Re: [boost] Why Boost.Build?

Subject: Re: [boost] Why Boost.Build?
From: Fabio Fracassi (f.fracassi_at_[hidden])
Date: 2011-03-30 13:09:19

On 30/3/2011 10:36, Artyom wrote:
>
>
>
>> Even though I was the one who contributed to the increase of
>> end  users dealing with BBv2, with the creation of the
>> build&install support, I've  always been a proponent that having users
>> rely on the Boost build setup is a  bug. I.e. users should be able
>> to drop source code into their own build system  without *any* other
>> extra effort. And the fact that many Boost libraries can't  do that is sad.
>>
>> So Boost end users should *not* be the primary  audience!
>>
>
> Actually I must admit it is wrong statement. Why? Because
> the libraries may be much more complicated then you think.
>
> Especially when it comes to handling DLL's where you need a special
> defines for DLL build.
>
> But this is only 5% of the problem.
>
> If you try for example build boost-system or other relatively
> simple libraries that do not have any external dependencies
> it is simple.
>
> Now when it comes to iostreams or regex it becomes more complicated
> (zlib, bzip2 and icu)
>
> Now lets take few other libraries that are now in review queue:
>
> - Boost.Context - it has platform/compiler conditional assembly sources
>    and separate build options to use ucontext or fcontext.
>
>    Do you really think it is possible to give a user sources and say
>    compile them?
>
> - Boost.Locale - it depends on several libraries: ICU, iconv and boost-thread
>    conditionally has 5 build options (with/out icu,iconv,win32api,posix-api,
>    std-locale-api) and some of them should be turned conditionally for different
>    platforms.
>
> So no I don't expect user to do all the job for me. This is why build
> system exists.
>
> Boost is lucky because its libraries and build are relatively simple.
> and before anybody screams about how sophisticated boost is I add
>
> - Almost no compile time configuration (something like generated config.h)
> - Almost no 3rd part dependencies.
> - Almost all configuration is done by ifdefs instead of configure like
>    scripts that can test features automatically and not require from
>    user to know every possible OS/Compiler setup.
>
> So that is why Boost.Build suites somehow Boost and in general
> this is why build system exist.

Absolutely.

>
> A friend of mine that works with MSVC Projects only do not understand
> all buzz around makes/cmakes/autotools/bjams and so on because
> he writes software for one compiler and one platform... So MSVC projects
> suit him.
>

Even then I would probably use CMake to automate finding of External 
libs (i.e. Boost), especially if one has several subprojects.

> But in real world Build system is essential part of any project.

+1

Especially for Library development, where the user is always also developer.

regeards

Fabio