If a cast is to be used on any complex expression, the type of cast that may be applied is severely restricted. As explained in section 6.10, conversions on complex expressions are often a source of confusion and it is therefore wise to be cautious. In order to comply with these rules, it may be necessary to use a temporary variable and introduce an extra statement.

Example

... (float32_t)(f64a + f64b)              /* compliant     */
... (float64_t)(f32a + f32b)              /* not compliant */
... (float64_t)f32a                       /* compliant     */
... (float64_t)(s32a / s32b)              /* not compliant */
... (float64_t)(s32a > s32b)              /* not compliant */
... (float64_t)s32a / (float32_t)s32b     /* compliant     */
... (uint32_t)(u16a + u16b)               /* not compliant */
... (uint32_t)u16a + u16b                 /* compliant     */
... (uint32_t)u16a + (uint32_t)u16b       /* compliant     */
... (int16_t)(s32a - 12345)               /* compliant     */
... (uint8_t)(u16a * u16b)                /* compliant     */
... (uint16_t)(u8a * u8b)                 /* not compliant */
... (int16_t)(s32a * s32b)                /* compliant     */
... (int32_t)(s16a * s16b)                /* not compliant */
... (uint16_t)(f64a + f64b)               /* not compliant */
... (float32_t)(u16a + u16b)              /* not compliant */
... (float64_t)foo1(u16a + u16b)          /* compliant     */
... (int32_t)buf16a[u16a + u16b]          /* compliant     */