diff git a/malloc/obstack.h b/malloc/obstack.h
index 4b01cdfe4d..1cf18e5464 100644
 a/malloc/obstack.h
+++ b/malloc/obstack.h
@@ 116,22 +116,9 @@
# define PTR_INT_TYPE ptrdiff_t
#endif
/* If B is the base of an object addressed by P, return the result of
 aligning P to the next multiple of A + 1. B and P must be of type
 char *. A + 1 must be a power of 2. */

#define __BPTR_ALIGN(B, P, A) ((B) + (((P)  (B) + (A)) & ~(A)))

/* Similar to _BPTR_ALIGN (B, P, A), except optimize the common case
 where pointers can be converted to integers, aligned as integers,
 and converted back again. If PTR_INT_TYPE is narrower than a
 pointer (e.g., the AS/400), play it safe and compute the alignment
 relative to B. Otherwise, use the faster strategy of computing the
 alignment relative to 0. */

#define __PTR_ALIGN(B, P, A) \
 __BPTR_ALIGN (sizeof (PTR_INT_TYPE) < sizeof (void *) ? (B) : (char *) 0, \
 P, A)
+/* Align P to the next multiple of A + 1, where A + 1 is a power of 2,
+ A fits into unsigned long and P has type char *. */
+#define __PTR_ALIGN(B, P, A) ((P) + ((unsigned long)(P) & (A)))
#include