Toolsets: 'flags' rule

From: Vladimir Prus (ghost_at_[hidden])
Date: 2002-11-10 09:51:33

I'm about to implement the V2 version of "flags" rule, and there's
my vision of it. On the whole, I'll retain the V1 interface, with the
only change. Instead of

flags tools-name variable-name condition .....

I'll use

flags rule-name variable-name condition .....

Note that every build action in V2 is associated with a rule that
sets this build action up and those rules have nice names like gcc.link.
We'll just specify flags on per-rule basis:

flags gcc.link CFLAGS <debug-symbols>true : -g ;

To allow flags that apply to all rules for toolset, we'd allow

flags gcc GXX-VERSION <version> ;

to apply to each rule in "gcc" module.

Specifically, virtual-target.action in 'actualize' method will call
new rule 'toolset.set-target-variables' with the name of rule.
'set-target-variables' will apply flags which either have the same rule
name, or which refer to the rule's module.

Does the above sounds right? I'm going to implement this right now, but
it's quite simple, so I can change implementation later.

- Volodya