Re: [jamboost] Dependencies & generated headers

From: David Abrahams (dave_at_[hidden])
Date: 2002-09-10 07:47:26

From: "Vladimir Prus" <ghost_at_[hidden]>

> Say a source file a.cpp has
>
> #incude "a_parser.h"
>
> and "a_parser.h" is generated by some build action and placed into build
> dir. We need two things to make it
> work
> 1. Add the directory where a_parser.h is placed to the include path when
> compiling a.cpp

In Boost.Build v1 this is done indiscriminately.

> 2. Make sure a.cpp depends on "a_parser.h". This can be quite simply
> accomplished if the dependency scanner
> will check is there's intermediate file called "a_parser.h" in the
> dependency graph for the given main target.

I don't understand why this is so complicated. It already works in
Boost.Build v1.
Why would we need to check for intermediate files?
It just puts a_parser.h in the dependency graph and sets SEARCH
appropriately so it can be found.

> There's a question:
>
> exe a : a.cpp ;
> exe b : b.cpp a.whl ;
>
> Here, a_parser.h will be generated when constructing main target b, and
> we can't reliable set a dependency from
> a.cpp to a_parser.h. I think this is not a big problem.
>
> Are there any objections to the above ideas?

I guess I still don't understand what you're proposing.

-----------------------------------------------------------
David Abrahams * Boost Consulting
dave_at_[hidden] * http://www.boost-consulting.com