[Cocci] [PATCH] coccinelle: assign signed result to unsigned variable

[elfring@users.sourceforge.net (SF Markus Elfring)]

> Generally I want to catch all assignments of signed function result to unsigned var.

Such a static source code analysis will be useful to some degree.


> In this script I have implemented it this way:
> 1. Look for all assignments 'unsigned = signed' (rs rule).
> 2. Check if signed from rs rule looks as a function call.

I recommend to reconsider a few implementation details because I have got
the impression that this check sequence is inappropriate.


> Is there better way to do it?

I suggest to fix expression weaknesses and a design mistake in this SmPL approach.

I guess that you want to determine functions with a signed return type first
before corresponding variable assignments will be checked further.
* Would you like to collect function names for this purpose by a general analysis
  of more source files?
  (How do you think about to store them in a dedicated database?)

* Which couple of function calls will be interesting for you?

* Should the search approach take also recursively included files into account?

Regards,
Markus