Implement posix_memalign for glibc.

malloc/malloc.c

@@ -4746,6 +4746,29 @@ free_atfork(mem, caller) Void_t* mem; const Void_t *caller;
 
 
 #ifdef _LIBC
+/* We need a wrapper function for one of the additions of POSIX.  */
+int
+__posix_memalign (void **memptr, size_t alignment, size_t size)
+{
+  void *mem;
+
+  /* Test whether the SIZE argument is valid.  It must be a power of
+     two multiple of sizeof (void *).  */
+  if (size % sizeof (void *) != 0 || (size & (size - 1)) != 0)
+    return EINVAL;
+
+  mem = __libc_memalign (alignment, size);
+
+  if (mem != NULL)
+    {
+      *memptr = mem;
+      return 0;
+    }
+
+  return ENOMEM;
+}
+weak_alias (__posix_memalign, posix_memalign)
+
 weak_alias (__libc_calloc, __calloc) weak_alias (__libc_calloc, calloc)
 weak_alias (__libc_free, __cfree) weak_alias (__libc_free, cfree)
 weak_alias (__libc_free, __free) weak_alias (__libc_free, free)