More C++ compilability work: mrb_obj_alloc void* conversions

One of the biggest set of changes needed to make C++ compile, is that you
can't autoconvert "void*" to a different pointer type without a cast (you
can of course, convert pointers *to* "void*"!)

For the first part, convert the users of "mrb_obj_alloc".  Since it has
to return something, make it RBasic* (that's what mrb_obj_alloc() is
operating on anyway).  This way, even in C you'll get a warning if you
don't cast it.

For places where there are a lot of similar calls to mrb_obj_alloc(),
this can be easily hidden through a macro.  I did this in string.c:
    #define mrb_obj_alloc_string(mrb) ((struct RString *) mrb_obj_alloc((mrb), MRB_TT_STRING, (mrb)->string_class))

I also updated the mrb_object() macro to also return a RBasic* -- my
previous commit changed that from "void*" -> "RObject*", but I figure
it should be consistent with mrb_obj_alloc()

1 files changed, 2 insertions, 2 deletions

diff --git a/src/hash.c b/src/hash.c
index 45219cb40..3674a30c8 100644
--- a/src/hash.c
+++ b/src/hash.c
@@ -100,7 +100,7 @@ mrb_hash_new_capa(mrb_state *mrb, size_t capa)
 {
   struct RHash *h;
 
-  h = mrb_obj_alloc(mrb, MRB_TT_HASH, mrb->hash_class);
+  h = (struct RHash *) mrb_obj_alloc(mrb, MRB_TT_HASH, mrb->hash_class);
   h->ht = kh_init(ht, mrb);
   kh_resize(ht, h->ht, capa);
   h->iv = 0;
@@ -197,7 +197,7 @@ mrb_hash_dup(mrb_state *mrb, mrb_value hash)
   khash_t(ht) *h, *ret_h;
   khiter_t k, ret_k;
 
-  ret = mrb_obj_alloc(mrb, MRB_TT_HASH, mrb->hash_class);
+  ret = (struct RHash *) mrb_obj_alloc(mrb, MRB_TT_HASH, mrb->hash_class);
   ret->ht = kh_init(ht, mrb);
 
   if (!RHASH_EMPTY_P(hash)) {