eclipse-cyclonedds
Crash in typebuilder_type_fini() at src\core\ddsi\src\ddsi_typebuilder.c:226
Hi ,
I want to try using example/dynsub to subscribe to a topic with keywords(wchar), Then dynsub will crash.
Are you sure you need wchar? I suspect the crash has something to do with that, IINM we don't support wchar fully.
Anyway, a double free is always a bad bug. Do you have a stack trace where it crashes or at least whether it crashes in dynsub or in the libddsc.so? Or even better, a minimal reproducer?
I found the problem: unsupport type was freed twice. The first free was in ddsi_typebuilder.c:534, if type is UNSUPPORTED it will call typebuilder_type_fini() when get_topic_descriptor(). https://github.com/eclipse-cyclonedds/cyclonedds/blob/4ece3334a608a7f983b9694d5ff3b9b23c6af5cf/src/core/ddsi/src/ddsi_typebuilder.c#L534
The second time was in calling typebuilder_data_free(). https://github.com/eclipse-cyclonedds/cyclonedds/blob/4ece3334a608a7f983b9694d5ff3b9b23c6af5cf/src/core/ddsi/src/ddsi_typebuilder.c#L1889
The reason is : the pointer is not set null after memory is freed in my environment.
I think there are two solutions:
- delete first free in in ddsi_typebuilder.c:534;
- set pointer=null after free in ddsi_typebuilder.c:236; https://github.com/eclipse-cyclonedds/cyclonedds/blob/4ece3334a608a7f983b9694d5ff3b9b23c6af5cf/src/core/ddsi/src/ddsi_typebuilder.c#L236
Which you think is more appropriate, or you have a better solution？