This PR fixes a SIGFPE crash on x86_64 when evaluating `INT_MIN / -1` or
`INT_MIN % -1` for signed integer types.
On x86_64, the `idiv` instruction traps when the quotient overflows the
destination register. For signed integers, `INT_MIN / -1` produces a
result that overflows (e.g., `-2147483648 / -1 = 2147483648` which
doesn't fit in Int32). ARM64's `sdiv` instruction wraps instead of
trapping.
The fix:
- For Int8/Int16/Int32: widen to the next larger type before
dividing/modding, then truncate back
- For Int64: explicitly check for the overflow case and return the
wrapped result
Fixes#11612🤖 Prepared with Claude Code
This PR implements a linter that warns when a deprecated coercion is
applied. It also warns when the `Option` coercion or the
`Subarray`-to-`Array` coercion is used in `Init` or `Std`. The linter is
currently limited to `Coe` instances; `CoeFun` instances etc. are not
considered.
The linter works by collecting the `Coe` instance declaration names that
are being expanded in `expandCoe?` and storing them in the info tree.
The linter itself then analyzes the info tree and checks for banned or
deprecated coercions.
This PR improves indexing for `grind` patterns. We now include symbols
occurring in nested ground patterns. This important to minimize the
number of activated E-match theorems.
This PR changes how match splitters are generated: Rather than rewriting
the match statement, the match compilation pipeline is used again.
The benefits are:
* Re-doing the match compilation means we can do more intelligent book
keeping, e.g. prove overlap assumptions only once and re-use the proof,
or prune the context of the MVar to speed up `contradiction`. This may
have allowed a different solution than #11200.
* It would unblock #11105, as the existing splitter implementation would
have trouble dealing with the matchers produced that way.
* It provides the necessary machinery also for source-exposed “none of
the above” bindings, a feature that we probably want at some point (and
we mostly need to find good syntax for, see #3136, although maybe I
should open a dedicated RFC).
* It allows us to skip costly things during matcher creation that would
only be useful for the splitter, and thus allows performance
improvements like #11508.
* We can drop the existing implementation.
It’s not entirely free:
* We have to run `simpH` twice, once for the match equations and once
for the splitter.
This PR adds recording functionality such that `shake` can more
precisely track whether an import should be preserved solely for its
`attribute` commands.
This PR lets recursive functions defined by well-founded recursion use a
different `fix` function when the termination measure is of type `Nat`.
This fix-point operator use structural recursion on “fuel”, initialized
by the given measure, and is thus reasonable to reduce, e.g. in `by
decide` proofs.
Extra provisions are in place that the fixpoint operator only starts
reducing when the fuel is fully known, to prevent “accidential” defeqs
when the remaining fuel for the recursive calls match the initial fuel
for that recursive argument.
To opt-out, the idiom `termination_by (n,0)` can be used.
We still use `@[irreducible]` as the default for such recursive
definitions, to avoid unexpected `defeq` lemmas. Making these functions
`@[semireducible]` by default showed performance regressions in lean.
When the measure is of type `Nat`, the system will accept an explicit
`@[semireducible]` without the usual warning.
Fixes#5234. Fixes: #11181.
This PR reduces the memory consumption of the language server (the
watchdog process in particular). In Mathlib, it reduces memory
consumption by about 1GB.
It also fixes two bugs in the call hierarchy:
- When an open file had import errors (e.g. from a transitive build
failure), the call hierarchy would not display any usages in that file.
Now we use the reference information from the .ilean instead.
- When a command would not set a parent declaration (e.g. `#check`), the
result was filtered from the call hierarchy. Now we display it as
`[anonymous]` instead.
This PR reverts https://github.com/leanprover/lean4/pull/11396, which
changed `set_library_suggestions` to create an auxiliary definition
marked with `@[library_suggestions]`, rather than storing `Syntax`
directly in the environment extension.
It wasn't tested properly.
Co-authored-by: Claude <noreply@anthropic.com>
This PR changes `set_library_suggestions` to create an auxiliary
definition marked with `@[library_suggestions]`, rather than storing
`Syntax` directly in the environment extension. This enables better
persistence and consistency of library suggestions across modules.
The change requires a stage0 update before tests can be restored. After
CI updates stage0, a follow-up PR will restore the test cases.
🤖 Generated with [Claude Code](https://claude.com/claude-code)
This PR implements new kinds of constraints for the `grind_pattern`
command. These constraints allow users to control theorem instantiation
in `grind`.
It requires a manual `update-stage0` because the change affects the
`.olean` format, and the PR fails without it.
This PR documents that `backward.*` options are only temporary
migration aids and may disappear without further notice after 6 months
after their introduction. Users are kindly asked to report if they rely
on these options.
This PR marks the automatically generated `sizeOf` theorems as `grind`
theorems.
closes#11259
Note: Requested update stage0, we need it to be able to solve example in
the issue above.
```lean
example (a: Nat) (b: Nat): sizeOf a < sizeOf (a, b) := by
grind
```
This PR replaces `MatcherInfo.numAltParams` with a more detailed data
structure that allows us, in particular, to distinguish between an
alternative for a constructor with a `Unit` field and the alternative
for a nullary constructor, where an artificial `Unit` argument is
introduced.
