Bump wasm-cxx-shim to v0.4.0-alpha.1, drop wasm-uu ray_cast cfg-gates

The shim's v0.4.0-alpha.1 release moves its tested manifold pin to
upstream main HEAD (`5f95a3ac`), the same commit our host build pins.
That means the wasm-uu lane now sees the same C API surface as host —
including ray_cast, which we cfg-gated off in 0.1.7 / 3.4.106 because
the previous shim (v0.3.0) defaulted to the v3.4.1 pin and didn't
have it. The gates can drop now.

The shim is alpha because it carries a single vendored diff of
upstream manifold#1690 (the PR that adds `MANIFOLD_NO_IOSTREAM`
natively). When #1690 merges, the shim re-cuts as non-alpha v0.4.0
and the carry-patch goes away. The alpha pin SHA is encoded in the
tag itself (`v0.4.0-alpha.1+5f95a3ac`) for explicit lockstep.

Changes:
- `crates/manifold-csg-sys/build.rs`: WASM_CXX_SHIM_TAG → `v0.4.0-alpha.1+5f95a3ac`.
- Drop the `#[cfg(not(all(target_arch = "wasm32", target_os = "unknown")))]`
  gates introduced in 0.1.7 / 3.4.106:
  - sys: `ManifoldRayHitVec`, `ManifoldRayHit`, `manifold_ray_hit_vec_size`,
    `manifold_alloc_ray_hit_vec`, `manifold_destruct_ray_hit_vec`,
    `manifold_delete_ray_hit_vec`, `manifold_ray_cast`,
    `manifold_ray_hit_vec_length`, `manifold_ray_hit_vec_get`
  - safe: `pub mod ray`, `pub use ray::RayHit`, `Manifold::ray_cast`
  - tests: `ray_cast_through_cube`, `ray_cast_miss`, `ray_cast_hit_has_normal`
- `wasm32-uu/CMakeLists.txt`: comment updated.
- `CLAUDE.md`: "Pin / shim follow-ups" updated to note ray_cast is no
  longer gated.
- `.claude/skills/deep-review/SKILL.md`: matching update in section 10.
- `docs/plans/wasm-unknown-unknown.md`: shim version bumped.

Versions for the next release:
  manifold-csg-sys 3.4.106 → 3.4.107
  manifold-csg     0.1.7   → 0.1.8
  manifold3d-sys / manifold3d facades follow lockstep `=` pins.

Verified:
- 214 host integration tests pass (3 ray_cast tests run on host as
  always)
- wasm-uu CI-equivalent build clean: cargo build --target
  wasm32-unknown-unknown -p manifold-csg --no-default-features
  --features unstable-wasm-uu --tests --examples
- Produced wasm has zero unexpected imports (`wasm-objdump -x -j Import`
  reports "Section not found") — confirms ray_cast now resolves against
  the helper-built manifold archive
- 12 playground Node tests pass against the new build
- cargo fmt + cargo clippy clean

Followup: when shim's non-alpha v0.4.0 ships (after #1690 merges), bump
the pin off `-alpha.1`. No code changes expected — just a tag swap.

Author: zmerlynn

.claude/skills/deep-review/SKILL.md

@@ -195,7 +195,7 @@ This crate tracks manifold3d upstream. Verify:
 - Pinned version in `build.rs` — what version are we on? What's latest? What changed?
 - ABI compatibility — have any C API function signatures changed in newer manifold3d releases?
 - Deprecated functions — are we binding any C API functions that upstream has deprecated?
-- **wasm32-unknown-unknown cfg-gates may need revisiting.** Grep for `target_os = "unknown"` across the workspace. Each gated FFI declaration / safe wrapper / test is gated because that C API surface postdates the shim's tested manifold pin. When the shim's tested pin moves to (or past) our host pin, those gates can be removed. Currently gated: `manifold_ray_*` (ray casting). The OBJ I/O gates are gated for a different reason (iostream patches strip them) and stay regardless.
+- **wasm32-unknown-unknown cfg-gates may need revisiting.** Grep for `target_os = "unknown"` across the workspace. Each gated FFI declaration / safe wrapper / test is gated because that C API surface postdates the shim's tested manifold pin. When the shim's tested pin moves to (or past) our host pin, those gates can be removed. The OBJ I/O gates (`manifold_*_obj`) are gated for a different reason (iostream patches strip them) and stay regardless.
 - New capabilities — has upstream added significant new C API surface (new types, new operations) that we're missing?
 - Build system changes — has manifold3d changed its CMake structure, added/removed FetchContent deps, changed library names?
 - Known upstream bugs — check manifold3d issues for bugs affecting functions we bind (especially boolean operations, MeshGL64, CrossSection offset)

