Tail-call optimization in C is relatively recent
The C calling convention has been that the callee does not remove any stuff the caller has put on the stack. The caller could see the declaration int f();, the actual call could have n>0 arguments, and the actual function could have m≤n parameters. That would not always work if the callee removed the arguments.
- ▪The C calling convention has been that the callee does not remove any stuff the caller has put on the stack.
- ▪The caller could see the declaration int f();, the actual call could have n>0 arguments, and the actual function could have m≤n parameters.
- ▪That would not always work if the callee removed the arguments.
Hacker News (Front Page) files mainly under programming. We currently carry 1,352 of its stories. Top-voted stories on Hacker News.
Story provenance
Source · retrieval · rights · ranking — open for full record
inspect →
Story provenance
Attribution is not the same as permission. This drawer separates discovery metadata, excerpts, WeSearch-generated summaries, reuse status, and whether the publisher receives the visit. Nothing here claims a legal grant the publisher has not made.
Record
| Original publisher | Lwn |
| Canonical URL | https://lwn.net/Articles/1034703/ |
| Publication time | Mon, 10 Aug 2026 11:34:40 +0000 |
| Retrieval time | 2026-08-10T11:55:46.090Z |
| Last seen | 2026-08-10T11:55:46.090Z |
| Headline source | Publisher (no WeSearch rewrite) |
| Excerpt source | publisher body |
| Excerpt method | First ~120 words (~800 chars) of extracted publisher body, fair-use limited. |
| Summary | WeSearch · cerebras-chat (WeSearch summarizer) |
| Summary source text | contentText |
| Citation coverage | Summary is a WeSearch-generated derivative; primary citation is the original publisher URL. |
| Cluster | RR6kw203fO14 · 1 stories |
| Cluster logic | Grouped by semantic title/content similarity across sources within a rolling window. Same-publisher template collisions are excluded from coverage comparison. |
| Ranking reason | Story pages are not engagement-ranked. Hub feeds use recency, with optional source-diversified chronological ordering (cap consecutive stories per source). No personalized ranking. |
| Publisher visit | Yes — open original |
| Substitutes article? | No — link-out required for full text |
Rights status (four layers)
WeSearch handling by dimension
| Indexing | May the item be indexed (stored, ranked, made findable)? | Allowed |
| Snippet | May a short excerpt of the publisher's text be shown? | Allowed |
| AI summary | May WeSearch generate its own short summary of the article? | Limited |
| Retrieval / RAG | May the content be exposed for third-party retrieval-augmented generation? | Not asserted |
| Model training | May the content be used to train AI models? | Not asserted |
| Commercial reuse | May the content be reused commercially? | Not permitted |
Basis: Derived from the published RSS/Atom feed. Contact: [email protected]. Reviewed: 2026-07-24.
Opening excerpt (first ~120 words) tap to expand
Tail-call optimization in C is relatively recent Posted Aug 21, 2025 22:11 UTC (Thu) by anton (subscriber, #25547) Parent article: Python, tail calls, and performance Actually tail calls in C have not been around forever. The C calling convention has been that the callee does not remove any stuff the caller has put on the stack. The caller could see the declaration int f();, the actual call could have n>0 arguments, and the actual function could have m≤n parameters. That would not always work if the callee removed the arguments. So the caller had to remove the arguments between the call and the following return, turning the call into a non-tail call. When I looked in 1994 at the C compilers of the day, they did not perform tail-call optimization for the kind of usage shown in the article.
…
Excerpt limited to ~120 words for fair-use compliance. The full article is at Lwn.
Discussion
0 commentsMore from Lwn
