On Thu, Aug 31, 2017 at 02:07:43PM -0400, Mark Wachsler wrote: > Memory reallocated with av_reallocp_array is supposed to be allocated > with av_realloc, not av_malloc.
Our docs did briefly claim this but it was removed years ago in
21f70940ae106bfffa07e73057cdb4b5e81a767a
Also FFmpeg has been written with av_realloc*() and av_malloc*()
compatibility in mind both before and after
21f70940ae106bfffa07e73057cdb4b5e81a767a
So its not 2 but many more that likely would need to be changed
If there is a incompatibility then
Its easier to fix the incompatibility between av_malloc* and av_realloc*
also it is much more maintainable if they are compatibile.
Code that works on 99.9 % of the developers systems but breaks on the
remaininng 0.1% is really hard to maintain design.
That said iam not against this patch and i can apply it (without tabs)
if people want but this is far from fixing all these issues
DId you try to replace posix_memalign() by aligned_alloc() where its
available?
ISO C requires aligned_alloc() to be compatibile with realloc()
where one can debate the situation of posix_memalign() and realloc()
For reference
7.22.3 Memory management functions
...
7.22.3.1 The aligned_alloc function
Thus aligned_alloc() is a "Memory management function" in ISO C
In the list of undefined behaviors there is:
- The pointer argument to the free or realloc function does not match a
pointer
earlier returned by a memory management function, or the space has been
deallocated
by a call to free or realloc (7.22.3.3, 7.22.3.5).
The undefined behavior is clearly limited to pointers not originating
from "Memory management functions", I can see no special case for
aligned_alloc()
In case your implemnatation of aligned_alloc() and realloc() are
incompatibile as well, please fix your implemnatation.
Thanks
[...]
--
Michael GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB
While the State exists there can be no freedom; when there is freedom there
will be no State. -- Vladimir Lenin
signature.asc
Description: Digital signature
_______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-devel
