diff --git a/sys/src/cmd/audio/libvorbis/mdct.c b/sys/src/cmd/audio/libvorbis/mdct.c
index 1f0ee3c53..d6db82227 100644
--- a/sys/src/cmd/audio/libvorbis/mdct.c
+++ b/sys/src/cmd/audio/libvorbis/mdct.c
@@ -495,7 +495,8 @@ void mdct_forward(mdct_lookup *init, DATA_TYPE *in, DATA_TYPE *out){
   int n2=n>>1;
   int n4=n>>2;
   int n8=n>>3;
-  DATA_TYPE *w=malloc(n*sizeof(*w)); /* forward needs working space */
+  DATA_TYPE *wbuf=malloc(n*sizeof(DATA_TYPE)); /* forward needs working space */
+  DATA_TYPE *w=wbuf;
   DATA_TYPE *w2=w+n2;
 
   /* rotate */
@@ -560,5 +561,5 @@ void mdct_forward(mdct_lookup *init, DATA_TYPE *in, DATA_TYPE *out){
     w+=2;
     T+=2;
   }
-  free(w);
+  free(wbuf);
 }