C++ codegen regression: memset called on a result variable of importcpp type (v2)

[philip-wernersbach]

Version 2 of #5140.

Consider the following:

{.emit:"""
#import <cassert>

class C {
  public:
    int d;

    C(): d(1) { }

    C& operator=(const C other) {
      assert(d == 1);

      d = other.d;
      return *this;
    }
};
""".}

type C* {.final, importc: "C".} = object

proc newC*(): C {.importcpp: "C".}

proc mkC*(): C =
    result = newC()

discard mkC()

The assertion fails because Nim generates a memset for mkC's result:

N_NIMCALL(C, mkc_x4uLyT9aRomf9cN9bUnV4BPJg)(void) {
	C result0;
	nimfr("mkC", "test.nim")
	memset((void*)(&result0), 0, sizeof(result0));
	nimln(24, "test.nim");
	result0 = C();
	popFrame();
	return result0;
}

[Araq]

But you need to use importcpp to import the type and then the problem disappears.

[philip-wernersbach]

I see, can't believe I missed this. Thanks!