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<?php error_reporting(0); $undef; $undef2 = null; $undef3 = null; unset($undef3); echo '$undef === $undef2?'; var_dump($undef === $undef2); echo '$undef === $undef3?'; var_dump($unedf === $undef3); echo '$undef2 === $undef3?'; var_dump($undef2 === $undef3); var_dump( get_defined_vars() );
Finding entry points
Branch analysis from position: 0
1 jumps found. (Code = 62) Position 1 = -2
filename:       /in/ohdqV
function name:  (null)
number of ops:  27
compiled vars:  !0 = $undef, !1 = $undef2, !2 = $undef3, !3 = $unedf
line      #* E I O op                           fetch          ext  return  operands
-------------------------------------------------------------------------------------
    2     0  E >   INIT_FCALL                                               'error_reporting'
          1        SEND_VAL                                                 0
          2        DO_ICALL                                                 
    4     3        ASSIGN                                                   !1, null
    5     4        ASSIGN                                                   !2, null
    6     5        UNSET_CV                                                 !2
    7     6        ECHO                                                     '%24undef+%3D%3D%3D+%24undef2%3F'
    8     7        INIT_FCALL                                               'var_dump'
          8        IS_IDENTICAL                                     ~7      !0, !1
          9        SEND_VAL                                                 ~7
         10        DO_ICALL                                                 
   10    11        ECHO                                                     '%24undef+%3D%3D%3D+%24undef3%3F'
   11    12        INIT_FCALL                                               'var_dump'
         13        IS_IDENTICAL                                     ~9      !3, !2
         14        SEND_VAL                                                 ~9
         15        DO_ICALL                                                 
   13    16        ECHO                                                     '%24undef2+%3D%3D%3D+%24undef3%3F'
   14    17        INIT_FCALL                                               'var_dump'
         18        IS_IDENTICAL                                     ~11     !1, !2
         19        SEND_VAL                                                 ~11
         20        DO_ICALL                                                 
   15    21        INIT_FCALL                                               'var_dump'
         22        INIT_FCALL                                               'get_defined_vars'
         23        DO_ICALL                                         $13     
         24        SEND_VAR                                                 $13
         25        DO_ICALL                                                 
         26      > RETURN                                                   1

Generated using Vulcan Logic Dumper, using php 8.0.0


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