btl/tcp: fix double list remove

[hjelmn]

This commit fixes an abort during finalize because pending events were
removed from the list twice.

References #2030

Signed-off-by: Nathan Hjelm [email protected]

[hjelmn]

@bosilca Found by MTT.

[bosilca]

Ah it is because opal_list_remove_first doesn't really mark the item as not on a list anymore. Good catch. 👍

[rhc54]

Should we update opal_list_remove_[] to update the item as no longer on a list? Feels a bit like a bug to me that it doesn't

[bosilca]

It does it on a DEBUG run, but not in an optimized one (it saves 2 stores). Whatever approach we take, we should standardize the behavior.

[rhc54]

I see - yeah, makes sense then that we don't update the item.

[hjelmn]

Yeah, it is an error to remove an item from a list twice since we try to keep the logic simple by not keeping track of the list. It would be a large change in behavior if opal_list_remove_item can be called twice on the same item without an append/prepend between.