Re: [boost] CMake - one more time

Subject: Re: [boost] CMake - one more time
From: Robert Ramey (ramey_at_[hidden])
Date: 2016-04-28 01:04:28

On 4/27/16 6:47 PM, Gavin Lambert wrote:
> On 27/04/2016 06:02, Robert Ramey wrote:
>> LOL - see my rant about option() above.  it's not clear where one should
>> put it, how it interacts with option placed somewhere else, whether the
>> options are string variables or some sort of instrinsic, what is the
>> default, how it interacts with someone placing the option on the command
>> line.  This is just a tiny simple example and a very simple one compared
>> to others.  One could supply pages and pages and pages of such examples
>> - but thankfully one is sufficient.
>
> https://cmake.org/cmake/help/v3.0/command/option.html
>
> It seems fairly obvious how they're defined from that.

LOL - sorry it's not obvious to me. It still doesn't answer the 
questions that occured to me above.

>
> Usually custom options would be activated with -d

You mean a command line switch?  How would one do this with the GUI.

> and tested for with if
> (https://cmake.org/cmake/help/v3.0/command/if.html), but
> BUILD_SHARED_LIBS in particular
> (https://cmake.org/cmake/help/v3.0/variable/BUILD_SHARED_LIBS.html)
> alters the behaviour of add_library
> (https://cmake.org/cmake/help/v3.0/command/add_library.html) when
> defined (via any means).
>
> ie. add_library(name STATIC sources...) will always build a static library.
>     add_library(name SHARED sources...) will always build a shared library.
>     add_library(name sources...) will build a shared library if
> BUILD_SHARED_LIBS is ON, otherwise a static library.
>
> This information was not hard to find.

LOL - it's not that it's hard to find - it's hard to make sense of when 
you do find it.  Ambiguity is built in.

Of course it's a matter of opinion.  If it's clear to you, I won't 
dispute it.

Robert Ramey