On 13/01/2021 11.25, David Hildenbrand wrote:
On 12.01.21 14:20, Janosch Frank wrote:Let's make it clear that there is something at the end of the struct. The exact offset is reported by the cpu_offset member. Signed-off-by: Janosch Frank <frankja@xxxxxxxxxxxxx> --- lib/s390x/sclp.h | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/lib/s390x/sclp.h b/lib/s390x/sclp.h index dccbaa8..395895f 100644 --- a/lib/s390x/sclp.h +++ b/lib/s390x/sclp.h @@ -134,7 +134,10 @@ typedef struct ReadInfo { uint8_t reserved7[134 - 128]; uint8_t byte_134_diag318 : 1; uint8_t : 7; - struct CPUEntry entries[0]; + /* + * The cpu entries follow, they start at the offset specified + * in offset_cpu. + */I mean, that's just best practice. At least when I spot "[0];" and the end of a struct, I know what's happening. No strong opinion about the comment, I wouldn't need it to understand it.
The problem is that the "CPUEntry" entries either might be at this location, or later, so the entries[0] can be misleading. You always have to go via the offset_cpu field to find the right location.
Thomas
