diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index b0e6c3052b55..9efdd328535f 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -47,6 +47,10 @@
 	PR target/47129
 	* config/ia64/ia64.c: Include "dwarf2out.h" .
 
+	PR target/47063
+	* config/alpha/vms.h (MALLOC_ALIGNMENT): Don't undef / define.
+	(MALLOC_ABI_ALIGNMENT): Undef / define.
+
 2010-12-29  Jakub Jelinek  <jakub@redhat.com>
 
 	PR tree-optimization/47074
diff --git a/gcc/config/alpha/vms.h b/gcc/config/alpha/vms.h
index 9985b67728ed..fab0f2577621 100644
--- a/gcc/config/alpha/vms.h
+++ b/gcc/config/alpha/vms.h
@@ -72,8 +72,8 @@ along with GCC; see the file COPYING3.  If not see
 #define MAX_OFILE_ALIGNMENT 524288  /* 8 x 2^16 by DEC Ada Test CD40VRA */
 
 /* The maximum alignment 'malloc' honors.  */
-#undef  MALLOC_ALIGNMENT
-#define MALLOC_ALIGNMENT ((TARGET_MALLOC64 ? 16 : 8) * BITS_PER_UNIT)
+#undef  MALLOC_ABI_ALIGNMENT
+#define MALLOC_ABI_ALIGNMENT ((TARGET_MALLOC64 ? 16 : 8) * BITS_PER_UNIT)
 
 #undef FIXED_REGISTERS
 #define FIXED_REGISTERS  \