
                expression with the constant 0.

 Description    The C standard requires that an initializer list
                contain an expression.  The compiler has encountered
                one without an expression.  The compiler will treat
                the empty list ({}) as if it contained a single zero
                ({0}).  This is for compatibility with some other C
                compilers.  Be aware that this syntax may not be
                accepted by other C compilers.

 User Action    Supply an expression to the initializer.