Add wording about output_data in case of output_size=0
@@ -418,14 +418,15 @@ struct evmc_result
* The memory containing the output data is owned by EVM and has to be
* freed with evmc_result::release().
*
- * This MAY be NULL.
+ * This pointer MAY be NULL.
+ * If evmc_result::output_size is 0 this pointer MUST NOT be dereferenced.
*/
const uint8_t* output_data;
/**
* The size of the output data.
*
- * If output_data is NULL this MUST be 0.
+ * If evmc_result::output_data is NULL this MUST be 0.
*/
size_t output_size;
