[PATCH v2] libgcc: Use braces instead of macro's empty body to avoid xgcc warnings.

[PATCH v2] libgcc: Use braces instead of macro's empty body to avoid xgcc warnings.

[Chen Gang S]

The related warning (cross compile tile with --disable-threads):

  ../../../../gcc-tile-new/libgcc/libgcov-interface.c: In function '__gcov_fork':
  ../../../../gcc-tile-new/libgcc/libgcov-interface.c:182:53: warning: suggest braces around empty body in an 'if' statement [-Wempty-body]
       __GTHREAD_MUTEX_INIT_FUNCTION (&__gcov_flush_mx);
                                                       ^
2015-01-31  Chen Gang  <gang.chen.5i5j@gmail.com>

	* gthr-single.h (__GTHREAD_MUTEX_INIT_FUNCTION): Use braces
	instead of macro's empty body to avoid xgcc warnings.
---
 libgcc/gthr-single.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/libgcc/gthr-single.h b/libgcc/gthr-single.h
index f084fe2..01366f53 100644
--- a/libgcc/gthr-single.h
+++ b/libgcc/gthr-single.h
@@ -35,7 +35,7 @@ typedef int __gthread_recursive_mutex_t;
 
 #define __GTHREAD_ONCE_INIT 0
 #define __GTHREAD_MUTEX_INIT 0
-#define __GTHREAD_MUTEX_INIT_FUNCTION(mx)
+#define __GTHREAD_MUTEX_INIT_FUNCTION(mx) do {} while (0)
 #define __GTHREAD_RECURSIVE_MUTEX_INIT 0
 
 #define UNUSED __attribute__((unused))
-- 
1.9.3

Re: [PATCH v2] libgcc: Use braces instead of macro's empty body to avoid xgcc warnings.

[Andreas Schwab]

Chen Gang S <gang.chen@sunrus.com.cn> writes:

> 	* gthr-single.h (__GTHREAD_MUTEX_INIT_FUNCTION): Use braces
> 	instead of macro's empty body to avoid xgcc warnings.

It's actually an empty loop now.

Andreas.

-- 
Andreas Schwab, schwab@linux-m68k.org
GPG Key fingerprint = 58CA 54C7 6D53 942B 1756  01D3 44D5 214B 8276 4ED5
"And now for something completely different."

Re: [PATCH v2] libgcc: Use braces instead of macro's empty body to avoid xgcc warnings.

[Chen Gang S]

On 1/31/15 16:53, Andreas Schwab wrote:
> Chen Gang S <gang.chen@sunrus.com.cn> writes:
> 
>> 	* gthr-single.h (__GTHREAD_MUTEX_INIT_FUNCTION): Use braces
>> 	instead of macro's empty body to avoid xgcc warnings.
> 
> It's actually an empty loop now.
> 

Excuse me, I am not quite clear gcc version merging working flow. Now,
for gcc master branch (20150131), __GTHREAD_MUTEX_INIT_FUNCTION is still
as empty.

Could you provide more details about it?

Thanks.
-- 
Chen Gang

Open, share, and attitude like air, water, and life which God blessed

Re: [PATCH v2] libgcc: Use braces instead of macro's empty body to avoid xgcc warnings.

[Prathamesh Kulkarni]

On 31 January 2015 at 15:30, Chen Gang S <gang.chen@sunrus.com.cn> wrote:
> On 1/31/15 16:53, Andreas Schwab wrote:
>> Chen Gang S <gang.chen@sunrus.com.cn> writes:
>>
>>>      * gthr-single.h (__GTHREAD_MUTEX_INIT_FUNCTION): Use braces
>>>      instead of macro's empty body to avoid xgcc warnings.
The ChangeLog entry should be fixed to reflect it's an empty loop now.
something like:
* gthr-single.h (__GTHREAD_MUTEX_INIT_FUNCTION): Use empty do-while
loop as macro body to avoid xgcc warnings.

