UCALL_BUFFER_LEN
char test_str[UCALL_BUFFER_LEN + 10];
char expected_printf[UCALL_BUFFER_LEN]; \
char expected_assert[UCALL_BUFFER_LEN]; \
snprintf(expected_printf, UCALL_BUFFER_LEN, PRINTF_FMT_##ext, a, b); \
snprintf(expected_assert, UCALL_BUFFER_LEN, ASSERT_FMT_##ext, a, b); \
char buffer[UCALL_BUFFER_LEN];
guest_vsnprintf(uc->buffer, UCALL_BUFFER_LEN, fmt, va);
guest_vsnprintf(uc->buffer, UCALL_BUFFER_LEN, fmt, va);