[M3devel] narrow still failing..

[mika at async.caltech.edu]

Did you try using my bdd.tgz ?

I am getting this error on: 

ancient PM3 on FreeBSD4

head CM3 on AMD64_LINUX

few months old CM3 on ARM_LINUX (Raspberry Pi)

I doubt you will get it on LINUXLIBC6 if you don't get it on the others.

I already tried rearranging the files (the implementation and interfaces
are split in a funny way across BDD.i3, BDDImpl.i3, BDD.m3, BDDImpl.m3
right now).  With no effect.  I don't know what it is about my code that's
tripping up the compiler.

It's also a "decent" BDD package so someone (me I guess, but anyone
else who's interested is welcome to) might want to add it to CM3... :-)
Kind of a pain if you can't print out the debugging info though!
(Actually the workarounds are OK.)

    Mika

"Rodney M. Bates" writes:
>
>
>On 01/20/2014 10:18 PM, mika at async.caltech.edu wrote:
>> Were you able to get it to fail on any of your computers?
>
>No, the only times I got narrow failures were due to errors
>in my trial cases.
>
>I have only tried AMD64_LINUX, but should be able to get this onto a
>LINUXLIBC6 system.
>
>>
>> Your Z fails for me---CM3 and PM3 both.
>>
>> (579)truffles:~/bsd/refany/src>../AMD64_LINUX/refany
>>
>>
>> ***
>> *** runtime error:
>> ***    An explicit or implicit NARROW() operation failed.
>> ***    file "../src/Main.m3", line 30
>> ***
>
>Well that torpedos both my theories.
>
>But it is hard to imagine that bad code generated for an implicit narrow
>on an assignment could ever have gone unnoticed so long.  I thought it
>might be more believable if it only happened when narrowing an actual
>parameter before passing it.
>
>>
>> Abort
>> (580)truffles:~/bsd/refany/src>cat Mai
>> Main.m3~  Main.m3
>> (580)truffles:~/bsd/refany/src>cat -n Main.m3
>>       1  MODULE Main;
>>       2  IMPORT BDD, IO;
>>       3
>>       4  PROCEDURE P() : REFANY =
>>       5    BEGIN
>>       6      VAR x : REFANY;
>>       7      BEGIN
>>       8        x := BDD.New("a");
>>       9        Z(x);
>>      10        RETURN x
>>      11      END
>>      12    END P;
>>      13
>>      14  PROCEDURE Q() =
>>      15    BEGIN
>>      16      IO.Put(P() & "\n")
>>      17    END Q;
>>      18
>>      19  (*
>>      20  PROCEDURE Z(VAR x : REFANY) =
>>      21    BEGIN
>>      22      TYPECASE x OF
>>      23        BDD.T(b) => x := BDD.Format(b)
>>      24      END;
>>      25    END Z;
>>      26  *)
>>      27  PROCEDURE Z(VAR x : REFANY) =
>>      28     VAR b: BDD.T;
>>      29     BEGIN
>>      30       b := x;
>>      31       x := BDD.Format(b)
>>      32     END Z;
>>      33
>>      34
>>      35
>>      36  BEGIN
>>      37    Q()
>>      38  END Main.
>> (581)truffles:~/bsd/refany/src>
>> "Rodney M. Bates" writes:
>>> What does this do?
>>>
>>> PROCEDURE Z(VAR x : REFANY) =
>>>    VAR b: BDD.T;
>>>    BEGIN
>>>      b := x;
>>>      x := BDD.Format(b)
>>>    END Z;
>>>
>>> The common property of the failing cases seems to be the necessity
>>> of a runtime narrow check when passing x to BDD.Format.
>>>
>>> So far, I haven't been able to reproduce the failure on AMD64_LINUX,
>>> with even more irrelevant (one would think) stuff pared out.  I moved
>>> T, Root, and Format into main, removed all but one fields of T and Root,
>>> replaced BDD.New by NEW(Root) and removed Symtab and most of the body
>>>from Format.
>>>
>>> Looking at your code, I agree it should work.
>>>
>>>
>>> On 01/19/2014 04:01 PM, mika at async.caltech.edu wrote:
>>>> As in the ISTYPE/TYPECASE example, the following works:
>>>>
>>>>
>>>> PROCEDURE Z(VAR x : REFANY) =
>>>>     BEGIN
>>>>       TYPECASE x OF
>>>>         BDD.T(b) => x := BDD.Format(b)
>>>>       END;
>>>>     END Z;
>>>>
>>>> (244)rover:~/refany/src>../FreeBSD4/refany
>>>> a
>>>>
>>>>
>>>> This does NOT work:
>>>>
>>>> PROCEDURE Z(VAR x : REFANY) =
>>>>     BEGIN
>>>>       TYPECASE x OF
>>>>         BDD.T(b) => x := BDD.Format(x)
>>>>       END;
>>>>     END Z;
>>>>
>>>>
>>>> (242)rover:~/refany/src>../FreeBSD4/refany
>>>>
>>>>
>>>> ***
>>>> *** runtime error:
>>>> ***    NARROW failed
>>>> ***    file "/big/home/mika/refany/src/Main.m3", line 22
>>>> ***
>>>>
>>>>     use option @M3stackdump to get a stack trace
>>>> Abort
>>>>
>>>>
>>>> Same result PM3 / CM3.
>>>>
>>>>        Mika
>>>>
>>