How to create header files before make(1) tries to build-headers

[Chris Vetter]

Hi,

problem is that for a framework I need to create a couple of files via 
yacc(1) (yes, I know, don't ask) that include needed 'official' header 
files (that is, the header files will get installed later on). Now, 
easy (I thought) just create them via 'before-all::' in 
GNUmakefile.postamble. This works -- as long as make(1) is called 
inside the subproject directory that contains the yacc(1) files.
If I run make(1) at top level, it will step through each subproject 
directory and tries to copy the header files -- which do yet not 
exist, because for some reason, 'before-all::' doesn't get 'executed' 
before all. Uhm.

So, question is, how can I have yacc(1) run before make(1) tries to 
copy the (not yet existing) header files???
No, having to run sth like 'make -f Makefile.yacc' first is not really 
an option...

--
Chris