diff --git a/thunk.h b/thunk.h
index 5be8f91..c295766 100644
--- a/thunk.h
+++ b/thunk.h
@@ -113,7 +113,7 @@
       defined(HOST_PARISC) || defined(HOST_SPARC64)
             return 4;
 #elif defined(HOST_PPC)
-            return HOST_LONG_SIZE;
+            return TARGET_ABI_BITS / 8;
 #else
             return 2;
 #endif