[108385] trunk/dports/gis/gdal/Portfile

[Ryan Schmidt]

On Jul 22, 2013, at 11:58, Vincent Habchi wrote:

> Le 22 juil. 2013 à 14:52, Ryan Schmidt a écrit :
> 
>> Possibly you should set "configure.optflags -O3 -march=native" instead of dealing with cflags and cxxflags directly.
> 
> I found that setting configure.cflags and cxxflags does not seem to interfere with the other options. But if you say there is a more suitable way to set them, I’ll abide by your advice.

The default for configure.optflags is -Os in MacPorts 2.2 and was -O2 previously.
The default for configure.cflags, configure.cxxflags, configure.objcflags, configure.objcxxflags, configure.fflags, configure.f90flags, and configure.fcflags is ${configure.optflags}.
Furthermore, if configure.pipe is true, "-pipe" is prepended to these. This setting can be influenced from macports.conf via the configurepipe setting. The default used to be false, but was changed to true in r59582 in 2009.
So since it is your intention to change the optimization flags, you should set configure.optflags, and not assume the user has configurepipe set to true.


>> Or possibly users who want performance should edit this and the compiler choice into macports.conf directly. However they would also have to disable the use of the precompiled binaries otherwise they would, without warning, receive a binary that was not compiled with those flags. So I could understand if we don't think that's the best solution.
> 
> Exactly. The idea I had is that the users that want their ports to be compiled and optimized for their machine should add the +perf variant in variants.conf. Since +perf is never enabled by default, this would never result in the fetching of the pre-compiled binaries. What do you think?

I think that's true. I just wanted to avoid using variants for something if we already handle it at the MacPorts base level. But maybe we don't completely handle it there.

I *thought* we already had a setting in macports.conf for overriding configure.optflags, but I cannot find it described in macports.conf.default. Maybe I was imagining that.

I know we have a setting in macports.conf for overriding configure.compiler but that we deliberately do not advertise it because it's not something we wanted users to get into the habit of doing.

If we have settings for overriding configure.optflags and configure.compiler, then maybe doing so should automatically disable the use of binaries.