bug: WASM engine segfaults after repeated builds in same process

[carlos-alm]

Found during dogfooding v3.1.2

Severity: Low
Command: node scripts/benchmark.js

Reproduction

node scripts/benchmark.js
# Run sequence: WASM full build → 3x no-op → 1-file rebuild #1 → #2 → SEGFAULT on #3

Expected behavior

WASM engine should survive repeated incremental builds in the same process without crashing.

Actual behavior

After 6+ WASM builds in the same Node.js process (1 full + 3 no-op + 2 one-file), the 3rd one-file rebuild segfaults (exit code 139). The incremental benchmark script (incremental-benchmark.js) runs the same pattern but survives — suggesting memory pressure or accumulated state in tree-sitter WASM is the trigger.

Root cause

Likely tree-sitter WASM memory accumulation across repeated parser invocations in the same process. The build benchmark runs more operations before reaching the 1-file phase (full build + queries + no-op) compared to the incremental benchmark, which may push WASM memory past the threshold.

Environment

• Platform: Windows 11 Pro, win32-x64, Node v22.18.0
• tree-sitter-wasms: as of v3.1.2

Suggested fix

• Investigate if tree-sitter WASM parsers are properly disposed between builds
• Consider calling parser.delete() on WASM parsers after each build cycle
• Or run WASM benchmarks in a child process to isolate memory