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<?php $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);
Finding entry points
Branch analysis from position: 0
1 jumps found. (Code = 62) Position 1 = -2
filename:       /in/Tc9PW
function name:  (null)
number of ops:  19
compiled vars:  !0 = $undef, !1 = $undef2, !2 = $undef3, !3 = $unedf
line      #* E I O op                           fetch          ext  return  operands
-------------------------------------------------------------------------------------
    4     0  E >   ASSIGN                                                   !1, null
    5     1        ASSIGN                                                   !2, null
    6     2        UNSET_CV                                                 !2
    7     3        ECHO                                                     '%24undef+%3D%3D%3D+%24undef2%3F'
    8     4        INIT_FCALL                                               'var_dump'
          5        IS_IDENTICAL                                     ~6      !0, !1
          6        SEND_VAL                                                 ~6
          7        DO_ICALL                                                 
   10     8        ECHO                                                     '%24undef+%3D%3D%3D+%24undef3%3F'
   11     9        INIT_FCALL                                               'var_dump'
         10        IS_IDENTICAL                                     ~8      !3, !2
         11        SEND_VAL                                                 ~8
         12        DO_ICALL                                                 
   13    13        ECHO                                                     '%24undef2+%3D%3D%3D+%24undef3%3F'
   14    14        INIT_FCALL                                               'var_dump'
         15        IS_IDENTICAL                                     ~10     !1, !2
         16        SEND_VAL                                                 ~10
         17        DO_ICALL                                                 
         18      > RETURN                                                   1

Generated using Vulcan Logic Dumper, using php 8.0.0


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