.claude/skills/update-upstream/SKILL.md

@@ -34,6 +34,7 @@ git checkout -b update-upstream-<ref>
 - Otherwise, query upstream master HEAD: `gh api repos/elalish/manifold/git/refs/heads/master --jq '.object.sha'`
 - Show the user: current pin (from `MANIFOLD_VERSION` in `crates/manifold-csg-sys/build.rs`), the target, and a one-line commit summary of what's between them: `gh api repos/elalish/manifold/compare/<current>...<target> --jq '{ahead_by: .ahead_by, commits: [.commits[] | {sha: .sha[0:8], message: (.commit.message | split("\n")[0])}]}'`
 - Confirm before proceeding.
+- **Check shim coverage.** Before committing to the target, verify `wasm-cxx-shim` supports it. Look at the latest shim release's `MANIFOLD_GIT_TAG` default (in the helper at `cmake/WasmCxxShimManifold.cmake`, or in the release notes). If the target SHA is past the shim's tested pin, flag it: either pick a target the shim already supports, or be ready to cfg-gate any new C API on `not(all(target_arch = "wasm32", target_os = "unknown"))` (the wasm-uu lane will fall back to the shim's tested pin via `wasm_cxx_shim_add_manifold()`'s default). Mismatch without gating produces wasm-uu link failures — see CLAUDE.md "Versioning" section.
 
 ### 3. Update the pin
 

CLAUDE.md

@@ -21,6 +21,7 @@ The sys crate clones manifold3d (pinned to a specific commit on master, post-v3.
 - **`manifold-csg-sys`** uses version `{major}.{minor}.{patch}` where major.minor tracks the upstream manifold3d version and patch >= 100 is our release number. For example, `3.4.100` tracks manifold3d v3.4.1, and `3.4.101` would be our next release against the same upstream. Patch bumps (e.g., `3.4.101` → `3.4.102`) must be semver-compatible: no removed or changed function signatures, only additions.
 - **`manifold-csg`** uses standard semver (`0.1.0`, etc.) independent of the upstream version. Its `Cargo.toml` pins the sys crate version it depends on.
 - When bumping the manifold3d pin in `build.rs`, the sys crate version must be updated to match (e.g., manifold3d v3.5.0 -> sys crate `3.5.100`).
+- **Before bumping `MANIFOLD_VERSION`, check that `wasm-cxx-shim` supports the new pin.** The shim's helper (`wasm_cxx_shim_add_manifold()`) ships carry-patches generated against a specific manifold commit; pins past that point may not patch cleanly, and FFI declarations for any C API added in the gap will produce wasm-uu link failures. Two paths if the shim hasn't caught up: (1) wait for a shim release that pins past your target SHA, or (2) cfg-gate the new FFI surface on `not(all(target_arch = "wasm32", target_os = "unknown"))` so the wasm-uu lane stays on the shim's tested pin. The "Pin / shim follow-ups" section below covers the post-bump cleanups for path (2).
 - The sys crate pins upstream to a specific commit SHA rather than a tag. This is necessary because upstream doesn't follow strict semver — minor releases can include breaking changes. Pinning to a commit gives us the same reproducibility as a tag, while allowing us to pick up post-release fixes and carry-patches between releases.
 - **Version bumps**: feature PRs may (and usually should) include their own version bump so the merge is ready to publish. The `/publish` skill will bump at publish time only if no PR has done so since the last release. Note that `cargo-semver-checks` CI requires a bump whenever the PR changes the public API in a way the current version doesn't allow (e.g., a breaking change requires a minor bump pre-1.0).
 - **Facade crates** (`manifold3d`, `manifold3d-sys`) always ship in lockstep with their canonical counterparts (`manifold-csg`, `manifold-csg-sys`) via `=` version pins. Bumping the canonical means bumping the facade.
@@ -48,7 +49,7 @@ The sys crate clones manifold3d (pinned to a specific commit on master, post-v3.
 
 Things to revisit whenever the manifold pin moves OR `wasm-cxx-shim` cuts a new release:
 
