diff --git a/src/ChangeLog b/src/ChangeLog
index c8657265dab..3f66710b2bb 100644
--- a/src/ChangeLog
+++ b/src/ChangeLog
@@ -1,5 +1,8 @@
 2010-06-03  Glenn Morris  <rgm@gnu.org>
 
+	* m/hp800.h (alloca) [__NetBSD__ && __GNUC__]: No need to define it,
+	now that AH_BOTTOM does it.
+
 	* m/hp800.h (HAVE_ALLOCA):
 	* m/ibms390x.h (HAVE_ALLOCA): Do not define, no longer needed.
 
diff --git a/src/m/hp800.h b/src/m/hp800.h
index fe44fd3da8d..3889a1a3e60 100644
--- a/src/m/hp800.h
+++ b/src/m/hp800.h
@@ -29,12 +29,5 @@ along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.  */
    This flag only matters if you use USE_LISP_UNION_TYPE.  */
 #define EXPLICIT_SIGN_EXTEND
 
-/* Systems with GCC don't need to lose. */
-#ifdef __NetBSD__
-# ifdef __GNUC__
-#  define alloca __builtin_alloca
-# endif /* __GNUC__ */
-#endif /* __NetBSD__ */
-
 /* arch-tag: 809436e6-1645-4b92-b40d-2de5d6e7227c
    (do not change this comment) */