#include <stdio.h>

int main(void) {int x = 1; int x = 10; printf("%d\n", x);}

##</code><code>##

ben@feynman:/tmp$ cc x.c 
x.c: In function ‘main’:
x.c:3:33: error: redefinition of ‘x’
x.c:3:22: note: previous definition of ‘x’ was here