fix: zero-initialize WASM page buffers to prevent memory corruption#142
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sauyon wants to merge 1 commit intocoder:mainfrom
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fix: zero-initialize WASM page buffers to prevent memory corruption#142sauyon wants to merge 1 commit intocoder:mainfrom
sauyon wants to merge 1 commit intocoder:mainfrom
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…oder#141) PageList only zeroed page buffers in debug/safe builds, relying on the OS to guarantee zeroed memory in release builds. On WASM there is no OS guarantee — the allocator reuses freed memory as-is. This caused two bugs: 1. Stale cell data from freed terminals appearing in newly created ones 2. WASM memory corruption after freeing terminals that processed multi-codepoint grapheme clusters (flag emoji, skin tones, ZWJ sequences), crashing all subsequent terminal writes The fix makes @Memset(page_buf, 0) unconditional on WASM in both initPages and createPageExt. Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
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PageList only zeroed page buffers in debug/safe builds, relying on the OS to guarantee zeroed memory in release builds. On WASM there is no OS guarantee — the allocator reuses freed memory as-is. This caused two bugs:
The fix makes @Memset(page_buf, 0) unconditional on WASM in both initPages and createPageExt.
Includes two previously-failing regression tests. Should resolve #141.