Motivation

Julia cannot inline functions containing try-finally. This blocks the compiler from optimizing @inline @with_pool functions in hot loops.

Removing try-finally yields ~15-25% speedup on typical patterns (single/nested/multi-type), with larger gains on Julia 1.10 LTS. LLVM IR confirms the exception handler frame is completely eliminated.

What Changed

@with_pool now uses direct rewind insertion instead of try-finally:

• rewind! inserted at every exit point: implicit return, explicit return, break, continue
• Entry depth guard (while pool._current_depth > _entry_depth + 1) for deferred recovery when inner scope throws and outer catches
• @goto safety: compile-time hard error on external jumps (set-difference analysis of goto targets vs local labels)

The old try-finally behavior is preserved as @safe_with_pool / @safe_maybe_with_pool.

API

Exception Contract