explaination of trampoline

[Paolo Bonzini]

> The c code for which i'm observing the effect is as follows.
> 
> int foo(int (*f)()){
>        (*f)();
> }
> main(){
>        int g(){printf("hello");}
>        foo(g);
> }

This one does not need a trampoline, because there would not be any 
difference if int g() was not a nested function -- g() has no static 
chain argument.  Try this one instead:

int foo(int (*f)()){
        (*f)();
}
main(int argc, char **argv){
        int g(){printf("hello, argc=%d\n", argc);}
        foo(g);
}

You will see trampolines in all their beauty.

Paolo