-# if !defined SYSTEM_MALLOC && !defined DOUG_LEA_MALLOC && !defined HYBRID_MALLOC
-# define USE_ALIGNED_ALLOC 1
-# ifndef HAVE_ALIGNED_ALLOC
-/* Defined in gmalloc.c. */
-void *aligned_alloc (size_t, size_t);
-# endif
-# elif defined HYBRID_MALLOC
-# if defined HAVE_ALIGNED_ALLOC || defined HAVE_POSIX_MEMALIGN
-# define USE_ALIGNED_ALLOC 1
-# define aligned_alloc hybrid_aligned_alloc
-/* Defined in gmalloc.c. */
-void *aligned_alloc (size_t, size_t);
-# endif
-# elif defined HAVE_ALIGNED_ALLOC
+# if (defined HAVE_ALIGNED_ALLOC \
+ || (defined HYBRID_MALLOC \
+ ? defined HAVE_POSIX_MEMALIGN \
+ : !defined SYSTEM_MALLOC && !defined DOUG_LEA_MALLOC))