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Subject: Re: [Boost-build] bjam 4.0.. in C++
From: Michael Jackson (mike.jackson_at_[hidden])
Date: 2010-05-27 13:59:35

On 5/27/10 1:41 PM, in article 4BFEAEB7.8040304_at_[hidden], "Matt
Chambers" wrote:

> Spencer E. Olson wrote:
>> All,
>> I'd like to hear feedback with regards to the future of Boost.Build/bjam. A
>> colleage recently attended BoostCon and came back with the impression that
>> Boost.Build would be replaced by Kitware's CMake for Boost's primary build
>> system. Apparently, someone asked "who uses Boost.Build in non-Boost
>> programming" and very few people raised their hands. On the other hand,
>> after the question "who uses cmake in non-Boost packages" and several people
>> raised their hand.
> I use BBv2 with a multi-tiered cross-platform project: Bumbershoot
> depends on ProteoWizard which depends on Boost. These projects are quite
> loosely coupled. All of them are built with BBv2. We even use Rene's
> extensions system so we build things like zlib and expat from BBv2. We
> don't rely on the user already having something installed. We easily
> bootstrap and build our own copy of bjam if it's not already built:
> The advantage of bjam in this case is it's extremely fast to bootstrap.
> I'd be worried about a bjam port based on heavy use of C++ templates and
> meta-programming which takes a long time to compile. CMake would be
> almost as bad. It's hard to imagine actually bootstrapping it: is there
> anyone who actually does that? Like others, I'd like to bjam be faster
> at dependency scanning. Although I don't have the profiling statistics
> that Rene asked for, I've never gotten the sense that bjam was very
> memory heavy except in the case of complex dependency graphs where it
> will sometimes use gigs of memory.
> I certainly want to see BBv2 used in favor of CMake because it's mostly
> declarative. I dislike the morass of procedure calls in a CMake
> makefile. I will echo others' obvious sentiments of dissatisfaction with
> bjam error messages and syntax pickiness. Although that's not news. :)
> I'm very grateful for Rene and Volodya's continued efforts on BBv2.
> However, I'm somewhat more supportive of Volodya's effort to port BB's
> higher level logic from Jam to Python than I am of replacing bjam's low
> level C parsing code with C++, even if it would mean the parser was
> easier to maintain. Also, isn't it easier to call simple C routines from
> Python than it is to call C++ when high performance is needed?
> -Matt

I bootstrap it (CMake) all the time when a new release comes out. I have
bootstrapped it on everything from consumer grade PCs to SGI, Linux, Sun and
CrayXT based super computers. Yes it does take a bit longer to compiler than
bjam, but it can be bootstrapped without a problem. Just FYI. Now back to
the normal conversation.

Mike Jackson

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