Plain "./fio" segfaults on FreeBSD

Plain "./fio" segfaults on FreeBSD

[Bruce Cran]

The latest code from git (built using clang) causes a segfault after 
printing the usage text when "./fio" is run:

[New LWP 100111]
No jobs(s) defined

fio-2.2.5-28-g93eeb
[usage text]
[New Thread 801c06400 (LWP 100111/fio)]

Program received signal SIGSEGV, Segmentation fault.
[Switching to Thread 801c06400 (LWP 100111/fio)]
flist_empty (head=0x802000040) at flist.h:119
119             return head->next == head;
Current language:  auto; currently minimal
(gdb) p head
$1 = (const struct flist_head *) 0x802000040

Also, could we update -std=gnu99 to -std=c11 and use _Static_assert in 
compiler.h? Currently, turning optimizations off in the Makefile causes 
linker failures such as "fio/libfio.c:308: undefined reference to 
`__compiletime_assert_308'".

-- 
Bruce

Re: Plain "./fio" segfaults on FreeBSD

[Jens Axboe]

On 02/25/2015 03:50 PM, Bruce Cran wrote:
> The latest code from git (built using clang) causes a segfault after
> printing the usage text when "./fio" is run:
> 
> [New LWP 100111]
> No jobs(s) defined
> 
> fio-2.2.5-28-g93eeb
> [usage text]
> [New Thread 801c06400 (LWP 100111/fio)]
> 
> Program received signal SIGSEGV, Segmentation fault.
> [Switching to Thread 801c06400 (LWP 100111/fio)]
> flist_empty (head=0x802000040) at flist.h:119
> 119             return head->next == head;
> Current language:  auto; currently minimal
> (gdb) p head
> $1 = (const struct flist_head *) 0x802000040

I can reproduce this, very strange... I'll debug it.

> Also, could we update -std=gnu99 to -std=c11 and use _Static_assert in
> compiler.h? Currently, turning optimizations off in the Makefile causes
> linker failures such as "fio/libfio.c:308: undefined reference to
> `__compiletime_assert_308'".

I think it'd be more bullet proof (considering other platforms) to just
not do the compile time asserts at all if optimizations aren't enabled.
I'd be happy to take a patch for that...

-- 
Jens Axboe

Re: Plain "./fio" segfaults on FreeBSD

[Jens Axboe]

On 02/26/2015 03:32 PM, Jens Axboe wrote:
> On 02/25/2015 03:50 PM, Bruce Cran wrote:
>> The latest code from git (built using clang) causes a segfault after
>> printing the usage text when "./fio" is run:
>>
>> [New LWP 100111]
>> No jobs(s) defined
>>
>> fio-2.2.5-28-g93eeb
>> [usage text]
>> [New Thread 801c06400 (LWP 100111/fio)]
>>
>> Program received signal SIGSEGV, Segmentation fault.
>> [Switching to Thread 801c06400 (LWP 100111/fio)]
>> flist_empty (head=0x802000040) at flist.h:119
>> 119             return head->next == head;
>> Current language:  auto; currently minimal
>> (gdb) p head
>> $1 = (const struct flist_head *) 0x802000040
> 
> I can reproduce this, very strange... I'll debug it.

This should fix it:

http://git.kernel.dk/?p=fio.git;a=commit;h=3d0e3417997d9caa27cf97462e15ba437d285d29

-- 
Jens Axboe