cppmintf: implements multiple intefaces in c++

_demo/cppmintf/foo/bar/bar.cpp

@@ -0,0 +1,17 @@
+#include <stdio.h>
+#define interface struct
+
+interface ICalc {
+	virtual double calc(double v) = 0;
+};
+
+interface IVal {
+	virtual int val() = 0;
+};
+
+class Callback : public ICalc, public IVal {
+};
+
+extern "C" void f(Callback* cb) {
+	printf("val: %d\ncalc(2): %lf\n", cb->val(), cb->calc(2));
+}

_demo/cppmintf/foo/foo.go

@@ -0,0 +1,42 @@
+package foo
+
+import (
+	"unsafe"
+)
+
+const (
+	LLGoFiles   = "bar/bar.cpp"
+	LLGoPackage = "link"
+)
+
+// -----------------------------------------------------------------------------
+
+type ICalc struct {
+	Vptr *ICalcVtbl
+}
+
+type ICalcVtbl struct {
+	Calc unsafe.Pointer
+}
+
+// -----------------------------------------------------------------------------
+
+type IVal struct {
+	Vptr *IValVtbl
+}
+
+type IValVtbl struct {
+	Val unsafe.Pointer
+}
+
+// -----------------------------------------------------------------------------
+
+type Callback struct {
+	ICalc
+	IVal
+}
+
+//go:linkname F C.f
+func F(cb *Callback)
+
+// -----------------------------------------------------------------------------