-- **Re-evaluate wasm32-unknown-unknown cfg-gates.** Any FFI declaration / safe wrapper / test gated on `not(all(target_arch = "wasm32", target_os = "unknown"))` exists because that surface postdates the shim's tested manifold pin. When the shim's tested pin moves up to (or past) our host pin, those gates can be dropped and the surface unified across targets. Current gated surface: `manifold_ray_*` (ray casting), `manifold_*_obj` (OBJ I/O — gated for a different reason: iostream patches strip it). Grep for `target_os = "unknown"` to enumerate.
+- **Re-evaluate wasm32-unknown-unknown cfg-gates.** Any FFI declaration / safe wrapper / test gated on `not(all(target_arch = "wasm32", target_os = "unknown"))` exists because that surface postdates the shim's tested manifold pin. When the shim's tested pin moves up to (or past) our host pin, those gates can be dropped and the surface unified across targets. Current gated surface: `manifold_*_obj` (OBJ I/O — gated for a different reason: iostream patches strip it; this stays regardless). Ray casting is **no longer gated** as of shim v0.4.0-alpha.1, whose tested pin matches our host pin. Grep for `target_os = "unknown"` to enumerate.
 - **Re-evaluate carry-patches.** For each patch in `crates/manifold-csg-sys/patches/` (if any), check whether it's merged upstream and included in the new pin; if so, delete it.
 
 ## Carry-patches

Cargo.toml

@@ -10,7 +10,7 @@ members = [
 resolver = "2"
 
 [workspace.package]
-version = "0.1.7"
+version = "0.1.8"
 edition = "2024"
 license = "Apache-2.0 OR MIT"
 repository = "https://github.com/zmerlynn/manifold-csg"

crates/manifold-csg-sys/Cargo.toml

@@ -1,7 +1,7 @@
 [package]
 name = "manifold-csg-sys"
 description = "Raw FFI bindings to the manifold3d C API for constructive solid geometry"
-version = "3.4.106"
+version = "3.4.107"
 edition.workspace = true
 license.workspace = true
 repository.workspace = true

crates/manifold-csg-sys/build.rs

@@ -404,7 +404,11 @@ fn main() {
 // build.rs instead of a cmake file).
 
 const WASM_CXX_SHIM_GIT: &str = "https://github.com/zmerlynn/wasm-cxx-shim.git";
-const WASM_CXX_SHIM_TAG: &str = "v0.3.0";
+// v0.4.0-alpha.1 pins manifold to the same commit as our host build
+// (`5f95a3ac`), so the wasm-uu lane sees the same C API surface (including
+// ray_cast). Will move to non-alpha v0.4.0 once upstream manifold#1690
+// (the iostream gating PR the alpha vendors as a carry-patch) merges.
+const WASM_CXX_SHIM_TAG: &str = "v0.4.0-alpha.1+5f95a3ac";
 
 fn build_wasm_unknown_unknown() {
     println!("cargo:rerun-if-changed=build.rs");

crates/manifold-csg-sys/src/lib.rs

@@ -49,10 +49,6 @@ pub struct ManifoldSimplePolygon {
 }
 
 /// Opaque handle to a manifold3d `RayHitVec` (vector of ray hit results).
-///
-/// Unavailable on `wasm32-unknown-unknown` — that lane builds against the
-/// shim's tested manifold pin (v3.4.1), which predates ray casting.
-#[cfg(not(all(target_arch = "wasm32", target_os = "unknown")))]
 #[repr(C)]
 #[derive(Debug)]
 pub struct ManifoldRayHitVec {
@@ -163,10 +159,6 @@ pub struct ManifoldProperties {
 }
 
 /// Result of a ray-manifold intersection test.
-///
-/// Unavailable on `wasm32-unknown-unknown` — see [`ManifoldRayHitVec`] for
-/// the rationale.
-#[cfg(not(all(target_arch = "wasm32", target_os = "unknown")))]
 #[repr(C)]
 #[derive(Debug, Clone, Copy)]
 pub struct ManifoldRayHit {
@@ -276,7 +268,6 @@ unsafe extern "C" {
     pub fn manifold_box_size() -> usize;
     pub fn manifold_rect_size() -> usize;
     pub fn manifold_triangulation_size() -> usize;
-    #[cfg(not(all(target_arch = "wasm32", target_os = "unknown")))]
     pub fn manifold_ray_hit_vec_size() -> usize;
 
     // ── Allocation ─────────────────────────────────────────────────────
@@ -292,7 +283,6 @@ unsafe extern "C" {
     pub fn manifold_alloc_box() -> *mut ManifoldBox;
     pub fn manifold_alloc_rect() -> *mut ManifoldRect;
     pub fn manifold_alloc_triangulation() -> *mut ManifoldTriangulation;
-    #[cfg(not(all(target_arch = "wasm32", target_os = "unknown")))]
     pub fn manifold_alloc_ray_hit_vec() -> *mut ManifoldRayHitVec;
 
     // ── Destruction (destruct only, does not free) ─────────────────────
@@ -308,7 +298,6 @@ unsafe extern "C" {
     pub fn manifold_destruct_box(b: *mut ManifoldBox);
     pub fn manifold_destruct_rect(b: *mut ManifoldRect);
     pub fn manifold_destruct_triangulation(m: *mut ManifoldTriangulation);
-    #[cfg(not(all(target_arch = "wasm32", target_os = "unknown")))]
     pub fn manifold_destruct_ray_hit_vec(v: *mut ManifoldRayHitVec);
 
