overriding CXX_FLAGS

[Mattia Verga]

In the latest version of RawTherapee, developers suggest the use of 
-DCMAKE_CXX_FLAGS="-std=c++11".

I've tried to modify the .spec file with 
-DCMAKE_CXX_FLAGS="$RPM_OPT_FLAGS -std=c++11" [1], but koji still use 
"-std=c++11 -std=gnu++11" [2] and the latter wins (I think).

How can I override that setting?

Thanks
Mattia

[1] https://mattia.fedorapeople.org/rawtherapee.spec
[2] https://koji.fedoraproject.org/koji/taskinfo?taskID=17398942

[Dan Horák]

On Tue, 24 Jan 2017 08:06:14 +0100
Mattia Verga <mattia.verga(a)tiscali.it&gt; wrote:

>  In the latest version of RawTherapee, developers suggest the use of 
>  -DCMAKE_CXX_FLAGS="-std=c++11".
>  
>  I've tried to modify the .spec file with 
>  -DCMAKE_CXX_FLAGS="$RPM_OPT_FLAGS -std=c++11" [1], but koji still use 
>  "-std=c++11 -std=gnu++11" [2] and the latter wins (I think).
>  
>  How can I override that setting? 
no need to override the flags, RawTherapee sets -std=gnu++11 for you in
https://github.com/Beep6581/RawTherapee/blob/master/CMakeLists.txt#L23


		Dan

[Mattia Verga]

Il 24/01/2017 08:25, Dan Horák ha scritto:
>  no need to override the flags, RawTherapee sets -std=gnu++11 for you in
>  https://github.com/Beep6581/RawTherapee/blob/master/CMakeLists.txt#L23
>
>
>  		Dan
>  _______________________________________________
>  devel mailing list -- devel(a)lists.fedoraproject.org
>  To unsubscribe send an email to devel-leave(a)lists.fedoraproject.org 
Ah, thanks, I
missed that.

I must ask developers why they recommend to use c++11 and then they set 
it fixed to gnu++11....

[Jan Kratochvil]

On Tue, 24 Jan 2017 10:54:32 +0100, Mattia Verga wrote:
>  I must ask developers why they recommend to use c++11 and then they
> set it
>  fixed to gnu++11.... 
gnu++11 is a superset of c++11 so that should work either.

Older GCCs defaulted to c++98, they may mean the project requires compiler
supporting c++11.

But you should not need any -std=... specification in recent Fedoras:

GCC 6.0: https://gcc.gnu.org/gcc-6/changes.html
The default mode for C++ is now -std=gnu++14 instead of -std=gnu++98.

(Also gnu++14 is a superset of gnu++11 and therefore also c++11.)


Jan

[Ben Boeckel]

On Tue, 24 Jan, 2017 at 07:06:14 GMT, Mattia Verga wrote:
>  In the latest version of RawTherapee, developers suggest the use of 
>  -DCMAKE_CXX_FLAGS="-std=c++11".
>
>  I've tried to modify the .spec file with 
>  -DCMAKE_CXX_FLAGS="$RPM_OPT_FLAGS -std=c++11" [1], but koji still use 
>  "-std=c++11 -std=gnu++11" [2] and the latter wins (I think).
>
>  How can I override that setting? 
Since it is a CMake package, it would be better to do:

    -DCMAKE_CXX_STANDARD=11
    -DCMAKE_CXX_STANDARD_REQUIRED=TRUE

This uses CMake's flag logic rather than hard-coding a flag.

There is also:

    -DCMAKE_CXX_EXTENSIONS=OFF

(on by default because compilers tend to default to using extensions) to
disable the GNU extensions.

It would be good for upstream to use these rather than manipulating
flags manually.

--Ben