Re: [Boost-build] [1.35] what gets built and installed?

From: Rush Manbert (rush_at_[hidden])
Date: 2007-12-19 16:37:28

John Maddock wrote:
> Rene Rivera wrote:
> 
>>John Maddock wrote:
>>
>>>If I do a:
>>>
>>>bjam stage --toolset=msvc-8.0 --with-regex
>>>
>>>Then with 1.35 I don't get any static libraries built, just the
>>>dll's.  Was this a deliberate change somewhere?  It's a problem
>>>because the default for auto-linking is to look for static rather
>>>than dynamic libraries.
>>
>>Yes, it was intentional
>><http://article.gmane.org/gmane.comp.lib.boost.devel/168552>. We also
>>discussed it at one point
>><http://article.gmane.org/gmane.comp.lib.boost.devel/166847>. I guess
>>we
>>should switch autolink to default to the dynamic libs?
> 
> 
> That's actually not possible without changing folks library code: it's a 
> per-library decision which is the default, with the static library being 
> recomended as the default unless there are reasons to choose otherwise. 
> There's a great deal of documentation that would have to change to reflect 
> this as well.
> 
> There's also a rationale for why static linking is the default behaviour in 
> our docs here: 
> http://www.boost.org/more/separate_compilation.html#static_or_dynamic
> 
> There's a further issue with building only one variant under MSVC: it 
> doesn't work!
> 
> By only building a release build, then the only thing that will work 
> "straight out the box" is building a release build of your application 
> against the dll runtime.  Debug builds will generate linker errors (can't 
> find the auto-linked library etc), as will builds against the static 
> runtime, this means that Boost will appear totally broken if users try and 
> build the default debug builds that their IDE gives them.
> 
> We need to be *very* careful with this, or the complaints will be loud and 
> vociferous!
> 
> If the aim is to reduce the number of variants built, then I would suggest:
> 
> Dymanic *and* static lib, as Release, multithreaded, dynamic runtime single 
> build on Unix variants (2 build variants).
> Dynamic *and* static lib, Release *and* Debug, multithreaded, dynamic 
> runtime on Win32 compilers (that's 4 build variants).
> 
> That's an absolute minimum IMO.  Even then we will have to be very careful 
> that our build instructions indicate very clearly how to build the other 
> variants, especially for those msvc users :-)
> 
> Sorry to be the bearer of the bad news,
> 
If a user may be permitted to comment, I think John is correct here. It 
is far better that the boost build take a long time (with a big warning 
in the build instructions to that effect) but build all of the normally 
used variants than having it build only Release shared libraries.

My guess is that most Boost users are developing for deployment to their 
users, and many of them will want their apps to be statically linked to 
Boost libraries, among others, in order to avoid a whole host of issues. 
I also can't believe that anyone who uses an IDE for development doesn't 
build Debug versions much more often, and usually by default, than they 
build Release versions. This is certainly true for MSVC and Xcode users.

I think you will get many complaints and spend a lot of time answering 
the "how do I build static libraries on platform x" and "how do I build 
debug libraries" posts if you change the default. If you do change the 
default behavior to build only Release shared libraries, then you need 
to make it dead simple to build all of the variants.

Best regards,
Rush