- Each build's folder holds optional symbol files with full line tables: a zipped dSYM per Mac, and a zipped DWARF .debug file per Linux and Windows executable, which the executable finds by its debug link

Release builds compile with line tables and move them out of each executable,
so the shipped binaries stay their size and the updater never downloads the
symbol files. Linux executables gain a build id. Windows gets DWARF rather than
a PDB, since lld builds a PDB's functions and lines from CodeView alone and
rustc emits CodeView only for MSVC targets.

Assisted-by: claude-opus-5.5