mirror of
https://github.com/apple/swift.git
synced 2025-12-21 12:14:44 +01:00
Mandatory copy propagation was primarily a stop-gap until lexcial lifetimes were implemented. It supposedly made variables lifetimes more consistent between -O and -Onone builds. Now that lexical lifetimes are enabled, it is no longer needed for that purpose (and will never satisfactorily meet that goal anyway). Mandatory copy propagation may be enabled again later as a -Onone " optimization. But that requires a more careful audit of the effect on debug information. For now, it should be disabled.
1.1 KiB
1.1 KiB