The C++ implementation of the fixedpoint engine (in
z3/src/api/api_datalog.cpp) already attempts to read `rlimit` from its
local parameters:
```c++
unsigned rlimit = to_fixedpoint(d)->m_params.get_uint("rlimit", mk_c(c)->get_rlimit());
```
However, because `rlimit` was not registered in the public fp parameter
schema (`fp_params.pyg`), any attempt by clients to set it locally via
`Z3_fixedpoint_set_params` was rejected by the Z3 parameter validator
with an "unknown parameter" error.
Implements the algorithm of Eq(p,q) = Empty(p XOR q)' using a union-find
driven bisimulation closure (per the CAV'26 ERE paper).
### What's added
* **New primitive OP_RE_XOR (re.xor)** wired through seq_decl_plugin:
parser signature, info propagation (nullable, min_length), and
pretty-printer.
* **seq_rewriter**: structural XOR rewrites ( XOR r = empty, XOR empty =
r, ull XOR r = comp(r), comp/comp absorption, complement push, AC
normalisation), nullability (Null(p XOR q) = Null(p) != Null(q)),
derivative (D_a(p XOR q) = D_a(p) XOR D_a(q)), reverse, antimirov
derivative, and `check_deriv_normal_form` coverage.
* **New class seq::regex_bisim** in
`src/ast/rewriter/seq_regex_bisim.{h,cpp}` to keep the bisim logic out
of the already-large `seq_rewriter.cpp`. Uses `basic_union_find` from
`util/union_find.h`, an `obj_map` for the node assignment, and a
50000-step bound (returns `l_undef` on overrun).
* **Integration** in `seq_rewriter::reduce_re_eq` (with a re-entry
guard) and in `seq_regex::propagate_eq` / `propagate_ne` for ground
regexes; on `l_undef` we fall back to the existing axiomatisation.
* **`sls_seq_plugin`**: extend `OP_RE_DIFF` switch arms to also cover
`OP_RE_XOR`.
### Validation
* Full release build with MSVC + Ninja.
* `./test-z3 /a` -- 89/89 tests passing.
* `./test-z3 /seq smt2print_parse` -- PASS.
* Smoke tests with `(a|b)*` vs `(a*b*)*` (equal) and `a*` vs `(a|b)*`
(not equal) return the expected `sat`/`unsat` quickly.
---------
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
Bumps [shell-quote](https://github.com/ljharb/shell-quote) from 1.7.3 to
1.8.4.
<details>
<summary>Changelog</summary>
<p><em>Sourced from <a
href="https://github.com/ljharb/shell-quote/blob/main/CHANGELOG.md">shell-quote's
changelog</a>.</em></p>
<blockquote>
<h2><a
href="https://github.com/ljharb/shell-quote/compare/v1.8.3...v1.8.4">v1.8.4</a>
- 2026-05-22</h2>
<h3>Commits</h3>
<ul>
<li>[Fix] <code>quote</code>: validate object-token shapes <a
href="4378a6e613"><code>4378a6e</code></a></li>
<li>[Dev Deps] update <code>@ljharb/eslint-config</code>,
<code>auto-changelog</code>, <code>eslint</code>, <code>npmignore</code>
<a
href="22ebec0434"><code>22ebec0</code></a></li>
<li>[Tests] increase coverage <a
href="9f3caa3190"><code>9f3caa3</code></a></li>
<li>[readme] replace runkit CI badge with shields.io check-runs badge <a
href="3344a047dd"><code>3344a04</code></a></li>
<li>[Dev Deps] update <code>@ljharb/eslint-config</code> <a
href="699c5113d1"><code>699c511</code></a></li>
</ul>
<h2><a
href="https://github.com/ljharb/shell-quote/compare/v1.8.2...v1.8.3">v1.8.3</a>
- 2025-06-01</h2>
<h3>Fixed</h3>
<ul>
<li>[Fix] remove unnecessary backslash escaping in single quotes <a
href="https://redirect.github.com/ljharb/shell-quote/issues/15"><code>[#15](https://github.com/ljharb/shell-quote/issues/15)</code></a></li>
</ul>
<h2><a
href="https://github.com/ljharb/shell-quote/compare/v1.8.1...v1.8.2">v1.8.2</a>
- 2024-11-27</h2>
<h3>Fixed</h3>
<ul>
<li>[Fix] <code>quote</code>: preserve empty strings <a
href="https://redirect.github.com/ljharb/shell-quote/issues/18"><code>[#18](https://github.com/ljharb/shell-quote/issues/18)</code></a></li>
</ul>
<h3>Commits</h3>
<ul>
<li>[meta] fix changelog tags <a
href="0fb9fd8441"><code>0fb9fd8</code></a></li>
<li>[actions] split out node 10-20, and 20+ <a
href="819bd842e0"><code>819bd84</code></a></li>
<li>[Dev Deps] update <code>@ljharb/eslint-config</code>,
<code>auto-changelog</code>, <code>npmignore</code>, <code>tape</code>
<a
href="fc564086c8"><code>fc56408</code></a></li>
