On 3/22/2017 11:01 PM, James Almer wrote:
> On 3/22/2017 10:01 PM, Michael Niedermayer wrote:
>> On Wed, Mar 22, 2017 at 08:34:05PM -0300, James Almer wrote:
>>> This set deals with most of the remaining cases of libavutil/atomic.h usage.
>>> "make fate THREADS=4" passes here on mingw-w64, but I'm not 100% sure fate
>>> has proper coverage of some of these functions.
>>>
>>> Only ones remaining are Decklink (It's C++98 and I'm not sure how wise would
>>> it be to include a C11 header in there, so i'm leaving that to someone
>>> else),
>>> and error_resilience.
>>>
>>> James Almer (7):
>>> avcodec/mediacodec: convert to stdatomic
>>> avcodec/utils: convert to stdatomic
>>> avcodec/parser: convert to stdatomic
>>> avformat/format: convert to stdatomic
>>> avfilter/avfilter: convert to stdatomic
>>> avutil/opencl: convert to stdatomic
>>> avcodec/videotoolboxenc: remove unused atomic header
>>>
>>> libavcodec/mediacodec.c | 5 ++---
>>> libavcodec/mediacodecdec.c | 1 -
>>> libavcodec/mediacodecdec_common.c | 14 ++++++--------
>>> libavcodec/mediacodecdec_common.h | 5 +++--
>>> libavcodec/parser.c | 14 ++++++++++----
>>> libavcodec/utils.c | 19 +++++++++++--------
>>> libavcodec/videotoolboxenc.c | 1 -
>>> libavfilter/avfilter.c | 6 ++++--
>>> libavformat/format.c | 9 ++++++---
>>> libavutil/opencl.c | 5 +++--
>>> 10 files changed, 45 insertions(+), 34 deletions(-)
>>
>> This breaks building with clang
>>
>> CC libavfilter/avfilter.o
>> CC libavformat/format.o
>> CC libavcodec/parser.o
>> CC libavcodec/utils.o
>> src/libavformat/format.c:68:51: error: address argument to atomic operation
>> must be a pointer to _Atomic type ('AVInputFormat **' (aka 'struct
>> AVInputFormat **') invalid)
>> while(p != &format->next && !format->next &&
>> !__c11_atomic_compare_exchange_strong(p, &cmp, format, 5, 5))
>> ^
>> ~
>> src/libavformat/format.c:81:51: error: address argument to atomic operation
>> must be a pointer to _Atomic type ('AVOutputFormat **' (aka 'struct
>> AVOutputFormat **') invalid)
>> while(p != &format->next && !format->next &&
>> !__c11_atomic_compare_exchange_strong(p, &cmp, format, 5, 5))
>> ^
>> ~
>> 2 errors generated.
>> make: *** [libavformat/format.o] Error 1
>
> Casting the first argument to (atomic_intptr_t *) on GCC 6 gives me a warning
> about making integer from pointer, but still works nonetheless.
>
> I'm not sure how to fix this. Got any idea?
Does the attached patch compile with Clang? GCC 6 seems happy with it.
It's getting kind of ugly in any case.
>From 3bf230d5f611ae5d1511e4629f742fc96b379b7f Mon Sep 17 00:00:00 2001
From: James Almer <jamr...@gmail.com>
Date: Wed, 22 Mar 2017 23:43:54 -0300
Subject: [PATCH] avformat/format: convert to stdatomic
---
libavformat/format.c | 9 ++++++---
1 file changed, 6 insertions(+), 3 deletions(-)
diff --git a/libavformat/format.c b/libavformat/format.c
index 38ca2a3465..781f341936 100644
--- a/libavformat/format.c
+++ b/libavformat/format.c
@@ -19,7 +19,8 @@
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
-#include "libavutil/atomic.h"
+#include <stdatomic.h>
+
#include "libavutil/avstring.h"
#include "libavutil/bprint.h"
#include "libavutil/opt.h"
@@ -61,9 +62,10 @@ AVOutputFormat *av_oformat_next(const AVOutputFormat *f)
void av_register_input_format(AVInputFormat *format)
{
AVInputFormat **p = last_iformat;
+ const AVInputFormat *cmp = NULL;
// Note, format could be added after the first 2 checks but that implies that *p is no longer NULL
- while(p != &format->next && !format->next && avpriv_atomic_ptr_cas((void * volatile *)p, NULL, format))
+ while(p != &format->next && !format->next && !atomic_compare_exchange_strong((atomic_intptr_t *)p, (intptr_t *)&cmp, (intptr_t)format))
p = &(*p)->next;
if (!format->next)
@@ -73,9 +75,10 @@ void av_register_input_format(AVInputFormat *format)
void av_register_output_format(AVOutputFormat *format)
{
AVOutputFormat **p = last_oformat;
+ const AVOutputFormat *cmp = NULL;
// Note, format could be added after the first 2 checks but that implies that *p is no longer NULL
- while(p != &format->next && !format->next && avpriv_atomic_ptr_cas((void * volatile *)p, NULL, format))
+ while(p != &format->next && !format->next && !atomic_compare_exchange_strong((atomic_intptr_t *)p, (intptr_t *)&cmp, (intptr_t)format))
p = &(*p)->next;
if (!format->next)
--
2.12.0
_______________________________________________
ffmpeg-devel mailing list
ffmpeg-devel@ffmpeg.org
http://ffmpeg.org/mailman/listinfo/ffmpeg-devel
