==============================================================================
INPUT: nullpmc.lua

3: function instance:Constructor()
4: .   function self:Bar()
5: .   end;
6: .   function self:Bar()
7: .   end;
8: end;
9:
10: instance:Constructor()

==============================================================================
ERROR: installable_luap nullpmc.lua

$ ./installable_luap nullpmc.lua
luap: nullpmc.lua:6: Null PMC access in set_pmc_keyed()
stack traceback:
    nullpmc.lua:6: in function 'instance.Constructor_13'
    nullpmc.lua:10: in main chunk
    [PIR]: in function 'docall'
    [PIR]: in function '&start'
    [PIR]: in function 'eval'
    [PIR]: in function 'evalfiles'
    [PIR]: in function 'command_line'
    [PIR]: in function 'main'

==============================================================================
OUTPUT: installable_luap --target=pir nullpmc.lua


.namespace []
.sub "instance.Constructor_13" :anon :lex :subid("post29") :outer("post33")
    .param pmc param_self_1 :optional
    .param int has_param_self_1 :opt_flag
    .param pmc extra :slurpy
.annotate 'file', "nullpmc.lua"
.annotate 'line', 3
    .local pmc k_Bar
    box k_Bar, "Bar"
    .local pmc subr
    subr = interpinfo .INTERPINFO_CURRENT_SUB

    .lex "self_1", param_self_1
    if has_param_self_1, vivify_14
    new param_self_1, "LuaNil"
  vivify_14:
.annotate 'line', 4
    .const "Sub" fct_17 = "post18"
    newclosure $P19, fct_17
    $P20 = subr."getfenv"()
    $P19."setfenv"($P20)
    set param_self_1[k_Bar], $P19
.annotate 'line', 6
    .const "Sub" fct_23 = "post24"
    newclosure $P25, fct_23
    $P26 = subr."getfenv"()
    $P25."setfenv"($P26)
    find_lex $P27, "self_2"
    set $P27[k_Bar], $P25
.end