5.9 and static function or global variable

[xiangke]

As we know, static function or global variable has only internal linkage, is invisible for other module,
Why their name can not be defined as same as ones in other translation unit?
For example, below case :
/*tunit1.c*/
static int8_t count;
static void foo ( void )
{
}

/*tunit2.c*/
static int8_t count;
static void foo ( void )
{
}