Move the Lisp_Fwd.bufoffset field back to the union

* src/lisp.h (struct Lisp_Fwd): With the predicate enum, we can now pack
the offset and the predicate into a one-word struct.
(XBUFFER_OFFSET): Use the new field name.
* src/buffer.c (DEFVAR_PER_BUFFER): Create the one-word struct.
* src/data.c (store_symval_forwarding): Use the new field name.

1 files changed, 9 insertions, 6 deletions

diff --git a/src/buffer.c b/src/buffer.c
index afc2f0f4d89..b1a835b7ac5 100644
--- a/src/buffer.c
+++ b/src/buffer.c
@@ -4980,14 +4980,17 @@ init_buffer (void)
    that nil is allowed too).  DOC is a dummy where you write the doc
    string as a comment.  */
 
-#define DEFVAR_PER_BUFFER(lname, vname, predicate, doc)         \
+#define DEFVAR_PER_BUFFER(lname, vname, predicate_, doc)        \
   do {                                                          \
-    static const struct Lisp_Fwd bo_fwd                         \
-        = { .type = Lisp_Fwd_Buffer_Obj,                        \
-            .bufoffset = offsetof (struct buffer, vname##_),    \
-            .u.bufpredicate = FWDPRED_##predicate };            \
+    static const struct Lisp_Fwd bo_fwd = {                     \
+      .type = Lisp_Fwd_Buffer_Obj,                              \
+      .u.buf = {                                                \
+        .offset = offsetof (struct buffer, vname##_),           \
+        .predicate = FWDPRED_##predicate_                       \
+      }                                                         \
+    };                                                          \
     static_assert (offsetof (struct buffer, vname##_)           \
-                   < (1 << 8 * sizeof bo_fwd.bufoffset));       \
+                   < (1 << 8 * sizeof bo_fwd.u.buf.offset));    \
     defvar_per_buffer (&bo_fwd, lname);                         \
   } while (0)