[erlang-questions] Potential bug in OTP_17.0-rc1 when converting map to binary and back

[Kostis Sagonas]

On 02/01/2014 06:41 PM, Gustav Simonsson wrote:
> After the announcement of OTP_17.0-rc1 I compiled the source and started
> playing with maps and proper.
>
> After testing a bunch of stuff like maps:to_list(maps:from_list(List)) I
> replicated a classic proper example to verify
> binary_to_term(term_to_binary(T)).
 > .... <SNIP>
> 2>  proper:quickcheck(t:prop_maps2(), [{numtests, 10000}]).
> ............ <SNIP> ...............................................
> Shrinking .......Segmentation fault (core dumped)
> .... <SNIP>
> Please let me know if you need a core and/or more details.
> It should be easy to replicate given the above code though on various archs.


Indeed, this is very easy to replicate.  On my first attempt, I got 
equally unlucky as Simon and OTP seg faulted when PropEr attempted to 
shrink the offending test case. On my second attempt, I had better luck 
and shrinking worked:

Eshell V6.0  (abort with ^G)
1> proper:quickcheck(t:prop_maps2(), 10000).
...... <SNIP> .....
Failed: After 2090 test(s).
{[{{{},'mö\030?Ø',[],[[]],[]},{'\031¹DZ',75.25615709172015,9}},{{<<47,42,83,2:2>>},[{11.611456128457124,{[]},[],-7.568651682554733}]},{'þ\204HÅð¾óà',[[],[],[],-10,80,{},[]]},{{'Ñ\211l\030x\220Â\224é'},[-14.081931069838275,1,['\236Jñ',0],3,3.8086424574055755]},{{[],[{},[[{}]]],{},{}},{-7.668921456100702,-0.8537275447686942,0.2046413634772726,8.71091095449412,'X7¯³\237\030',{-11,{{}},-0.95809288292835,[{{}},'©uÆ']},-5.604771642421137}},{{[{},22.021800217282916],-2,7.289863377212738,'³]Ã\d',10.348710823806195},{{[[{},[5.428258856857506],[],'O\030:',-2]],22.20548610862955,102}}},{[1.730805378918121,'\201\226o\032',-5,-4,0.21576771814263207],<<145,249,4,86,26,4:3>>}]}

Shrinking ...................(19 time(s))
{[{{{},'mö\030?Ø',[],[[]],[]},{'\031¹DZ',75.25615709172015,9}},{{<<47,42,83,2:2>>},[{11.611456128457124,{[]},[],-7.568651682554733}]},{'\037\204HÅ>w6²',[[],[],[],-8,80,{},[]]},{{'Ñ\211l\030x\220Â\224é'},[-14.081931069838275,1,['z\003-',0],3,3.8086424574055755]},{'\v¹6\002',{-7.668921456100702,-0.8537275447686942,0.2046413634772726,8.71091095449412,'X7¯³\237\030',{-11,{{}},-0.95809288292835,[{{}},'©uÆ']},-5.604771642421137}},{{[{},22.021800217282916],-2,7.289863377212738,'³]Ã\d',10.348710823806195},{{[[{},[5.428258856857506],[],'O\030:',-2]],22.20548610862955,102}}},{[1.730805378918121,'\030\023%\020',-5,-4,0.21576771814263207],<<145,249,4,49,26,4:3>>}]}
false

false


PropEr can be obtained from: http://proper.softlab.ntua.gr/

Kostis