Re: [RFC PATCH] explicitly mark recursion count

[Jörn Engel]

On Wed, 2 June 2004 16:20:24 -0700, Davide Libenzi wrote:
> 
> Think at file_operations as very simple example, and try to find out what 
> is actually called when somewhere the code does f_op->*(). How would you 
> build the graph down there. You'd have to record all the functions that 
> have been assigned to such method throughout the code, and nest *all* 
> their graph in place. And this will eventually trigger false positives. 

Bad example, I can deal with that just fine. :)
Any code calling f_op->read must not break for any f_op->read.  So it
is perfectly sane to assume that all get called.  I build the graph by
turning f_op->read into a pseudo-function that calls all functions
ever assigned to f_op->read.

> Similar thing with functions that accepts callbacks, either directly or 
> inside structures.

Those I only handle, if the callbacks are inside structures, true.
Will fix it when I find the time for it.

> And this doesn't even start to take aliasing into 
> account.

What exactly do you call aliasing?  Do you have an example?

> Hunting stack hungry functions is very good, and having a tool 
> that is maybe 60% precise in detecting loops is fine too. But requiring 
> metadata to be maintained to support such tool is IMO wrong.

Since Linus feels that said metadata is still useful without any
tools, I'll just ignore this objection. ;)

Still, some of the complaints were valid, thanks a bunch!  My todo
list has grown again.

Jörn

-- 
Write programs that do one thing and do it well. Write programs to work
together. Write programs to handle text streams, because that is a
universal interface. 
-- Doug MacIlroy
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