6558595ca3
When merging `.bss` into a code section (e.g., `/MERGE:.bss=.text`), the INT3 gap-filling loop in `writeSections()` would write past the output buffer. This happens because `.bss` chunks have `hasData=false`, so they contribute to `VirtualSize` but not `SizeOfRawData`. The loop was using chunk RVAs without checking if they exceeded the raw data region. This caused a crash on Windows with `/FILEALIGN:1` (access violation 0xC0000005). The tight alignment leaves no slack in the mapped buffer, so the overflow immediately hits unmapped memory. The fix bounds all memset operations to `rawSize` and exits early when encountering chunks beyond the raw data boundary. Fixes #180406
See docs/NewLLD.rst