View Compilation Error

0_0_2159702_32090.c: In function `main':
0_0_2159702_32090.c:4: error: `_int64' undeclared (first use in this function)
0_0_2159702_32090.c:4: error: (Each undeclared identifier is reported only once
0_0_2159702_32090.c:4: error: for each function it appears in.)
0_0_2159702_32090.c:4: error: syntax error before "a"