View Compilation Error

0_0_22314957_13496.c: In function 'plusll':
0_0_22314957_13496.c:13:5: error: 'for' loop initial declarations are only allowed in C99 or C11 mode
     for(int i=54; i>=0; i--)
     ^
0_0_22314957_13496.c:13:5: note: use option -std=c99, -std=gnu99, -std=c11 or -std=gnu11 to compile your code
0_0_22314957_13496.c: At top level:
0_0_22314957_13496.c:22:1: error: expected ')' at end of input
 void multiplus(in
 ^