[cocci] Returning statically allocated nested structs

[Peter Senna Tschudin <peter.senna@gmail.com>]

Dear list,

I am trying to come up with a semantic patch to detect uses of nested
structs, more specifically:
 - the nested struct is statically allocated
 - the statically allocated nested struct is returned by a function.

Here is an example:

struct inner {

    /* some inner struct stuff*/

} inner;

struct outer  {

    /* some outer struct stuff*/

    struct inner i; // The kind of nesting I care about
    struct inner is[SOME_MAGIC_NUMBER]; // The kind of nesting I care about too

    struct inner *ip; // Nah, this is boring. I don't care about boring
} outer;

void sillyfu() {
    struct outer ou = { }; // initialization does not matter.
    struct outer *oup = NULL; // Nah, this is boring. I don't care about boring

    /* some serious silly stuff */

    return ou;
}

I remember that there are some details for detecting structs
effectively, and as I am investigating a code base with over 1.2M
lines of code, I would like to ask for pointers of where to start.

Thank you!

Peter

-- 
                         Peter