<li>[actions] update npm for windows tests <a
href="fdeb0fd102"><code>fdeb0fd</code></a></li>
<li>[Dev Deps] update <code>@ljharb/eslint-config</code>,
<code>aud</code>, <code>tape</code> <a
href="b8a4a3b3f5"><code>b8a4a3b</code></a></li>
<li>[actions] prevent node 14 on ARM mac from failing <a
href="9eecafc048"><code>9eecafc</code></a></li>
<li>[meta] exclude more files from the package <a
href="4044e7fad4"><code>4044e7f</code></a></li>
<li>[Tests] replace <code>aud</code> with <code>npm audit</code> <a
href="8cfdbd8ec3"><code>8cfdbd8</code></a></li>
<li>[meta] add missing <code>engines.node</code> <a
href="843820e1a4"><code>843820e</code></a></li>
<li>[Dev Deps] add missing peer dep <a
href="4c3b88d792"><code>4c3b88d</code></a></li>
<li>[Dev Deps] pin <code>jackspeak</code> since 2.1.2+ depends on npm
aliases, which kill the install process in npm < 6 <a
href="80322ed591"><code>80322ed</code></a></li>
</ul>
<h2><a
href="https://github.com/ljharb/shell-quote/compare/v1.8.0...v1.8.1">v1.8.1</a>
- 2023-04-07</h2>
<h3>Fixed</h3>
<ul>
<li>[Fix] <code>parse</code>: preserve whitespace in comments <a
href="https://redirect.github.com/ljharb/shell-quote/issues/6"><code>[#6](https://github.com/ljharb/shell-quote/issues/6)</code></a></li>
<li>[Fix] properly support the <code>escape</code> option <a
href="https://redirect.github.com/ljharb/shell-quote/issues/5"><code>[#5](https://github.com/ljharb/shell-quote/issues/5)</code></a></li>
</ul>
<h3>Commits</h3>
<ul>
<li>[Refactor] <code>parse</code>: hoist <code>getVar</code> to module
level <a
href="b42ac73e39"><code>b42ac73</code></a></li>
<li>[Refactor] hoist some vars to module level <a
href="8f0c5c3c9d"><code>8f0c5c3</code></a></li>
<li>[Refactor] <code>parse</code>: use <code>slice</code> over
<code>substr</code>, cache some values <a
href="fcb2e1acd5"><code>fcb2e1a</code></a></li>
<li>[Refactor] <code>parse</code>: a bit of cleanup <a
href="6780ec5194"><code>6780ec5</code></a></li>
<li>[Refactor] <code>parse</code>: tweak the regex to not match nothing
<a
href="227d4742a0"><code>227d474</code></a></li>
</ul>
<!-- raw HTML omitted -->
</blockquote>
<p>... (truncated)</p>
</details>
<details>
<summary>Commits</summary>
<ul>
<li><a
href="ff166e2b63"><code>ff166e2</code></a>
v1.8.4</li>
<li><a
href="4378a6e613"><code>4378a6e</code></a>
[Fix] <code>quote</code>: validate object-token shapes</li>
<li><a
href="22ebec0434"><code>22ebec0</code></a>
[Dev Deps] update <code>@ljharb/eslint-config</code>,
<code>auto-changelog</code>, <code>eslint</code>, `npmig...</li>
<li><a
href="9f3caa3190"><code>9f3caa3</code></a>
[Tests] increase coverage</li>
<li><a
href="3344a047dd"><code>3344a04</code></a>
[readme] replace runkit CI badge with shields.io check-runs badge</li>
<li><a
href="699c5113d1"><code>699c511</code></a>
[Dev Deps] update <code>@ljharb/eslint-config</code></li>
<li><a
href="487a9b41a7"><code>487a9b4</code></a>
v1.8.3</li>
<li><a
href="01faafff97"><code>01faaff</code></a>
[Fix] remove unnecessary backslash escaping in single quotes</li>
<li><a
href="b19fc77e66"><code>b19fc77</code></a>
v1.8.2</li>
<li><a
href="59d29ea694"><code>59d29ea</code></a>
[Fix] <code>quote</code>: preserve empty strings</li>
<li>Additional commits viewable in <a
href="https://github.com/ljharb/shell-quote/compare/v1.7.3...v1.8.4">compare
view</a></li>
</ul>
</details>
<details>
<summary>Maintainer changes</summary>
<p>This version was pushed to npm by <a
href="https://www.npmjs.com/~ljharb">ljharb</a>, a new releaser for
shell-quote since your current version.</p>
</details>
<details>
<summary>Install script changes</summary>
<p>This version adds <code>prepublish</code> script that runs during
installation. Review the package contents before updating.</p>
</details>
<br />
[](https://docs.github.com/en/github/managing-security-vulnerabilities/about-dependabot-security-updates#about-compatibility-scores)
Dependabot will resolve any conflicts with this PR as long as you don't
alter it yourself. You can also trigger a rebase manually by commenting
`@dependabot rebase`.
