creating multiple outputs with a tool in one step

[James McElhannon]

Suppose I have a file A that is dependent on B and C.  I have a tool, mytool, that can create B and C at one time from their respective sources.  When making A, I would want make to do "mytool B C" as one of its steps.

 

A.y: B.z C.z

    ... steps for A ...

    mytool B.z C.z

    ... steps for A...

 

%.z:

    mytool ...

 

 

mytool has a big startup time, so the time to do two runs, one for B and one for C, is *much* longer than doing them both at once (which is why the tool was created to create multiple outputs in one run).

 

If I try to use the pattern for %.y, then I get multiple runs for mytool.  If I hardcode the target A, then I can get it to work since I have control over everything.

 

How can I do this?

 

Thanks in advance,

James