_vorbis_block_alloc assumes _ogg_malloc aligns to at least WORD_ALIGN

To guarantee WORD_ALIGN alignment, you need to align the pointer after 
calling _ogg_malloc(), or _ogg_realloc().

If you are doing cache tuning, you might want to push WORD_ALIGN fairly 
high, like 16 or 32 depending on the cache architecture.

possible patch:
*** block.c     2002/03/29 07:34:09     1.64
--- block.c     2002/04/12 11:02:00
***************
*** 115,120 ****
--- 115,122 ----
      /* highly conservative */
      vb->localalloc=bytes;
      vb->localstore=_ogg_malloc(vb->localalloc);
+     vb->localstore=(void*)(((long)((char*)vb->localstore+
+                          (WORD_ALIGN-1))) & ~(WORD_ALIGN-1));
      vb->localtop=0;
    }
    {
***************
*** 137,143 ****
    }
    /* consolidate storage */
    if(vb->totaluse){
!     vb->localstore=_ogg_realloc(vb->localstore,vb->totaluse+vb->
localalloc);
      vb->localalloc+=vb->totaluse;
      vb->totaluse=0;
    }
--- 139,148 ----
    }
    /* consolidate storage */
    if(vb->totaluse){
!     long tot=(vb->totaluse+vb->localalloc+(WORD_ALIGN-1)) & 
~(WORD_ALIGN-1);
!     vb->localstore=_ogg_realloc(vb->localstore,tot);
!     vb->localstore=(void*)(((long)((char*)vb->localstore+
!                          (WORD_ALIGN-1))) & ~(WORD_ALIGN-1));
      vb->localalloc+=vb->totaluse;
      vb->totaluse=0;
    }


It may be better to define a macro that does the alignment.