rather then only defined on first.
The previous behaviour did not work when there were "default-build" attribute
on project and two alternatives for a main target.
Patch from Michael Stevens.
[SVN r19303]
default build was stored as plain list, and implied properties were not
converted. E.g. we had "debug release", not "<variant>debug <variant>release",
which was assumed.
* new/targets.jam
(main-target, basic-target): Store 'property-set' as default-build
attribute.
(main-target-default-build): Use 'property-set.create-with-validation'.
* new/property-set.jam
(create-with-validation): New rule.
* test/default_build.py: More tests.
[SVN r18436]
* new/targets.jam
(main-target.default-build): New field.
(main-target.add-alternative): Don't allow default-build for
second and subsequence alternatives. Record default build
from the first one.
(main-target.generate): Expand build request.
(main-target.generate-really): New rule, extracted from 'generate'.
(basic-target.default-build): New rule.
(basic-target.generate): Don't expand default build.
* test/BoostBuild.py
Allow to suppress passing toolset when calling run_build_system.
Some Python 2.1 compatibility fixes.
* test/alternatives.py
More tests.
* test/default_build.py
More tests.
[SVN r17683]
