Error on passing nested structure by value

[Wuerfel21]

typedef	struct {
    int x,y;
} Point;
typedef	struct {
    Point ul,lr;
} Rect;

void foo(Rect r) {
    
}

void main() {
    Rect r = {{1,2},{3,4}};
    foo(r);
}

begets
structpass.c:14: error: Internal error, couldn't find object variable with offset 4

[Wuerfel21]

Ok, it seems that struct-by-value passing is ultra cursed and doesn't work at all with members that aren't long sized: 8/16 bit compiles junk code, 64 bit runs into the same error as nested structs...

[totalspectrum]

Yes, the struct passing code is totally bogus :(. Probably we should just bail and always pass structures by copy+reference instead of by value, except for the few structures that can fit this pattern. The existing code probably works OK for bytecode, but that's because everything goes on the stack instead of into registers.

[Wuerfel21]

As of 2941442 it at least doesn't seem to explode, but instead we get MY FAVORITE: Compiler-generated heap allocation. It doesn't even free it afterwards, how rude.
This really ought to be changed to an alloca-type thing.