[//]: # (dependabot-automerge-start)
[//]: # (dependabot-automerge-end)
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You can trigger Dependabot actions by commenting on this PR:
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You can disable automated security fix PRs for this repo from the
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Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
This bug was discovered by claude analyzing the descrepency of outputs
in https://github.com/Z3Prover/bench/discussions/2516. The benchmark was
edited - a line required stats was commented out - and this exposed the
scanner inconsistent behavior.
read_comment and read_multiline_comment handled end-of-line newlines as
new_line(); next();, the reverse of the main scan() loop's next();
new_line();. This left m_spos one higher on the line following a
comment, shifting every reported column on that line by +1 (e.g. a (pop)
error reported column 5 instead of 4 when the previous line was a
comment). Reorder both comment readers to match scan() so column numbers
are consistent regardless of whether the preceding line is a comment.
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
`seq_rewriter.cpp` was missing several regex-concat normalizations
around `re.all` (`Σ*`), causing avoidable growth and missed
simplifications. This update fills the four gaps: nullable absorption,
guarded union distribution, intersection suffix elimination, and
nested-star collapse.
- **Nullable/full-seq absorption (A1)**
- Generalizes `Σ*·R → Σ*` and `R·Σ* → Σ*` beyond `Σ*·Σ*`.
- Applies when `R` is interpreted, nullable, and has `min_length = 0`.
- **Guarded distribution over union (A2)**
- Adds `Σ*·(R1 ∪ R2)` distribution when at least one arm is already
`Σ*`-headed.
- Rebuilds via normalized union so the redundant arm collapses to `Σ*`.
- **Intersection + full-seq tail elimination (A3)**
- Adds `(R1 ∩ … ∩ Rn)·Σ* → (R1 ∩ … ∩ Rn)` when every intersection leaf
already ends in `Σ*`.
- **Nested star concat collapse (A4)**
- Adds `R*·(R*·X) → R*·X`, covering non-adjacent star patterns not
handled by the prior adjacent-only rewrite.
```cpp
if (re().is_full_seq(a) && accepts_empty_word(b)) result = a; // A1
if (re().is_full_seq(a) && re().is_union(b, u1, u2) && ...) ... // A2
if (re().is_intersection(a, u1, u2) && re().is_full_seq(b) && ...) result=a; // A3
if (re().is_star(a, a1) && re().is_concat(b, b1, b2) && re().is_star(b1,b3) && a1==b3) result=b; // A4
```
Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>
Fixes#9022.
## Problem
After a `(push)`, Z3 could incorrectly report `unsat` for satisfiable
FPA formulas in which an uninterpreted function returns a floating-point
value (e.g. `int_to_fp`). The example in #9022 has a single `push` and a
single `check-sat` (no `pop`), so the `m_rw.reset()` added in
`pop_scope_eh` by #8712 does not apply.
## Root cause
`theory_fpa` lazily converts FP constraints to bit-vectors and asserts
the equivalences/side conditions as **unit theory axioms**
(`assert_cnstr` → `mk_th_axiom`, which `assign`s the literal at the
current decision level).