     // ── Deletion (destruct + free) ─────────────────────────────────────
@@ -324,7 +313,6 @@ unsafe extern "C" {
     pub fn manifold_delete_box(b: *mut ManifoldBox);
     pub fn manifold_delete_rect(b: *mut ManifoldRect);
     pub fn manifold_delete_triangulation(m: *mut ManifoldTriangulation);
-    #[cfg(not(all(target_arch = "wasm32", target_os = "unknown")))]
     pub fn manifold_delete_ray_hit_vec(v: *mut ManifoldRayHitVec);
 
     // ── Polygons ───────────────────────────────────────────────────────
@@ -1072,12 +1060,8 @@ unsafe extern "C" {
     ) -> *mut ManifoldManifold;
 
     // ── Ray casting ─────────────────────────────────────────────────────
-    //
-    // Postdates the manifold v3.4.1 pin the wasm32-uu lane builds against,
-    // so the whole ray-cast surface is cfg-elided on that target.
 
     /// Cast a ray from `origin` to `end` against a manifold, returning all hits.
-    #[cfg(not(all(target_arch = "wasm32", target_os = "unknown")))]
     pub fn manifold_ray_cast(
         mem: *mut ManifoldRayHitVec,
         m: *const ManifoldManifold,
@@ -1090,11 +1074,9 @@ unsafe extern "C" {
     ) -> *mut ManifoldRayHitVec;
 
     /// Number of hits in a ray hit vector.
-    #[cfg(not(all(target_arch = "wasm32", target_os = "unknown")))]
     pub fn manifold_ray_hit_vec_length(v: *const ManifoldRayHitVec) -> usize;
 
     /// Get a hit by index from a ray hit vector.
-    #[cfg(not(all(target_arch = "wasm32", target_os = "unknown")))]
     pub fn manifold_ray_hit_vec_get(v: *const ManifoldRayHitVec, idx: usize) -> ManifoldRayHit;
 
     // ── Bounding box ────────────────────────────────────────────────────

crates/manifold-csg-sys/wasm32-uu/CMakeLists.txt

@@ -66,11 +66,12 @@ add_compile_options(
 )
 
 # FetchContent + patches + manifold/Clipper2 options + base compile flags.
-# Uses the helper's tested-pin defaults (manifold v3.4.1, Clipper2 matching
-# SHA). The host build pins newer SHAs to pick up post-3.4.1 fixes; FFI
-# declarations and safe wrappers for any C API surface that postdates v3.4.1
-# (e.g., manifold_ray_cast) are cfg-gated off on this target so the wasm
-# produced here has no unresolved imports against the helper's pin.
+# Uses the helper's tested-pin default. As of shim v0.4.0-alpha.1 the
+# helper's default pin matches our host pin (`5f95a3ac`), so the wasm-uu
+# lane sees the same C API surface as the host build (including ray_cast).
+# When the host pin moves past the helper's tested pin again, either
+# override via `MANIFOLD_GIT_TAG` here or cfg-gate the new surface on
+# this target — see the "Pin / shim follow-ups" section in CLAUDE.md.
 wasm_cxx_shim_add_manifold()
 
 # Force the manifold + Clipper2 archives to build by default. Without

crates/manifold-csg/Cargo.toml

@@ -19,7 +19,7 @@ nalgebra = ["dep:nalgebra"]
 unstable-wasm-uu = ["manifold-csg-sys/unstable-wasm-uu"]
 
 [dependencies]
-manifold-csg-sys = { path = "../manifold-csg-sys", version = "3.4.106", default-features = false }
+manifold-csg-sys = { path = "../manifold-csg-sys", version = "3.4.107", default-features = false }
 thiserror = "2"
 log = "0.4"
 nalgebra = { version = "0.34", optional = true }

crates/manifold-csg/src/lib.rs

@@ -23,7 +23,6 @@ pub mod bounding_box;
 pub mod cross_section;
 pub mod manifold;
 pub mod mesh;
-#[cfg(not(all(target_arch = "wasm32", target_os = "unknown")))]
 pub mod ray;
 pub mod rect;
 pub mod triangulation;
@@ -38,7 +37,6 @@ pub use manifold::{
 };
 pub use manifold_csg_sys::ManifoldOpType as OpType;
 pub use mesh::{MeshGL, MeshGL64};
-#[cfg(not(all(target_arch = "wasm32", target_os = "unknown")))]
 pub use ray::RayHit;
 pub use rect::Rect;
 pub use triangulation::triangulate_polygons;