foo.c: In function 'main':
foo.c:5:2: error: unknown type name '_int64'
foo.c:6:2: error: unknown type name '_int64'
foo.c:10:2: warning: format '%I64d' expects argument of type 'long long int *', but argument 2 has type 'int *' [-Wformat]
foo.c:13:3: warning: format '%I64d' expects argument of type 'long long int *', but argument 2 has type 'int *' [-Wformat]
foo.c:14:3: warning: format '%I64d' expects argument of type 'long long int', but argument 2 has type 'int' [-Wformat]