C:\test>perl -MO=Terse
sub somefunction{ $_[0] + 1 }

$shared = somefunction( $shared );
^Z
LISTOP (0x191d7e0) leave [1]
    OP (0x191d7c4) enter
    COP (0x191d804) nextstate
    ## install exception handler here
    BINOP (0x191d840) sassign
    ## Exception handler catches here <<<<---------------------------^
    ## Critical section entered here at second attempt
        UNOP (0x191d864) entersub [4]
            UNOP (0x191d8a0) null [141]
                OP (0x191d884) pushmark
                UNOP (0x191d8c4) null [15]
                    PADOP (0x191d8e4) gvsv  GV (0x22507c) *shared
                    ## Exception raised here---------------------------^
                UNOP (0x191d904) null [17]
                    PADOP (0x191d924) gv  GV (0x225088) *somefunction
        UNOP (0x191d944) null [15]
            PADOP (0x191d964) gvsv  GV (0x22507c) *shared
    ## ExitCriticalSection here.
- syntax OK