diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index 06f63422d2f..00fa8bbb9c3 100644
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,5 +1,7 @@
 2005-10-28  Mark Kettenis  <kettenis@gnu.org>
 
+	* ppc-tdep.h (PPC_INSN_SIZE): Define.
+
 	* inf-ttrace.c (inf_ttrace_mourn_inferior): Remove redundant cast.
 	(inf_ttrace_kill): Renamed from inf_ttrace_kill_inferior.
 	(inf_ttrace_target): Resort assignments.
diff --git a/gdb/ppc-tdep.h b/gdb/ppc-tdep.h
index 5037c11788a..9abbf5c37b6 100644
--- a/gdb/ppc-tdep.h
+++ b/gdb/ppc-tdep.h
@@ -1,7 +1,7 @@
 /* Target-dependent code for GDB, the GNU debugger.
 
-   Copyright 2000, 2001, 2002, 2003, 2004 Free Software Foundation,
-   Inc.
+   Copyright 2000, 2001, 2002, 2003, 2004, 2005
+   Free Software Foundation, Inc.
 
    This file is part of GDB.
 
@@ -381,4 +381,7 @@ enum
     ppc_spr_pbu2      = 1023
   };
 
-#endif
+/* Instruction size.  */
+#define PPC_INSN_SIZE 4
+
+#endif /* ppc-tdep.h */