Lean 4 fork for HoTT-compatible kernel extensions (Path types, transport, HITs). Maintained against upstream leanprover/lean4.
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Henrik Böving 332c1ec46a
perf: specializer a little more courageously (#12239)
This PR reverts a lot of the changes done in #8308. We practically
encountered situations such as:
```
fun y (z) :=
  let x := inst
  mkInst x z
f y
```
Where the instance puller turns it into:
```
let x := inst
fun y (z) :=
  mkInst x z
f y
```
The current heuristic now discovers `x` being in scope at the call site
of `f` and being used under a binder in `y` and thus blocks pulling in
`x` to the specialization, abstracting over an instance.

According to @zwarich this was done at the time either due to observed
stack overflows or pulling in computation into loops. With the current
configuration for abstraction in specialization it seems rather unlikely
that we pull in a non trivial computation into a loop with this. We also
practically didn't observe stack overflows in our tests or benchmarks.
Cameron speculates that the issues he observed might've been fixed
otherwise by now.

Crucial note: Deciding not to abstract over ground terms *might* cause
us to pull in computationally intensive ground terms into a loop. We
could decide to weaken this to just instance terms though of course even
computing instances might end up being non-trivial.
2026-01-30 08:23:15 +00:00
.claude doc: add changelog label instructions to CLAUDE.md (#12227) 2026-01-29 03:24:23 +00:00
.github fix: verify PR release artifacts before creating tags (#12223) 2026-01-29 04:41:11 +00:00
doc doc: clarify release notes title format requirements (#12182) 2026-01-27 08:08:47 +00:00
images
releases_drafts chore: add release draft for the module system (#11359) 2025-11-26 15:01:07 +00:00
script chore: reformat all cmake files (#12218) 2026-01-28 18:23:08 +00:00
src perf: specializer a little more courageously (#12239) 2026-01-30 08:23:15 +00:00
stage0 perf: specializer a little more courageously (#12239) 2026-01-30 08:23:15 +00:00
tests perf: specializer a little more courageously (#12239) 2026-01-30 08:23:15 +00:00
.gitattributes doc: grove: update and add String data (#11551) 2025-12-08 16:49:37 +00:00
.gitignore chore: add .vscode/settings.json to .gitignore (#10795) 2025-10-16 07:08:41 +00:00
.gitpod.Dockerfile chore: add gitpod configuration (#6382) 2024-12-15 21:38:13 +00:00
.gitpod.yml chore: add gitpod configuration (#6382) 2024-12-15 21:38:13 +00:00
.ignore chore: ignore stage0/ (for rg etc.) 2022-03-18 15:28:20 +01:00
CMakeLists.txt chore: reformat all cmake files (#12218) 2026-01-28 18:23:08 +00:00
CMakePresets.json chore: CI: enable leak sanitizer again (#11339) 2025-11-27 18:32:35 +00:00
CODEOWNERS chore: make @hargoniX code owner of the compiler (#10732) 2025-10-10 04:43:38 +00:00
CONTRIBUTING.md doc: triage 2024-07-26 18:24:06 +02:00
flake.lock chore: robustify Nix shell (#8141) 2025-04-28 15:08:32 +00:00
flake.nix chore: use lld if available for building core (#10694) 2025-10-08 16:47:30 +00:00
lean-toolchain doc: VS Code dev setup (#2961) 2023-11-30 08:35:03 +00:00
lean.code-workspace chore: lean.code-workspace: fix terminal cwd (#10802) 2025-10-16 20:19:12 +00:00
LICENSE chore: remove LICENSE header that confused GitHub 2021-11-18 09:42:35 +01:00
LICENSES feat: ship cadical (#4325) 2024-08-23 09:13:27 +00:00
README.md doc: update URLs that are currently pointing to redirects (#10397) 2025-09-17 15:50:07 +00:00
RELEASES.md chore: updates to release_checklist.md (#7817) 2025-04-04 03:45:36 +00:00

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