minimum_bad.py

import cffi

ffi = cffi.FFI()

ffi.cdef('''

struct bad_struct {
    uint64_t bad_uint64[2];
};

typedef struct bad_struct bad_struct_t;

static const uint64_t BAD_CONST;

bad_struct_t* bad_function(bad_struct_t* arg);

''')
lib = ffi.verify('''

struct bad_struct {
    uint64_t bad_uint64[2];
};

typedef struct bad_struct bad_struct_t;

static const uint64_t BAD_CONST = 1;

bad_struct_t*
bad_function(bad_struct_t* arg)
{
    arg->bad_uint64[0] = 1;
    arg->bad_uint64[1] = 1;
    return arg;
}

''')


def test(loop):
    BAD_CONST = ffi.cast('uint64_t', lib.BAD_CONST)
    bad_struct = ffi.new('bad_struct_t *')
    bad_struct = lib.bad_function(bad_struct)
    print bad_struct.bad_uint64[0], bad_struct.bad_uint64[1]

    if loop:
        for v in [BAD_CONST]:
            print bad_struct.bad_uint64[0], bad_struct.bad_uint64[1]
    else:
        print bad_struct.bad_uint64[0], bad_struct.bad_uint64[1]


test(False)
test(True)