Use MACH_PORT_VALID() when wanting to check if a mach port is valid, instead of checking for MACH_PORT_NULL. MACH_PORT_VALID() is the correct way to check for validity since it also checks for the MACH_PORT_DEAD value.
Created attachment 424783 [details] Patch
Committed r275327: <https://commits.webkit.org/r275327> All reviewed patches have been landed. Closing bug and clearing flags on attachment 424783 [details].
<rdar://problem/76080057>