The test throws exceptions but did not link libc, so with
-fno-asynchronous-unwind-tables it failed to link (no __gxx_personality_v0)
on the supported WinLibs toolchain; the Windows CI job does not run on pull
requests. The valid case now maps 2 MiB at a 2-MiB boundary, so the mapping is
one resident run and both Reset calls take the exact-run path, and the test
requires that run.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
