That's indeed usually the case. it's amusing that top down hates left recursion and bottom up hates right recursion (but it can cope), for similar reasons, different ends of a mathematical equator. Unfortunately I don't remember which thing failing prompted the increase for the Limbo version, but I suspect it was nested parenthesised expressions in a stress tester or similar, where given ( e it wanted to wait for the punchline. /sys/src/cmd/cc/cc.h defines YYMAXDEPTH to 1500 perhaps for a similar reason.
On Fri, 8 Aug 2025 at 16:28, Bruce Ellis <[email protected]> wrote: > If you are blowing YYMAXDEPTH then you have a poor grammar specification. > > Items : items item > > Is good. > > Items : item items > > Is poor. > > On Thu, 7 Aug 2025, 5:40 am , <[email protected]> wrote: > >> Quoth Anthony Sorace <[email protected]>: >> > I've just run into awk code where yacc's default YYMAXDEPTH of 150 >> causes stack exhaustion; increasing it lets the code work fine. It's been >> 150 since at least v7 Unix (I didn't have earlier on hand to check), and >> our systems are a little bigger now; it seems safe to bump up quite a bit. >> > >> > Is anyone aware of yacc-generated code which uses this value as a >> check, rather than just being the more obvious guard against using too much >> system resources? >> > >> > >> >> I don't think anything would notice. Do you have an example of code that >> causes an issue? >> > *9fans <https://9fans.topicbox.com/latest>* / 9fans / see discussions > <https://9fans.topicbox.com/groups/9fans> + participants > <https://9fans.topicbox.com/groups/9fans/members> + delivery options > <https://9fans.topicbox.com/groups/9fans/subscription> Permalink > <https://9fans.topicbox.com/groups/9fans/Td74874a3700432ac-M162a320121497030076cce59> > ------------------------------------------ 9fans: 9fans Permalink: https://9fans.topicbox.com/groups/9fans/Td74874a3700432ac-M468c4f01b70986c11457df8d Delivery options: https://9fans.topicbox.com/groups/9fans/subscription
