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## Summary
- Fix two off-by-one bounds check errors that used `>` instead of `>=`
- Both bugs could cause undefined behavior (array out-of-bounds access)
when an index equals the array length
## The Bugs
### 1. `src/install/postinstall_optimizer.zig:62`
```zig
// Before (buggy):
if (resolution > metas.len) continue;
const meta: *const Meta = &metas[resolution]; // Out-of-bounds when resolution == metas.len
// After (fixed):
if (resolution >= metas.len) continue;
```
### 2. `src/bundler/linker_context/doStep5.zig:10`
```zig
// Before (buggy):
if (id > c.graph.meta.len) return;
const resolved_exports = &c.graph.meta.items(.resolved_exports)[id]; // Out-of-bounds when id == c.graph.meta.len
// After (fixed):
if (id >= c.graph.meta.len) return;
```
## Why These Are Bugs
Valid array indices are `0` to `len - 1`. When `index == len`:
- `index > len` evaluates to `false` → check passes
- `array[index]` accesses `array[len]` → out-of-bounds / undefined
behavior
## Codebase Patterns
The rest of the codebase correctly uses `>=` for these checks:
- `lockfile.zig:484`: `if (old_resolution >= old.packages.len)
continue;`
- `lockfile.zig:522`: `if (old_resolution >= old.packages.len)
continue;`
- `LinkerContext.zig:389`: `if (source_index >= import_records_list.len)
continue;`
- `LinkerContext.zig:1667`: `if (source_index >= c.graph.ast.len) {`
## Test plan
- [x] Verified fix aligns with existing codebase patterns
- [ ] CI passes
🤖 Generated with [Claude Code](https://claude.com/claude-code)
Co-authored-by: Claude <noreply@anthropic.com>