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Re: sizeof( function )

Not that is of great importance, but does anyone know why

int main( void )
{
        return printf( "%d\n", ( int )sizeof( main ) );
}

prints 1 ? :) 

It is invalid to use sizeof() with a function
type expression (C99 §6.5.3.4 para. 1) and hence this code invokes
undefined behavior.  gcc gives a warning if you compile with -pedantic,
but otherwise it apparently just returns 1;

See the description of -Wpointer-arith in the Fine Manual.


Segher

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