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The umbrella crate (arborium) had its own crates/arborium/src/wasm.rs providing C sysroot stubs (abort, malloc, strncpy, etc.) since the initial commit. When arborium-sysroot was created in PR bearcove#161, it provided corrected implementations of the same symbols, but the old copy was never removed. This caused two problems: 1. abort() was a no-op (fn abort() {}) instead of diverging (fn abort() -> !), meaning C code calling abort() on invariant violation would continue execution past a fatal error. 2. strncpy() did not zero-pad the remainder of the destination buffer after encountering a null byte, violating the C standard. The umbrella crate compiled both its own mod wasm and depended on arborium-sysroot, producing duplicate C symbol definitions on WASM targets. Fix: delete the old wasm.rs and remove the mod wasm declaration from the umbrella lib.rs template. arborium-sysroot (already a dependency) provides the correct implementations. Signed-off-by: Sebastien Tardif <sebtardif@ncf.ca>
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Problem
The umbrella crate (
arborium) has its owncrates/arborium/src/wasm.rsproviding C sysroot stubs (abort,malloc,strncpy, etc.) since the initial commit (^16cc98a, 2025-12-01). Whenarborium-sysrootwas created in #161, it provided corrected implementations of the same symbols, but the old copy was never removed.This causes two correctness issues:
abort()is a no-op (fn abort() {}) instead of diverging (fn abort() -> !). If tree-sitter's C code callsabort()on an invariant violation via the old sysroot, execution continues past a fatal error, risking memory corruption.strncpy()missing zero-padding. The old implementation breaks on the first null byte without zero-padding the remainder of the destination buffer, violating the C standard. Thearborium-sysrootversion correctly zero-pads.The umbrella crate compiled both its own
mod wasmand depended onarborium-sysroot, producing duplicate C symbol definitions on WASM targets.Fix
crates/arborium/src/wasm.rs(510 lines of stale code)mod wasm;from the umbrellalib.rstemplate (xtask/templates/umbrella_lib.stpl.rs)arborium-sysroot(already declared as a dependency incargo.stpl.toml) provides the correct implementations.Related
arborium-sysrootwith the corrected implementations but did not remove the old copy