X-Git-Url: https://git.distorted.org.uk/~mdw/sod/blobdiff_plain/6bc944c3cebb89056d9ed0b53eff6260909291a9..ed00691544c3b6d4ad15b1c7ef975964ea72b0b6:/lib/sod.h

diff --git a/lib/sod.h b/lib/sod.h
index cb6b046..efac06b 100644
--- a/lib/sod.h
+++ b/lib/sod.h
@@ -53,7 +53,7 @@ struct sod_vtable {
  * these.
  */
 struct sod_instance {
-  struct sod_vtable *_vt;		/* Pointer to (chain's) vtable */
+  const struct sod_vtable *_vt;		/* Pointer to (chain's) vtable */
 };
 
 /* Information about a particular chain of superclasses.  In each class,
@@ -76,14 +76,15 @@ struct sod_chain {
  * Arguments:	@chead@ = nickname of target chain's head
  *		@obj@ = pointer to an instance chain
  *
- * Returns:	Pointer to target chain, as a @char *@.
+ * Returns:	Pointer to target chain, as a @void *@.
  *
  * Use:		Utility for implementing cross-chain upcasts.  It's probably
  *		not that clever to use this macro directly; it's used to make
  *		the automatically-generated upcast macros more palatable.
  */
 
-#define SOD_XCHAIN(chead, obj) ((char *)(obj) + (obj)->_vt->_off_##chead)
+#define SOD_XCHAIN(chead, obj)						\
+  ((void *)((char *)(obj) + (obj)->_vt->_off_##chead))
 
 /* --- @SOD_OFFSETDIFF@ --- *
  *
@@ -124,7 +125,7 @@ struct sod_chain {
   ((struct cls##__ilayout *)						\
    ((char *)(obj) - offsetof(struct cls##__ilayout, chead)))
 
-/* --- @SOD__CAR@ --- *
+/* --- @SOD_CAR@ --- *
  *
  * Arguments:	@...@ = a nonempty list of arguments
  *
@@ -132,7 +133,7 @@ struct sod_chain {
  */
 
 #if __STDC_VERSION__ >= 199901
-#  define SOD__CAR(...) SOD__CARx(__VA_LIST__, _)
+#  define SOD_CAR(...) SOD__CARx(__VA_LIST__, _)
 #  define SOD__CARx(a, ...) a
 #endif