Looking for speed increases in "make index" and pkg_version for ports

[Stephen Montgomery-Smith]

I have been thinking a lot about looking for speed increases for "make 
index" and pkg_version and things like that.  So for example, in 
pkg_version, it calls "make -V PKGNAME" for every installed package. 
Now "make -V PKGNAME" should be a speedy operation, but the make has to 
load in and analyze bsd.port.mk, a quite complicated file with about 
200,000 characters in it, when all it is needing to do is to figure out 
the value of the variable PKGNAME.

I suggest rewriting "make" so that variables are only evaluated on a 
"need to know" basis.  So, for example, if all we need to know is 
PKGNAME, there is no need to evaluate, for example, _RUN_LIB_DEPENDS, 
unless the writer of that particular port has done something like having 
PORTNAME depend on the value of _RUN_LIB_DEPENDS.  So "make" should 
analyze all the code it is given, and only figure it out if it is needed 
to do so.  This would include, for example, figuring out .for and .if 
directives on a need to know basis as well.

I have only poked around a little inside the source for make, but I have 
a sense that this would be a major undertaking.  I certainly have not 
thought through what it entails in more than a cursory manner.  However 
I am quite excited about the possibility of doing this, albeit I may 
well put off the whole thing for a year or two or even forever depending 
upon other priorities in my life.

However, in the mean time I want to throw this idea out there to get 
some feedback, either of the form of "this won't work," or of the form 
"I will do it," or "I have tried to do this."

Best regards, Stephen