unix/coveragecpp: Verify struct-initializing macros' C++-compatibility.

Add code using all relevant macros to make sure they initialize
structs correctly.

Signed-off-by: stijn <[email protected]>

Author: stinos

ports/unix/coveragecpp.cpp

@@ -17,10 +17,61 @@ extern "C" {
 #include <py/runtime.h>
 }
 
+// Invoke all (except one, see below) public API macros which initialize structs to make sure
+// they are C++-compatible, meaning they explicitly initialize all struct members.
+mp_obj_t f0();
+MP_DEFINE_CONST_FUN_OBJ_0(f0_obj, f0);
+mp_obj_t f1(mp_obj_t);
+MP_DEFINE_CONST_FUN_OBJ_1(f1_obj, f1);
+mp_obj_t f2(mp_obj_t, mp_obj_t);
+MP_DEFINE_CONST_FUN_OBJ_2(f2_obj, f2);
+mp_obj_t f3(mp_obj_t, mp_obj_t, mp_obj_t);
+MP_DEFINE_CONST_FUN_OBJ_3(f3_obj, f3);
+mp_obj_t fvar(size_t, const mp_obj_t *);
+MP_DEFINE_CONST_FUN_OBJ_VAR(fvar_obj, 1, fvar);
+mp_obj_t fvarbetween(size_t, const mp_obj_t *);
+MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(fvarbetween_obj, 1, 2, fvarbetween);
+mp_obj_t fkw(size_t, const mp_obj_t *, mp_map_t *);
+MP_DEFINE_CONST_FUN_OBJ_KW(fkw_obj, 1, fkw);
+
+static const mp_rom_map_elem_t table[] = {
+    { MP_ROM_QSTR(MP_QSTR_f0), MP_ROM_PTR(&f0_obj) },
+};
+MP_DEFINE_CONST_MAP(map, table);
+MP_DEFINE_CONST_DICT(dict, table);
+
+static const qstr attrtuple_fields[] = {
+    MP_QSTR_f0,
+};
+MP_DEFINE_ATTRTUPLE(attrtuple, attrtuple_fields, 1, MP_ROM_PTR(&f0_obj));
+
+void nlr_cb(void *);
+void nlr_cb(void *){
+}
+
+// The MP_DEFINE_CONST_OBJ_TYPE macro is not C++-compatible because each of the
+// MP_DEFINE_CONST_OBJ_TYPE_NARGS_X macros only initializes some of _mp_obj_type_t's
+// .slot_index_xxx members but that cannot be fixed to be done in a deterministic way.
+
+
 #if defined(MICROPY_UNIX_COVERAGE)
 
 // Just to test building of C++ code.
 static mp_obj_t extra_cpp_coverage_impl() {
+    MP_DEFINE_NLR_JUMP_CALLBACK_FUNCTION_1(ctx, nlr_cb, (void *) nlr_cb);
+
+    // To avoid 'error: unused variable [-Werror,-Wunused-const-variable]'.
+    (void) ctx;
+    (void) f0_obj;
+    (void) f1_obj;
+    (void) f2_obj;
+    (void) f3_obj;
+    (void) fvar_obj;
+    (void) fvarbetween_obj;
+    (void) fkw_obj;
+    (void) map;
+    (void) dict;
+    (void) attrtuple;
     return mp_const_none;
 }