fn guard_block(panicked: &AtomicBool, input: &str, body: impl FnOnce())Expand description
Run one audio-callback block with its panic caught.
cpal calls this body from its own frame, so an unwind out of it crosses
the FFI boundary and aborts the process as rust_foreign_exception - the
signature in #2426’s report. This is the one guard that can stop that
crossing; after it the capture delivers nothing more, and the log names the
loss once, with the input and the backtrace taken at the raise.