perl -le 'use blib; use Alter qw(ego); ego($a, { 1, 2 })->{"foo"} = "bar"'
current: 166 # OP_METHOD
next: 134    # OP_EXISTS
scalar context
Segmentation fault

perl -le 'use blib; use Alter qw(ego); @{ ego( $a, { 1, 2 }) } = (1,2,3)'
current: 166 # OP_METHOD
next: 178    # OP_ENTER    hmm?
scalar context
Segmentation fault

perl -le 'use blib; use Alter qw(ego); ego( $a, { 1, 2 })->[0] = (1,2,3)'
current: 166 # OP_METHOD
next: 125    # OP_QUOTEMETA  interesting...
scalar context
Segmentation fault