[x265] [PATCH 1/2] weight prediction: use sqrtf

[Steve Borho]

On Thu, Mar 6, 2014 at 1:04 PM, Rafaël Carré <funman at videolan.org> wrote:
> On 03/06/14 18:56, Steve Borho wrote:
>> On Thu, Mar 6, 2014 at 11:44 AM, Rafaël Carré <funman at videolan.org> wrote:
>>> On 03/05/14 18:06, Steve Borho wrote:
>>>> On Wed, Mar 5, 2014 at 4:38 AM, Rafaël Carré <funman at videolan.org> wrote:
>>>>> ---
>>>>>  source/encoder/weightPrediction.cpp | 2 +-
>>>>>  1 file changed, 1 insertion(+), 1 deletion(-)
>>>>>
>>>>> diff --git a/source/encoder/weightPrediction.cpp b/source/encoder/weightPrediction.cpp
>>>>> index c04361a..c0710fd 100644
>>>>> --- a/source/encoder/weightPrediction.cpp
>>>>> +++ b/source/encoder/weightPrediction.cpp
>>>>> @@ -203,7 +203,7 @@ bool WeightPrediction::checkDenom(int denom)
>>>>>                  uint64_t fencVar = fenc->wp_ssd[yuv] + !ref->wp_ssd[yuv];
>>>>>                  uint64_t refVar  = ref->wp_ssd[yuv] + !ref->wp_ssd[yuv];
>>>>>                  if (fencVar && refVar)
>>>>> -                    guessScale[yuv] = Clip3(-2.f, 1.8f, std::sqrt((float)fencVar / refVar));
>>>>> +                    guessScale[yuv] = Clip3(-2.f, 1.8f, sqrtf((float)fencVar / refVar));
>>>>
>>>> Is something wrong with std::sqrt?
>>>
>>> I got:
>>> x265/source/encoder/weightPrediction.cpp:206:57: error: 'sqrt' is not a
>>> member of 'std'
>>>
>>> With g++ 4.8.2
>>>
>>> Full command line is :
>>>
>>> cd /home/fun/x265/source/encoder && /usr/bin/c++   -DHAVE_INT_TYPES_H=1
>>> -DHIGH_BIT_DEPTH=0 -DLOG_CU_STATISTICS=0 -DX265_ARCH_X86=1 -DX86_64=1
>>> -O2 -g -DNDEBUG -I/home/fun/x265/source/. -I/home/fun/x265/source/Lib
>>> -I/home/fun/x265/source/common -I/home/fun/x265/source/encoder
>>> -I/home/fun/x265/source    -Wall -Wextra -Wshadow -ffast-math
>>> -mstackrealign -fPIC -o CMakeFiles/encoder.dir/weightPrediction.cpp.o -c
>>> /home/fun/x265/source/encoder/weightPrediction.cpp
>>>
>>> Perhaps I am missing a -stdc++=something that was added later?
>>
>> No, I don't believe so.  I build this regularly with gcc 4.8.1 on both
>> Linux and MinGW.
>>
>> http://en.cppreference.com/w/cpp/numeric/math/sqrt
>>
>> Does adding #include <cmath> to the file help?
>
> Yes, no problem if <cmath> is included.

Thanks Rafaël,

I see that math.h is included in several cpp files and a couple of
headers.  I think I'll include cmath in common.h and remove all the
others.

-- 
Steve Borho