For `fp.to_*` terms (`fp.to_real`, `fp.to_ubv`, …) the conversion
equality and side conditions are emitted **only** in
`internalize_term()`, which runs exactly once. The `else if` branch for
fpa-family conversion terms in `relevant_eh` previously did nothing.
These unit axioms are level-local: on DPLL backtracking the assignment
is undone, but `internalize_term()` is not re-run for the
already-internalized term (in particular when the term lives at the
user-`push` base level, where its clause is not a reinit clause). The
side conditions include the axioms linking FP uninterpreted functions to
their bit-vector counterparts (`int_to_fp(i) =
fp(extract(int_to_fp_bv(i)))`). Once lost, `int_to_fp_bv` becomes
unconstrained, enabling an unsound `unsat`. This is exactly the behavior
described in #8345/#9022 (and why the result flips with vs. without
`push`).
## Fix
`relevant_eh` re-fires on relevancy re-propagation after a backtrack.
Re-emit the conversion equality and side conditions for `fp.to_*` terms
there, mirroring `internalize_term`, so the FP↔BV linking axioms stay in
force across backtracking. On an `m_conversions` cache hit this just
re-asserts the (hash-consed) conversion equality and a `true` side
condition, so it adds no new terms and no clause bloat. The change only
adds sound constraints, so it can never turn a satisfiable formula
`unsat`.
## Validation
- #9022 reproducer: no longer reports `unsat` across many random seeds
and longer timeouts; a model (`sat`) is still found (the problem is
inherently hard quantified FP + nonlinear arithmetic, so timeouts are
expected).
- #8345 reproducer: first `check-sat` still `unsat` (the negated
quantifier axiom is valid).
- Additional incremental push/pop FP cases with
`fp.to_real`/`fp.add`/`fp.sub` and FP-returning UFs: correct, consistent
results.
- `test-z3 /a`: all 89 unit tests pass.
- Debug build (soundness assertions enabled): no assertion failures on
the above cases.
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
MSVC ASan reports showed a container-overflow in LP tableau pivoting,
reproducible from both examples and solver tests (issue #9781). The
failure came from reading a `column_cell` through a reference after
pivoting removed that entry from the backing column.
- **Root cause**
- `pivot_column_tableau` and the analogous Diophantine elimination loop
both held `auto& c = column.back()` across a call
(`pivot_row_to_row_given_cell`) that immediately removes that very cell
from the column via `remove_element`.
- After the mutation, the subsequent read `c.var()` used for bookkeeping
observed invalid memory.
- **Change**
- Record the affected row in the bookkeeping set (`m_touched_rows` /
`m_changed_rows`) by reading `c.var()` **before** the pivot call, while
the back cell is still valid.
- Make `static_matrix::pivot_row_to_row_given_cell` return `void`
instead of `bool`. Its result (`!rowii.empty()`) was always `true`: both
callers keep the matrix at full row rank (the tableau basis columns form
an identity submatrix; the Diophantine `m_l_matrix` stays invertible),
so an elementary row operation can never empty a row. The dead `if
(!...) return false;` early-exit in `pivot_column_tableau` is removed
and replaced with a `SASSERT(!rowii.empty())` documenting the invariant.
- **Affected code paths**
- `src/math/lp/static_matrix.h`, `src/math/lp/static_matrix.cpp`,
`src/math/lp/static_matrix_def.h`
- `src/math/lp/lp_core_solver_base_def.h`
- `src/math/lp/dioph_eq.cpp`
- **Behavioral impact**
- No algorithmic change to pivoting.
- Removes the stale-reference hazard in the loops that repeatedly
eliminate entries from a column.
```c++
while (column.size() > 1) {
auto& c = column.back();
SASSERT(c.var() != piv_row_index);
if (m_touched_rows != nullptr)
m_touched_rows->insert(c.var());
m_A.pivot_row_to_row_given_cell(piv_row_index, c, j);
}
```
- **Verification**
- Reproduced the exact issue #9781 failure on a local ASan build
(`container-overflow` in `pivot_column_tableau`) using the pre-fix code,
and confirmed it is gone with this change.
- The 4 reported tests pass clean under ASan: `c_example`,
`cpp_example`, `test-z3 get_implied_equalities`, `test-z3 quant_solve`.
- Full `test-z3 /a` suite: 89 passed, 0 failed, 0 ASan errors.
---------
Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>
Co-authored-by: Nikolaj Bjorner <nbjorner@microsoft.com>
Co-authored-by: Lev Nachmanson <levnach@hotmail.com>
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
