// foo.c

typedef struct {
	unsigned bar;
	unsigned baz;
} Foo;

Foo setFoo(unsigned a, unsigned b) {
	Foo foo;
	foo.bar = a;
	foo.baz = b;
}

void setFooByPointer(unsigned a, unsigned b, Foo *pFoo) {
	pFoo->bar = a;
	pFoo->baz = b;
}

// strukt.d

import std.stdio;

struct Foo {
	uint bar;
	uint baz;
}

extern (C) Foo setFoo(uint a, uint b);
extern (C) void setFooByPointer(uint a, uint b, Foo* pFoo);

void main() {
	Foo foo;
	setFooByPointer(31337, 42, &foo);
	writeln(foo);
	foo = setFoo(31337, 42);
	writeln(foo);
}

// build

$ dmd -c strukt.d -ofstrukt.o
$ gcc -c foo.c -o foo.o
$ dmd foo.o strukt.o -ofstrukt

// run

$ ./strukt 
Foo(31337, 42)
Foo(42, 0)

// expected:
Foo(31337, 42)
Foo(31337, 42)