Re: [jamboost] Re: I'm back!

From: David Abrahams (dave_at_[hidden])
Date: 2002-10-14 12:29:12

Vladimir Prus <ghost_at_[hidden]> writes:

> David Abrahams wrote:
> 
> I'm bad at writing comments, it seems, either in full or in parts :-)
> I'll try to explain semantic verbosely.

Sometimes that's the best answer for the comments, too ;-)

> If you call 'generate' with full property set, in means to build it
> with those properties. 

By "full property set", do you mean one where all non-optional
features are represented? Or do you mean something else?

> For example, this happens when there's a list of properties in the
> command line, and the abstract target is directly requested.
> 
> If you call 'generate' with a property set containing only
> <toolset>, it means to build it using the given toolset, and using
Suggest rephrase: "only <toolset>xxx"
> some default set of property sets. For example, when called with
> "<toolset>gcc", a target with default build of "debug release" will
> build itself with two property sets
> 
> <toolset>gcc <variant>debug ...
> <toolset>gcc <variant>release ...
> 
> Why special treatment for toolset? In V1 default build is done using
> all available toolsets. In other words, a target with default build
> "debug" can be build with <toolset>gcc and
"built"----------^^^^^
> <toolset>borland. Currently, main target's generate simply calls
> 'build-request.expand' with the value of it's default build
"its"--------------------------------------^^^^
> attribute. And 'build-request.expand' can't return property sets
> with different values of <toolset>, unless explicit list of
> <toolset> properties is passed to it. I thought this handling of
> predefined set of toolsets in better done at the high level, not
> inside main-target.
> 
> However, do we really need such semantics? 

IMO, no.

> In general, we don't build two variants unless explicitly
> asked. Maybe, we can build with "default" toolset, unless asked
> otherwise? 

Yes.

> IE, on my Linux box, "bjam" will build with gcc, and msvc will be
> used for someone else?

Total agreement.

It should probably use user-config.jam and site-config.jam and then
fall back to platform-specific behavior. On Windows it should probably
check the registry for known compilers (yes, there's a Jam extension
for this out there) and auto-select if there's only one, notify
otherwise.

-Dave