c - Struct with union: structure has no member named -

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• anonymous union within struct not in c99? 6 answers

i have following structures:

struct sched_param {     union {         int sched_priority;         struct lshort_sched_param lshort_params;     }; };  struct lshort_sched_param {     int requested_time;     int level; }; 

whenever make sched_param param1 structure , try update param1.sched_priority field message written in topic.

struct sched_param param1; param1.sched_priority = 1; 

but, whenever make sched_param param2 , try update param2.lshort_params.level works good.

struct sched_param param2; param2.lshort_params.level= 1; 

what reason?

it because version of gcc compiler using not support unnamed union. see stackoverflow link