Non-tail recursive Hashtable find_all function

[aschahar]

The Hashtbl.find_all function implementation is not tail recursive. Due to this, stack overflow occurs for a big set of the data.

[gasche]

See #4747 for previous work on making Hashtbl functions tail-recursive. It's a lot of subtle work that generally degrades the performance of the use-cases most users care about. Personally I decided to wait until tail-recursion-modulo-cons is available in the compiler (see #181), which would let us write not-unnatural tail-recursive code.

[wizeman]

Perhaps a warning could be added to the documentation in the mean time? Otherwise, non-experts might run into unpleasant surprises...
The List module seems to have functions flagged as non-tail recursive...

[github-actions]

This issue has been open one year with no activity. Consequently, it is being marked with the "stale" label. What this means is that the issue will be automatically closed in 30 days unless more comments are added or the "stale" label is removed. Comments that provide new information on the issue are especially welcome: is it still reproducible? did it appear in other contexts? how critical is it? etc.

[gasche]

We made some progress on tail-modulo-cons optimizations ( #9760 ); if one of the implements would get merged, we would have an easy way to make this function tail-recursive without noticeable performance loss.

[github-actions]

This issue has been open one year with no activity. Consequently, it is being marked with the "stale" label. What this means is that the issue will be automatically closed in 30 days unless more comments are added or the "stale" label is removed. Comments that provide new information on the issue are especially welcome: is it still reproducible? did it appear in other contexts? how critical is it? etc.

[gasche]

Reopening: it should be easy, now that TRMC has been integrated, to make find_all tail-recursive, but this will have to wait for 5.x.