Re: Libjava test failure Was: [PATCH] microblaze: microblaze.md: Use 'SI' instead of 'VOID' for operand 1 of 'call_value_intern'

[Andrew Haley <aph@redhat.com>]

On 10/06/2014 03:27 PM, Chen Gang wrote:
> On 10/6/14 21:54, Andrew Haley wrote:
>> On 10/06/2014 02:53 PM, Chen Gang wrote:
>>> On 10/6/14 16:37, Andrew Haley wrote:
>>>> On 06/10/14 05:08, Chen Gang wrote:
>>>>> After try normal configure, get almost the same result, I guess, our
>>>>> testsuite under Darwin x86_64 is OK.
>>>>>
>>>>> If no any additional reply within a week, I shall continue to try to
>>>>> analyze the libjava Throw_2 issue.
>>>>
>>>> Throw_2 is a test specially contrived to detect segfaults that are
>>>> not being correctly detected and turned into NullPointerException()s.
>>>> A failure indicates that the segfault signal handler is broken.
>>>
>>> OK, thank, at present, it passes compiling (can generate 'Throw_2.exe'),
>>> and after run it without any parameters, "1" is printed, but "2" is not
>>> printed.
>>>
>>> Under Fedora 20 x86_64, the same gcc code, it is OK ("2" can be printed),
>>> but under Darwin x86_64, it is "Abort trap: 6" instead of. The related
>>> code: "try{Double.parseDouble(str());}catch", and "str(){return null;}".
>>>
>>> And I shall continue to try to analyze it (within this month), and 
>>> welcome any additional ideas, suggestions, and completion for it, 
>>
>> Not every platform supports unwinding through signal handlers.  In x86
>> Linux there is some very clever code which interacts with the kernel to
>> allow this.
> 
> Excuse me, I am not quite familiar with Java, I guess what you said is:
> 
>  - The related feature need OS kernel support, if OS kernel does not
>    support, it may report "Abort trap: 6" or others.
> 
>  - And OS kernel has feature to support "1" printed does not mean it
>    also has feature to support "2" printed.
> 
>  - And I need try to make sure that my current Darwin kernel whether
>    supports it or not.
> 
> If what I guess is incorrect, please let me know, thanks.

That sounds approximately right, but it's changed a lot since I last
looked.  It may be that the magic is in glibc rather than the kernel.

> For me, whether Darwin kernel supports or not, we have to improve
> current implementation (may be testsuite configure or Makefile) to
> avoid testsuite breaking.

The testsuite isn't breaking: it's telling you something useful.

Andrew.