Conditional property validation (Was: [jamboost] [v2] broken)

From: Vladimir Prus (ghost_at_[hidden])
Date: 2004-05-27 03:00:15

Hi Jürgen,

Jürgen Hunold wrote:
> lib boost_test_exec_monitor : $(TEST_EXEC_MON_SOURCES).cpp
>
> : <toolset>borland:<cxxflags>-w-8080
>
> ;
>
> This breaks with the following message:
>
> error: "borland" is not a known value of feature <toolset>
> legal values: "gcc"
>
> when no "using borland ;" is specified in user-config.jam or elsewhere.
>
> I think this is a know issue, isn't it ?

No, this is not a known issue and it fact I've introduced the regression (?) 
yesterday. Until now, the properties inside condition (the <toolset>borland 
part above) was not checked for correctness at all. While fixing another bug, 
I've accidentally caused it to be checked.

Now the question:

Do we need validation for condition?

For example, if we have:

<toolset>msvc:<cflags>...

it's possible to ask user to have "using msvc ; " somewhere. But that might 
cause warnings that msvc is not found. Further, for

<toolset>msvc-7.1:<cflags>...

user should declare *specific* version of toolset.. It's hard to do that 
inside boost's project-root.jam, because it's not clear what path to use, for 
example, and how the user can configure the same version in user-config.jam

So, we've two choices:

1. Don't validate condition at all
2. Provide the means for user to say: 'msvc-7.1' is OK as the value. This, 
however, might be very tricky, since "msvc-7.1' is really a shortcut for

<toolset>msvc <toolset-msvc:version>7.1

and asking the user to define the above properties as valid is too much. 
Opinions?

> Btw: Where do I put my "user-config.jam" on Win32 ?

http://boost.sourceforge.net/boost-build2/boost_build_v2.html#initialization

says it should be either in %HOME% or %BOOST_BUILD_PATH%, which means you have 
to set either of this variables. The site-config.jam file can be put in 
%SystemRoot% which should be defined already.

HTH,
Volodya