as the first elements of result. Those usage requirements will be combined
with explicitly specified for the main target.
This is yet another step towards making 'main target classes' unnecessary.
* build/generators.jam
(try-one-generator): Check if generator returned usage requirements or not.
(construct): Make sure first element of result is always property set.
(many other methods): Induced changes
* tools/builtin.jam
(exe-target-class, lib-target-class): Remove.
(linking-generator, seached-lib-generator): Compute usage requirements.
(archiving-generator): New class
[SVN r26192]
write
using gcc : ... : ... : <cxxflags>foo <linkflags>bar ;
* tools/common.jam (handle-options): The login for setting the common
options.
[SVN r25767]