Thanks,
Prathamesh
>>
>> It's actually an empty loop now.
>>
>
> Excuse me, I am not quite clear gcc version merging working flow. Now,
> for gcc master branch (20150131), __GTHREAD_MUTEX_INIT_FUNCTION is still
> as empty.
>
> Could you provide more details about it?
>
> Thanks.
> --
> Chen Gang
>
> Open, share, and attitude like air, water, and life which God blessed

Re: [PATCH v2] libgcc: Use braces instead of macro's empty body to avoid xgcc warnings.

[Marek Polacek]

On Sat, Jan 31, 2015 at 05:13:53PM +0530, Prathamesh Kulkarni wrote:
> On 31 January 2015 at 15:30, Chen Gang S <gang.chen@sunrus.com.cn> wrote:
> > On 1/31/15 16:53, Andreas Schwab wrote:
> >> Chen Gang S <gang.chen@sunrus.com.cn> writes:
> >>
> >>>      * gthr-single.h (__GTHREAD_MUTEX_INIT_FUNCTION): Use braces
> >>>      instead of macro's empty body to avoid xgcc warnings.
> The ChangeLog entry should be fixed to reflect it's an empty loop now.
> something like:
> * gthr-single.h (__GTHREAD_MUTEX_INIT_FUNCTION): Use empty do-while
> loop as macro body to avoid xgcc warnings.

And since CL entries should describe what, not why, the "to avoid..."
part is redundant.

	Marek

Re: [PATCH v2] libgcc: Use braces instead of macro's empty body to avoid xgcc warnings.

[Chen Gang S]

On 1/31/15 19:49, Marek Polacek wrote:
> On Sat, Jan 31, 2015 at 05:13:53PM +0530, Prathamesh Kulkarni wrote:
>> On 31 January 2015 at 15:30, Chen Gang S <gang.chen@sunrus.com.cn> wrote:
>>> On 1/31/15 16:53, Andreas Schwab wrote:
>>>> Chen Gang S <gang.chen@sunrus.com.cn> writes:
>>>>
>>>>>      * gthr-single.h (__GTHREAD_MUTEX_INIT_FUNCTION): Use braces
>>>>>      instead of macro's empty body to avoid xgcc warnings.
>> The ChangeLog entry should be fixed to reflect it's an empty loop now.
>> something like:
>> * gthr-single.h (__GTHREAD_MUTEX_INIT_FUNCTION): Use empty do-while
>> loop as macro body to avoid xgcc warnings.
> 
> And since CL entries should describe what, not why, the "to avoid..."
> part is redundant.
> 

OK, thanks. I should send patch v3 within today.


Thanks.
-- 
Chen Gang

Open, share, and attitude like air, water, and life which God blessed

Re: [PATCH v2] libgcc: Use braces instead of macro's empty body to avoid xgcc warnings.

[Jeff Law]

On 01/30/2015 11:04 PM, Chen Gang S wrote:
> The related warning (cross compile tile with --disable-threads):
>
>    ../../../../gcc-tile-new/libgcc/libgcov-interface.c: In function '__gcov_fork':
>    ../../../../gcc-tile-new/libgcc/libgcov-interface.c:182:53: warning: suggest braces around empty body in an 'if' statement [-Wempty-body]
>         __GTHREAD_MUTEX_INIT_FUNCTION (&__gcov_flush_mx);
>                                                         ^
> 2015-01-31  Chen Gang  <gang.chen.5i5j@gmail.com>
>
> 	* gthr-single.h (__GTHREAD_MUTEX_INIT_FUNCTION): Use braces
> 	instead of macro's empty body to avoid xgcc warnings.
OK for the trunk.

jeff

Re: [PATCH v2] libgcc: Use braces instead of macro's empty body to avoid xgcc warnings.

[Jeff Law]

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This patch was originally from Chen Gang S.  However, his address at 
sunrus.com.cn bounces.  So presumably he didn't get the approved 
message.  I'm checking in the patch for him (with the fixed ChangeLog).

I've verified by hand that the warning goes away with a cross toolchain 
and that it doesn't affect x86_64-unknown-linux-gnu.




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