diff --git a/src/alloc.c b/src/alloc.c
index 90c743a5d38..1be5e2b8f1d 100644
--- a/src/alloc.c
+++ b/src/alloc.c
@@ -4488,7 +4488,11 @@ mark_stack ()
      needed on ia64 too.  See mach_dep.c, where it also says inline
      assembler doesn't work with relevant proprietary compilers.  */
 #ifdef __sparc__
+#ifdef __sparc64__
+  asm ("flushw");
+#else
   asm ("ta 3");
+#endif
 #endif
 
   /* Save registers that we need to see on the stack.  We need to see