Hi Yang

Very strange/fragile situation.
And sounds like I hit some gcc-ICEs during reduction.
May be 'instable/sporadic' ICEs (hmmm... what its may be?) interfere with
reduction process?
I'll try investigate further.

I have 4 variants after reduction:
--  from crashed version -- 32 lines/795 bytes
-- yesterday not crashed -- 42 lines/1263 bytes
-- one from today run -- 13 lines / 328 bytes
-- second from today -- 11 lines / 293 bytes

1) Run-time vary in range 350--850 secs
2) '--sllooww' key has no effect
3) today's reduction produces 5 times one output and 2 times the different
one
4) yesterday's reduction twice produces the same results

-- 32.ii : best from crashed creduce
-- 42.ii : from yesterday
-- 13.ii : one from today
-- 11.ii : second from today

42.ii and 13.ii and 11.ii was produced by the same
creduce-git-master-top-of-tree (as yesterday evening) +
llvm-3.5.0-precompiled-from-llvm.org

Fedora 21 / x86_64 was updated today morinng.


How to reproduce

1) build gcc-trunk rev.220090
(my cmd is:
~/src/gcc_current/configure --prefix=/usr/local/gcc_current --enable-static
--enable-checking=yes,df,fold,rtl --enable-languages=c,c++,lto
--enable-plugin --disable-libstdcxx-dual-abi --disable-multilib && make
)
2) cp 42.ii t.ii
3) creduce ./c.sh t.ii

And one more strangeness:

if I change 'grep test' in script from
   egrep "internal compiler error|too many memory references for" res
to
   grep "too many memory references for" res

then there are many messages : shell-init: error retrieving current
directory: getcwd: cannot access parent directories: No such file or
directory
and reduction is more deep. Probably smth with catch gcc-ICE?

In past when I run tests with compilers errors and hit ICE then extended
grep-test can catch ICE.
And in past I can isolate ICE and reduce further without it.

Very interesting what is different now :)

Thank you,
Dmitry


2015-01-26 5:09 GMT+03:00 Yang Chen <[email protected]>:

>  Hi Dmitry
>
> Thanks for reporting this!
>
> I've seen similar behavior before. My guess is that we might suffer from
> the phase-ordering problem. If it doesn't require too much effort, can you
> send us the reduced test case in your second case and the script that
> orchestrated the reduction? I will check if C-Reduce miss some obvious
> reduction opportunities. You don't need to reproduce the crashing behavior.
> Thanks.
>
> - Yang
>
>
> On 01/25/2015 11:32 AM, Дмитрий Дьяченко wrote:
>
>      Hi,
>  sorry for noise.
>
>  I rebuild creduce from scratch and there are no crashes.
>  I use: Fedora 21/x86_x64, creduce-git-top-of-tree,
> clang-3.5.0-precompiled-from-llvm.org.
>
>  But I have strange additional result:
>  -- prev (crashed) version works 740 secs and reduce 17KLOC (400Kb) down
> to 32 lines (795 bytes)
>  -- new (without craches) works 840 secs and reduce downto 42 lines (1263
> bytes)
>
>  If you are interested I can try reproduce this. Currently I dont know
> exactly about crached version how it was compiled and from which sources.
>
>  Thank you, sorry once again for noise.
>
>  Dmitry
>
> 2015-01-25 21:39 GMT+03:00 Дмитрий Дьяченко <[email protected]>:
>
>>   Hi!
>>
>>  With creduce-git, clang 3.7.0 (trunk 227039) Fedora 21/x86_64
>>  I get 2 similar crashes
>>  /usr/local/creduce/libexec/clang_delta
>> --transformation=reduce-pointer-level --counter=4|5 ...
>>
>>  Thanks,
>>  Dmitry
>>
>
>
>

Attachment: 11.ii
Description: Binary data

Attachment: 12.ii
Description: Binary data

Attachment: 32.ii
Description: Binary data

Attachment: 42.ii
Description: Binary data

Attachment: c.sh
Description: Bourne shell script

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